YIA Winner 2012 Abstract

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young investigator’s Award EUROSON 2012 Madrid, Spain 23 April 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

COUNTRY

NAME OF NOMINEE TITLE OF ABSTRACT

AUSTRIA

Ralph Faschingbauer

Meralgia paresthetica: Ultrasound guided injection with 12 month follow-up data

THE NETHERLANDS Hendrik H.G. Hansen

Non-invasive compound elastography of carotid arteries: in patient validation

DENMARK

Ditte Dencker

Drainage of poorly visualized areas guided by image fusion involving ultrasound and electromagnetic needle tracking – initial experience

UNITED KINGDON

Ankur Thapar

Dose-dependent artefact in the far wall of the carotid artery with dynamic contrast enhanced ultrasound

ROMANIA

Mihai Adrian Socaciu

Perfusion quantification in treated hepatocellular carcinoma using CEUS

ITALY

Manuela Marzo

New prototypes of microbubbles: in vitro evaluation of their reflectivity using Qontrast software

SLOVENIA

Ksenija Vukovic

Can contrast-enhanced ultrasound characteristics help in differentiation between focal nodular hyperplasia and hepatocellular adenoma

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young Investigator’s Award EUROSON 2012 Madrid, Spain 23 April 2012 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

Meralgia paresthetica: Ultrasound guided injection with 12 month follow-up data

R. Faschingbauer, C. Siedentopf, G. Feuchtner, M. Sojer, W. Jaschke, A. Klauser University Hospital Innsbruck, Austria

ABSTRACT: Objective To evaluate the efficacy of ultrasound guided injections around the lateral femoral cutaneous nerve (LFCN) in patients complaining of meralgia parestetica nocturna, and to document long term results at 12 months.

Materials and Methods This HIPPA compliant study was approved by our local Institutional Review Board; informed oral and written consent were obtained. Between 2008 and 2011, n=17 patients with symptoms of meralgia paresthetica nocturna, including 8 men (mean age, 61.38 years; range 47-70 years, SD: 9.16) and 9 women (mean age 61.57 years; range 46-75 years, SD: 8.60) were treated with US guided injection of steroids along the LFCN. A visual analog scale (VAS) measure of symptoms before treatment and after 12 month was compared.

Results Complete resolution of symptoms was documented in 12/17 patients (70.6%; 95% CI [0.44, 0.90]) and partial resolution in the remaining 5. These patients remained symptom-free or maintained their symptomatic improvement at 12 month follow-up. When compared with historical controls (60% failure of treatment), our ultrasound guided technique resulted is statistically significant improvement in patient outcome (p< 0.05).

Conclusion US-guided injection of steroids along the LFCN in patients complaining of Meralgia paresthetica results in more frequent long-term improvement in symptoms as compared with historical controls treated by injection without ultrasound guidance.

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young Investigator’s Award EUROSON 2012 Madrid, Spain 23 April 2012 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

Non-invasive compound elastography of carotid arteries: in patient validation

H.H.G. Hansen 1, G.J. de Borst 2, G. Pasterkamp 2, C.L. de Korte 1 1. Radboud University Nijmegen Medical Centre, Nijmegen, the Netherlands 2. University Medical Centre Utrecht, Utrecht, the Netherlands

ABSTRACT: Purpose To validate that the compound elastography technique we developed enables a noninvasive measurement of atherosclerotic plaque composition in carotid arteries [1].

Material and Methods Atherosclerotic carotid plaque rupture is one of the main causes of stroke. The rupture proneness of a plaque is related to its composition and geometry. To measure plaque composition, which cannot be determined using regular B-mode ultrasound, an elastography technique was developed which combines ultrasound radiofrequency data obtained at three different insonification angles (0°, +20 and -20 degrees). In this study the method was applied in vivo to 18 severely stenotic carotid arteries of symptomatic patients before endarterectomy (surgical excision of the plaque and inner vessel wall). A Medison Accuvix V10 ultrasound system equipped with an L5-13 linear array transducer and dedicated software was used for the multi-angle acquisition. After endarterectomy segments of the imaged plaque crosssection were cut and histologically stained. Based on the staining the plaque was characterized as fibrous, fibro-fatty, or fatty and also the fibrous cap thickness, amount of smooth muscle cells (SMC) and macrophages weres determined. The correlation between these histological parameters and the percentage of plaque area with strain values above 2% was determined.

Results A significant correlation (Spearman’s rho, P<0.05) was observed between plaque type (fibrous, fibro-fatty and fatty) and the strain parameter. Furthermore, increased strain values were observed for plaques with a thinner fibrous cap and for plaques with a lower amount of SMCs. The amount of macrophages was not reflected by a change in strain values. However, for plaques with macrophages close to the lumen, higher strains were observed than for plaques with ‘deep’ macrophages.

Conclusions We demonstrated that compound elastography provided parameters that were related to plaque composition. A significant correlation with the plaque type was observed. Features that have been shown to be related to plaque vulnerability, like a thin fibrous cap [2], also increased the strain parameter, but did not reach significance due to the limited number of patients.

Literature References [1] H.H.G. Hansen, R.G.P. Lopata and C.L. de Korte, Phys. Med. Biol. (55) 3201â&#x20AC;&#x201C;3218, 2010 [2] A.V. Finn, M. Nakano, J. Narula, F.D. Kolodgie, R. Virmani, Arterioscler. Thromb. Vasc.

Biol. (30) 1282-1292, 2010

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young Investigator’s Award EUROSON 2012 Madrid, Spain 23 April 2012 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

Drainage of poorly visualized areas guided by image fusion involving ultrasound and electromagnetic needle tracking – initial experience

Ditte Dencker, Caroline Ewertsen, Steen Karstrup

ABSTRACT: Introduction Percutaneous drainage is often performed guided by ultrasound (US), which has the advantage of real time images. However, US is unable to visualize structures behind air and bone. The challenges in such areas may be overcome by using image fusion, where a previously recorded CT or MRI examination is co-registered with real time US. Methods Image fusion and electromagnetic needle tracking are based on a magnetic positioning system and can be used together or separately. An electromagnetic sensor is embedded in the needle tip and its virtual route of puncture is electronically and simultaneously displayed on both the US and the CT (or MRI) image.

We present our initial clinical experience in three patients, all having severe clinical conditions and pathology in areas with limited US overview.

Results All three patients were successfully treated by percutaneous US-guided drainage using image fusion (US/CT) and electromagnetic needle tracking. All patients avoided surgery. One patient had a severe pancreatic abscess located deep to air containing intestines, and two patients suffering from colon cancer had air-filled intraabdominal cavities due to anastemotic leak after hemicolectomy.

Conclusion We successfully evaluated image fusion using CT and US and electromagnetic needle tracking for US-guided percutaneous drainage in areas with limited US overview.

We are continuously evaluating the techniques in selected patients with promising results.

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young Investigator’s Award EUROSON 2012 Madrid, Spain 23 April 2012 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

Dose-dependent artefact in the far wall of the carotid artery with dynamic contrast enhanced ultrasound

A. Thapar 1, J. Shalhoub 1, C. Mannaris 2, A. H. Davies1, M. Averkiou 2, E. L. S. Leen1 1. Imperial College London, United Kingdom 2. University of Nicosia, Cyrpus

ABSTRACT: Purpose Dynamic contrast enhanced ultrasound (DCE-US) is an emerging technology to assess neovascularization in atherosclerosis. The aim of this study was to quantify a pseudoenhancement phenomenon observed during the DCE-US of the carotid artery both in-vitro and in-vivo.

Materials and Methods Ethical approval was obtained prior to commencing this prospective case series and each patient gave written informed consent to participate. 31 patients with 50-99% internal carotid artery stenosis underwent DCE-US imaging of the carotid bifurcation using 2 ml of intravenous SonoVue™. In the final 10 patients, an additional 1 ml bolus was administered after 15 minutes. Raw linear DICOM data was analysed offline. Regions of interest were drawn within the common carotid artery lumen and immediately adjacent to the lumen in the near and far wall adventitia. Peak intensity was measured. In addition, an in vitro experiment using a single channel flow phantom was performed. This in vitro apparatus consisted of an 8 mm diameter latex tube placed in a tissue-mimicking fluid. SonoVue™ concentrations of 0.02, 0.1, 0.5, 1, and 2 ‰ were pumped into the tube. Regions of interest were drawn in a similar fashion to the in vivo experiments and peak intensity measured. The Wilcoxon signed rank test and paired t-tests were used to compare the difference between the near and far wall intensities at each dose; a multiplication factor comparing near- and far wall intensity was derived.

Results The far wall of the common carotid artery was significantly more echogenic than the near wall at 2ml contrast doses (p<0.0001, n=31), and the far wall intensity rose synchronously with that of the lumen. The intensity difference between near and far wall regions was significantly

greater at 2 ml than 1 ml (p=0.012, n=10). In vitro, the phantom tubing demonstrated a similar pattern and magnitude of enhancement to that seen in vivo.

Conclusion A dose-dependent, non-linear propagation artefact, which we term â&#x20AC;&#x153;pseudo-enhancement,â&#x20AC;? occurs in the far wall adventitia of the carotid artery, which should not be mistaken as a marker of plaque vulnerability.

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young Investigator’s Award EUROSON 2012 Madrid, Spain 23 April 2012 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

Perfusion quantification in treated hepatocellular carcinoma using CEUS Mihai Socaciu, Radu Badea, Angela Parau Medicala III Clinic, Cluj-Napoca, Romania

ABSTRACT: Introduction It is known that the response to the anti-angiogenic drugs is reflected not by a shrinkage in size, but by the appearance of necrotic areas inside the tumor and by a decrease in blood perfusion. With the advent of the second generation ultrasound contrast agents, it is now possible to assessthe amount of filling in the capillaries (the perfusion). Although the necrosis volume can be subjectively assessed using CEUS, it can hardly be used as a criteria of response, since it is not very repeatable. However, perfusion could be quantified using the “time-intensity curves” (TIC), a feature found on most modern ultrasound machines.

Material and Method 18 consecutive patients with advanced stage hepatocellular carcinoma treated with Sorafenib were followed up in our clinic. All the patients had a positive hystopatological diagnosis and most of them had at least one CT performed. The CEUS examination was performed on a GE Logiq 7 machine with a broadband 1,5-5,5 MHz probe. Through the B-mode US, the general location and characteristics of the tumors were described. If there were more tumors, the most accessible one was chosen for CEUS and follow-up. The machine was set in the Harmonic Coded Contrast mode with Pulse Inversion, using lower mechanical indexes (MI) between 0,07-0,12. After the bolus injection of contrast (2,8 ml SonoVue, followed by 10 ml saline), at least two clips 30 s long were captured. TIC curves were traced using a specialized software (SonoLiver, Bracco), after joining the clips, with ROIs located inside the tumor and the surrounding parenchima for reference. The following parameters were obtained and compared: time to peak (TTP), peak intensity (PI), ascension time (AT), transit time (TT), while the area under the curve (AUC) was obtained by post-processing the data on a mathematical software (Origin).

Results 10 out of the 18 patients showed areas of necrosis inside their tumors (evidenced by the lack of contrast in the arterial phase) after the treatment. This correlated with the stationary size (no more than 5% growth in volume). Necrosis appearance was in agreement with the CT

examinations. No relevant information could be obtained from the Doppler examination. The shape of the TICs from the tumor generally showed less elevation after treatment, which corresponded in lower PIs, longer TTPs and lower AUCs. Conclusion CEUS can be a good method to assess the perfusion of the treated hepatocellular carcinomas. Unlike the CT, dynamic studies are easy to conduct using US, with real-time frame rates and no irradiation. The perfusion indexes obtained by TIC post-processing (especially TTP and AUC) can assess the effectiveness of the anti-angiogenic treatment and increase the confidence in the diagnosis.

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young Investigator’s Award EUROSON 2012 Madrid, Spain 23 April 2012 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

New prototypes of microbubbles: in vitro evaluation of their reflectivity using Qontrast software Marzo M, Virgilio G, Sanna V, Scanu D, Pintus G, Sirigu D, Uzzau S, Sechi M, Migaleddu V.

ABSTRACT: Aims To evaluate in vitro, using ultrasound, the reflectivity of new prototypes of microbubbles (MBs) containing air, with the shell of different biocompatible and biodegradable copolymers: polylactic acid (PLA), poly-glycolic-lactic acid (PGLA), and PGLA conjugated with poly-ethyleneglycol (PGLA-PEG).

Material and Methods Using an experimental model of degassed and deionized water, each sample of MBs, was evaluated with a 3.5-4 MHz convex probe (Sequoia Acuson-Siemens). Ultrasound imaging was obtained using a contrast-specific software (Cadence Contrast Pulse Sequencing). A quantitative analysis of the echoes intensity was performed through the specific Qontrast software (Advanced Medical Imaging Development, Bracco, Italy), selecting manually a region of interest.

Results The intensity of signal produced by the different MBs has been compared to that of water.

Each MBs prototype demonstrated a signal related to coating composition. Signal intensity increased in the order PLA < PLGA < PLGA-PEG, in particular 15+/-0,08%, 18+/-0,9% e 34+/1,8%, respectively, obtaining a significant statistical correlation (p<0.05).

Conclusions MBs with shell of PLGA-PEG resulted the most effective in terms of reflectivity after exposure to ultrasound. So they might be further optimized and used as potential carriers for selective drug delivery.

EFSUMB EUROPEAN FEDERATION OF SOCIETIES FOR ULTRASOUND IN MEDICINE AND BIOLOGY ‘Building a European Ultrasound Community’ Young Investigator’s Award EUROSON 2012 Madrid, Spain 23 April 2012 11.30 – 13.00 9 minutes each for presentation plus 3 minutes discussion

Can contrast-enhanced ultrasound characteristics help in differentiation between focal nodular hyperplasia and hepatocellular adenoma Ksenija Vukovic, Mirjana Brvar, Sasa Rudolf University Medical Centre Maribor, Slovenia

ABSTRACT: Objectives New knowledge in radiologic characteristics has improved the diagnostic accuracy in increasing number of incidentally discovered benign liver lesions in the last years, but the differentiation between focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) still brings challenge to radiologists.

Material and methods Retrospectively we examined CEUS characteristics from seventeen patients diagnosed by magnetic resonance imaging (MRI) or proven histologically to have either FNH (n=11) or HCA (n=6). Image files were analysed for enhancement pattern in the arterial, portal and late phase, for filling direction, central scar, spoke-wheel pattern and for the transient peripheral unenhanced zone.

Results Hypervascularity in the arterial phase was observed in all lesions, there was no significant difference in the onset of enhancement; FNH mostly showed more prominent enhancement.

In the portal phase 9/11 FNH were isoechoic, two were hyperechoic; from HCA one was hyperechoic, two isoechoic and 3/6 were slightly hypoechoic (50%). Except from three HCA that were hypoechoic in the late phase, all other lesion were isoechoic. Highest specificity in the differentiation between FNH and HCA showed the analysis of filling direction. Except from one case of FNH and regardless of size, which ranged from 12 to 115 mm, characteristic centrifugal filling pattern was noticed (10/11 [91%]); all HCA showed centripetal filling (6/6 [100%]). Considering central scar to determine FNH displayed low sensitivity and low specificity ([60%] and [27%], respectively); regarding CEUS 3/11 FNH had central scar, and assessing MRI 5/11 FNH exhibited central scar. Due to fast enhancement of FNH, and especially in lesions smaller than 2 cm, it is difficult to acknowledge the spoke-wheel pattern due to fast enhancement, thus this pattern was seen in only 7/11 FNH ([64%]). If seen, the transient peripheral unenhanced zone can help confirm the diagnosis of FNH; in our study 4/11 FNH presented with transient peripheral unenhanced zone in the arterial phase ([36%]); in none of HCA this characteristic could be depicted.

Conclusions Improved definition of CEUS characteristics enables more accurate identification between FNH and HCA. Among these characteristics, filling direction has the highest specificity for diagnosis, as demonstrated in our study, thus CEUS technique with the possibility of real time imaging promises to be a highly exact tool for the characterisation of incidentally discovered benign liver lesions.