JBR 2010-4 by office

WETTEREN 1

P 702083

Volume 93 Page 171-234 July-August

Bimonthly

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2010

DIAGNOSTIC AND INTERVENTIONAL IMAGING, RELATED IMAGING SCIENCES, AND CONTINUING EDUCATION

ORGANE DE LA SOCIETE ROYALE BELGE DE RADIOLOGIE (SRBR) ORGAAN VAN DE KONINKLIJKE BELGISCHE VERENIGING VOOR RADIOLOGIE (KBVR)

JBR-BTR ♦ 93/4 ♦ 2010 Journal Belge de ♦ Belgisch Tijdschrift voor ♦ RADIOLOGIE

Founded in 1907 A bimonthly journal devoted to diagnostic and interventional imaging, related imaging sciences, and continuing education Contents Contribution of US and CT for diagnosis of intraperitoneal focal fat infarction (IFFI) : a pictorial review. B. Coulier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . An unusual cause of pelvic hemorrhage: multidetector CT diagnosis of inferior mesenteric vein injury. D. Karaosmanoglu, M. Boge, E. Akpinar, M. Karcaaltincaba . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Post-traumatic hepatic arterial pseudoaneurysm and arterioportal shunt. J. Maes, O. d’Archambeau, A. Snoeckx, B. Op de Beeck, M. Voormolen, P.M. Parizel . . . . . . . . . . . . . . . . . . . . . . . . Leiomyomatosis peritonealis disseminate in a 50-year-old woman: imaging findings. A. Talebian Yazdi, K. De Smet, B. Ilsen, F. Vandenbroucke, J. de Mey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Intracranial germ cell tumor. J. Kreutz, L. Rausin, E. Weerts, M. Tebache, J. Born, C. Hoyoux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Spontaneous cholecystocutaneous abscess. W.J. Metsemakers, I. Quanten, F. Vanhoenacker, T. Spiessens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Small bowel obstruction due to an internal herniation through a defect of the broad ligament. P. Mailleux, A. Ramboux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Acetabular osteoid osteoma treated by percutaneous radiofrequency ablation: delayed articular cartilage damage. P.P. Bosschaert, F.C. Deprez . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pigmented villonodular synovitis of the midfoot. P. Sierens, M. Shahabpour, V. Gombault, F. Machiels, M. Kichouh, M. De Maeseneer . . . . . . . . . . . . . . . . . . . . . . .

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SPECIAL ARTICLE X-ray control of borders and of internal security. H. Vogel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210

REVIEW ARTICLE Vascular liver anatomy and main variants: what the radiologist must know. M. Seco, P. Donato, J. Costa, A. Bernades, F. Caseiro-Alves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215 Detachable coils for embolotherapy of high flow pulmonary arteriovenous malformation. M. Laureys, A. Nazeri, P. Mendes da Costa, L. Divano . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224

IMAGES IN CLINICAL RADIOLOGY CT imaging of ascaris lumbricoides. F.C. Deprez, C. Pauls, T. Puttemans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . An uncommon cause of asymptomatic crazy paving pattern. C. Schoofs, L. Bladt, W. De Wever . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mycotic aneurysm of the superior mesenteric artery. W. Siemons, S. Heye . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bitalamic acute stroke: artery of Percheron. F.C. Deprez, P. Bosschaert, X. Leysen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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LETTER TO THE EDITOR Two cases of fistulating gallbladder disease. N. Campbell, J. Feeney . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 Forthcoming courses and meetings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Classified services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188, 192, Instructions to Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Subscribers information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Advertising index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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The terms used for indexation of subjects were developed by the Radiological Society of North America (RSNA) over a period of years. Their use here is by permission of the RSNA. The terms may not be used in any other index, print or electronic, except by specific permission of RSNA. ◆◆ Indexed in Index Medicus and in Zentralblatt Radiologie. Evaluated for Medline User, EMBASE and CANCERNET. Abstracted in Excerpta Medica Journals. ◆

JBR–BTR, 2010, 93: 171-184.

CONTRIBUTION OF US AND CT FOR DIAGNOSIS OF INTRAPERITONEAL FOCAL FAT INFARCTION (IFFI): A PICTORIAL REVIEW B. Coulier1 The term IFFI – for Intraperitoneal Focal Fat Infarction – includes various acute abdominal clinical conditions in which focal fatty tissue necrosis represents the common pathologic denominator. Only differing by their various anatomical locations and dimensions, all cases nevertheless present rather similar clinical signs, aetiology, radiological features and prognosis. In clinical practise, most cases of IFFI concern torsion and/or infarction of the greater omentum or epiploic appendages. Rarer types of torsion and/or infarction of lipomatous appendages of the hepatic falciform ligament and of the lesser omentum have also been reported. Cases are finally described in the paediatric population. US and merely CT have been shown having a high sensitivity and specificity for the diagnosis of IFFI and in most cases the clinical evolution is spontaneously favourable. For these two reasons, the option of conservative treatment after specific imaging diagnosis now represents the other common denominator of IFFI. Such a safe and unambiguous imaging diagnosis of IFFI represents thus an important challenge for each abdominal radiologist with the intention of persuading the referent clinician to avoid unnecessary surgery for their patients. The aim of this pictorial review is to extensively explore not only the classical imaging findings of various types of IFFI but also to review the normal US and MDCT anatomy of the fatty abdominal structures being usually implicated in IFFI. More rare or atypical presentations are also illustrated as well as subacute findings and sequels. All reported patients were collected in our department during a 7-year-period and most were successfully treated conservatively. Key-words: Abdomen, acute conditions – Abdomen, CT – Abdomen, US.

The term IFFI – for Intraperitoneal Focal Fat Infarction – was introduced by van Breda Vriesmann in 1999 (1) to gather and qualify various acute abdominal clinical conditions having focal fatty tissue necrosis as common denominator, presenting rather similar clinical signs, aetiology, radiological features, prognosis and treatment and finally only differing in their anatomical location and dimensions. First considered as being rare, IFFI has received much attention during the last two decades. The mean reason are the continuous development of CT and US technology and their exponentially use as first line imaging modalities to explore patients presenting with acute abdominal conditions. It is now suggested that their true frequency is much higher than previously considered and numerous case reports, small series and pictorial reviews have been published on this subject. Because the disease has been shown to have a spontaneously favourable evolution in most cases the option of successful conservative treatment has now become the other common denominator of IFFI.

A safe and unambiguous imaging diagnosis of IFFI thus currently represents a challenge for any abdominal radiologist in order to avoid unnecessary surgery. In this large pictorial review we first revisit the normal US and CT anatomy of the fatty abdominal structures being usually implicated in IFFI. The classical but also nontypical imaging findings of IFFI are then extensively re-explored. Finally more rare or nontypical presentations are also illustrated as well as subacute findings and sequels. All reported cases were collected in our department over a 7-yearperiod. The great majority of patients were imaged with MDCT and most patients were successfully treated conservatively. Discussion Epiploic appendages Epiploic appendages (EA) correspond to peritoneum covered fatty fingerlike structures about 2 to 5 cm long and 1-2 cm thick (1-5). They are about 50-100 in number, arise from the serosal surface of the colon, con-

From: 1. Department of Diagnostic Radiology, Clinique St Luc, Bouge, Belgium. Address for correspondence: Dr B. Coulier, M.D., Department of Diagnostic Radiology, Clinique St Luc, Rue St Luc 8, B-5004 Bouge, Belgium. E-mail: bcoulier@skynet.be

tain adipose tissue and vessels and are distributed in two parallel rows along the taenia libera and the taenia omentalis, from the cecum to the rectosigmoid junction (Fig. 1, 2). The largest are found along the descending and sigmoid colon. Those developed along the transverse colon are smaller. It is worthwhile to note that the transverse colon usually harbours only a single row of EA along its teania libera because de greater omentum attaches along the teania omentalis (Fig. 3). Nevertheless isolated EA may occasionally occur at this last site as well as over the vermiform appendix or over a small bowel loop. Their somewhat precarious terminal blood supply – one or two small colonic end-arteries and a small draining vein –, their pediculated nature and thus their great mobility are factors increasing their susceptibility for torsion and/or infarction. The precise function of EA is not yet known but they can provide some defence against local inflammation similar to the protective properties of the greater omentum. They also represent a site for fat storage (4). Under normal circumstances, the EA are not visible during ultrasound studies or abdominal CT unless they are surrounded by a sufficient amount of ascitic fluid (Fig. 1), free peritoneal gas or intermingled with

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Fig. 1. — Epiploic appendages are commonly visible in patients presenting with massive ascitis. US appearance (A, B) of rows of normal epiploic appendages (white arrow) floating in ascitis in the left iliac fossa in a cirrhotic patient. Similar images (C, D) obtained during abdominal MDCT. Anatomic relation (E, F) between the appendages and the axis of the colon: two parallel rows of appendages, also well demonstrated on the coronal oblique MPR view (C) are running along the colon inserting near the anti mesenteric taenia (taenia libera –black arrow– and teania omentalis –white arrow–). They are vascularised by secondary terminal branches of the vasa recta longa of the colon (black arrowheads).

peritoneal inflammatory processes and/or when their covering peritoneal sheet is inflamed (4) (Fig. 2). Acute epiploic appendagitis (AEA) is an uncommon cause of abdominal pain that has only recently been recognized and whose diagnosis primarily relies on cross sectional imaging

– most often CT or US – (3). It is attributable either to torsion or to spontaneous venous thrombosis of an EA. The blood supply is cut off to the fat cells that compose the bulk of the EA, with resultant ischemia and possibly infarction. The necrosis can sometimes be haemorrhagic (Fig. 5).

Primary AEA present as an acute clinical condition which can mimic diverticulitis, appendicitis or other more serious causes of acute abdominal pain (5). The sigmoid colon and the caecum are the predominant physiological sites of occurrence but all parts of the colon may be affected. AEA can occur at any age and men are slightly more affected than women (7:3 ratio) (1, 5). On clinical examination patients describe a localised, strong, non migratory, sharp pain which usually started after a specific physical movement of their body like postprandial exercise (1, 5, 6). Abdominal local tenderness is present in all patients. There is a lack of fever, vomiting or other complaints. Leucocytosis in found in only about 20% of cases. Clinically it is most often mistaken for acute diverticulitis. Approximately 7,1% of patients investigated to exclude sigmoid diverticulitis have imaging findings of primary AEA (7). When it involves the caecum, it may be mistaken clinically for acute appendicitis. In most cases primary AEA has virtually pathognomonic CT findings (Fig. 4, 5, 6), appearing as a pericolonic, generally oval-shaped lesion with fat attenuation – but with higher attenuation (mean,-60HU) than uninvolved fat (mean,120HU) –, thickened visceral peritoneal lining, and periappendageal fat stranding (8, 9). Additional CT findings may include a longitudinal linear area or a central high-attenuating dot or focus and, as well as mass effect, focal wall thickening of the adjacent colon, or both. The high density central dot or focus - found in about 54% of cases - is believed to represent a thrombosed vessel within the inflamed appendix (3). Follow-up imaging of epiploic appendagitis are not systematically performed because of the benign nature of the lesion and the generally spontaneously healing. Nevertheless it is important to be aware of the evolutionary follow-up CT findings of acute epiploic appendagitis because these findings may persist for several months after disappearance of the clinical symptoms (3) (Fig. 7). With time the AEA decreases in size, usually to a small lesion with fat attenuation – that may become more similar to that of uninvolved mesenteric fat - but sometimes to a nugget with soft tissue attenuation that reflects scar issue deposition (3, 9). It also change in shape and contour usually from a

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Fig. 2. — Normal epiploic appendages also appear clearly when inflammatory processes occur around them and/or when their covering peritoneal sheet is inflamed. Transverse MPR view (A), sagittal oblique MPR view (B) (along the white line) and cross section view of the sigmoid colon (C) (along the black line ) show enhanced visualisation -due to peritoneal irritation- of the two parallel rows of epiploic appendages of the sigmoid colon (white arrows) in a patient presenting with colonic diverticulitis. The feeding vessels are well visible (black arrowhead). In another case or perforated diverticular sigmoiditis (D-F) the digitiform appendages (white arrows) are enhanced by the presence of fluid and irritation of the peritoneum. The vicinity between the appendages and the diverticula is also illustrated (white arrowheads). Free intraperitoneal gas due to perforation is retained between the appendages (black arrow).

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Fig. 3. — More deeply located rows of epiploic appendages are physiologically found along the internal side of the ascending colon and under the transverse colon. These may also be sponteanously seen in the presence of ascitis and/or peritoneal irritation. Transverse (A), sagittal (B) and coronal (C) MPR views in a patient presenting with massive hydro pneumoperitoneum. A continuous row of appendages (white arrowheads) are hanging along the taenia libera of the transverse colon (black arrow) and thus under the greater omentum (black star); white star = transverse mesocolon.

well-defined smooth oval shape to a structure with a shape that is irregular, oval or perfectly round. Classical fat stranding and/or adjacent bowel changes also improve around the healing appendagitis (3, 9). In the later course, the infarcted tissue can calcify, and a detachment of the epiploic appendage may be a source of “loose intraperitoneal bodies” or “peritoneal mice” incidentally found during laparoscopy or during radiologic evaluation (5) (Fig. 8). During ultrasound the lesion typically appears as an hyperechoic nodule of about 2 or 3 cm generally underneath the anterior abdominal wall at the site of maximum tenderness. The nodule is typically noncompressible and surrounded by a hypoechoic halo representing the inflamed peritoneum (1, 5, 9). Falciform ligament The falciform ligament (FL) is formed by two layers of peritoneum and contains a variable amount of extraperitoneal fat along with the remnants of the umbilical vein and

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Fig. 4. — A selection of very typical CT findings in different cases of acute epiploic appendagitis (AEA): sagittal (A) and axial (B) MPR views of an AEA of the anterior portion of the descending colon. Axial (c & d) views of another AEA of the left colon. In this patient (E, F) presenting with an acute abdominal pain related to a fresh AEA (white arrow) three older atrophic infarcted appendages (black arrows) are fortuitously demonstrated. In each case of AEA, the inflammatory necrotic lipomatous appendage measures 1,5 to 2 cm, contains dense structures probably corresponding to thrombosed vessels, appears circumscribed by a thickened inflammatory peritoneum and surrounded by a more subtle halo of inflammatory neighbouring fat tissue constituted by other EA or portions of the GO.

the ligamentum teres (10). Starting at the umbilicus in the midline, it passes to the right of the midline to connect the liver at the level of the accessory fissure. Fatty appendages are also commonly found on the FL during coelioscopy and are occasionally spontaneously visible during abdominal CT in patients presenting with ascitis or pneumoperitoneum (Fig. 9). Except the ligamentum teres, the FL complex usually remains undistinguishable from other peritoneal and properitoneal fatty structures (11). Surgical lesions implicating the FL are extremely uncommon and are represented by the rare internal hernia through the ligament, cystic lesions – primary congenital cysts or secondary infectious, neoplastic or

traumatic cysts – and rare extension of cholecystitis (11, 12). Lipomas of the FL are also rare described lesions (13). Torsion of the FL or of a lipomatous appendage of the FL is a very rare cause of acute abdominal pain and only five cases have been described as separate case reports (10, 14). The presentation is very similar to omental torsion with localized peritonism without fever or elevated white cell count and the differential diagnosis has to be made essentially with cholecystitis and perforated gastroduodenal ulcer. The US and CT appearances of a torsion of the free fatty end or of an appendage of the FL is very similar to that of AEA or omental torsion except the location. CT and particularly MPR is obvious for adequately

identifying the lesion as separate from the surrounding structures (10) and US may be useful to demonstrate the fact that the lesion doesn’t move with breathing, thereby proving its superficial extraperitoneal nature (14) (Fig. 9). All published cases have been operated but it should be suggested that a better knowledge and thus a better recognition of the entity could also avoid unnecessary surgery. Greater omentum Anatomically, the GO is a large free-hanging mesenteric tissue apron arising from the greater gastric curvature, crossing the transverse colon and descending in front of the viscera down to the symphysis (15, 16). After a distance

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Fig. 5. — A 45-year-old patient presented with deep pain in the right iliac fossa. US (A) demonstrated a 5 cm digitiform hypoechoic structure (white arrow) surrounded by inflammatory plastron and first evocating atypical paracecal necrotic appendicitis. Unenhanced abdominal MDCT with sagittal (B) and coronal (C) MPR confirmed the ultrasound data. The hypothesis of appendicitis was rejected because the structure failed to join the cecum. Laparoscopy revealed a necrotic and hemorrhagic appendage. The hemorrhagic necrosis explained the unusual imaging findings.

Fig. 6. — Atypical case of AEA of the right upper abdominal quadrant found in a 73-year old male (white arrows). On coronal MPR views (A, B) it is found hanging at the right angle of the colon (along the taenia libera). The thrombosed vascular pedicle is visible (black arrow); During ultrasound (C) with colour Doppler (D) the painful lesion is typically found nonvascular. It appears rather superficial, situated just under the abdominal wall because of the unusual prehepatic projection of the GO well identified through its vessels (black arrowheads on A). A spontaneous healing was obtained with conservative medical treatment.

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C Fig. 7. â&#x20AC;&#x201D; Subacute and chronic epiploic appendagitis (A-C) present as small lipomatous balls which are still attached to the colon (white arrowheads) or already free into the peritoneal cavity (black arrowheads). The diameter of the lesion is frankly inferior to the diameter encountered in the acute phase. The shape is more round and the neighbouring plastron has disappeared. Small foci of calcifications appear. On B the appendage has migrated into an inguinal hernia.

that usually ranges from 14 to 36 cm, it turns superiorly on itself to drape over the transverse colon and extend to the retroperitoneal pancreas (17). The descending and ascending portions usually fuse to form a four layer vascular fatty apron, with a space continuous with the lesser sac sometimes separating the two sets of layers (16, 17) (Fig. 10). The GO is composed of a trabecular connective tissue framework that carries arteries, veins, lymphatics and fat pads (15). The arterial supply of the GO is determined by the right and left gastroepiploic arteries receiving their blood supply from the celiac trunk, the left one by the lineal artery and the right, a stronger one, from the gastroduodenal artery which in turn carries blood from the superior mesenteric artery (15). Both gastroepiploic arteries pass tortuously along the greater gastric curvature and decrease in diameter by giving off gastric and epiploic branches at a right/left ratio of 3:1. About 5 to 13 epiploic arteries originate from the right gastroepiploic

artery. Only one main epiploic artery emerges from the left gastroepiploic artery. These arteries descend mostly at right angles to the greater curvature and bifurcate close to the omental margin, where they eventually anastomose through small branches with adjacent epiploic arteries. The venous drainage parallels the arteries and empties into the portal system. The identification of this rich vascular network and particularly that of the essentially vertical course of the epiploic vessels (particularly the veins which are generally twice as large as the arteries) constitutes the main landmark for current prompt identification of the GO during abdominal MDCT. These vessels may be clearly identified in 100% of patients (18) (Fig. 10). The GO represents the most superficial fatty intraperitoneal apron and thus its free edge can be easily identified during scrupulous up and down cine view analysis of the MDCT axial views just at the level where the fatty omental apron abruptly disappears allowing the

intestines to lie directly beneath the abdominal wall (18). Segmental omental infarction is a rare and uncommon acute disorder that simulates common surgical emergencies such as cholecystitis, appendicitis, or diverticulitis (16). Although omental infarctions have been reported in various portions of the GO most cases (90%) concern right-sided segmental infarction (19, 20). Left sided infarction is rare and only sporadically reported (21, 22). Due to the increasing use of US and CT and now MDCT evaluation in the setting of acute abdominal pain, infarction of the GO has gained much interest, especially because it may also be managed conservatively (1, 2, 19, 23). The exact etiology and pathogenesis of acute pathology is unknown (2, 16, 20). Some authors have suggested that congenitally anomalous fragile blood supply to the right lower portion of the greater omentum renders this region prone to infarction (24). Other authors suggest a different embryonic origin for the right side of the greater omentum with more fragile blood vessels which are more susceptible to elongation and secondary occlusions (25). Variations in blood supply to the right omental edge associated with obesity or trauma, overeating, hypercoagulability, coughing or a sudden change in position have also been suggested as predisposing factors. Other authors suggest venous engorgement after heavy meals or venous elongation produced by excessive weight of the greater omentum as a cause of infarction, since the higher prevalence of the syndrome in the obese population. Significant anatomic variations, some of which being related to sex, have recently been described during a 64-row MDCT study (18). These variations first concern the length, shape and the relative thickness of the GO. Among theses variations, the projection of a less or more important portion of the GO into the pre-hepatic sub-phrenic space appears to be an almost exclusive male feature (32% in males versus 2% in females) and in patients presenting with this feature the epiploic vessels appear somewhat crooked around the falciform ligament on 3D reformations (Fig. 11, 12). This anatomic variant may also explain the fact that omental infarction are first more common on the right but also more common in males (adult and children) than in

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Fig. 8. — Calcified and detached endstage epiploic appendages (white arrows) may be secondarily retained in numerous recesses of the peritoneal cavity such as folds of the diaphragm above the liver dome (A), external inguinal fossa (b) (US and MDCT), the Douglas pouch (C, D) or in the bottom of a large inguinal hernia containing a large portion of the GO (E) (black arrowhead).

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females with a sex ration varying between 2:1 to 4:1 (18). It is possible that during exertion with increase of abdominal pressure or after heavy meals (predisposing situations that have been proposed in the pathogenesis of omental infarction) this vascular crooking increases leading to infarction or torsion. Is this subphrenic projection of the GO a permanent feature or only a transient phenomenon that disappear in upright position is a question that cannot be answered, all abdominal MDCT being performed on a supine patient. Clinically, most patients present with acute or subacute abdominal pain. The pain may be to the left or right side of the midline based on the side of omental involvement. Pain may localize to the upper or lower quadrant of the abdomen, simulating acute appendicitis (66%) or cholecystitis. In female patients, the entity can also mimic gynecologic problems. The physical findings are variable but usually there is tenderness in the right side of the abdomen, predominantly at the right lower quadrant. Physical examination usually elicits localized tenderness with or without a palpable “mass”. Temperature is usually normal or slightly raised. Occasionally, the WBC count may be elevated. Therefore, clinically, omental infarction is difficult to be distinguished from appendicitis, cholecystitis, or adnexal problems (1, 2, 19, 20). The histological appearance of omental infarction differs with the duration of insult. Initially, hemorrhagic infarction with fat necrosis is seen, followed by infiltration by lymphocytes, histiocytes, and finally, fibroblasts, resulting in fibrosis and scar formation (19, 20, 26). The traditional classification of omental infarction without (primary infarction) or with (secondary infarction) torsion is clinically irrelevant because clinical findings imaging prognosis and treatment are the same (19, 20, 27). Before the advent of cross sectional imaging, segmental infarction was rarely diagnosed before surgery. Sonographically the classical presentation (1, 2, 19, 27, 28) consists of a solid, non-compressible, painful and moderetaly hyperechoic hyperattenuating mass in the vicinity of other abdominal structures. The lesion is typically found under the abdominal wall and covering the right colon (Fig. 12). On CT the presentation is also that of a well circumscribed fatty

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Fig. 9. — The normal falciform ligament is usually not visible unless surrounded by pneumoperitoneum (A, B, D) or ascitis (C). Lipomatous appendage are commonly hanging to the falciform ligament (white arrow onA-D). Sagittal US (E) and axial CT view (F) of a surgically proven infarcted lipomatous appendage of the falciform ligament found in a 25 year-old female presenting with epigastric pain. During ultrasound the small painful massa didn’t move with the intestinal structures (white asterisk) proving its parietal fixation. It was situated just under the right rectus muscle. On CT the lipomatous necrotic massa (white arrows) was situated just near the ligamentum teres (black arrow); TC = transverse colon.

Fig. 10. — Classical sagittal schematic anatomy of the greater omentum (GO) and peritoneum compartments. The vertical hanging portion (black arrow) of the greater omentum is constituted by the fusion of the four layers of the inferior recess of the bursa omentalis. Corresponding sagittal MDCT VR view (B) of the GO in a 45 year-old female. Anteroposterior VR view (c) of the same GO illustrating the anatomy of the veins (which are essential for the CT identification of the GO) comprising main left (white arrowhead) and right (black arrowhead) omental veins, a variable amount of intermediate vertical veins (small arrows) and the arch of Barkow (black arrow) a frequently well distinguishable anastomosis between left and right omental veins.

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Fig. 11. — Details of the prehepatic subphrenic projection of the right portion of the GO in a 55 year old male. This sagittal MPR view (A) shows the prehepatic projection of the omentum (star). Right upper quadrant ultrasound (B) demonstrates the hepatic omental covering (white arrows) that induces linear artefacts disturbing the homogeneity of the liver during scanning. Selected VR (C) and sagittal oblique MIP view (D) illustrate the “crooking” of the epiploic vessels (black arrows) under the falciform ligament (white arrowhead). This “crooking” could favour infarction of the right portion of the GO.

Fig. 12. — MDCT VR views (A, B) illustrating the subphrenic projection of the right portion of the GO (white arrow), an anatomic variant spontaneously found in 32% of the male population. This variant induces a severe “crooking” of numerous omental vessels under the falciform ligament (white arrowheads) and may contribute to explain the fact that omental infarction are more common in males and on the right. Axial (C) and sagittal oblique MPR (D) views of a typical case of right sided infarction of the right greater omentum (white arrow). The peritoneum is clearly inflamed (black arrowhead) and it explains the clinical pain. US (E) and axial CT (F) of another similar case (white arrow) with massive thickening of the peritoneum (black arrowhead). Both patients were treated conservatively.

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Fig. 13. — Axial (A) , coronal oblique (B) MPR views and selective VR view (C) of a typical case of right segmental infarction of the GO in a 60-year-old man. The lesion measures 4 x 4 cm and the vessels of the right portion of the GO are walking under the ligamentum teres of the falciform ligament (black arrow). Another case (D-F) of right segmental infarction (white arrows) of the GO in a 65-year-old female. Dense and probably thrombosed prominent veins are clearly seen (black arrowhead). These two patients were successfully treated conservatively.

B Fig. 14. — Coronal oblique (A) and axial (B) MPR views of a typical case of right segmental infarction (white arrow) of the GO in a 40-year-old man. The typical lesion measures 6 x 7 cm and contains irregular hemorrhagic foci and is surrounded by inflammatory peritoneum. Global selective VR view (C) of the greater omentum illustrating the right segmental infarction (white arrow). Axial oblique MIP view (D) and focused VR view (E) demonstrating a typical whirl of the epiploic vessels (white arrowheads) proving that the infarction was due to segmental torsion of the omentum. The patient was successfully treated conservatively.

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Fig. 15. — In this 50 year old patient presenting with medial subphrenic epigastric pain, axial (A), sagittal (B) and coronal (C) MPR views demonstrate the unusual segmental infarction of a portion of the free edge of the GO (white arrow). Volume rendering view (D) reveals that a complete coronal luxation of the GO has produced projecting its free edge in the subphrenic epigastric area. The displacement of the venous arch of Barlow illustrates the luxation (black arrow). White arrowhead = falciform ligament.

A D

Fig. 16. — Massive infarction of the nearly entire greater omentum (GO) found in a 73 year old patient after total gastrectomy. During surgical dissection numerous epiploic vessels were clipped. In the postoperative period the patient developed diffuse and heavy abdominal pain. Coronal (A) and axial (D) MPR views demonstrate a diffusely heterogeneous swollen and dedifferentiated swollen GO (white arrows) intermingled with necrotic fluid collections. The recovering peritoneum was sharply thickened (black arrows). Selective VR view (B) of the necrotic GO clearly shows the row of surgical clips (white arrowheads) responsible of the necrosis. The patient was treated conservatively. Abdominal CT return to normal in two months. The only consequence was a severe atrophy of the GO (E) when compared with the preoperative CT (C).

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★

★ ★ ★ ★

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Fig. 17. — Selective volume rendering (A) and axial oblique (B) MPR views of the normal lesser omentum. This fatty ligament (white star) inserts along the lesser curvature of the stomach (black star) and its peripheral border contains the left and right gastric vessels (white arrowheads). Its right free edge contains the hepatic vessels (black arrow). A rare case of lesser omentum (white star) infarction diagnosed in a 72-year old obese woman (A, B). Transversal US view (C) of the epigastric area shows a 5 x 4 x 3 cm painful, incompressible hyperechoic mass (white arrows). Coronal oblique (E), axial (D) and sagittal (F) MPR views confirm that the inflammatory mass corresponds to the infarcted lesser omentum. The clinical evolution was spontaneously favourable.

inflammatory mass, surrounded by normal viscera, circumscribed or covered by an inflammatory peritoneum and containing hyperechoic streaks probably corresponding to fibrous band and/or dilated thrombosed veins (1, 2, 19, 26-29) (Fig. 1216). Integrity of the adjacent organs eliminates the diagnosis of inflammatory fat secondary to more classical conditions such as diverticulitis, appendicitis, cholecystitis and Crohn disease. In rare cases an associated thickening of the transverse colon at the level of the insertion of the infarcted GO may be seen (19, 30). The presence of concentric linear streaks at the level of the torsion site is considerated as pathognomonic for an omental torsion but this sign as been extremely rarely described (2, 30-33). Thanks to its high capabilities of millimetric MPR, MDCT would probably be able to better demonstrate torsion of epiploic vessels (Fig. 14). Because of the good prognosis and spontaneous favourable evolu-

tion is most cases, follow-up studies are not systematically performed and in the very rare cases in which follow-up was available, complete resolution on inflammatory changes of both omentum and peritoneum was documented (2) (Fig. 16). Finally very rare cases of traumatic omental infarction (34, 35) (Fig. 19) and of twisting and infarction of the entire greater omentum have also sporadically been reported (36). It is well now recognized that the diagnosis of IFFI is safer with CT than with US, not only because the signs are more consistent and specific but also because CT generally definitively more safely excludes other mimicking or associated acute inflammatory abdominal conditions (1, 28). Lesser omentum The lesser omentum, which is a combination of the gastrohepatic and hepatoduodenal ligaments, connects the lesser curvature of the stomach and proximal duodenum

with the liver and covers the lesser sac anteriorly. This frontal peritoneal meso is constituted of two folds -anterior and posterior- and four borders hepatic, gastric, superior and a free right border-. The thickness is variable being slim in the middle area near the gastric insertion (pars flaccida), thicker in the oesophageal superior portion (condensed pars containing vessels) and in the right duodenal portion (duodeno-hepatic pars). The left portion (or gastrohepatic ligament) contains the left gastric vessels and left gastric lymph nodes and the right portion (or hepatoduodenal ligament) contains the portal vein, hepatic artery, extrahepatic bile duct, and hepatic nodal group (16, 37, 38). Primary masses or neoplasms of the lesser omentum are rare and include benign tumors (lymphangioma, neurogenic tumor, teratoma) and malignant neoplasms (liposarcoma, malignant gastrointestinal stromal tumor). Almost all of these

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Fig. 18. — Sagittal (A), axial (B), coronal (C) and oblique (D) MPR views of the epigastric area obtained in a 54-year-old patient presenting with unusual epigastric pain amplified during deep inspiration. Ultrasonography (not illustrated) was uncontributive but unenhanced MDCT revealed oedema and inflammatory changes of the anteroinferior portion of the lesser omentum. A segmental infarction of the lesser omentum was diagnosed. The evolution was sponteanously resolutive in a few weeks.

Fig. 19. — Unusual case of traumatic IFFI of the greater omentum diagnosed in a 70-year-old obese man. The patient was admitted with abdominal pain after a car accident during which he had received the steering wheel in the abdomen. Axial view (A) coronal oblique (B, C) and right and left sagittal (D, E) MPR views demonstrate foci of fat necrosis of the greater omentum (white arrows).

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potential complications such as abscess formation or adhesions are minimised. These arguments are questionable and controversial (27, 44). Unenhanced CT has been proposed in obese children who are more prone to present idiopathic omental infarction and in whom the diagnosis of appendicitis is clinically and sonographically invariably more difficult to establish (Fig. 20).

Fig. 20. — A rare case of segmental infarction of the GO (A-C) diagnosed in a 10-yearold obese boy: sagittal US view of the right flank (A) shows a 6 x 4 x 3 cm painful and incompressible precolic hyperechoic mass (white arrows). Corresponding sagittal oblique (B) and coronal (C) MPR CT views clearly identify a segmental infarction of the GO. Axial (D) and sagittal US (E) view and corresponding axial CT view (F) of a typical paediatric epiploic appendagitis (white arrow) of the right colon diagnosed in a 8-yearold boy. In the two cases the evolution was spontaneously favourable under medical treatment and the typical imaging findings revealed of primordial importance to exclude appendicitis and avoid unnecessary surgery.

tumors have variable and nonspecific CT features (16, 37, 38). A review of the medical literature (Medline) also essentially reveals the implication of the lesser omentum in metastatic disease (lymphoma, lung and oesogastric tumours), portal hypertension (varicose) and mechanical hernias through the hiatus of Winslow. Except for the location in the epigastric area, the rare reported cases of infarction of the lesser omentum presented with extremely similar findings in terms of clinical presentation, laboratory tests, US and CT findings with other reported IFFI cases (Fig. 17, 18). The differential diagnosis was to be made with gastro-duodenal ulcus disease and pancreatitis (37, 38). Pediatric cases AEA is generally found mostly in adults but about 15% of patients presenting with segmental infarction of the essentially right portion of the GO may be children (27, 28, 39, 40) and boys are affected twice as frequently as girls (Fig. 20). Like in adults the precise aetiology remains

controversial but obesity is a predisposing factor. Clinical and imaging features are the same as for adults. Notwithstanding the fact that the differential diagnosis of segmental omental infarction in children essentially concerns appendicitis and therefore more restricted than in adults, this clinical entity remains difficult to diagnose and in the most recent paediatric surgical papers surgery continues to be proposed as the treatment of choice (27, 39, 41, 42). There are several reasons to explain this discrepancy: firstly appendicitis remains the cardinal diagnosis in children presenting with acute right iliac fossa symptoms and in most cases the decision to perform appendicectomy remains predominantly based on clinical signs only. Secondly for a justified question of radioprotection, US remains the primary imaging method in children and although specific in the diagnosis of omental infarction it has been shown to be not as sensitive as CT and extremely operator dependant (43). Surgeons also justify that the child’s symptoms resolve rapidly after surgery and that

Bibliography 1. van Breda Vriesman A.C., Lohle P.N., Coerkamp E.G., Puylaert J.B.: Infarction of omentum and epiploic appendage: diagnosis, epidemiology and natural history. Eur Radiol, 1999, 9: 1886-1892. 2. Barbier C., Pradoura J.M., Tortuyaux J.M., et al.: Imaging of Segmental Infarction of the Greater Omentum: Diagnostic Findings and Pathophysiological Considerations. J Radiol, 1998, 79: 1367-1372. 3. Singh A.K., Gervais D.A., Hahn P.F., Rhea J., Mueller P.R.: CT Appearance of Acute Appendagitis. AJR, 2004, 183: 1303-1307. 4. Ghabremani G.G., White E.M., Hoff F.L., et al.: Appendices epiploicae of the colon: radiologic and pathologic features. Radiographics, 1992, 12: 59-77. 5. Sand M., Gelos M., Bechara F.G., et al.: Epiploic appendagitis – clinical characteristics of an uncommon surgical diagnosis. BMC Surgery, 2007, 7: 11. 6. van Breda Vriesman A.C., de mol van Otterloo J.C., Puylaert J.B.: Epiploic appendagitis: an underestimated selflimiting acute abdominal condition. Ned Tijdschr Geneeskd, 2003, 147: 1113-1118. 7. Danielson K., Chemin J.R., Amberg J.R., Goff S., Durham J.R.: Epiploic appendagitis: CT characteristics. J Comput Assist Tomogr, 1986, 10: 142-143. 8. Rioux M., Langis P.: Primary epiploic appendagitis: clinical, US, and CT findings in 14 cases. Radiology, 1994, 191: 523-526. 9. Rao P.M., Wittenberg J., Lawrason J.N.: Primary epiploic appendagitis: evolutionnary changes in CT appearance. Radiology, 1997, 204: 713-717. 10. Lloyd T.: Primary torsion of the falciform ligament: computed tomography and ultrasound findings. Australas Radiol, 2006, 50: 252-254. 11. Coulier B., Broze B., Mailleux P., Maldague P.: Small-bowel internal herniation through the falciform ligament: 64 row-MDCT diagnosis. Emerg Radiol, 2009, 28. 12. Brock J.S., Pachter H.L., Schreiber J., Hofstetter S.R.: Surgical diseases of the falciform ligament. Am J Gastroenterol, 1992, 87: 757-758. 13. Kakitsubata Y., Nakamura R., Shiba T., et al.: Lipoma of the falciform liga-

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35. Ramos C.T., Sammartano R.: Laparoscopic omentectomy for omental infarction after bicycle handlebar injury. J Laparoendosc Adv Surg Tech A, 2008, 18: 327-329. 36. Coppin T., Lipky D.: Twisting and infarction of the entire greater omentum managed by laparoscopy: a report of two cases. Acta Chir Belg, 2006, 106: 215-217. 37. Coulier B., Van Hoof M.: Intraperitoneal fat focal infarction of the lesser omentum: case report. Abdom Imaging, 2004, 29: 498-501. 38. Coulier B.: A new case of intraperitoneal fat focal infarction (IFFI) of the lesser omentum. Eur Radiol, 2006, 16: 954-955. 39. Sakkelaris G., Stathopoulos E., Kafousi M., et al.: Primary idiopathic segmental infarction of the greater omentum: two cases of acute abdomen in childhood. J Pediatr Surg, 2004, 39: 1264-1266. 40. Van Kerkhove F., Coenegrachts K., Steyart L., et al.: Omental infarction in chilhood. JBR-BTR, 2006, 89: 199-200. 41. Grattan-Smith J.D., Blews D.E., Brand T.: Omental infarction in pediatric patients: sonographic and CT findings. AJR, 2002, 178: 15371539. 42. Varjavandi V., Lessin M., Kooros K., et al.: Omental infarction : risk factors in children. J Pediatr Surg, 2003, 38: 233-235. 43. Schlesinger A.E., Dorfman S.R., Braveman R.M.: Sonographic appearance of omental infarction in children. Pediatr Radiol, 1999, 29: 598-601. 44. Fragoso A.C., Pereira J.M., EstevaoCosta J.: Nonoperative management of omental infarction: a case report in a child. J Pediatr Surg, 2006, 41: 17771779.

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AN UNUSUAL CAUSE OF PELVIC HEMORRHAGE: MULTIDETECTOR CT DIAGNOSIS OF INFERIOR MESENTERIC VEIN INJURY D. Karaosmanoglu, M. Boge, E. Akpinar, M. Karcaaltincaba1 Pelvic trauma can lead to uncontrollable bleeding and even death. Although significantly decreased with the application of novel treament modalities and the use of state-of-the-art imaging equipment, pelvic trauma and subsequent bleeding remains to stay as a major source of morbidity and mortality. In this case we present a patient suffering from pelvic bleeding from the inferior mesenteric vein due to sigmoid mesocolon injury. Similar finding has not been reported as an isolated source of pelvic hemorrhage. We also propose that the routine use of reformatted images obtained with multidetector CT scanners in patients with hemoperitoneum may be a highly useful adjunct for the correct identification of the source of hemorrhage. Key-words: Pelvic organs, hemorrhage – Veins, mesenteric – Veins, injuries.

Pelvic hemorrhage is a wellknown clinical phenomenon, most commonly seen after pelvic trauma, freqently associate with the fractures of the osseous ring of the pelvis. In patients with pelvic fracture it is of utmost importance to look for any signs of hemorrhage. The source of bleeding in the affected patients is generally the venous structures, however arterial structures may also be the culprit abnormality in these patients. In this paper, we present and discuss the imaging findings of a patient with pelvic hemorrhage from inferior mesenteric vein (IMV) due to sigmoid mesocolon injury. To the best of our knowledge, IMV as a source of pelvic bleeding has not been reported before.

Fig. 1. — Axial contrast-enhanced MDCT of the patient reveals inferior mesenteric vein at the level of pelvic inlet (arrow). Also note the hemorrhage in pelvis.

Case report Thirty year-old male patient admitted to the emergency department after a car accident where he was the driver. At the admission the patient was fully conscious and welloriented. The blood pressure from the left arm was 100/60 mm Hg. The patient was primarily complaining from excruciating diffuse abdominal and facial pain. The physical examination could not be systematically performed and brief examination of the abdomen revealed diffuse tenderness and an adequate examination could not be realized. The examination of the face was also found to be suggestive for several

fractures by the emergency physician. Then the patient was transferred to the radiology unit of emergency room for CT imaging (by 4MDCT, Siemens Medical System) of head, thorax and abdomen. The patient was found to have several fractures at the fascial bones as well as diffuse bilateral lung contusion. Abdominal imaging was the most striking among these examinations, disclosing diffuse intraperitoneal free air and pelvic free fluid sugges-

From: Hacettepe University School of Medicine, Department of Radiology. Ankara, Turkey. Address for correspondence: Dr M. Karcaaltincaba, M.D., Hacettepe University School of Medicine, Department of Radiology. Sihhiye 06100, Ankara, Turkey. E-mail: musturayk@yahoo.com

tive of hemorrhage and perforation (Fig. 1). No lacereation or bleeding was detected in the abdominal solid organs. Coronal and sagittal reformatted MDCT images were reconstructed from raw data, revealed the IMV as the source of bleeding (Fig. 2). Subsequently the patient was transferred from the CT suit to the operating room. At the surgery, the patient was found to have focal lacerations at the sigmoid colon and ileum. He was finally treated with limited sigmoid colon resection and primary repairing of the small bowel. The pelvic hemorrhage was also detected perioperatively and the bleeding vessels were cauterized. The post-operative course was uneventful and he was also operated for his facial fractures several days after the abdominal surgery.

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B A Fig. 2. â&#x20AC;&#x201D; Coronal (A) and sagittal (B) curved planar reformatted MDCT images clearly demonstrate inferior mesenteric vein (arrowhead) and injury (white arrow) and increased density in the sigmoid mesocolon consistent with hemorrhage (black arrows). The interruption of the inferior mesenteric vein at the level of pelvic hemorrhage can also be nicely depicted (white arrow).

Discussion Pelvic trauma and subsequent hemorrhage remain to be a significant contributor to the mortality and morbidity of trauma victims. The complex nature of these injuries may pose challenging problems to the attending emergency physicians and surgeons, and the radiologists as well. Mortality rates due to pelvic trauma and bleeding have dramatically decreased secondary to prompt and more concise diagnostic and treatment modalities (1-3). Pelvis is a highly vascularised portion of the abdomen comprising several arteries and veins, where iliac vessels are the leading ones. Hematoma after pelvic trauma, particularly with associated osseous fractures, may reach to substantial sizes that may jeopardize the hemodynamic stability of the trauma victims. Several underlying pathophysiological processes may play role as the source of bleeding, namely, the arteries, veins and the bony structures. Arterial bleeding is the result of interruption of the vessel wall

integrity, while the venous bleeding is particularly from the posterior venous plexus with the same pathophysiology. Bleeding from cancellous bone may also give rise to lifethreatening hemodynamic instability (4). Considering the differing treatment modalities in various clinical scenario, correct identification of the source of the bleeding may be highly useful adjunct for choosing the ideal treatment. Although arterial bleeding is more frequent in life threatening bleeding, venous structures are reported to be the commonest source (90%, mostly from presacral and prevesical veins), while arterial bleeding is much less common (10%, trunk or distal lesions) (5, 6). However, it must be kept in mind that all three mentioned pathophysiologic mechanisms may act at the same time during the process. Arterial injuries are best managed by endovascular embolisation, while venous bleeding are generally tried to handle with some form of tamponade. It is generally believed that high energy trauma with the loss of pelvic integrity is the

most risky occurrence for a massive pelvic hemorrhage, however this assumption has not been confirmed by some other reports (4). In this manuscript, we tried to explain the role of CT and the isotropic reformatting ability of new generation multidetector CT equipment in the correct diagnosis of the source of pelvic hemorrhage. Interestingly, this patient did not have any imaging or clinical evidence of disruption of pelvic osseous integrity and the laceration of inferior mesenteric vein probably occurred due to accleration-deceleration injury. We think that the application of reformatted images may be highly useful for the depiction of the injured vessel and may promptly facilitate the application of adequate and relevant application of treatment. This case is also unique considering the lacerated vessel. Inferior mesenteric vein, to the best of our knowledge, has not been reported before as the only source of pelvic bleeding. The use of reformatted image was a strong contributor for

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reaching the correct diagnosis in the presented subject and we think that it will be highly useful to use them on a routine basis in order to identify the correct site of vascular injury in trauma victims having pelvic hemorrhage. With the development of highly versatile and easy-to-apply softwares these images can also be created even before the departure of the patient from the imaging suit and the physicians in charge would be effectively and promptly oriented to the main pathology. With the correct identification, the treatments will be right to the target and the

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invaluable time would not be lost in the triage and treatment process. References 1.

Agolini S.F., Shah K., Jaffe J., Newcomb J., Rhodes M., Reed J.F. 3rd.: Arterial embolisation is a rapid and effective technique for controlling pelvic fracture haemorrhage. J Trauma, 1997, 43: 395-399. 2. Barlow B., Rottenberg R.W., Santulli T.V.: Angiographic diagnosis and treatment of bleeding by selective embolisation following pelvic fracture in children. J Pediatr Surg, 1975,10: 939-942.

3. Perez V., Hughes TM, Bowers K.: Angiographic embolisation in pelvic fracture. Injury, 1998,29: 187-191. 4. Dyer G.S.M., Vrahas M.S.: Review of pathophysiology and acute management of haemorrhage in pelvic fracture. Injury, 2006, 37: 602-613. 5. Gansslen A., Giannoudis P., Pape H.C.: Hemorrhage in pelvic fracture: who needs angiography? Curr Opin Crit Care, 2003, 9: 515-523. 6. Ben-Menachem Y., Coldwell D.M., Young J.W., Burgess A.R.: Hemorrhage associated with pelvic fractures: causes, diagnosis, and emergent management. AJR, 1991, 157: 1005-1014.

CLASSIFIED SERVICES FRANCE, région Sud-Ouest Radiologue installée à 10 km du centre d’une ville universitaire du sud ouest - France recherche associé(e): exercice libéral – radio conv. numerisée – écho – séno – ostéodensitométrie– accès scan- IRM dans GIE universitaire. Renseignements: 00-33-6 08 37 79 68

JBR–BTR, 2010, 93: 189-192.

POST-TRAUMATIC HEPATIC ARTERIAL PSEUDOANEURYSM AND ARTERIOPORTAL SHUNT J. Maes1, O. d’Archambeau1,2, A. Snoeckx1, B. Op de Beeck1, M. Voormolen1, P.M. Parizel1 The authors report the case of a 21-year-old man who suffered from a blunt abdominal trauma. Initial imaging revealed a liver laceration at the right lobe, a perirenal hematoma of the right kidney and a hematoma of the right adrenal gland. Follow-up MDCT-scan on day 10 after admission showed at the arterial-phase contrast-enhanced study perfusion alterations and two hepatic pseudoaneurysms. The diagnosis of pseudoaneurysm was confirmed and treated angiographically with superselective coil embolization. A follow-up CT-scan on day 17 showed at a nontreated area an arterioportal shunt and a wedge-shaped transient hepatic parenchymal enhancement. This was confirmed angiographically and subsequently treated with coil embolization. Key-words: Liver, angiography – Aneurysm, hepatic.

A liver hematoma is a common finding after blunt abdominal trauma. Radiological follow-up is important to demonstrate its resorption or to detect its possible complications. Multidetector computed tomography (MDCT) is the imaging technique of choice for hepatic trauma and has had an enormous impact on the detection and management of liver injuries. A triphasic scan should be performed. On noncontrast scans hematomas appear hyperdense or hypodense relative to normal hepatic parenchyma depending on the nature, as clotted (40-70 HU) or unclotted blood (20-40 HU). Active hemorrhage is identified as contrast extravasation on arterial phase contrast-enhanced CT. Delayed contrast images in the late venous phase after 2 minutes show the persistence of high density with active bleeding compared to the density of surrounding vessels and a washout of contrast attenuation in pseudoaneurysms showing the same density as surrounding vessels. Hepatic arterial pseudoaneurysms as well as arterioportal shunts are rare but potentially life-threatening complications. We briefly discuss the imaging findings, the endovascular management and the outcome of both entities in the setting of blunt abdominal trauma. Case report A 21-year-old man was admitted at our hospital after falling from a bridge. He suffered from persistent

pain in the right upper quadrant. Clinical examination showed a tender abdomen. Initial monophasic MDCT-scan revealed a liver laceration at the right lobe, a perirenal hematoma of the right kidney and a hematoma of the right adrenal gland (Fig. 1A). Free abdominal fluid with high attenuation values (45 HU) confirmed a haemoperitoneum. The patient was referred to the intensive care unit for observation and since he remained haemodynamically stable, he was further treated conservatively. Follow-up MDCT-scan on day 10 after admission showed at the late arterial-phase perfusion alterations in the right liver lobe as well as two focal round hyperdense lesions in the area of the liver laceration (Fig. 1B-C), making the diagnosis of post-traumatic pseudoaneurysms of the hepatic artery very likely. The diagnosis of one pseudoaneurysm was confirmed angiographically (Fig. 1D) and was successfully embolized by superselective coiling (Fig. 1E), using four Cook Nester microcoils (2x 10 mm-14 cm and 2x 8 mm-14 cm coils). Initial arteriographic control by the endovascular catheter showed a complete embolization of the pseudoaneurysm, with preservation of other intrahepatic branches. The second lesion could not be confirmed angiographicallly, probably due to vascular spasms. A follow-up CT-scan on day 17 (Fig. 2A) revealed a persistent and even more prominent wedge-shaped, early transient segmental parenchymal enhance-

From: 1. Dept of Radiology, University Hospital Antwerp, Edegem, 2. Dept of Radiology, Sint-Augustinus Hospital, Wilrijk, Belgium. Address for correspondence: Dr J. Maes, M.D., Department of Radiology, University Hospital Antwerp, Wilrijkstraat 10, B-2650 Edegem, Belgium. E-mail: joachim.maes@uza.be

ment of the posterior part of the right liver lobe due to a shunt between a branch of the right hepatic artery and the right portal vein. The arterioportal shunt was confirmed angiographically (Fig. 2B) and treated successfully (Fig. 2C) by means of superselective embolization with multiple Hilal coils (multiple 3 mm3 cm and 2x 4 mm-2 cm coils). The patient left the hospital symptomfree the day after and a follow-up CTscan two months later showed a complete recovery. Discussion In the past decade, there has been a shift from routine surgical to nonsurgical management of blunt liver injuries (1). The general use of MDCT in the diagnosis and management of blunt liver trauma is mainly responsible for this change. CT can accurately diagnose parenchymal injuries and exclude surgical lesions such as bowel or pancreatic injuries. Previous studies showed that 86% of liver injuries stopped bleeding by the time of surgery and that up to 67% of all exploratory celiotomies performed for blunt abdominal trauma were non-therapeutic (2). Therefore, nonsurgical management has become the standard care in haemodynamically stable patients with blunt liver trauma. The nonsurgical approach requires fewer blood transfusions, patients have less abdominal sepsis and a better survival rate (1). Hepatic lacerations and subcapsular or intraparenchymal hematomas are the most common type of parenchymal liver injury. Less common, active haemorrhage and major hepatic venous injuries can be seen following blunt liver trauma; both of these lesions can be life-threatening and require immediate treatment. Periportal low attenuation and a flat

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D Fig. 1. â&#x20AC;&#x201C; A: Initial monophasic MDCT-scan shows free abdominal fluid, a liver hematoma and a right adrenal gland hematoma. B-C: Follow-up scan on day 10, arterial-phase contrast image and MIP showing early enhancement at the right liver lobe and two hepatic pseudoaneurysms. D-E: Digital subtraction arteriography confirming one arterial pseudoaneurysm in the right liver lobe before and after hyperselective embolization with microcoils.

E IVC can also be seen as a direct complication of blunt liver trauma. As more patients with complex liver injuries are treated nonsurgically, the prevalence of delayed complications at follow-up CT has

increased (5-23%) (2). These posttraumatic complications include delayed haemorrhage, abscess, post-traumatic pseudoaneurysm, haemobilia and biliary complications such as biloma and bile peritonitis.

Interventional radiology plays a major role in the initial management of such complications (3). In the context of our case report, we will focus on post-traumatic hepatic arterial pseudoaneurysms (HAP) and arterioportal shunts (APS) or fistulas. HAP is a rare complication of blunt abdominal trauma with a reported prevalence of 1% (4). Symptoms can vary from a silent incidental finding to an acute lifethreatening haemorrhage caused by rupture. On imaging studies it typically presents at early phase

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B Fig. 2. â&#x20AC;&#x201C; A: Follow-up MDCT on day 17 revealing a wedgeshaped early transient segmental parenchymal enhancement at the posterior part of the right liver lobe due to a rather large arterioportal shunt between a branch of the right hepatic artery and the posterior branch of the right portal vein. B-C: Selective angiography demonstrating the arterioportal fistula (APF) in the right liver lobe (B) and a post-procedure image (C) after successful embolization of the APF and HAP.

C contrast-enhanced CT as a round, focal lesion with high attenuation that is almost identical to major arterial structures. Selective angiography was the gold standard for diagnosing HAP. Tobben et al. (5) reported a sensitivity for HAPs of 100%, 67% and 33% by SA, CT and duplex sonography. The sensitivity of the newer generation US and MDCT is higher so that these non-invasive techniques are today the first choice if HAP is suspected. SA may also reveal active bleeding and/or anatomic variants. Treatment of choice is hepatic artery embolization, which has a high success rate and can be performed immediately after diagnostic arteriography (6). The embolization should be as selective as possible in order to decrease the risk of ischemia and the risk of collateral/retrograde flow from branches distal to the point of embolization.

Mostly microcatheters and microcoils are used, but different materials have been used successfully over the years, including thrombin injection, covered stents, glue and gelfoam. Endovascular treatment options depend on lesion location and size (7). Embolization of the afferent artery can be used in pseudoaneurysms that arise from a single supplying artery without other collateral feeders, whereas in case of visceral arteries with well-established collateral supply, embolization of both proximal and distal branches to the pseudoaneurysm is mandatory in preventing backflow from the collateral circulation. A direct embolization delivering coils or glue into the sac can also be performed if the aneurysmal neck is narrow. Stent-graft placement represents another option to exclude the pseudoaneurysm in case of a wide

neck, reduced arterial tortuosity and large-diameter arteries (7). APS or fistula is also a rare complication of blunt abdominal trauma. Recognition is important because it may cause life-threatening portal hypertension if left untreated. Posttraumatic APSs are usually large and single to few in number. The mechanism of arterioportal shunting is most likely a direct hepatic artery to portal vein communication. APS could be the only manifestation of blunt liver trauma. The clinical spectrum of presentation ranges from symptom-free individuals to patients with severe hypertension, but the overall prognosis is good. The characteristic imaging findings of APSs are a wedge-shaped transient hepatic parenchymal enhancement and a homogeneous high attenuation of the portal vein branches at the arterial phase, and isoattenuating or slightly hyperattenuating areas during the portal venous phase. Arteriography may be required to establish the angioarchitecture of the APS. Treatment of choice is (super)selective transarterial embolization. Recently, a classification with therapeutic implications has been proposed by Guzman et

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al. (8). A detailed radiologic evaluation can lead to differentiate small peripheral intrahepatic APSs (type 1 â&#x20AC;&#x201C; needle injuries) and large central APSs (type 2). Congenital APSs (type 3) are diffuse and intrahepatic and these are the most difficult to manage. Type 1 usually resolves spontaneously, whereas type 2 can cause severe complications including portal hypertension and hepatic parenchymal changes. Therefore, this latter type of APSs always needs treatment, preferably transcatheter embolization. In conclusion, we can state that both HAP and APS are rare, but possible life-threatening and often late complications of blunt abdominal trauma. They show distinct imaging findings on MDCT and angiography. In most cases, they both can be

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treated successfully by (super-)selective embolization. References 1.

Yoon W., Jeong Y.Y., Kim J.K., et al.: CT in blunt liver trauma. Radiographics, 2005, 25: 87-104. 2. Pachter H.L., Knudson M.M., Esrig B. et al.: Status of nonoperative management of blunt hepatic injuries in 1995: a multicenter experience with 404 patients. J Trauma, 1996, 40: 3138. 3. Galeon M., Goffette P., Van Beers B.E., Pringot J.: Post-traumatic intrahepatic pseudoaneurysm: diagnosis with helical CT angiography and management with embolization. J Belge Radiol, 1997, 80: 287-288. 4. Kim H.J., Kim K.W., Kim A.Y. et al.: Hepatic artery pseudoaneurysms in adult living-donor liver transplantation: efficacy of CT and Doppler

sonography. AJR, 2005, 184: 15491555. 5. Tobben P.J., Zajko A.B., Sumkin J.H., et al.: Pseudoaneurysms complicating organ transplantation: roles of CT, duplex sonography, and angiography. Radiology, 1988, 169: 65-70. 6. Finley D.S., Hinojosa M.W., Paya M., Imagawa D.K.: Hepatic artery pseudoaneurysm: a report of seven cases and a review of the literature. Surg Today, 2005, 35: 543-547. 7. Basile A., Ragazzi S., Piazza D., Tsetis D., Lupattelli T., Patti M.T.: Hepatic artery pseudoaneurysm treated using stent-graft emplantation and retrograde gastroduodenal artery coil embolization. Eur Radiol, 2008, 18: 2579-2581. 8. Guzman E.A., McCahill L.E., Rogers F.B.: Arterioportal fistulas: introduction of a novel classification with therapeutic implications. J Gastrointest Surg, 2006, 10: 543-550.

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LEIOMYOMATOSIS PERITONEALIS DISSEMINATA IN A 50-YEAR OLD WOMAN: IMAGING FINDINGS A. Talebian Yazdi, K. De Smet, M. Antic, B. Ilsen, F. Vandenbroucke, J. de Mey1 Leiomyomatosis peritonealis disseminata (LPD) – or diffuse abdominal leiomyomatosis – is a very rare benign abdominal entity. Only a little more than 100 cases have been reported in the English literature since its first description in 1965. Middle aged female are typically affected and the clinical presentation is rather aspecific. The differential diagnosis between benign LPD and diffuse peritoneal carcinomatosis or abdominal disseminated malignancy represents the crucial diagnostic challenge that can only definitively be made through biopsy and histologic analysis. Multimodal imaging features (ultrasound, CT, MR and PET) of a case of LPD diagnosed in a 50-year old female are presented with review the literature. Key-word: Leiomyoma.

Uterine leiomyoma is a well known and common gynecological entity affecting women primarily in the 3rd through 5th decades of life. These benign tumors usually arise in the urogenital tract, but unusual locations have been described. Differentiation from malignant leiomyosarcoma is of great clinical importance. Histopathologically, the most important criterium is mitotic activity (1-2). Extra-uterine leiomyoma is a rare but well known entity with the lung, small bowel, skin and oesophagus being the most common locations. Although the classical leiomyoma of the uterus has easily distinguishable radiological features, unusual locations of leiomyoma can confront the radiologist with a diagnostic dilemma. This manuscript reports on a case of diffuse peritoneal leiomyomatosis, with illustartion of the key radiological and histopathological features.

Case report A 50-year-old, female patient presented at the emergency department complaining of vague abdominal discomfort in the back, radiating to the left lower quadrant. Routine clinical and laboratory work-up led to no specific diagnosis. Ultrasonography of the abdomen showed a normal aspect of the solid abdominal organs. Dispersed in the abdominal cavity, numerous nodules with varying size were detected (Fig. 1). These solid nodules were hypoechoic with little vascularisation on color Doppler. A contrast enhanced abdominal CT demon-

B Fig. 1. — A: Grey scale US showing multiple solid nodules, randomly dispersed in the peritoneum. B: On color Doppler US the nodules shows low to moderate vascularisation.

From: 1. Department of Radiology, UZ Brussel, Brussels. Address for correspondence: Dr A. Talebian Yazdi, Dept. of Radiology, UZ Brussels, Laarbeeklaan 101, B-1090 Brussels, Belgium.

strated multiple nodules, located in the intra-, retro- and extraperitoneal cavity. The nodules demonstrated a heterogeneous uptake of contrast on

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C Fig. 2. â&#x20AC;&#x201D; Multi-phasic contrast enhanced CT demonstrates initial heterogeneous enhancement on the arterial (A) and venous phase (B, D), with a homogeneous contrast uptake on the late phase (C). D: Coronal MPR, venous phase.

the arterial and venous phase. On the late phase however a nearly homogenous uptake in the lesions was demonstrated (Fig. 2). The patient was scheduled for CTguided biopsy. The tentative histopathological diagnosis was leiomyoma, but malignant leiomyosarcoma could not be ruled out on basis of the biopsy. The tumor markers showed normal levels of BHCG, CEA and CA125 and on the PET-examination no tracer uptake was shown for the nodules. These results practically excluded malignancy. The patient was scheduled for a MRI of the abdomen. The nodules showed an intensity similar to smooth muscle (Fig. 3). On explorative laparatomy surgical specimens were taken for a more definite PA diagnosis. The PA report described no sign of necrosis, nor-

mal mitotic activity and no nuclear polymorphism, confirming the diagnosis of diffuse peritoneal leiomyomatosis. Discussion Leiomyomas of the urogenital tract are primarily benign disorders and reports on metastases from these tumors are infrequently encountered in the literature. These benign tumors of smooth muscle origin are more common in the urogenital tract while leiomyomatosis in unusual locations can pose a diagnostic challenge. Women in their reproductive age or using oral contraceptives are at risk for developing leiomyomas outside the urogenital tract. A hormonal influence has therefore been hypothesized (3). History of hysterectomy has also

been suggested to be associated with distant urogenital leimyomas. The time interval between hysterectomy and metastases can reach up to 20 years. Although the clinical presentation is nonspecific, symptoms such as chest pain, abdominal discomfort and dyspnea have been described. Usually these tumors arise in the genitourinary tract but may arise in or metastasize to nearly any anatomic site. In case of invasion of the peritoneal cavity the condition is called leiomyomatosis peritonealis disseminata or diffuse peritoneal leiomyomatosis (4). The exact pathophysiology of disseminated leiomyomatosis remains enigmatic. Local overgrowth of smooth muscle cells under hormonal influence has been hypothesized (5). Intra-abdominal deposition during surgery for a pri-

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oophorectomy leads to a good overall prognosis and survival rate. Conclusion Leiomyomatosis peritonealis disseminata is a very rare benign disorder affecting middle aged women. The differentiation from leiomyosarcoma is essential and requires imaging and histopathological workup. Knowledge of the main features is important for the radiologist in order to correctly diagnose this entity and prevent unnecessary and potentially harmful intervention.

References 1.

Fig. 3. â&#x20AC;&#x201D; MRI of the abdomen shows iso-intensity of the lesions with skeletal muscle (A). After Gadolinium injection there is heterogeneous enhancement in the early phase (B, 30 sec), gradually progressing to homogenous enhancement on the late phase (C, 90 sec).

mary urogenital leiomyoma is another hypothesis (6). Although a highly malignant leiomyosarcoma can be readily diagnosed histopathologically, the distinction between a leiomyoma and a low-grade leiomyosarcoma can be challenging. The latter entity must be ruled out regarding the evident clinical implications. Laparatomy and surgical biopsy are essential for a definitive diagnosis. In this paper we have reported a case of leiomyomatosis of the abdominopelvic cavity, first described in 1965 (3). This entity strongly mimics peritoneal metastasis. Knowledge of the imaging characteristics of this benign entity, therefore helps the radiologist to recognise this disorder, with peritoneal carcinomatosis being the most important differential diagnosis. Lymphoma, tuberculosis and mesothelioma are also other potential mimickers. Ultrasound character-

istics include homogenous hypoechoic, solid nodules with low to moderate vascularity (7). Contrast enhanced CT will reveal solid lesions dispersed in the abdominal cavity with heterogeneous contrast uptake in the arterial and venous phase, gradually progressing to a homogenous uptake in the late phase (8). Iso-intensity with skeletal muscle on T1 and T2 is the most important MRI feature. Administration of gadolinium reveals homogenous enhancement of the lesions in the late phase (9). On positron emission tomography (PET) the nodules show no uptake of FDG, whereas malignant lesions classically show avid FDG uptake. PET is therefore a key modality for the differentiation of LPD from malignant peritoneal disease. The treatment of LPD is generally surgical. Resection of the primary tumors, metastatic implants and

Silverberg S.G., Kurman R.J.: Tumors of the uterine corpus. Tumors of the Uterine Corpus and Gestational Trophoblastic Disease. Washington, DC: Armed Forces Institute of Pathology; 1991, 113-146. Atlas of Tumor Pathology; 3rd series, fascicle 3. Kempson R.L., Hendrickson M.R.: Pure mesenchymal neoplasms of the uterine corpus. Haines and Taylor Obstetrical and Gynecological Pathology. Edinburgh, Scotland: Churchill Livingstone, 1987, 411-456. Taubert H.D., Wissner S.E., Haskins A.L.: Leiomyomatosis peritonealis disseminata. Obstet Gynecol, 1965, 25: 561-574. Kaplan C., Bernirschke K., Johnson K.C.: Leiomyomatosis peritonealis disseminata with endometrium. Obstet Gynecol, 1980, 55: 119-122. Tavassoli F.A., Norris H.J.: Peritoneal leiomyomatosis (leiomyomatosis peritonealis disseminata): a clinicopathological study of 20 cases with ultrastructural observations. Int J Gynecol Pathol, 1982, 1: 59-74. Thian Y.L., Tan K.H., Kwek J.W.: Leiomyomatosis peritonealis disseminata and subcutaneous myoma - a rare complication of laparoscopic myomectomy. Abdom Imaging, 2009, 34: 235-8. Papadatos D., Taourel P., Bret P.M.: CT of leiomyomatosis peritonealis disseminata mimicking peritoneal carcinomatosis. AJR, 1996, 167: 475-476. Fulcher A.S., Szucs R.A.: Leiomyomatosis peritonealis disseminata complicated by sarcomatous transformation and ovarian torsion: presentation of two cases and review of the literature. Abdom Imaging, 1998, 23: 640-644. Singh G., Gordon-Harris L., Frazer G.B.: leiomyomatosis peritonealis disseminata â&#x20AC;&#x201C; diagnosis by sonography. Ind J Radiol Imaging, 2002, 12: 497-500.

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INTRACRANIAL GERM CELL TUMOR J. Kreutz1, L. Rausin1, E. Weerts1, M. Tebache1, J. Born2, C. Hoyoux3 Germ cell tumours represent about 3 to 8% of pediatric brain tumours. Occurrence of diabetes insipidus is common in the case of suprasellar germ cell tumors. The diagnosis may be advanced by MRI owing to the location and relatively univocal characteristics of the lesion signal. The existence of a bifocal mass developed in both suprasellar region and pineal zone is highly suggestive of a germinoma. The most important notion is to recognize that at the time of diabetes insipidus diagnosis in a child, the cerebral mass might be too small to be identified by MRI. In such patients, repeating imaging study should be obtained. Key-word: Brain neoplasms, in infants and children.

Case report A 12-year-old-girl was admitted at the emergency department because of areactive mydriasis associated with oculomotor paresis of the left eye. Six month earlier, she was explored by brain MR for hypotrophy and occurrence of diabetes insipidus. At this time, a suprasellar mass was evidenced and a biopsy was undertaken which led to the diagnosis of lymphocytic hypophysitis (Fig. 1). Actually, a new brain MR demonstrated a multifocal insult reaching both the suprasellar zone and the pineal gland (Fig. 2). On such an imaging basis, the previous diagnosis was revisited to finally conclude to the existence of an intracranial germ cell tumour.

A B

Discussion Differential diagnosis of the suprasellar masses in a child with diabetes insipidus includes several hypothesis including craniopahryngioma, germ cell tumour, Langerhans’ cell histiocytosis, lymphocytic hypophysitis and granuloma (sarcoidosis or tuberculosis) (1). However, our findings of an insult interesting simultaneously the suprasellar zone and the pineal region, reduce the field of pathological hypothesis. Morphology and localization of the multifocal process rather suggest the diagnosis of brain bifocal germinal tumour. On this basis, the biopsy specimen was revisited and confirmed the diagnosis of germinal tumour in spite of absence of blood tumoral markers. Germ cell tumours represent about 3 to 8% of pediatric brain

Fig. 1. — First MR examinationT1: enlargement of the pituitary stalk and the loss of the spontaneous hypersignal of the neurohypophysis (A). T2 hypersignal inside the pituitary stalk (B). Homogeneous enhancement on sagittal T1 + gadolinium (C).

tumours (2). Up to 60% of the pineal proliferations are germinoma. Almost 30% of these neoplasms develop in the suprasellar-hypothalamic region. Less common locations include the basal ganglia, C-P angle, cerebellum, corpus callosum and the spinal cord. Both suprasellar and

From: Department of 1. Medical Imaging, 2. Neurosurgery, 3. Pediatrics, CHR Citadelle, Liège, Belgium. Address for correspondence: Dr J. Kreutz, Dpt of Medical Imaging, CHR Citadelle Liège, B-4000 Liège, Belgium.

pineal gland involvement at the time of diagnosis represent 5%-10% of cases (2). Of germ cell tumours, about 65% are germinomas, 16% are teratoma, 6% are embryonal cell carcinoma, 4% are choriocarcinoma and 9% are mixed germinal tumour. The diagnosis may be advanced by MRI owing to the location and relatively univocal caracteristics of the lesion signal. The existence of a bifocal mass developed in both suprasellar region and pineal zone is highly suggestive of a germ-cell tumour and most commonly a ger-

INTRACRANIAL GERM CELL TUMOR â&#x20AC;&#x201D; KREUTZ et al

B Fig. 2. â&#x20AC;&#x201D; Second MR examinationT1 (A) and T2 (B): tumoral growth with extension to the supra-sellar region. T1 +gado reveals a pineal mass (C).

should be obtained within 3 to 6 months and, if still negative, next exploration should be conducted after another run of 3 to 6 months (4). Stereotactic biopsy is obviously indicated even if the specimen analysis remains hard to give a definetly ruling on diagnosis (5). Therapeutical protocol of germ cell tumours consists in chemotherapy followed by radiotherapy. Survival at 5 years of the germinoma is actually beyond 91% (2). Accordingly, our patient was submitted to a protocol based first on VP16, Ifosfamid and Mesna and secondly on carboplatin associated with VP16. This chemotherapy was finally followed by radiotherapy focused on the suprasellar lesion. Based on this cure, the ultimate MR showed a dramatic reduction in the volume of both the pituitary stalk and the pineal mass. References 1.

minoma (3). The imaging varies with histology. Germinoma are usually well-marginated tumours, either round or lobulated, that demonstrate iso to hyperintensity on T1WI and iso to hyperintensity on T2WI. A relatively hypointensity image on T2WI in a suprasellar or a pineal region in an adolescent is highly suggestive of such tumour. Enhancement is usually homogeneous but some internal hetero-

geneity is often seen in large germinomas (4). The lack of physiological hyperintensity of the neurohypophysis is not caracteristic of one type of lesion in particular but is correlated with the presence of a diabetes insipidus. The most important notion is to recognize that at the time of diabetes insipidus diagnosis in a child, the cerebral mass might be too small to be identified by MRI. In such patients, repeating imaging study

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4. 5.

Cemeroglu A., Blaivas M., Muraszko K., et al.: Lymphocytic hypophysitis presenting with diabetes insipidus in a 14-year-old girl: case report and review of the literature. Eur J Pediatr, 1997, 156: 684-688. Echevarrai M., Fangusaro J., Goldman S.: Pediatric Central Nervous System Germ Cell Tumors: A Review. Oncologist, 2008, 13: 690699. Cunliffe C., Fischer I., Karajannis M., et al.: Synchronous mixed germ cell tumor of the pineal gland and suprasellar region with a predominant angiomatous component: a diagonstic challenge. J Neurooncol, 2009, 93: 269-274. Osborn A., et al.: diagnostic imaging Brain, first edition Canada, Amirsys, 2007, I6: 132-139. Konovalov A., Pitskhelauri D.: Principles of Treatment of the Pineal Region Tumors. Surg Neurol, 2003, 59: 250-268.

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SPONTANEOUS CHOLECYSTOCUTANEOUS ABSCESS W.-J. Metsemakers1, I. Quanten1, F. Vanhoenacker2, T. Spiessens1 Spontaneous cholecystocutaneous abscesses or fistulae are rare complications of neglected biliary calculous disease which have become extremely rare during the last decades. We report a case of spontaneous cholecystocutaneous abscess in a 69-year-old male who presented with a mass in the right subcostal region. The diagnosis was made by CT scan with multiplanar reformating. Treatment consisted of incision and drainage of the abdominal wall abscess followed by cholecystectomy in a one-stage protocol. Key-words: Gallbladder, diseases – Abscess.

Spontaneous cholecystocutaneous abscesses or fistulae are uncommon complications of gallbladder disease. Thilesus first described the external biliary fistula in 1670 and it was Courvoisier who reported 169 cases in the nineteenth century. In their review in 1949, Henry and Orr found 36 cases of external biliary fistulas reported after 1890 (1). In the last decades these complications have become very rare, due to the improvements in diagnostic imaging, the use of broad-spectrum antibiotic therapy and advancements in biliary surgery (2, 3). We describe here a rare case of spontaneous cholecystocutaneous abscess. Case report A 69-year-old male was referred to the Emergency Department complaining of right upper quadrant abdominal pain that had lasted for 30 days. Clinical examination revealed a mass in the right subcostal region (Fig. 1). The patient had a history of cholecystolithiasis. Four months earlier he underwent an endoscopic retrograde cholangiopancreatography (ERCP) with papillotomy and temporary stent placement for obstructive choledocholithiasis. During a second ERCP, one month later, multiple gallstones were removed, together with the stent. On admission the patient was in a relatively good general condition, with a heart rate of 100 beats/min and a systolic blood pressure of 140 mmHg. He was afebrile and anicteric. The white blood cell count was 15.900/mm3 (4-8) with 77% segments and we noted a CRP of 10.1 mg/dl (< 0.5). Gamma-glutamyl-

Fig. 1. — Preoperative photograph of the patient revealed a mass in the right subcostal region.

transferase (GGT) was 124 U/L (< 61). The other laboratory data were unremarkable, including normal haemoglobin, bilirubin, alkaline phosphatase, amylase and glucose levels. Computed tomography (CT) showed a huge abscess in the right anterior abdominal wall in communication with the gallbladder (Fig. 2). The abscess was drained under general anaesthesia through a small skin incision, followed by a cholecystectomy and excision of the fistula tract through a midline laparotomy. Broad-spectrum antibiotics were administered preoperatively and continued for seven days postoperatively. Histopathological analysis revealed chronic cholecystitis with no evidence of malignancy. The postoperative course was uneventful.

From: Department of 1. Abdominal Surgery and 2. Radiology, General Hospital, AZ. St. Maarten, Duffel. Address for correspondence: Dr Willem-Jan Metsemakers, M.D., AZ St. Maarten, Campus Rooienberg, Rooienberg 25, B-2570 Duffel, Belgium. E-mail: willemjanmets@hotmail.com

Discussion Since the introduction of surgical treatment of gallbladder calculous diseases, the incidence of cholecystocutaneous abscesses and fistulae has reduced dramatically. The declining incidence is likely related to prompt diagnosis, availability of antibiotics, and early surgical intervention for cholecystitis and empyema (2, 3). Biliary fistulae can be divided into internal and external biliary fistulae by the site of exit of the fistulae. They are further subdivided based on etiology into spontaneously occurring or as posttraumatic, postoperative and iatrogenic fistulae. External biliary fistulae (biliocutaneous fistulae) or abscesses rarely occur spontaneously as a result of intrahepatic abscess, necrosis or perforation of the gallbladder, or other inflammatory process involving the biliary tree. They are more commonly postoperative or post-traumatic. Currently, iatrogenic fistulae complicating

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B Fig. 2. — Contrast enhanced computed tomography of the upper abdomen. A. Axial image. Note a multiloculated abscess extending through the right abdominal wall (black asterisks), communicating with the fundus of the gallbladder (white asterisk). B. Axial image at a slightly lower level shows a huge abscess at the abdominal wall. C. Coronal reformatted image demonstrates more accurately the craniocaudal extent of the lesion.

C biliary tract surgery are the most common cause of external biliary fistulae (4). Spontaneous cholecystocutaneous abscesses or fistulae are invariably a complication of neglected calculous disease, although isolated case reports have described spontaneous cholecystocutaneous fistulae due to carcinoma of the gallbladder and acalculous cholecystitis (4, 5). Women are affected more than men, reflecting the higher incidence of cholelithiasis and cholecystitis among women (2). Pathophysiologically, there is an increase in intraluminal pressure which leads to impairment of the blood flow and lymph supply to the gallbladder, thus causing mural necrosis and perforation. Perforation can occur as acute-free perforation causing peri-

tonitis, subacute perforation resulting in an abscess around the gallbladder, or chronic perforation with the formation of an internal or external biliary fistula (2, 6). On clinical examination the patient may be febrile and diaphoretic because of the infection but this is not necessarily the case. Prior to rupture, a raised erythematous area of affected skin may be observed. The surrounding skin is often cellulitic, frequently leading to an initial diagnosis of abscess as was the case in our patient. The majority of the fistulae are found in the right upper quadrant (48%) or at the site of the umbilicus (27%) (1, 5). Because of the multiplanar reconstruction capabilities of modern CT technology, CT scan has become the imaging method of choice for pre-

operative diagnosis. When a cutaneous fistula is present some authors recommend a fistulogram because this should allow visualisation of the fistula tract and its origin (6). Ultrasonography is also an option but due to local pain the patient is often difficult to examine. Moreover ultrasonography is less accurate in diagnosing the origin of the abscess or fistula and is in our opinion no longer a standard imaging procedure for this kind of pathology. Traditional treatment for a spontaneous cholecystocutaneous fistula or abscess has consisted of abdominal wall incision and drainage followed by “staged” cholecystectomy (5). But during the last decades a one-stage treatment protocol has become the preferred option. A laparoscopic approach appears to be a feasible option but the conversion rate is high (7, 8). Both the gallbladder and fistula need to be resected to achieve a cure. Generally the prognosis is good. However, as this condition commonly occurs in elderly patients who may have multiple medical comorbidities, surgical treatment must be tailored depending on the patient’s fitness for surgery. In conclusion, spontaneous cholecystocutaneous abscesses or fistulae are uncommon complications of gallbladder disease. In case of a high clinical suspicion prompt diagnosis

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by CT scan is mandatory. Currently a one-stage, surgical, treatment protocol is the preferred option. In general the prognosis is good, however high age and coexisting medical problems may complicate therapy. References 1.

Henry C.L., Ort T.G. Jr.: Spontaneous external biliary fistulas. Surgery, 1949, 26: 641-646. 2. Vasanth A., Siddiqui A., O’Donnell K.: Spontaneous cholecystocutaneous

JBR–BTR, 2010, 93 (4) fistula. South Med J, 2004, 97: 183185. 3. Andley M., Biswas R.S., Ashok S., Somshekar G., Gulati S.M.: Spontaneous cholecystocutaneous fistula secondary to calculous cholecystitis. Am J Gastroenterol, 1996, 91: 1656-1657. 4. Knol J.A., Eckhauser F.E.: Biliary fistulas. In: Shackelford’s surgery of the alimentary tract, volume 3. Edited by Zuidema G.D., Yeo C.J. Printed by W.B. Saunders company, Philadelphia, 2002, pp 273-279. 5. Birch B., Cox S.: Spontaneous external biliary fistula uncomplicated by

gallstones. Postgrad Med J, 1991, 67: 391-392. 6. Nicholson T., Born M., Garber E.: Spontaneous cholecystocutaneous fistula presenting in the gluteal region. J Clin Gastroenterol, 1999, 28: 276-277. 7. Kumar S.S.: Laparoscopic management of a cholecystocutaneous abscess. Am Surg, 1998, 64: 11921194. 8. Mathonnet M., Maisonnette F., Gainant A., Cubertafond P.: Spontaneous cholecystocutaneous fistula: natural history of biliary cholecystitis. Ann Chir, 2002, 127: 378-380.

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SMALL BOWEL OBSTRUCTION DUE TO AN INTERNAL HERNIATION THROUGH A DEFECT OF THE BROAD LIGAMENT P. Mailleux1, A. Ramboux2 We report on a case of internal hernia through a defect of the broad ligament of the uterus. Early diagnostic may be possible with multidetector CT and lead to early treatment. MDCT can help achieving early preoperative diagnostic and allows early laparoscopic treatment with prompt recovery. Key-word: Intestines, stenosis or obstruction.

A hernia through a defect of the broad ligament is a very rare cause of internal hernia and its preoperative diagnostic was not frequent before the multidectector CT, with often late diagnostic and treatment. Improvements in CT scanner technology now allow in many cases the depiction of the uterine tube and the ovary, which are the upper border of the broad ligament, and this may lead to a preoperative diagnosis of broad ligament herniation (BLH) and an early laparoscopic successful treatment. We report such a case.

Case report A 38-year-old lady, with no medical or surgical history, who had had two pregnancies with vaginal delivery was admitted for very acute mid and lower abdominal pain during the past 3 hours. There was no vomiting and clinical examination was normal, with no abdominal distension and a normal basic biology workup. A CT scan (64 slices multidector HD750 General Electric, 120 Kv, 70 seconds after injection of iodinated intravenous contrast, without any oral or rectal opacification) was performed to exclude perforation and showed a few dilated bowel loops in the posterior pelvis, without any infiltration of the related mesentery but with some fluid around the distended loops (Fig. 1). On oblique “targeted“ reconstructions, it was possible in this case to follow the right Fallopian tube from the uterine fundus to the ovary (Fig. 2A) and to see that the mesenteric vessels related to the dilated loops were located just under that Fallopian tube, directed from anterior to posterior (Fig. 2B and fig. 3). Proposed preoperative

★ ★ C

Fig. 1. — A “Standard” axial CT slices after injection of intravenous contrast. No bowel distension in the upper abdomen. B Presence of a few dilated loops in upper pelvis. C and D: Fluid-filled dilated small bowel loops in the posterior pelvic cavity (star) and minimal fluid effusion around the distended loops (arrows).

diagnostic was an internal herniation through the broad ligament, inflammatory or tumoral causes being excluded. Laparoscopic surgery performed 4 hours after patient admission confirmed the herniation through a defect in the right broad ligament, the incarcerated bowel was viable and no resection had to be done. The patient left the hospital 21 hours after surgery and clinical follow-up was favorable.

From: 1. Department of Imaging, 2. Department of Surgery, Clinique St Luc, Bouge, Belgium. Address for correspondence: Dr P. Mailleux, M.D., Dpt Medical Imaging, Clinique St Luc, Rue St Luc 8, 5004 Bouge, Belgium.

Discussion Internal herniation is a rare cause of small bowel obstruction (1%), and broad ligament obstructions represent only 5% of internal herniations (1). Clinical presentation of internal herniations is often difficult and misleading, the occlusion being often a closed loop obstruction, with equivocal or non specific findings from emergency plain abdominal radiographic studies (2), with no abdominal distension, no vomiting. Diagnostic is often late, with vascular incarceration having caused necrosis of parts of the small bowel. In the cases of BLH, the herniated structure is nearly always the small

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➥ ➥ ★

★

Fig. 2. — A. “Targeted” slightly oblique slice through the uterine fundus (large arrow), uterine tube (small arrows) and ovary (curved arrow), structures that delimitate the upper border of the broad ligament. B. Just below this area (uterine fundus and ovary still visible), a bowel loop with its vessels and non infiltrated mesenteric fat around those vessels, directed from anterior to posterior (white arrow) is seen.

➥

Fig. 3. — Oblique coronal CT slice of the parauterine fossa. Superior border of the broad ligament is visible through its landmarks (uterine fundus: large arrow, uterine tube: curved arrow and ovary: small arrows). Dilated small bowel loop seen just below (star) going through a defect in the broad ligament.

bowel. Incriminated factors are surgery, endometriosis and treatment of endometriosis, pelvic inflammatory disease and congenital abnormality Pregnancy and delivery could be factors associated with broad ligaments defects (3), only 3 of the 57 cases reported in Japan by Terado (1) had no history of pregnancy, Hunt (4) classified the internal

Fig. 4. — Anatomic drawing (Gray’s Anatomy of the Human Body, published in 1918, the content of which is in the public domain: no copyright). Posterior view of the broad ligament that separates the lateral part of the pelvic cavity into an anterior and a posterior compartment, The upper border of this separation is the uterine tube connecting the uterine fundus to the ovary, and those structures that can often be depicted on multidetector CT.

herniation through the broad ligament into two types: the fenestra type that involves both the anterior and posterior leaves of the ligament and the pouch type in which the defect involves one layer only. Previous reports generally have described the fenestrated type, and the defect in the present case was of the fenestra type.

The herniation of the small bowel loop can have an anterior-posterior direction (as in our case), or a posterior-anterior direction (1). Uterus displacement to the contralateral side by the herniated loop can be seen. While in our case there was no irreversible damage to the incarcerated loop, many patients are found to have segmental ischemia and

INTESTINAL OBSTRUCTION DUE TO HERNIATION THROUGH A DEFECT OF THE BROAD LIGAMENT â&#x20AC;&#x201D; MAILLEUX et al

infarction necessitating segmental resection. In the CT description of previous reports (1, 3), the location of the herniated loops and their close proximity to the uterus were considered CT findings strongly suggesting BDH. In many cases, thin slices and possibility of reconstruction in any plane allowed by multidector CT can probably help the radiologist in assessing the location of the ovary and the Fallopian tube. The Fallopian tube constitutes the upper border of the broad ligament (Fig. 4). When this uterine tube is seen, and if the herniated loops cross below it, where the leaves of the broad ligament should be, the diagnosis of

BDH through a defect is easily made, followed by quick surgical treatment.

Bibliography 1.

Conclusion MDCT with its thin slices and its ability to perform oblique slices in any plane can help the radiologist in assessing the location of the Fallopian tube. This proved to be helpful in a case of small bowel obstruction due to internal herniation in a defect of the right broad ligament. The patient could be operated immediately laparoscopically, without any resection and with a rapid recovery.

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Haku T., Daidouji K., Kawamura H., Matsuzaki M.: Internal herniation through a defect of the broad ligament of the uterus. Abdom Imag, 2004, 29: 161-163. 2. Balthazar E.J., Liebeskind M.E., Macari M.: Instestinal ischemia in patients in whom small bowel obstruction is suspected: evaluation of accuracy, limitations and clinical implications of CT in diagnosis. Radiology, 1997, 205: 519-522. 3. Takaeyama N., et al.: CT of internal hernias. Radiographics, 2005, 25: 9971015. 4. Hunt A.B.: Fenestrae and pouches in the broad ligament as an actual and potential cause of strangulated intraabdominal hernia. Surg Gynecol Obstet, 1934, 58: 906-913.

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ACETABULAR OSTEOID OSTEOMA TREATED BY PERCUTANEOUS RADIOFREQUENCY ABLATION: DELAYED ARTICULAR CARTILAGE DAMAGE P.P. Bosschaert, F.C. Deprez1 The authors report the case of an osteoid osteoma of the acetabular roof in a 17-year-old sportsgirl successfully treated by radiofrequency ablation, with a mid-term evidence of cartilage loss. Extra-articular access and exact positioning of the needle electrode exclude direct operative chondral damage. Intense physical activity could be an aggravating factor for the chondropathy. It is difficult to determine whether the acetabular cartilage joint was damaged only by thermo-ablation or if it had also been weakened before by the O.O. The authors caution practitioners from using this technique for para-articular lesions, especially near weight-bearing joints. Key-word: Osteoid osteoma – Articular cartilage damage – Radiofrequency – Thermo-ablation.

Case report A 17-year-old girl was referred to our institution for left hip chronic pain, with nocturnal episodes, pain witch was partially alleviated by the use of salicilates. Clinical examination showed normal hip mobility, with pain during internal and external rotation movements. Slight left quadriceps femoris muscle hypotrophy was observed compared to the right side. Conventional radiographs revealed a subtle subchondral sclerosis of the acetabular roof. Bone scintigraphy indicated an increased radiotracer uptake on the left hip. Computed tomographic (CT) scan showed a small radiolucency with central calcification, named nidus, and surrounding reactive osteosclerosis, localized on the weight-bearing surface of the acetabulum (Fig. 1). Osteoid osteoma was diagnosed. After informed consent, radiofrequency ablation (RFA) was performed under general anaesthesia and real-time CT guidance, in a sterile environment. The 14G penetration cannula (Bonopty; Radi Medical Systems, Uppsala, Sweden) was orientated on the nidus by an anterolateral way. The central trochar was removed and the nidus was drilled. The RF-probe, a Soloist Single Needle Electrode (RadioTherapeutics, Boston Scientific, Boston, USA), was advanced into the nidus (Fig. 2), and connected to the RF generator, an RF3000 Radiofrequency Ablation System (RadioTherapeutics, Boston Scientific). In this case, the electrode tip was heated for 8 minutes. Initial

Fig. 1. — Axial (A) and coronal (B) CT imaging. Osteoid osteoma caracterized by a small lacunar lesion with central calcification (nidus) and surrounding reactive osteosclerosis (arrow).

power was 2 watts, with an increase of 1 watt per minute until 5 watts was reached, when impedance increased and the current delivered to the needle electrode decreased indicating desiccation (Roll-Off). We stopped and waited approximately 60 seconds. We restarted at 70% of the highest set power. Roll-off indication was for a second time obtained 3 minutes later. The lesion was considered to be treated at this point. The procedure was completed without any complications. The patient recovered quickly and was discharged in the evening. Total body weight-bearing was allowed. We recommended avoiding intensive phys-

From: 1. Department of Radiology, Clinique St-Pierre, Ottignies, Belgium. Address for correspondence: Dr P. Bosschaert, Department of Radiology, Clinique StPierre, Avenue Reine Fabiola 9, 1340 Ottignies, Belgium.

ical activities for 6 weeks. Antiinflammatory medications were administrated as required for the initial three days. Our patient didn’t present any complaints for the first six months. She was able to take up intensive dance practice (13 hours per week) without experiencing any pain. A follow-up magnetic resonance imaging (MRI) performed at the end of the six months didn’t reveal any abnormalities. There was a fat conversion on the location where osteosclerosis was seen on CT (Fig. 3) (1). One year after treatment, the patient complained of occasional acute left hip pain related to intense physical exercise, which disappeared quickly with rest. MRI then revealed development of a subchondral cystic structure at the acetabular roof (Fig. 4). No intra-articular joint effusion was seen. A CT-arthrography of the joint demonstrated a focal 4 mm2 acetabular cartilage loss near

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tinued which resulted in the disappearance of hip pain. No specific treatment was further advised at this stage. Discussion

Fig. 2. — Sagittal CT imaging. Optimal RF-probe position in the osteoid osteoma by extra-articular antero-lateral way.

Fig. 3. — Coronal MRI imaging. (A) T2-weighted and (B) T1-weighted images reveal a fat conversion of bone marrow without oedema.

Fig. 4. — Coronal MRI imaging. (A) T2-weighted and (B)T1-weighted images reveal a 25 mm wide subchondral cyst (hypoT1- and hyperT2-weighted signal), near the osteoid osteoma.

the RFA site (Fig. 5). The femoral head cartilage was normal. We concluded that this focal chondropathy was a mid-term complication of the

osteoid osteoma thermo-coagulation, probably heightened and aggravated by intensive sports. Dance training was therefore discon-

Osteoid osteoma (O.O.) is a benign skeletal tumor of unknown origin with a low rate of growth and rarely exceeding a diameter of 1015 mm. It represents 12% of benign bone tumors, affects teenagers or young adults and causes nocturnal pain often relieved by salycilates. If located near a joint, other symptoms of O.O. include swelling and restricted movement. Resolution may be spontaneous but is unpredictable, and surgery or a less invasive procedure such as percutaneous RFA is usually required. Definitive treatment is achieved by complete destruction of the nidus. In 2003, Rosenthal et al. (2) reported that RFA was preferred to open surgery as the primary treatment for this type of bone tumor. RFA therefore became «the standard treatment for O.O. over the past decade» (3). Permanent success occurs in approximately 90% of patients after a single treatment. This procedure is provided on an outpatient basis and has a short recovery period. It can only be performed if the patient has the typical clinical and imaging findings. The location of the tumor must permit a safe access without risking damage to nerves, major blood vessels or the skin. If the nidus is more than 1 cm away from these structures, the procedure usually can be safely performed, but the treating physician must be vigilant because there is no hard direct data to support RFA in all situations. Few complications were reported with O.O. RFA. Among the more frequent of them are infections and skin burns, and also tendonitis or thrombosis and even some bone fractures. In addition, the needle passage may cause bleeding and nerve injury. If the tumor is in the proximity of the spinal cord or peripheral nerves with disrupted intervening cortical bone, then this procedure is not advised due to the lower thermal threshold of nerves. In their large-scale research, Rosenthal et al. mention many of these complications but does not mention any delayed complications such as articular damage. Technically, because of its small gauge, the Soloist Single Needle Electrode can be accurately placed and a small ablation zone targeted of approximately 1 cm in diameter,

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to determine whether the acetabular cartilage joint was damaged only by thermo-ablation or if it had also been weakened before by the O.O.. We therefore want to caution practitioners using RF treatment of para-articular lesions, especially for weightbearing joints. References 1.

Fig. 5. — CT imaging after joint opacification. Demonstration of a focal 4 mm² acetabular cartilage loss under RFA site (A: axial and B: coronal, arrow), associated with a subchondral cyst (C: coronal, arrowhead). 3.

with some variability of size and shape (usually slightly oval). Moreover, cortical bone is usually considered a good insulator against heat transmission. Vanderschueren et al. (4) described no significant relationship between intra- or extraarticular localization and unsuccessful treatment risk. Rosenthal et al. suspected that there was a risk of thermal injury for the articular cartilage but didn’t report any damage. Pinto et al. (5) also described thermal ablations of para-articular lesions without any complications. Martel and colleagues (6) specifically

studied the effects of RFA on joint surfaces. After they induced multiple RF lesions on the femoral heads of dogs, they concluded that cortical bone retained its integrity and articular cartilage was never damaged. The current case seems to be the first published case showing a midterm articular cartilage damage after RFA of an O.O. Extra-articular access and exact positioning of the drill and the RF needle electrode exclude direct operative chondral damage. In this case, regular intense dance practice could be an aggravating factor for the chondropathy. It is difficult

Vanderschueren G.M., Taminiau A.H., Obermann W.R., et al.: The healing pattern of osteoid osteomas on computed tomography and magnetic resonance imaging after thermocoagulation. Skeletal Radiol, 2007, 36: 813-821. Rosenthal D.I., Hornicek F.J., Torriani M., et al.: Osteoid osteoma: percutaneous treatment with Radiofrequency Energy. Radiology, 2003, 229: 171-175. Neeman Z., Wood B.J., et al.: Radiofrequency ablation beyond the liver. Techniques in Vascular and Interventional Radiology, 2002, 5: 156-163. Vanderschueren G.M., Taminiau A.H., Obermann W.R., et al.: Osteoid osteoma: factors for increased risk of unsuccessful thermal coagulation. Radiology, 2004, 233: 757-762. Pinto C.H., Taminiau A.H., Vanderschueren G.M., et al.: Technical consideration in CT-guided radiofrequency thermal ablation of ostoid osteoma: Tricks and trade. AJR, 2002, 179: 1633-1642. Martel J., Bueno A., Dominguez M., et al.: Percutaneous radiofrequency ablation: relationship between different probe types and procedure time on length and extent of osteonecrosis in dog long bones. Skeletal Radiol, 2008, 37:147-152.

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PIGMENTED VILLONODULAR SYNOVITIS OF THE MIDFOOT P. Sierens1, M. Shahabpour1, V. Gombault2, F. Machiels1, M. Kichouh, M. De Maeseneer1 A 60-year-old man presented with a longstanding slowly growing swelling at the dorsal aspect of the left midfoot. The lesion was imaged with CT, ultrasound, and MR. On CT bony erosions were evident. On MR the lesions appeared bifocal and one component was hypointense on T2 weighted images suggesting hemosiderin deposits. The other component was hyperintense on T2 which is more unusual for PVNS. Imaging findings, however, suggested PVNS which was pathologically confirmed. A unique finding in this case is the late age of presentation of the disorder. Also the bifocal nature of the lesion is relatively uncommon. Key-words: pigmented villonodular synovitis, cuneonavicular joint, ankle and foot.

PVNS of the joints is not an uncommon disorder. It typically occurs in younger patients. Imaging findings usually allow a correct diagnosis. Bony erosions may be present later on in the disease, and on MR low signal intensity on T2 weighted images may suggest the diagnosis. In this case report the disorder occurred in an older patient which is unusual. Also the lesion was bifocal in nature which is not common. In addition one component of the lesion showed high signal on T2 which could be a misleading feature. Case report A 60-year-old male presents with a large painless swelling at the level of the dorsal aspect of the left midfoot which gradually increased in volume over the last few years. Recent complaints of increasing pain, localized tenderness and limitation of motion are evident. Further medical history was unremarkable. CT clearly shows sharply delineated osseous destructions at the level of navicular, cuboid and cuneiform bones (Fig. 1). Ultrasound examination demonstrates prominent hypervascularization of the lesions. MR examination is performed and demonstrates the presence of a superficial mass at the dorsal aspect of the articulation, between the navicular and the first and second cuneiform bones and a second component located at the plantar aspect of the cuneonavicular joints. Superficial and deep components of the mass both demonstrate promi-

Fig. 1. â&#x20AC;&#x201D; Axial plain CT images of the left foot show extensive bony erosions at the level of the navicular (A, straight arrow), cuboid, and cuneiform bones (B, curved arrow), but no lesions of the cuneonavicular articulation.

nent enhancement of the entire lesion after contrast administration on T1 (Fig. 2). Furthermore the lesion appears isointense to muscle on proton density (PD) and hypointense on T2-weighted spin echo (SE) and gradient echo (GE) images indicating the presence of hemosiderin deposits. The deep component is rather hyperintense on T2 GE however, most probably due to inflammatory reaction (Fig. 3). There are no signs of involvement of the extensor tendons and tendon sheaths. Overall, the bony destruction and signal patterns orient the diagnosis to PVNS rather than giant cell tumor of the tendon sheath.

From: 1. Department of Radiology, Universitair Ziekenhuis Brussel, Brussels, Belgium, 2. Department of Orthopaedics, Parc Leopold Hospital, Brussels, Belgium. Address for correspondence: Dr M. Shahabpour, M.D., Dpt of Radiology, UZ Brussel, Laerbeeklaan 101, B-1090 Brussels, Belgium. E-mail: maryam.shahabpour@uzbrussel.be

Surgery is performed and macroscopic observations confirms the characteristics of the lesion as being compatible with PVNS. The surgeon manages to resect the dorsal and plantar part of the lesion. Microscopically the specimen is made up of a collagen tissue matrix with the presence of abundant cuboid and fusiform cells of fibrohistiocytic nature, leucocytes and macrophages loaded with hemosiderin pigment, histiocytes charged with fat, multinucleate giant cells, as well as synovial lining cells (Fig. 4). Discussion PVNS clinically manifests itself as pain and joint swelling in young adults. Joint effusion is observed in the knee in some cases but is uncommon in other joints. Joint aspiration typically demonstrates a xanthochromic joint effusion (1). Imaging plays an important role in the diagnosis, treatment, and

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Fig. 2. â&#x20AC;&#x201D; A. Sagittal T1-weighted images show a soft tissue mass at the superficial aspect of the navicular and cuneiform bones (straight arrow) with cuboidonavicular transarticular extension with bone erosions (curved arrow) and prominent heterogeneous enhancement after contrast administration (B).

Fig. 3. â&#x20AC;&#x201D; A. PD and (B) T2 SE as well as (C) T2 GE coronal images demonstrate intermediate and hypointense signal intensity respectively for proton density and T2-weighted images, whereas T2 GE sequence shows hypointense signal intensity for the superficial aspect of the lesion (straight arrow) with small areas of very low signal intensity indicating the presence of hemosiderin. A heterogeneously increased signal intensity at the deep aspect of the soft tissue mass could suggest the presence of synovitis (curved arrow).

follow-up of the disorder. Conventional radiographs of joints affected by PVNS may appear normal or may demonstrate periarticular soft-tissue swelling. Joint spaces and bone mineralization are characteristically preserved until late in the disease. Bony erosions are common in joints with a tight capsule, such as the hip and ankle. On MR images, the mass-like proliferative synovium has a lobulated margin, and it may be extensive in diffuse PVNS or lim-

ited to a single nodule in the focal form. The lesions tend to bleed, causing hemosiderin deposition and a characteristic low signal intensity with all pulse sequences. Areas of high signal intensity on T2- weighted images may be present and are likely caused by inflamed synovium or joint effusions (2-6). This is a somewhat misleading finding that was present in our case, because more typically the signal intensity on T2 is low. PVNS should be considered in

ankle masses with bony erosions and low signal intensity masses on T1 and T2 MR imaging. PVNS is a benign proliferative disorder of the synovium that may affect the joints, bursae, or tendon sheaths. PVNS most often occurs in young to middle aged adults. A unique finding in this report was that the disorder occurred in an elderly patient. Two primary forms are described, including a diffuse form that affects the entire synovial lining

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tation of the lesion. PVNS should be suspected with any periarticular or intraarticular mass with low signal intensity on all MR imaging sequences. References

Fig. 4. — Hematoxylin-eosin staining (10 x) shows the hyperplastic synovium consisting of fibrous stroma containing foamy macrophages, lymphocytes, and plasma cells. On the left, two multinucleate giant cells are seen of which one is indicated (black arrow) and deposits of golden brown hemosiderin lie within the stroma itself as well as within the cytoplasm of synovial cell lining and macrophages (white arrow).

of a joint, bursa, or tendon sheath, and a focal or localized form also called localized nodular synovitis (7). The knee is the most frequently involved joint, followed by the hip, ankle, and shoulder. Local recurrence following surgical or arthroscopic synovectomy occurs in almost 50% of cases. Polyarticular involvement is extremely rare. Another unique finding in this case was the bifocal presentation of the lesion. PVNS is currently classified in the group of fibrohistiocytic tumors according to the WHO classification.The differential diagnosis for intraarticular masses is limited. Anatomic knowledge helps the radiologist in localizing masses to the joint space. Familiarity with the typical imaging characteristics allows one to make confident diagnoses of many of the diseases causing intraarticular masses, the most important ones being noninfectious

synovial proliferative processes such as lipoma arborescens and synovial osteochondromatosis, infectious and inflammatory diseases such as tuberculous arthritis and rheumatoid arthritis, deposition diseases such as gout and amyloid arthropathy, vascular malformations such as synovial hemangioma and arteriovenous malformations, malignancies with synovial osteochondromatosis and metastasis (8-11). At pathologic analysis, PVNS is characterized by synovial inflammation with multinucleate giant cell proliferation, collagen, and lipidladen macrophages. Treatment of PVNS often consists of resection of the lesion. However, a recurrence rate of 10%-20% is reported in the focal forms and of up to 50% in the diffuse forms (3, 12). In conclusion we report a case of PVNS of the midfoot. Unique findings in our case were the older age of the patient and the bifocal presen-

1. Llauger J., Palmer J.: MR Imaging of benign soft-issue masses of the foot and ankle. Radiographics, 1998, 18: 1481-1498. 2. Dorwart R.H., Genant H.K.: Pigmented villonodular synovitis of synovial joints: clinical, pathologic, and radiologic features. AJR, 1984, 143: 877-885. 3. Jelinek J.S., Kransdorf M.J.: Imaging of pigmented villonodular synovitis with emphasis on MR Imaging. AJR, 1989, 152: 337-342. 4. Kransdorf M.J., Jelinek J.S.: Softtissue masses: diagnosis using MR Imaging. AJR, 1989, 153: 541-547. 5. Cheng X.G., You Y.H., Liu W., Zhao T., Qu H.: MRI features of pigmented villonodular synovitis. Clin Rheumatol, 2004, 23: 31-34. 6. Murphey M.D., Rhee J.H., Lewis R.B., Fanburg-Smith J.C., Flemming D.J., Walker E.A.: Pigmented villonodular synovitis: radiologic-pathologic correlation. Radiographics, 2008, 28: 1493-1518. 7. Ganse B., Behrens P., Gellissen J., Krüger S., Benthien J.P.: Localized nodular pigmented villonodular synovitis of the upper ankle joint - diagnosis and treatment. Z Rheumatol, 2006, 65: 231-234. 8. Sheldon P.J., Forrester D.M., Learch T.J.: Imaging of intraarticular masses. Radiographics, 2005, 25: 105119. 9. Waldt S., Rechl H., Rummeny E.J., Woertler K.: Imaging of benign and malignant soft tissue masses of the foot. Eur Radiol, 2003, 13: 1125-1136. 10. Laffan E.E., Ngan B.Y., Navarro O.M.: Pediatric soft-tissue tumors and pseudotumors: MR imaging features with pathologic correlation. Radiographics, 2009, 10.1148/rg.e36. 11. Wu J.S., Hochman M.J.: Soft-tissue tumors and tumorlike lesions: A systematic imaging approach. Radiology, 2009, 253 (2): 297-316. 12. Lin J., Jacobson J.A., Jamadar D.A., Ellis J.H.: Pigmented villonodular synovitis and related lesions: The spectrum of imaging findings. AJR, 1999, 172: 191-197.

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SPECIAL ARTICLE X-RAY CONTROL OF BORDERS AND OF INTERNAL SECURITY H. Vogel1 Objective: Security control with X-rays means exposure to ionising radiation and creates the possibility of access to personal privacy. Internal security concerns the police and secret services. The used technologies and their possibilities are described. Material and method: Observations and additional information have been collected. The exposure dose has been measured. Results: Several technical set ups are in use: Transmission imaging (fluoroscopy), backscatter imaging, computed tomography and several combinations. The search of persons concerns the interior of the human body, its surface and the clothing together with the luggage. One looks for weapons, explosives and drugs. The exposure dose is low compared to the exposure dose by a flight or due to a holiday in a country with higher environmental radiation by external sources like Finland. Conclusion: In the future, the security control will increase. Using X-rays creates the possibility to inspect privacy. Key-words: Forensic radiology – Radiology at Large.

have been analysed and evaluated. Personal collections of the operators and images provided from the manufactures have been reviewed. This became possible on the occasion of radioprotection project; for the German government the exposure dose in non medical X-ray exposures of humans was measured (1, 2). Examples will be displayed to demonstrate that this technology can contribute to security controls (3). Methods of clinical radiology like simple radiographs and computed tomography are employed, furthermore, two methods adapted for control purposes: transmission imaging (fluoroscopy) (Fig. 1) and backscatter imaging (Fig. 2) (4, 5).

The control of a person concerns the interior of the human body, its surface with the clothing, and the luggage. One looks for weapons, explosives and drugs. At the airports in some countries, the control of the passengers includes transmission imaging (fluoroscopy) combined with backscatter imaging, furthermore, computed tomography for

From: 1. Dpt. of Forensic Radiology, Institut Institute for Legal Medicine of the University Hospital Eppendorf, Hamburg, Germany. Address for correspondence: Prof. Dr. Hermann Vogel, Forensic Radiology, Institut de la Medicine Légale de Hôpital Universitaire Eppendorf, Butenfeld 34, D-22529 Hamburg, Germany.

Fig. 1. — Transmission imaging (fluoroscopy). The image results of a scan: The person slides back and forth (1) for some seconds. A pencil beam (2) scans the person. This beam is adjusted to a line of detectors. The digitised image appears on a screen (3)*.

Background A tourist travels for pleasure, a manager for money, a terrorist for attack. Travellers and carriers transport admitted and prohibited goods. Travel and transport can be the target of terrorist attacks; both can be part of the preparation of terrorist act. Travel and transport belong to our life and to our culture; they are part of the globalisation. Migration is another phenomenon of globalisation; it is together with terrorist attacks perceived as a threat and induces the urge of protection. Politics reacts and enforces border controls. There are multiple technologies which are employed which use X-rays for search for men, search of men and luggage; they aim to discover weapons, explosives, drugs and contraband. The exposure to Xrays means radiation risk, imaging with X-rays means opening up privacy to inspection. Airports are examples, where these applications are employed. It is intended to describe which technologies are in use, today. Internal security concerns the police and the secrete services.

These two methods are also employed to control vehicles of different size; this includes containers, and covers also railway wagons, tank trucks and helicopters. X-ray control of borders Search of persons

Material and method Observations and descriptions have been collected. The principles and the technologic realisations

X-RAY CONTROL OF BORDERS AND OF INTERNATIONAL SECURITY — VOGEL

accompanied and unaccompanied luggage. The manufacturers offer their equipment for controlling the access to commercial centres, national monuments (in the US: the Capitol and the Statue of Liberty), and the schools at risk of excesses of

violence. The fear that a nuclear explosive device could enter the US hidden in a container has provoked the control of containers and of shipped palettes (5). One consequence has been that by the control privacy is open to

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inspection by the controller (Fig. 3) and that societies have reacted thereupon. However, the reason for control with X-rays remains the necessity to discover weapons, drugs and contraband (Fig. 4). There are set ups which show persons practically naked; the image of a person can be displayed with a quality of a photo; this is especially valid for backscatter imaging equipment (Fig. 5). However, embarrassing details may also be visualised with transmission imaging (Fig. 6). Technical solutions exist which separate the display of weapons, explosives, drugs, and contraband from the visualisation of the person. Special software suppresses the person’s traits and displays the recognised object. Furthermore, software has been developed which modifies the image of the human body and prevents the recognition of the controlled person (Fig. 5 and 7). Luggage control X-rays penetrate hand luggage, parcels and containers; they become transparent, dangerous objects

Fig. 2. — Backscatter imaging: The X-rays, which are scattered backwards are registered; they are employed to produce an image of the body’s surface**.

Fig. 3. — Backscatter images for demonstration: on the left a model with a pistol hidden under her clothing. On the right, a vice president with a pistol under her clothing – she was disappointed when she saw her image on the screen**.

Fig. 4. — Weapons, explosives, and drugs visualised with X-rays. Backscatter image**.

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Fig. 5. — Pistol under the clothing. The displayed image shows the male-model practically naked. Backscatter imaging**.

Fig. 6. — Pusher, drug parcel in the vagina. Sexy underwear and intim piercing (arrow). The drug courier intends deviating the controller’s attention***.

Fig. 7. — Alienation of the person’s image combined with the recognition of a known object (pistol). Transmission imaging*.

Fig. 8. — Combination of radio spectroscopy with localisation by another imaging method. The imaging shows and localises parcels in bottles. The registered spectrum is compared to those of a library for identification of the substance under suspicion.

become visible. The controller looks for weapons; he looks for an ignition device to identify explosives and bombs. The radiography shows details which may lead to the culprit. X-ray imaging allows inspecting the contents of suitcases, boxes, and containers without being noticed; without touching a person a firearm

is recognised by its form, size and the density of its parts. Explosives and drugs are identified with double energy imaging and radio spectroscopy (Fig. 8) (6). Employed methods are transmission imaging (fluoroscopy), backscatter imaging, double energy imaging, and computed tomogra-

phy. Combination of different imaging methods exist (Fig. 9**) (4, 6). Control of vehicles, containers and shipped goods There are different technologies which are employed: Transmission images are obtained by using high

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Fig. 9. — Same suitcase controlled with three different methods. The transmission image shows many details; however, superimposition limits the recognition of the essential.

Fig. 10. — Truck control; combination of transmission imaging with backscatter imaging. Drugs (circle)**.

Fig. 11. — Person hidden in the trunk of a car. Backscatter imaging**.

energy ionising radiation produced with accelerators or liberated by radioactive substances like Cobalt60 or Cesium-137; transmission imaging can be combined with backscatter imaging (Fig. 10) (5,7). Illegal immigrants Search for persons concerns autos (Fig. 11), trucks, containers and railway wagons (Fig. 12). Even helicopter control with backscatter imaging is possible (5, 8). Secret services In the former German Democratic Republic (GDR) the Ministry for State Security (Ministerium für Staatssicherheit, MfS, Stasi) was in charge of the internal security. At the border between the two German states, 17 out of 27 stations disposed of equipment for vehicle control with transmission imaging. Cesium-137 was used.

Fig. 12. — Economic refugees hidden in a railway coal wagon. Empty drive. Transmission imaging**.

For pursuing suspected persons the Stasi employed different methods with application of a variety of radioactive substances applied in form of sprays, foils, and radiating needles. 50 to 70 operations were performed each year in the seventies and eighties of the former century. The marking of vehicles with Silver110m may serve as example: A special projectile had been developed for an air gun; it contained a wire of Silver-110m; this projectile was placed into the tire of a vehicle with a shot; the design covered distances up to 25m. After the fall of the wall in 1989, the Stasi destroyed the documents and the equipment; in consequence, our knowledge of the dimension of the use of radioactive material rests fragmentary. All the more, the Stasi, employed irradiating substances for marking passports, individuals, shoes, and clothing. The Stasi contaminated the floor to identify the

participants of a meeting, and the pages of a manuscript of a dissident writer to identify the persons who transported it into the west. The Stasi had designed a special detection device for ionising radiation, which would be concealed under the clothing of the pursuing agent and which would indicate the radiation by vibration; a pursuit without intervisibility was possible (5, 9-11). Discussion Today, travellers are controlled with X-rays in Europe (Heathrow, and in 1998 at Charles de Gaulle), in Australia, and in North America at several airports. These controls mean exposure to X-rays and they have not to be confounded with controls employing millimetre waves being installed recently at Schiphol airport. The control with ionising radiation allows visualising details, which are considered

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personal and, therefore, part of a person’s privacy needing protection. A person’s figure can be displayed practically naked on the control screen (3). Furthermore, radiographs displaying illegal immigrants hidden in trucks behind goods or in containers raise the question of human dignity. Public discussion and these observations pose the question of radiation exposure; frequently, this question indicates a feeling of discomfort more difficult to express. Our group has measured the exposure dose; it is lower than the additional dose received during a flight or during holidays in a country with a higher exposure dose due to radiation from natural sources like Finland (Table I) (1, 2). The manufacturers have reacted; they have replaced the person’s image by its silhouette (Fig. 5); furthermore, they have created the software able to identify suspicious objects. It seems realistic to expect that the visual control can be avoided in the future. Scanning with X-rays offers the possibility to obtain biometric data, which can be compared to those contained in a library, in personal documents (passport), or in implanted chips. A plausibility check seems realistic; a cross dresser could be recognised. Height, sex, age could be deduced from a radiograph. A combination of the person’s control with that of its luggage is imaginable. Up till now, this has not been realised. It seems probable that such a possibility will be part of a discussion, if the analysis of a

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(future) terrorist attack leads to the conclusion that the attack could have been prevented by using such designs. The control of persons and of goods has been initiated by terrorist attacks. Lockerbie, Richard Reid, and the World Trade Centre are landmarks. The attempt of Richard Reid, who tried to ignite explosive hidden in his shoes, induced shoe control; every passenger has to get out of his shoes to let them been X-rayed before being allowed boarding his flight to the US. The attack on the World Trade Centre induced luggage control with computed tomography. Today, politicians have reacted to the “Transatlantic Aircraft Plot” and prohibited carrying liquids in the hand luggage; in England, plans had been detected to compose liquid explosive out of different chemicals, which should be brought the airplane separated from each other (5). It may be allowed predicting that future control will combine different methods. One may conclude that security technology has initiated a development, which is influenced and which influences politics and how society perceives a threat. It is apparent that the potential of radiology surpasses that realised in medicine. It is probable that terrorist attacks with many victims would provoke the demand for this security technology. The border between privacy needing protection and the wish to be protected from terrorist attack will change in the future.

Table I. - Exposure dose, Hp(10), during flight, controls, and holidays (modified after 1 and 2) Hp(10) in µSv Backscatter imaging

0,1

Transmission imaging

Frankfurt - New York 7 hours

Germany, external exposure natural sources

2100 µSv/year

40 µSv/week

Finland, external exposure natural sources

8000 µSv/year

150 µSv/week

Chest X-Ray

10-100

8000-15000

Conclusion War against terrorism has created new conflicts. The individual feels threatened; airports and airplanes are sites where the threats may realise. In security control, several systems and technologies compete among each other. In the future, the number of security controls will increase. Time and costs will become a major issue. Automation will become an obligation. The control with X-rays has the inherent possibility to visualise a person’s privacy, to show the person naked, and to inspect the interior of the human body. Even identification and authentification can be realised. * Courtesy Compass Security, with permission ** Courtesy AS&E, with permission *** Courtesy Algra PR – Medical Center Alkmaar, The Netherlands, with permission References 1. Hupe O., Ankerhold U. Determination of ambient and personal dose equivalent for personel and cargo security screening. Radiat Prot Dosim,2006, 121: 429-437. 2. Hupe O., Ankerhold U. X-ray security scanners of personnel and vehicle control: Dose quantities and dose values. Eur J Rad, 2007, 63: 237-241. 3. Haller D.O. Röntgenkontrollen an Grenzen. Diss. University of Hamburg, Faculty of Med. 2007. 4. Vogel H. Search by X-Rays applied technology. Eur J Rad, 2007, 63: 227236. 5. Vogel H. Violence, war, borders. Xrays: Evidence and threat. ShakerVerlag, 2008, Aachen, ISBN 978-38322-7024. 6. Vogel H. Luggage and shipped goods. Eur J Rad, 2007, 63: 242-251. 7. Vogel H. Vehicles, containers, railway wagons. Eur J Rad, 2007, 63:254-262. 8. Vogel H. Search for persons. Eur J Rad, 2007, 63: 220-226. 9. Vogel H. Ionizing radiation in secret services’conspirative actions. Eur J Rad, 2007, 63: 263-269. 10. Eisenfeld B., Auerbach Th., Weber G., Plugbeil S. Bericht zum Projekt: „Einsatz von Röntgenstrahlen und radioaktiven Stoffen durch das MfS gegen Oppositionelle – Fiktion oder Realität?“ Der Bundesbeautrage für die Unterlagen des Staatssicherheitsdienstes der ehemaligen DDR. Abteilung Bildung und Forschung (BF) 1-46, 2000. 11. Halter H. Es gibt kein Entrinnen – über radioaktive Grenzkontrollen der DDR. Der Spiegel, 1994, 51: 176-180.

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REVIEW ARTICLE VASCULAR LIVER ANATOMY AND MAIN VARIANTS: WHAT THE RADIOLOGIST MUST KNOW M. Seco1, P. Donato1, J. Costa1, A. Bernardes2, F. Caseiro-Alves1 Advances in surgical techniques are extremely demanding regarding the accuracy and level of detail expected for display of the vascular anatomy of the liver. Precise knowledge of the arterial, portal and hepatic vein territories are mandatory whenever a liver intervention is planned. Sectional anatomy can now be routinely performed on multidetector computed tomography (MDCT) with volumetric data and isotropic voxel display, by means of sub-millimetric slice thickness acquisition. The relevant vascular information can thus be gathered, reviewed and post-processed with unprecedented clarity, obviating the need for digital subtraction angiography. The scope of the present paper is to review the normal vascular liver anatomy, its most relevant variants including additional sources of vascular inflow. Apart from providing the surgeon with a detailed vascular and parenchymal roadmap knowledge of imaging findings may avoid potential confusion with pathologic processes. Key-word: Liver, anatomy.

Despite refinements in liver surgical techniques, particularly microvascular reconstructions, vascular complications still account for considerable morbidity and mortality. Presurgical planning of vascular anastomosis and variations is a key component for a variety of liver surgeries, including transplantation, tumor resection, and laparoscopic hepatobiliary surgery (1). Detailed knowledge of the hepatic angioarchitecture is thus considered a prerequisite for successful, uncomplicated liver surgeries (1-3). The goals are to choose the best therapeutic approach, to reduce complications, and to identify the anatomy requiring special attention at surgery. From the various sectional imaging techniques undoubtedly multidetector computed tomography (MDCT) providing high spatial and temporal resolution is at the forefront of the evaluation of vascular liver anatomy (4, 5). Therefore, the aim of this paper is to review and illustrate the normal anatomy and main variants of the hepatic vasculature using MDCT with advanced post-processing algorithms, as well as to review current concepts of liver segmentation (VR) (6, 7). Arterial anatomy The anatomy of the hepatic artery and its variants has been widely described in the literature especially

Table I. Michels’ classification of hepatic arterial anomalies Type

Description

Prevalence (%)

I II III IV V VI VII VIII a) VIII b) IX X

Normal anatomy Repl. LHA from LGA Repl. RHA from SMA Repl. LHA from LGA and repl. RHA from SMA Acc. LHA from LGA Acc. RHA from SMA Acc. LHA from LGA and acc. RHA from SMA Acc. LHA from LGA and repl. RHA from SMA Repl. LHA from LGA and acc. RHA from SMA CHA from SMA CHA from LGA

55 10 11 1 8 7 1 2 2 4.5 0.5

LHA left hepatic artery, LGA left gastric artery, RHA right hepatic artery, SMA superior mesenteric artery, CHA common hepatic artery, Repl. replaced, Acc. Accessory.

provided by large autopsy series (813). Variants are seen as developmental changes of the primitive ventral splanchnic arteries. All the classical variations can consequently be explained by the abnormal disappearance of an arterial segment that should normally persist, persistence of an arterial segment that should disappear, or both. An aberrant hepatic artery refers to a branch that does not arise from its usual origin. The liver may receive blood supply directly from the superior mesenteric artery (SMA), left

From: 1. Department of Radiology, 2. Department of Surgery, Coimbra University Hospital, Coimbra, Portugal. Address for correspondence: Dr M. Seco, MD, Rua Maria Victória Bobone, Lote 22.3, apt. 331, P-3030-481 Coimbra, Portugal.

gastric artery (LGA), aorta, or other visceral branches corresponding to a complete transposition. However, these vessels may be accessory, meaning that they add on to the normal arterial supply which still represents the primary arterial supply to the liver. In Michels’ classic autopsy series of 200 dissections, published in 1955 (10), the basic anatomical variations in hepatic arterial supply were defined and this classification has served as the benchmark for all subsequent contributions in this area (4, 14-17). Michels described 10 types of configuration for the hepatic vasculature, including the normal configuration (Table I). Type I anatomy, consists of the common hepatic artery arising from the celiac trunk, from

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Fig. 1. — Normal hepatic arteries. Coronal thick slab MIP image (A) and cadaveric dissection (B). The common hepatic artery (CHA) arises from the celiac trunk (CT). After giving rise to the gastroduodenal artery (GD), it continues as the proper hepatic artery (PHA), which divides into right hepatic artery (RHA) and left hepatic artery (LHA).

B T n

Fig. 2. — Michels’ type III anatomy. A: VR image. The right hepatic artery (arrow) arises from the superior mesenteric artery (arrowhead). B: VR image. C: Axial CT. When the right hepatic artery arises (arrow) from superior mesenteric artery it runs upwards behind the pancreas and dorsal to the portal vein in the portocaval space. On C an invasive gallbladder tumour (T) and a mestastatic node (n) are seen.

Fig. 3. — Michels’ type IV anatomy. A: Thick slab coronal MIP image. B: VR image. The right hepatic artery (arrow) arises from the superior mesenteric artery and the left hepatic artery (arrowhead) arises from left gastric artery.

which the gastroduodenal artery and the proper hepatic artery arise (Fig. 1). The proper hepatic artery branches off the right hepatic artery (RHA) after the left hepatic artery (LHA). Further on RHA splits into its anterior and posterior branches and

the LHA splits to feed segments II and III. Segment IV is fed by one or more branches originating from the LHA, RHA, or both. The frequency of occurrence of normal hepatic arterial anatomy ranges between 55-76% (4, 18-19). In the type II Michels’ variant

the LHA originates from the left gastric artery (LGA). The replaced artery can be seen running through the lesser sac entering the liver via the fissure for the ligamentum venosum, into the umbilical fissure. This is the second most common arterial variant, occurring with a frequency of 10%. In the type III Michels’ variant the RHA branches off from the SMA (Fig. 2). Whereas the right hepatic artery usually courses anterior to the right portal vein, the replaced right hepatic artery, runs posterior to the main portal vein in the portocaval space, and classically ascends posterolateral to the common bile duct. This is the most common variant accounting for 11% of cases. Type IV Michels’ variant corresponds to a situation where type II and type variants III coexist: both lobar arteries are replaced with the RHA originating from the SMA and the LHA from the LGA (Fig. 3). This kind of variant is rare with a reported incidence of only 1%. The remaining types of this classification are described in table 1. For illustrative purposes two different cases of type VIII (Fig. 4) and IX (Fig. 5) are shown attending to their rarity accounting for 2 and 0.2% of all arterial variants, respectively. It should be stressed that other variants, not included in the original Michels’s classification have also been described such as a replaced RHA or the common hepatic artery originating directly from the aorta. Of special interest is the anatomy of the artery (or arteries) that feed segment IV, because of its importance for surgical procedures involving this specific segment such as the case of left liver donors for liver transplant in pediatric patients. Its configuration is quite variable and it is possible to observe a single, double, and triple supply, originating from RHA, LHA and/or proper hepatic artery (Fig. 6) . Usually the segment IV artery originates from the LHA in 64-75% of patients and from the RHA in 25% corresponding to what has been coined as the vascular arcade (5, 18, 20). Portal venous anatomy The portal vein is formed in the retroperitoneum by the confluence of the superior mesenteric vein and the splenic vein, behind the neck of the pancreas and courses behind the duodenal bulb. In its most common branching pattern it divides at the porta hepatis into right and left portal veins (Fig. 7). The portal bifurca-

VASCULAR LIVER ANATOMY AND MAIN VARIANTS — SECO et al

Fig. 4. — Michels’ type VIII anatomy. A: Thick slab MIP. The replaced right hepatic artery (arrow) arises from the superior mesenteric artery and there is an acessory left hepatic artery (arrowhead) that arises from the left gastric artery. B: Whenever the left hepatic artery arises from the left gastric artery it runs in the lesser omentum and enters the liver via venous fissure.

Fig. 5. — Michels’ type IX anatomy. A: MIP image. B: VR image. The main hepatic artery (arrow) originates from the superior mesenteric artery (arrowhead).

Fig. 6. — Segment IV artery. A: VR image. The middle hepatic artery (arrow) originates from proper hepatic artery. B: MIP image. In this case there is a double supply for segment IV (arrows), one branch originating from the left hepatic artery and the other branch from the right hepatic artery.

tion may be extrahepatic (48% of cases), intrahepatic (26%), or located right at the entrance of the liver (26%) (21, 22). As it courses cranially, the right portal vein first gives off collateral branches to the caudate lobe and then divides into anterior and poste-

rior branches, which further subdivide into superior and inferior segmental branches to supply the right lobe of the liver. The left portal vein first has a horizontal course (pars horizontalis) to the left and then turns medially toward the ligamentum teres (pars umbilicalis, ie, the

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vertical part), supplying the lateral segments (segments II and III) of the left lobe. It displays a wide anterior concavity ending up at the superior and inferior segmental branches of segment IV. The segmental veins divide into subsegmental branches, and further on into small veins abutting at the portal triad at the level of the liver acinus. Branching anomalies of the main portal vein (PV) at the hepatic hilum are known to be less frequent (1020% of cases) than those of the hepatic arteries and hepatic veins (23-26). Embryologically, the PV is formed during the second month of gestation by selective involution of vitelline veins, which have multiple bridging anastomoses, both anterior and posterior to the duodenum. Modifications in the pattern of these anastomoses end up in PV variations. According to the literature (25-27), the most common patterns are represented by: a) trifurcation of the main portal vein (7.8%-10.8%); in these cases, the main portal vein divides into three branches after entering the porta hepatis; a right anterior segment, a right posterior segment, and a left portal vein (Fig. 8); b) origin of the right posterior segmental branch directly from the main portal vein (4.7%-5.8%), where the main portal vein gives rise to the right posterior segment, then continues to the right for a short distance, and divides into the right anterior segmental branch and the left portal vein; c) origin of the right anterior segmental branch from the left portal vein (2.9%-4.3%); in these cases, the main portal vein divides into the right posterior segment and the left portal vein. The right anterior segmental vein originates from the left portal vein (Fig. 9). Less well defined variations of the “normal” distribution of portal vein are commonly seen. These include a short main right portal vein, a short horizontal portion of the left portal vein, disproportionate size of different segmental branches, and a small accessory branches (arising from the main portal vein) to the right posterior segment. Some of the latter variations correlate with differences in the size of some segments of the liver, where a hypoplastic segment receives small branches. There may be cases of congenital absence of the portal vein, where all the blood carried by the superior mesenteric and splenic veins bypasses the liver draining directly into a systemic vein. This congenital

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Fig. 7. — Normal portal vein anatomy. MIP image. The main portal vein (PV) divides into right portal vein (RPV) and left portal vein (LPV). The RPV bifurcates into anterior branch (AB) and posterior branch (PB), both of which bifurcate into ascending and descending branches. Each of these four branches supplies a segment of the right lobe. The left portal vein (LPV) divides into three branches, one for each segment of the left lobe.

Fig. 8. — Portal vein trifurcation. MIP image. Main portal vein (PV) divides into right anterior (AB) and posterior (PB) branches and left portal vein (LPV). A right portal vein is not identified.

Fig. 10. — Congenital absence of the portal vein. The splanchnic vein joins the inferior vena cava forming a porto-systemic congenital shunt (arrow). Note a large macroregenerative nodule (asterisk) secondary to the perfusion abnormality of the liver.

Fig. 9. — Right anterior segmental branch arising from the left portal vein. MIP image. There is an absence of the right branch of the portal vein. The portal vein (PV) bifurcates into a left and posterior branch (to segments VI and VII). The anterior branch (arrow) to segments V and VIII arises from the left branch of the portal vein (LPV).

malformation was first described by Abernathy in 1793 and is a clear example of a portosystemic shunt (Fig. 10). Morgan and Superina (28) subsequently refined the classification of portal shunting into two different types: type I, when all portal venous blood is shunted to a systemic vein,

with complete bypass of the liver (e.g. congenital absence of the portal vein). This type of shunt has been referred to as a ‘total’ shunt or ‘end/side’ shunt; type II shunt when only a portion of the portal venous flow is diverted from the liver corresponding to a ‘partial’ shunt or a ‘side/side’ shunt.

Hepatic veins anatomy The three main hepatic veins (right, middle, and left) drain into the inferior vena cava (IVC) approximately 1 cm below the diaphragm and 2 cm inferior to the lower border of the right atrium (Fig. 11). The right hepatic vein (RHV) is the one widest since it drains a larger volume of liver parenchyma (segments V-VIII). The middle hepatic vein (MHV) runs along the main portal fissure draining segments IV, V and VIII. The left hepatic vein (LHV) drains segments II and III and generally forms a common trunk with the middle hepatic vein (MHV) in 85% of cases, ulti-

VASCULAR LIVER ANATOMY AND MAIN VARIANTS — SECO et al

Fig. 11. — Normal hepatic veins. A: MIP image. B: VR image. Normal hepatic veins, usually consisting of three main hepatic veins: right hepatic vein (RHV), middle hepatic vein (MHV) and left hepatic vein (LHV). The LHV forms a common trunk (arrow) with the MHV in 85% of cases.

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small and numerous, but their clinical relevance for liver surgery, should only be acknowledged when its diameter exceeds 5 mm (Fig. 12). However, their pathophysiologic importance may be greater when the venous drainage of the liver is compromised, such as in Budd-Chiari syndrome or in cases of large central tumors of the liver. An accessory RHV occurs in 52.5% of patients (Fig. 13), two accessory hepatic veins in 12%, and a dominant accessory vein draining the caudate lobe in 12%. The most frequent variations found in literature are (31): a) a dominant right accessory hepatic vein seen in 3-5% of patients, which is larger in caliber than the right hepatic vein (which may be atretic or even absent in such a case); b) absence of a common trunk formed by the middle and the left hepatic veins; c) The vein that drains the liver near the falciform ligament is a tributary of the middle hepatic vein instead of the left hepatic vein. Also of paramount importance is the recognition of the territories of liver drainage of the hepatic veins. This has major implications in the context of liver donor liver transplant (LDLT) procedures where segmental territories may be deprived of their venous drainage ending up in venous congestion and reducing the final graft volume (Fig. 14) (32).

Fig. 12. — Accessory hepatic vein (arrow). MIP image. They are significant for surgical purposes when their diameter is superior to 5mm.

mately draining into the anterior left lateral aspect of the IVC (29,30). The LHV is the smallest of these veins. Segment I has its own venous drainage directly into the inferior vena cava via a variable number of independent veins. The anatomy of the major hepatic veins is quite variable. Also smaller accessory veins (AHVs) may be recognized, draining into the retrohepatic portion of the inferior vena cava between the right adrenal vein and the confluence of the main hepatic veins. These veins lack a precise systematization except for the accessory vein of segment VI, the largest and well recognized of all. AHVs are

Fig. 13. — Large accessory right hepatic vein (arrow), draining segment VI.

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Fig. 14. — Advanced liver segmentation in the context of liver donor liver transplant. Portions of the right liver lobe are drained by the middle hepatic vein (arrows). This should be known beforehand since it may modify surgical planning (areas at risk for passive congestion if middle hepatic vein is transposed to the donor).

Fig. 15. — Schematic drawing of non-portal splanchnic perfusion to the liver parenchyma . 1 - aberrant gastric vein drainage to segments I and IV. 2 - cystic veins to segments IV and V. 3 parabiliary venous system to the posterior aspect of segment IV. GB, gallbladder; ST, stomach; d, duodenum. According to Caseiro-Alves F, Ferreira A, Mathieu D. Focal Liver Lesions, Berlin, 2005, Springer. Chapter 11:160

Non-portal venous supply to the liver In some instances, veins draining digestive organs do not flow into the portal vein trunk, but instead abut directly into the liver parenchyma. These anatomical variations have been consistently reported, and angiographically demonstrated. This is the case for a cystic vein draining directly from the gallbladder into segments IV-V, the parabiliary venous system draining the pancreatic head, duodenum and distal stomach into the posterior aspect of segment IV and the aberrant gastric venous drainage coming from the gastric antrum and pancreatic head draining directly into segments I and IV (Fig. 15) (33). On dynamic contrast-enhanced CT/MR the liver areas receiving this venous drainage may show early enhancement due to earlier venous return of less diluted contrast agent when compared with the portal blood flow coming from the intestine and spleen. Another consequence derives from the fact that the blood conveyed by these third inflow tracts to the liver do not carry the lipotrophic factors and hormones (especially insuline) normally present in the portal flow and coming from the intestinal circulation. This may lead to focal parenchymal abnormalities such as fatty sparing and focal fatty infiltration (Fig. 16). Apart from the vascular variants other third inflow tracts feeding areas of liver parenchyma via direct

Fig. 16. — Veins of Sappey. A: Axial MIP. B: Sagittal MIP. Veins of Sappey are small veins (arrows) that drain into hepatic parenchyma around falciform ligament and are part of epigastric-paraumbilical venous system. C: These veins are responsible for perfusion and steatosic disorders (arrow) around falciform ligament.

connection with the systemic venous system may arise. This is the case represented by the superior vena cava obstruction leading to a network of collateral circulation between the thorax and the abdomen by intermediate of intercostal veins, internal mammary, hemiazygos and paravertebral veins. These systemic veins can end deeply in the umbilical vein, in the left portal vein or enter the left liver lobe directly by the paraumbilical inferior veins of Sappey (Fig. 16) (34). This explains the dense parenchymal staining, that may be seen in the early phases of liver enhancement near the round ligament, the left portal vein or in more remote subcapsular areas, corresponding to the early arrival of a considerable amount of minimally diluted contrast agent to these areas of liver parenchyma (35).

The parenchymal staining may be so intense that mimics a true hypervascular neoplasm (Fig. 17). Functional liver territories Liver anatomy can be described using two different concepts: morphological anatomy and functional anatomy. The gross description of the external liver anatomy does not take in account vessels and biliary ducts branching, which are of obvious importance for hepatic surgery. As an example, the quadrate lobe although belonging to the anatomical right lobe of the liver, is functionally dependent of the left lobe. Description of functional liver anatomy was initiated by Cantlie in 1898 and was followed by works of Healey and Schroy (36), Goldsmith and Woodburne (37), and more

VASCULAR LIVER ANATOMY AND MAIN VARIANTS — SECO et al

Fig. 17. — Two different patients with superior vena cava syndrome. A: There is an area, localized at segment IV, of intense and early enhancement, mimicking a hypervascular focal lesion. B: This case shows subcapsular venous collateral vessels at the right liver lobe again leading to a hyperdense pseudo-tumoral focal lesion.

Fig. 18. — The liver can be divided into four sectors: left lateral, paramedial left, paramedial right and lateral right. The separation lines (arrows) between sectors are called portal fissures and contain the hepatic veins.

Fig. 19. — The problem of separation between segment II and III on CT. A: On the axial plane we trace a line that intersects both the middle portion of umbical segment of portal vein and the left hepatic vein. Posterior to that line is segment II and anterior is segment III. B: On the sagittal plane the distinction between segment II and III is straightforward. Posterior to the left hepatic vein is segment II and anterior is segment III.

recently by Couinaud (38), and Bismuth (39). Couinaud (1957) proposed a liver segmentation system based on portal and hepatic veins. It includes eight segments divided by the second order branches of portal vein

with the argument that functional segmentation using the veins is preferred over arteriobiliary segmentation since portal vein branches off first, with arteriobiliary following the vein distribution. Portal segmentation is also simpler to use because it

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is less prone to anatomical variations. Couinaud divided the liver into two functional parts: the left and right liver, separated by a main portal fissure containing the middle hepatic vein, known as Cantlie’s line. Surface markings of this line are inaccurate but grossly correspond to a plane joining the gallbladder fossa anteriorly to the left side of the inferior vena cava posteriorly. The left and right hemilivers are further subdivided by the left and right hepatic veins, lying in the left and right portal fissure, corresponding to the bed of the hepatic veins (Fig. 18). The right hemiliver is subdivided into two main sectors drawing a second line that vertically runs along the right portal vein bifurcation: a right lateral sector, lying posterolaterally and a right paramedian sector lying anteromedially. Each sector is formed by two segments: the right lateral sector by segments VI and VII and right paramedian sector by segments V and VIII. The left portal fissure lies in the middle of left anatomical lobe and corresponds to a plane passing from the confluence of the left hepatic vein with the inferior vena cava towards the most lateral left lobe tip, dividing it into a left paramedian and lateral sectors. The left paramedian sector consists of segments III and IV. The left lateral sector is comprised only of segment II, which is the posterior part of the left lobe (Fig. 19). Sectional imaging is not well suited to determine the exact boundary between segments II and III. Its division can be assumed from a line drawn from the middle portion of vertical part of the left portal vein that joins the left hepatic vein. Oblique reconstructions using MIP algorithms can provide additional help for its demonstration (Fig. 19). From a functional point of view, the caudate lobe (or segment I) is an autonomous segment since its vascularization is independent from the main portal division and main hepatic veins. Bismuth has brought together the Couinaud’s cadaveric system in situ (38) and the classification system of Goldsmith and Woodburn in vivo (37). He distinguished three planes (scissurae), hosting the hepatic veins and a transverse plane passing through the right and left portal branches. The three hepatic veins divided the liver into four sectors. each supplied by its own portal pedicle (containing an arterial, portal vein, and bile duct branches).

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Although the above outlined concepts may be correct in some patients, from a morphologic point of view they can be questionable (40, 41). Anatomists such as Platzer and Maurer (40) pointed out that the variability of segmental boundaries is too large to render any scheme viable. Fasel et al (42) confirmed that the vertical planes that intersect the trunks of the hepatic veins do not correspond to the presumed intersegmental boundaries. Radiologists, as well, have published observations questioning the radiologic methods currently used for delineation of the segmental anatomy of the liver. Nelson et al (43) and Soyer et al (44) concluded that indirect landmarks are not reliable for the correct delineation of portal venous segments and subsegments. In opposition to the traditional landmarks (using the planes of the three major hepatic veins and the portal trunks as segmental boundaries), radiologists can localize lesions attributing them to the nearest peripheral portal vein branches. Rieker et al. (45) showed differences in segmental locations in 16% of the lesions analysed. These different locations were due to the path of the portal trunks or of the peripheral portal branches crossing the planes of the major hepatic veins. With current radiologic procedures based on indirect landmarks it is therefore not possible to exactly determine segmental and subsegmental anatomy of the liver. Also, every concept of flat planes delineating portal venous territories is an oversimplification which is not in full agreement with anatomic reality. True segmental and subsegmental determination is possible only with methods that account for the actual anatomy of the portal venous tree, incorporating off-branching of third and fourth-order portal branches. This can be more readily appreciated when reading the 3D axial dataset in interactive cine mode display. Conclusion Radiologists must be knowledgeable on liver vascular anatomy, its variants and the vascular landmarks allowing functional liver segmentation. . Angio-MDCT of the liver is often the standalone technique in the preoperative evaluation of patients for a variety of different clinical scenarios. Routine use of advanced post-processing algorithms and segmentation techniques such as maximum intensity projec-

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tions and three-dimensional volume renderings provide high quality graphic display which assists in the demonstration and understanding of its variable liver blood supply. “Nonportal” venous supply to the liver can mimic focal liver pathology and the exact location of the parenchymal abnormalities anticipates interpretative pitfalls. Although a single, worldwide-accepted classification of the liver anatomy does not exist, radiologists should favor the use of the terminology provided by the segmentation-based functional anatomy of the liver.

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VASCULAR LIVER ANATOMY AND MAIN VARIANTS — SECO et al 27. Chevallier P., Oddo F., Baldini E., Peten E.P., Diaine B., Padovani B. Agenesis of the horizontal segment of the left portal vein demonstrated by magnetic resonance imaging including phase-contrast magnetic resonance venography. Eur Radiol, 2000, 10: 365-367. 28. Morgan G., Superina R. Congenital absence of the portal vein: two cases and a proposed classification system for portosystemic vascular anomalies. J Pediatr Surg, 1994, 29: 1239-1241. 29. Soyer P., Heath D., Bluemke D.A., et al. Three-dimensional helical CT of intrahepatic venous structures: comparison of three rendering techniques. J Comput Assist Tomogr, 1996, 20: 122-127. 30. Lerut J.P., Mazza D., Van Leeuw V., et al. Adult liver transplantation and abnormalities of splanchnic veins: experience in 53 patients. Transpl Int, 1997, 10: 125-132. 31. Donato P., Coelho P., Rodrigues H., Vigia E., Fernandes J., CaseiroAlves F., Bernardes A. Normal vascular and biliary hepatic anatomy: 3D demonstration by multidetector CT. Surg Radiol Anat, 2007, 29: 575-82. 32. Erbay N., Raptopoulos V., Pomfret E.A., Kamel I.R., Kruskal J.B. Living donor liver transplantation in adults: vascu-

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41. Bernardes A., Coelho P., Ferreira S., Patrício J. Branches segmentaires de la veine porte: variations et localisation de l’origine – étude anatomique et par imagerie. E-mémoires de l’Académie Nationale de Chirurgie, 2007, 6: 72-76. 42. Fasel J.H.D., Gailloud P., Grossholz M., Bidaut L., Probst P., Terrier F. Relationship between intrahepatic vessels and computer-generated hepatic sissurae: an in vitro assay. Surg Radiol Anat, 1996, 18: 43-46. 43. Nelson R.C., Chezmar J.L., Sugarbaker P.H., Murray D.R., Bernardino M.E. (1990) Preoperative localization of focal liver lesions to specific liver segments: utility of CT during arterial portography. Radiology, 1990, 176: 89-94. 44. Soyer P, Roche A. Gad M et al. Preoperative segmental localization of hepatic metastases: ulility of threedimensional CT during arterial portography. Radiology, 180: 653-658. 45. Rieker O, Mildenberger P, Hintze C, Schunk K, Otto G, Thelen M Segmentanatomie der Leber in der Computertomographie: Lokalisieren wir die Lasionen richtig. Rofo, 2000, 171: 147-152.

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DETACHABLE COILING FOR EMBOLOTHERAPY OF HIGH-FLOW PULMONARY ARTERIOVENOUS MALFORMATION: CASE REPORT AND REVIEW OF THE LITERATURE M. Laureys1, P. Mendes da Costa2, L. Divano1 Pulmonary arteriovenous malformations (PAVMs) are very rare anomalies of the lung parenchyma. Although many patients are asymptomatic, it carries a high risk of severe cerebral complications, and rarely fatal outcome due to rupture of the malformation. There is a strong association with the Rendu-Osler-Weber disease. The patients should be treated in case of symptomatic PAVMs (paradoxical emboli), and also preventively, when the feeding artery is at least 3 mm in diameter. Embolization is a well-established treatment, which can be very challenging when dealing with very high-flow fistulas, where there is a risk of inadvertent migration of the embolization material in the left cavities of the heart and in the aorta. This report emphasizes the importance of the diagnosis and the embolization indication in pulmonary arteriovenous malformations, and the usefulness of detachable coils in case of high-flow fistulas. Key-words: Arteriovenous malformations – Embolism, pulmonary.

Case report A 72-year-old man was treated for sigmoid adenocarcinoma, staged T2N0. A routine follow up chest radiograph, showed a round nodular lesion in the right lower-lobe (Fig. 1). Chest Angio-CT scans demonstrated an artery-to-vein pulmonary fistula, with a very large associated aneurysm (Fig. 2). No cardiac or cerebral complications were present. The diameter of the arterial feeder (6.6 mm) and of the aneurysm indicated the need for a treatment. Embolization was performed under general anesthesia, by femoral vein puncture and catheterization of the right lower pulmonary artery. Then, an exchange for a 90 cm long 5 French flexible introducer sheath (Flexor Shuttle-SL®, William Cook Europe Aps, Bjaeverskov, Denmark) was performed over a extra stiff guide wire (Amplatz TFE coated®, William Cook Europe Aps, Bjaeverskov, Denmark), in order to obtain a stable position. A 4 French catheter (vertebral, Optitorque®, Terumo Europe NV, Leuven, Belgium) was then advanced as close as possible to the origin of the aneurysm. A long detachable 0.035-inch coil of 12 mm diameter and 6 cm long (Jackson Detachable Embolization Coils Inconel-Mreye®, William Cook Europe Aps, Bjaeverskov, Denmark)

Fig. 1. — Chest X-Ray shows a vascular mass in the right lower lobe (arrow).

was then progressively pushed, until a safe and stable position could be obtained, before delivery (Fig. 3). Several 0.035-inch coils (one Nester® of 12 mm diameter and 14 cm long and two Nester® of 10 mm diameter and 14 cm long, Embolization Coils, and two Embolization Coils Inconel-Mreye®, William Cook Europe Aps, Bjaeverskov, Denmark) completed the occlusion (Fig. 4).

From: 1. Radiology Department, 2. Digestive, Thoracic and Laparoscopic Surgery Department, CHU Brugmann, ULB-VUB Brussels, Brussels, Belgium. Address for correspondence: Dr M. Laureys, M.D., Radiology Department, CHU Brugmann, Place A. Van Gehuchten, 4, B-1020 Brussels, Belgium. E-mail: marc.laureys@chu-brugmann.be

The control chest radiograph performed 6 months later showed no dislocation of the embolization material, and the control thoracic angio CT scan confirms good occlusion of the pulmonary arteriovenous shunt (Fig. 5). There was no complication related to the procedure. Discussion A PAVM presents as an abnormal communication between the arterial pulmonary tree and pulmonary veins. It may be simple (one feeding artery, one outflow vein) or complex (multiple feeders, potentially intercostals or bronchic (1, 2).

DETACHABLE COILING FOR TREATMENT OF PULMONARY AV MALFORMATION — LAUREYS et al

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Diagnosis

Fig. 2. — On angio CT scan, there is an intensely-enhanced pulmonary artery to vein malformation (arrow).

known as Rendu-Osler-Weber disease (4). Acquired causes of PAVMs include post-thoracic surgery or trauma, infections (tuberculosis, actinomycosis, schistosomiasis), long-standing cirrhosis, metastatic carcinoma, mitral stenosis, and systemic amyloidosis (1, 5). PAVMs are a potential source of complications, related to paradoxical embolism. It is due to the absence of a normal filtering capillary bed, that may led to serious cerebral sequelae in the cerebral circulation: these include stroke (18%), transient ischemic attacks (37%), cerebral abscess (9%), migraine (43%) and seizures (8%) (1, 6). Rarely, the abnormal vessels may rupture into the pleura, the bronchus, or the pulmonary parenchyma (7).

Chest radiography may show the classic feature of PAVM: a round or lobulated lesion, varying in size from 1 to 5 cm in diameter, generally located in the lower lobes (1). Contrast echocardiography (with intravenous injection of agitated saline to create microbubbles) is useful to establish the diagnosis of right-to-left shunt, but is inaccurate in quantifying the shunt fraction, which is done by radionuclide imaging, or far less costly, by the 100% Oxygen method (8). Angio CT scans (Multirow Detector Computed Tomography, with intravenous injection of iodinated contrast material) allows a high detection rate of PAVMs, especially when multiple. Remy et al. (9) compared pulmonary angiography with Angio CT and found significantly better detection of PAVM with Angio

Fig. 4. — The control angiograms shows the total occlusion of the PAVM.

B Fig. 3. — A-C. The selective pulmonary angiography depicts the malformation. We see the implantation of the first detachable coil followed by several Nester® coils (C).

A thin-walled aneurysm, or pseudoaneurysm, located on the venous side, is often associated (3). 60 to 90% of pulmonary arteriovenous malformations (PAVMs) are associated with Hereditary Haemorrhagic Telengectasia, also

Fig. 5. — Control angio CT scan at the same levels, with no residual enhancement of the fistula.

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CT (98% versus 60% with pulmonary angiography). If a surgical or endovascular treatment is planned, digitally subtracted pulmonary angiography is required to obtain detailed information about the angioarchitecture, the morphology and the complexity of the PAVM (10).

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sible loss of pulmonary parenchyma surrounding the PAVM, and the longer hospital stay (3). Surgical resection is thus indicated in cases of intrapleural rupture or lesions not amenable to embolotherapy (8), although up-to-date embolization technique and material lead to successful occlusion in the near-totality of the patients.

Treatment Complications All symptomatic PAVMs must be treated, even when small, as morbidity in untreatred patients is high (50%) compared to the treated patients (3%) (11). When the feeding artery is greater than 3 mm in diameter, embolization is indicated in order to prevent the patient from complications (strokes and brain abscess) (12). Portsmann first reported embolotherapy for PAVM (13). Embolization can be performed with various materials, but polyester fibers platinum coils are generally used. It is mandatory to perform all exchanges “underwater”, to prevent air from going through the PAVM during the procedure. In high-flow fistulas, a detachable balloon may be implanted, but this latter is very expensive. Inflation of an occlusive balloon is an alternative; it allows the deployment of the coils and prevent their migration (3). However, it is not always applicable and is rather unsafe as a migration risk still exists during the balloon deflation and retrieval. More recently, detachable coils have been available. The device helps the interventional radiologist to deploy the first “security” loops progressively and safely, without threatening from the rapid flow. The deployment is done as close as possible to either the site of the fistula, or the aneurysmal sac. Other “conventional” coils can then be pushed into this nest, in order to achieve the occlusion. The first successful surgical resection of a PAVM was reported in 1942 (14). Nowadays, lung conservative surgery and thoracoscopic assisted techniques are described, that however carry the complication risk of all other thoracic surgery procedures. Disadvantages also include the pos-

They are encountered in less than 10% of the patients, and include localized and short-lasting pleurisy, pulmonary infarction distal to the occlusion, sepsis, and retrograde pulmonary embolism in case of polycythaemia (12). Results Immediate closure is achieved in 98% of the cases (12). The long term follow-up shows a recanalization potential of the embolized site in about 8% of all the PAVMs (3, 15), and is not related to the embolization material (balloons or coils). Several studies show recanalization rates varying from about 3% to more than 20% (3), and is significantly higher when multiple PAVMs are present, and when all the visible PAVMs are not embolized (3). Thus, new PAVMs may appear during the follow-up period, requiring new possible embolizations. The lack of clinical response to occlusive or surgical therapy is related to the severity of the pulmonary disease (multiple PAVMs) (3). Conclusion Even when they are treated, they must be watched closely with thoracic angio-CT scans, as recanalization or new PAVMs may occur. Embolotherapy remains a safe and efficient therapeutic method, carrying a very low complication rate, and has many advantages over surgery. If the PAVM is a high-flow lesion, embolization can be performed with detachable coils, which allow a safe and stable first nest deployment. References 1. Khurshid I., Downie G.H.: Pulmonary arteriovenous malformation. Postgrad Med J, 2002, 78: 191-197.

2. Pelage J.P., El Hajjam M., Lagrange C., Chinet T., Vieillard-Baron A., Chagnon S., Lacombe P.: Pulmonary artery interventions: an overview. Radiographics, 2005, 25: 1653-1667. 3. Mager J.J., Overstoom T.T.C., Blauw H., Lammers J.W.J., Westermans C.J.J.: Embolotherapy of pulmonary arteriovenous malformations: long-term results in 112 patients. J Vasc Interv Radiol, 2004, 15: 451-456. 4. White R.J. Jr., Pollak J.S., Wirth J.A.: Pulmonary arteriovenous malformations : diagnosis and transcatheter embolotherapy. J Vasc Interv Radiol, 1996, 7: 787-804. 5. Coley S.C., Jackson J.E.: Pulmonary arteriovenous malformations. Clin Radiol, 1998, 53: 396-404. 6. Shovlin C.L., Letarte M.: Hereditary haemorrhagic telangectasia and pulmonary arteriovenous malformations: issues in clinical management and review of pathogenic mechanisms. Thorax, 1999, 54: 714-729. 7. Gossage J.R., Ghassan K.: Pulmonary arteriovenous malformation: a stateof-the art review. Am J Respir Crit Care Med, 1998, 158: 643-661. 8. Ibqal M., Rossoff L.J., Steinberg H.N., Marzouk K.A., Siegel D.N.: Pulmonary arteriovenous malformations: a clinical overview. Postgrad Med J, 2000, 76: 390-394. 9. Remy J., Remy-Jardin M., Wattinne L., et al.: Pulmonary arteriovenous malformation: evaluation with CT of the chest before and after treatment. Radiology, 1992, 182: 809-816. 10. Remy J., Remy-Jardin M., Giraud F., et al.: Angioarchitecture of pulmonary arteriovenous malformations: clinical utility of three-dimensional helical CT. Radiology, 1994, 191: 657-664. 11. Puskas J.D., Allen M.S., Moncure A.C., et al.: Pulmonary arteriovenous malformations: therapeutic options. Ann Thorac Surg, 1993, 56: 253-258. 12. Ghaye B., Dodelinger R.F.: Imaging guided thoracic interventions. Eur Respir J, 2001, 17: 507-528. 13. Portsmann W.: Therapeutic embolization of arteriovenous pulmonary fistulas by catheter technique. In: Kelop O., ed. Current concepts in pediatric radiology. Berlin, Springer, 1977, pp 23-31. 14. Hepburn J., Dauphinee J.A.: Successful removal of hemangioma of lung followed by disappearance of polycythemia. Am J Med Sci, 1942, 204: 681-687. 15. Lee D.W., White R.I., Egglin T.R., et al.: Embolotherapy of large pulmonary arteriovenous malformations: longterm results. Ann Thorac Surg, 1997, 64: 930-940.

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IMAGES IN CLINICAL RADIOLOGY CT imaging of ascaris lumbricoides F.C. Deprez, C. Pauls, T. Puttemans

A 37-year-old man was referred to the department of internal medicine for chronic fever, asthenia and loss of weight. He had no relevant medical history but reported frequent travels to Africa. Abdominal-CT study with contrast agent injection and oral digestive opacification was performed and revealed pleuroperitoneal and pericardial effusions with multiple mediastinal and mesenteric lymphadenopathies. Bronchoalveolar lavage and sputum expectoration analyses demonstrated systemic tuberculosis. Moreover, CT series fortuitously revealed a tubular defect in the contrast filled lumen of the ileum. The abnormal structure measured around 25 cm in length and 0.4 cm in width (Fig. A frontal view, thick minIP reconstruction), with a central thin white line (Fig. B,C - axial views - arrows). These features were very suggestive of an intestinal worm, most likely Ascaris lumbricoides (AL), without any link with his symptoms and his tuberculosis infection. The central thin white line corresponding to ingested barium in worm gut. Comment

AL is a rounded intestinal worm characterized by its great size (males are 2-4 mm in diameter and 15-31 cm long, females are 36 mm wide and 20-49 cm long). AL is the most common human intestinal parasite and infects about a quarter of the world population, but is quite rare in western European population. Most patients are asymptomatic; however AL occasionally provokes poorly localized cyclic abdominal pain in adults. In children, volvulus, intussusception or intestinal obstruction may occur. Occasionally, the adult Ascaris worm may migrate into the Vaterâ&#x20AC;&#x2122;s ampulla and enter the bile duct, gall bladder or pancreatic duct, leading to a variety of complications such as biliary colic, gallstone formation, cholecystitis, pyogenic cholangitis, liver abscess and pancreatitis. Infection occurs with AL eggs contaminated water or food. Larval worms penetrate the wall of the duodenum and migrate by venous or lymphatic circulation to pulmonary arterioles and alveoli to grow. After 3 weeks, the larvae pass from the respiratory system to be coughed up, swallowed, and thus returned to the small intestine where they mature to adult male and female worms. AL can be observed on CT and RX with oral digestive opacification, but also on MRI series or ultrasonographic exams. MRCP sequences reveal hypointense elongated tubular filing defect in hyperintense intestinal fluid. High-frequency sonographic transducer can reveal typical long echogenic structure with four parallel echogenic lines, corresponding to the outlines and the gut of the worm. Prove diagnosis of AL infection is obtained by stools analyses, identifying ova and parasites. Treatment on the AL consisted on oral administration of Mebendazole (100 mg, 2 doses a day for three days).

C Department of Radiology, Clinique St-Pierre, Ottignies-LLN, Belgium.

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IMAGES IN CLINICAL RADIOLOGY An uncommon cause of asyptomatic crazy paving pattern: exogenous lipoid pneumonia C. Schoofs, L. Bladt, W. De Wever

A 54-year-old man presented at our department complaining of chest wall pain with clinical suspicion of rib fractures. Neither the clinical examination, the medical history of the patient nor the laboratory findings revealed any abnormalities. The patient mentioned chronic use of TrazolanÂŽ (trazodon). A chest X-ray (PA & lateral) was performed and revealed several posttraumatic rib fractures. There was also a patchy distribution of consolidations in the postero-basal segment of the right lower lobe, as well as in the basal segment of the right middle lobe (Fig. A). Those patchy consolidations were also present on a preceding chest film, obtained 2 years before date, but the consolidation had clearly gained in volume and density. Spiral chest CT showed a crazy-paving pattern. There were diffuse ground-glass opacities with superposition of thickened inter- and intralobular septa and interlobular lines. In both lower lobes there was also superposition of consolidation areas. There was relative sparing of the subpleural space (Fig. B, C). Since these radiologic findings could be part of a medicamentousinduced chronic eosinophilic pneumonia, an etiologic link was suspected with Trazolan and the use of this product was aborted without any results. Subsequent chest imaging showed no improvement after six weeks, even though the patient was completely asymptomatic. Lung biopsies were obtained, revealing definite deposition of lipid drops surrounded by histiocytes and at some point organizing in lipid-granulomas, with a surrounding lymphocytary infiltrate. These pathologic findings correlate with a lipoid pneumonia. At specific anamnestic questioning it appeared that the patient had been using decongestant nose drops for a long period in large amount. Paraffin-containing nose drops are the most common cause of exogenous lipoid pneumonia. Comment

Lipoid pneumonia is an uncommon condition resulting from chronic aspiration of mineral, animal or vegetal oils into the lungs. Once inhaled, the oil is phagocytosed by macrophages that fill the alveoli and distend the alveolar walls, causing acute and chronic pneumonitis. Over time, the macrophages transport the oil from the alveoli to the interlobular septa, resulting in localized granulomas and pulmonary fibrosis. Pathologically, exogenous lipoid pneumonia is characterized by the presence of giant cell granulomas, alveolar and interstitial fibrosis, and chronic inflammation. Symptoms are nonspecific and may include progressive dyspnea, cough and even hemoptoe, though the affected individual can also be asymptomatic, as proven by our case. Conventional radiography can show airspace consolidation, an irregular mass-like lesion or a reticulonodular pattern. The most common locations for lipoid pneumonia are the dependent portions of the lung. The characteristic finding on CT of the chest is lung consolidation with fat attenuation, but a crazy paving pattern with ground-glass opacification with superposition of septal thickening and centrilobular interstitial thickening as in our case has also been described. The diagnosis is most often made based on a combination of radiographic and clinical features, long-term stability and the absence of other causes of pulmonary disease. Treatment involves discontinuation of the offending agent and radiographic follow-up to ensure stability. Although lipoid pneumonia is an unusual cause of chronic lung disease, it is an important consideration in the differential diagnosis of several pulmonary syndromes because progression is halted, or at least slowed, by stopping exposure to the offending lipid substance.

Department of Radiology, UZ Gasthuisberg, Leuven, Belgium.

JBRâ&#x20AC;&#x201C;BTR, 2010, 93: 229.

IMAGES IN CLINICAL RADIOLOGY Mycotic aneurysm of the superior mesenteric artery W. Siemons1, S. Heye1

A 50-year-old male presented with nonspecific complaints of orthostatism and presyncope of 3 months duration and reported a weight loss of 6 kg in 3 weeks. Blood tests showed inflammatory biochemical results (CRP of 86 mg/dl, normal leucocytosis). Hemocultures were positive for Streptococcus Mutans. Echocardiography was performed showing large vegetations on the aortic valve. The diagnosis of infectious endocarditis was made. Ultrasound of the abdomen to evaluate the abdominal aorta and its side-branches, demonstrated an aneurysmal dilatation (11 mm wide âŤť 16 mm long) of the superior mesenteric artery (A). MDCT-angiography (B, C) showed an aneurysm in the distal part of the superior mesenteric artery, with mural thrombus and slight infiltration of the surrounding mesenteric fat. These imaging finding were diagnostic for a mycotic aneurysm, as a complication in infectious endocarditis. The patient was treated with intravenous antibiotics for 6 weeks. Because of severe insufficiency of the aortic valve and the large vegetations, aortic valve plasty was performed. The aneurysm of the superior mesenteric artery was not resected because of its distal position which would require complex vascular surgery. Follow-up MDCT-angiography after 1 week showed a complete thrombosis of the aneurysm. Comment

Aneurysmal pathology of the superior mesenteric artery (SMA) is rare. Among visceral aneurysms, those of the SMA account for 5.5-8%. Most SMA aneurysms are of mycotic etiology (60%), whereas those because of atherosclerosis are less common, although their frequency has risen in the past years. In our case, the mycotic SMA aneurysm resulted from a septic aortic valve. Most aneurysms are symptomatic, causing upper abdominal pain because of their compressive mass effect on contiguous structures. In some cases, typical signs of abdominal angina are present. MDCT-angiography is most accurate for diagnosis and is also very useful for finding other lesions, such as abscesses. Although rare, SMA aneurysms can definitely rupture, particularly in persons at high risk. Male patients and patients with non-calcified aneurysms appear to have the greatest risk of rupture. Reports in the literature describe lesional dimensions ranging from 4 to 8 cm. Intervention is reasonable in all patients with SMA aneurysms, if they are good surgical candidates. Treatment normally consists of bowel resection and ligation of the mycotic aneurysm. Because of the fact that small aneurysms of the SMA are unlikely to rupture, they can be managed with a trial of intravenous antibiotics for 4-6 weeks along with surveillance imaging, as in our case. Enlarging or residual aneurysms at surveillance imaging should be triaged to surgical management.

1. Department of Radiology, University Hospitals Leuven, Leuven, Belgium.

JBRâ&#x20AC;&#x201C;BTR, 2010, 93: 230.

IMAGES IN CLINICAL RADIOLOGY Bithalamic Percheron

acute

stroke:

artery

F.C. Deprez, P. Bosschaert, X. Leysen1

A 44-year-old man without medical history was admitted to the emergency room in a coma. He had not reported work and was discovered lying on the ground of his home in the evening by his brother. The initial Glasgow Coma Scale score was a 5. Head CT study without contrast agent injection was performed and revealed well delimited bithalamic central hypodensities (Fig. A1, axial view, stars in the paramedian thalami), suggestive for sub-acute ischemic lesions. MRI series showed high diffusion and FLAIRweighted signal of the two paramedian thalami and of the internal side of the left occipital lobe confirming recent ischemic lesion (Fig. A2, FLAIR-weighted frontal view, Fig. B1, Diffusion-weighted axial view). Time-of-flight (TOF) magnetic resonance angiography well demonstrated distal amputation of the left posterior cerebral artery (PCA), due to acute thrombosis or embolic occlusion (Fig. B2, arrow on the normal right PCA, arrowheads on the amputated left PCA). Bithalamic infarction was attributed to an anatomic variation: a common trunk for the two thalamic paramedian arteries, concerned by the PCA obstruction. The patient benefited from antiaggregant treatment by acetylsalicylic acid. Tracheotomy and gastrostomy were also necessary. Consciousness partial recovery was observed in the patient two days after admission. Comment

Thalami are composed of six nuclei (intralaminar, dorsomedial, ventrolateral, ventroanterior, ventroposterior and posterior nuclei). They are vascularized by four major thalamic arteries, each with a predilection for supplying particular groups of nuclei: the tuberothalamic, inferolateral, paramedian and posterior choroidal arteries. Paramedian bithalamic infarctus is cause by the obstruction of a common trunk for the thalamic paramedian artery, unusual anatomic variation of the thalamo-mesencephalic vascularization. Paramedian artery arises from the P1 section of the posterior cerebral artery (also called mesencephalic artery from the bifurcation of the basilar to its junction with the posterior communicating artery), and irrigates paramedian thalamic territories but may occasionally assume tuberothalamic artery territory (absent in one-third of cases). Different anatomic patterns can be observed (Fig. C): paramedian arteries can arise from each P1 (type 1), can arise in pair from one P1 (type 2a) or can arise of a common trunk from one P1 (type 2b), causing bithalamic stroke in case of common trunk obstruction. Paramedian artery and superior mesencephalic artery (irrigating pons and mesencephale) can equally arise from a common trunk, which can lead to dramatic thalamico-mesencephalic stroke. These anatomic variations must be known in order to understand unusual imaging findings.

1. Department of Radiology, Clinique St-Pierre, Ottignies-LLN, Belgium.

JBR–BTR, 2010, 93: 231-232.

LETTER TO THE EDITOR N. Campbell, J. Feeney1

We read great interest the recent case report and discussion on the topic of gallstone ileus in the JBR-

BTR (1). We would like to add our experience with fistulating gallbladder disease as we have had two

quite unusual cases recently of older patients presenting with this rare complication of cholelithiasis.

Fig. 1. — A. Coronal reformatted contrast-enhanced CT abdomen showing large laminated gallstone in the gallbladder (black arrow) and fluid collection in the right anterior abdominal wall, with enhancing rim (white arrow). B. Coronal reformatted image from the same patient showing a fistulous tract (orange arrow) extending from the gallbladder (small white arrow) to the abdominal wall collection (large white arrow).

Fig. 2. — Coronal reformatted contrast-enhanced CT showing air within the common bile duct (small white arrow). Air is also demonstrated within the gallbladder, which is thick walled (black arrow) and fistulating directly into the adjacent gastric antrum (large white arrow). 1. Department of Radiology, Adelaide and Meath Incorporating the National Children Hospital, Dublin, Ireland

The first patient is an 81 year old lady, of increased BMI and with a constellation of medical complaints including known chronic cholecystis. She presented to the surgical outpatient department with a hard, palpable mass in her right upper quadrant that had been enlarging over the previous year. Contrast-enhanced CT abdomen revealed a 10 cm ⫻ 10 cm multiloculated, fluid filled collection within the abdominal wall muscles, extending into the subcutaneous tissues, directly adjacent to the gallbladder (Fig. 1). Also noted was a single large, laminated gallstone in the gallbladder. The collection was drained under ultrasound guidance in the radiology department and once CT abdomen showed resolution of the collection, the patient was brought to theatre for a laparoscopic cholecystecomy. Intraoperatively, a fistulous tract was identified extending from the fundus of the gallbladder to the abdominal wall collection.

232

The second patient is an 81 year old man with mulitple co-morbidities, who, while undergoing investigation of symptomatic anaemia, was noted to have pneumobilia on hepatobiliary ultrasound. Contrastenhanced CT abdomen showed a cholecystogastric fistula, pneumobilia and four calculi in the distal common bile duct (Fig. 2). The treatment of this condition is typically surgical, and there is increasing experience in the literature of using a laparoscopic approach. This patient was not a suit-

JBRâ&#x20AC;&#x201C;BTR, 2010, 93 (4)

able candidate for surgery and so underwent ERCP with removal of the common bile duct stones, a technique that has been used with success in such patients, allowing closure of the fistula by decreasing the biliary pressure (2). This patient is clinically doing very well since this procedure. As the author of the recent article in JBR-BTR describes, fistulating gallbladder disease is a rare complication of cholelithiasis. CT is the imaging modality of choice in

making the diagnosis, as evidenced by the images obtained in our cases above. References

Willekens I., Verdries D., Ceulemans G., Vandenbroucke F, Delvaux G, de Mey J. Gallstone Ileus. JBR-BTR, 2010, 93: 4-6. 2. Goldberg R.I., Phillips R.S., Barkin S.J. Spontaneous cholecystocolonic fistula treated by endoscopic sphincterotomy. Gastrointest Endosc, 1988, 34: 55-56.

JBR–BTR, 2010, 93: 233-234.

FORTHCOMING COURSES AND MEETINGS CALENDRIER NATIONAL – NATIONAAL KALENDER 02-04.09.10 BREAST IMAGING – A COMPREHEN SIVE REVIEW MEETING Bruges, Belgium 9-12.09.10 17TH SYMPOSIUM ON UROGENITAL RADIOLOGY Main topic: Imaging and focal therapy Bruges, Oud Sint-Jan Information: raymond.oyen@uzleuven.be 10.09.10 BELGIAN MUSEUM OF RADIOLOGY 20TH ANNIVERSARY SYMPOSIUM VIOLENCE AND IMAGING Information: www.rbrs.org 11.09.10 FIRST SKULL BASE DAY Wilrijk, St Augustinus Hospital 13.09.10 SRBR – Section Neuroradiologie KBVR – Sectie Neuroradiologie Brussels, UCL Information: Duprez@uclouvain.be – philippe.demaerel@uzleuven.be 17.09.10 SRBR – Section Radiologie Cardiovasculaire et Interventionelle KBVR – Sectie Cardiovasculaire en Interventionnele Radiologie Antwerpen, UZA Information: luc.defreyne@ugent.be and Marc.Laureys@chu-brugman.be

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Annual RBRS Symposium 20.11.10

SRBR – Section Ostéo-articulaire KBVR – Sectie Osteo-articulaire Beedlvorming 16.10.10

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JBR–BTR, 2010, 93 (4) 28-11-2010 RADIOLOGICAL SOCIETY OF NORTH AMERICA ANNUAL MEETING 2010 Information: http://rsna2010.rsna.org/ 09-11.12.10 COURS INTENSIFS DE TDM MULTICOUPE DU THORAX Lille, France Information: secrétariat du Serv. de Radiologie, Hôp. Calmette, Bld du Pr Leclerc, F-59037 Lille Cedex Tel.: 03-20-44 43 11 Fax: 03-20-44 47 20 e-mail: mremy-jardin@chru-lille.fr 10.02.11 JOINT INTERVENTIONAL MEETING Rome, Italy Information: www.jim-vascular.com 23.02.11 ANNUAL SYMPOSIUM OF THE AMERICAN SOCIETY OF SPINE RADIOLOGY 2011 USA, Hawaii Information: http://theassr.org

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