Neuroscience News Spring 2012

Vol. 3, No. 1

n

Spring 2012

Two years ago, the results of a large NIH-funded research trial showed that stenting is equal to surgery for treatment of carotid artery stenosis. In this issue of Neuroscience News, Christopher Nichols, MD, an interventional neurologist in Littleton, Colo., presents the conclusions of that trial and helps referring physicians better understand the available options.

IN SI D E 2 C arotid artery stenosis: risk factors and diagnosis

4 F amily history plays important role in aneurysms

5 Briefs :: C loud-based stroke care :: U sing deep brain stimulation to treat Tourette’s Syndrome

6 Meet our physicians

Stenting offers viable option for treating carotid artery stenosis

By Christopher W. Nichols, MD, Endovascular Surgical Neuroradiology and Vascular Neurology South Denver Neurosurgery For the past decade, carotid artery stenting has been reserved for use with patients with carotid artery stenosis who were at high-risk for experiencing negative outcomes with surgical intervention. Although a large NIH-funded trial two years ago found that stenting is equal to surgery and should be considered for all patients, the use of stenting has remained relatively low in Colorado mainly due to the lack of specialists available to perform this procedure and low awareness among referring physicians of the trial conclusions. �� continued on Page 2

Treating medically intractable posterior nose bleeds with non-surgical embolization

Photo: NOSE: ©iStockphoto.com/ anneleven

By Christopher W. Nichols, MD An estimated 10% of adults experience nose bleeds (epistaxis) requiring medical attention.

About 5% of these bleeds occur posteriorly, which carries a higher risk of dangerous, potentially fatal bleeding.

Of those most severely affected, many will have bleeding as a result of taking blood thinners, or having poorly controlled or undiagnosed hypertension. (In children, the number one cause of bleeding remains the index finger of the dominant hand.) Rarely, severe nosebleeds can be the result of a hereditary disorder such as hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu disease), a hereditary clotting disorder, a nasal neoplasm, or an aneurysm or arteriovenous fistula.

Bleeding in the anterior portion of the nose is generally managed medically with oxymetazoline (Afrin®), electrical or chemical cautery, nasal packing, balloon catheters, or thrombogenic foams or gels. �� continued on Page 3

Carotid artery stenosis from page 1 Patients with carotid artery stenosis—even with no obvious symptoms—are 50% more likely to experience an ischemic stroke or myocardial infarction and 80% more likely to die from a vascular event . (Goessens BMB, Visseren FLJ, et al; 2007) The condition is believed to cause more than 10% of all strokes. (Sacco RL, Ellenberg JH; 1989) These patients have traditionally been treated with carotid endarterectomy (CEA) to prevent vascular events, with several randomized controlled trials demonstrating good outcomes.

(North American Symptomatic Carotid Endarterectomy Trial Collaborators; 1991; Barnett HJ, Taylor DW, 1998; Minn AH, Kayton M, et al, 2004; Halliday A, Mansfield A, et al, 2004;Mayberg

MR, Wilson SE et al, 1991) However, in recent years the use of carotid artery stenting (CAS) has evolved as an alternative. CAS is particularly alluring given:  performed without general anesthesia  does not require an incision  fewer cardiovascular complications  does not carry a risk of cranial nerve palsy (Lanzino G, Rabinstein AA, et al, 2009)

CREST Trial Results

In 2010, the results of a National Institutes of Health-sponsored clinical trial comparing the two procedures were released (stent system manufacturer Abbott also contributed to the funding).

The Carotid Revascularization Endarterectomy versus Stenting

Trial, commonly known as CREST, was the largest prospective, randomized, multicenter clinical trial of endarterectomy versus stenting, enrolling 2,502 patients from 117 US and Canadian centers.

The study, published in the New England Journal of Medicine, found that after a median follow-up period of 2.5 years, the overall safety and efficacy of both procedures were largely equal for both men and

Carotid artery stenosis: risk factors and diagnosis

Photo courtesy of Photo Researchers Inc.

Carotid artery stenosis (CAS) is a manifestation of atherosclerosis in the internal carotid artery. Risk factors mimic those for coronary atherosclerosis, including:  Male  Age over 50  High total cholesterol and low high density lipid cholesterol  High levels of fibrinogen  High systolic blood pressure  Smoking  History of cerebrovascular disease, coronary heart disease, and/or peripheral artery disease. (Mathiesen EB, Joakimsen O, Bønaa KH, 2001)

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Diagnosis: Patients with asymptomatic CAS are typically identified either by listening for a carotid bruit (a sound resulting from turbulent blood flow in the carotid artery) during a physical examination or, in those with significant risk factors, noninvasive imaging such as carotid duplex ultrasonography, magnetic resonance angiography (MRA), and computed tomographic angiography (CTA). (McCaron MO, Goldstein LB, et al, 2012)

Neuroscience News | Spring 2012

Referrals: Patients with CAS should be referred for evaluation, and a treatment plan should include unbiased consideration of both stenting and surgery. We recommend discussion with both a vascular surgeon and with a physician specializing in carotid stenting. In truth, both procedures are likely to be viable options for treating symptomatic and asymptomatic stenoses.

In general, patients who may benefit from stenting are: high risk surgical candidates including those with prior neck irradiation or surgery, severe heart disease, or lung disease, or with lesions that are inaccessible by surgical approaches  candidates with stenosis secondary to other conditions such as fibromuscular dysplasia, arteritis, or dissection  those desiring a minimally invasive approach 

Patients who may benefit from surgery over stenting are: those with very tortuous anatomy  those with heavily calcified stenoses or those with luminal thrombus  patients with known coagulopathies or poor renal function, which makes stent thrombosis or contrast nephropathy more likely 

Photo courtesy of Photo Researchers Inc.

women and for patients who had previously suffered a stroke and those who had not. (Brott TG, Hobson RW, et al, 2010) Investigators did find a difference in the number of heart attacks and strokes following the initial procedure:  Heart attacks were more common in patients who had received surgery — 2.3 percent compared to 1.1 percent in patients who received stenting.  Strokes were more common in the patients who had received stenting— 4.1 percent compared to 2.3 percent in surgical patients.

Age also made a difference. Patients younger than 69 fared better with stenting, with results improving as patients got younger. For patients over age 70, surgery was slightly more beneficial than stenting. This finding may be related to the ease in which vascular access is obtained in patients of younger age.

In summary: Stenting shows equivalency to surgery for treating cervical carotid stenosis, but each procedure carries unique risks that need to be considered on a case-bycase basis. The CREST trial provided us with important risk/benefit for information that we can apply to choose the best carotid procedure based on each individual patient’s unique health history.

References: Barnett HJ, Taylor DW, Eliasziw M, et al. (1998). Benefit of carotid endarterectomy in patients with symptomatic moderate or severe stenosis. North American Symptomatic Carotid Endarterectomy Trial Collaborators. New England Journal of Medicine. 339(20):14151425.

Brott TG, Hobson RW, Howard G. (2010). Stenting versus Endarterectomy for Treatment of Carotid-Artery Stenosis. New England Journal of Medicine. 363(1):11-23.

Goessens BMB, Visseren FLJ, Kappelle LJ, et al. (2007).

Asymptomatic Carotid Artery Stenosis and the Risk of New Vascular Events in Patients With Manifest Arterial Disease: The SMART Study. Stroke.

38(5):1470-1475.

Halliday A, Mansfield A, Marro J, et al. (2004). Prevention of disabling and fatal strokes by successful carotid endarterectomy in patients without recent neurological symptoms: randomised controlled trial. Lancet.

363(9420):1491-1502.

Lanzino G, Rabinstein AA, Brown RD, Jr. Treatment of carotid artery stenosis: medical therapy, surgery, or stenting? Mayo Clinic Proceedings.

84(4):362-387.

Mathiesen EB, Joakimsen O, Bønaa KH. (2001). Prevalence of and risk factors associated with carotid artery stenosis: the Tromsø Study.

Cerebrovascular Disease. 12(1):44-51.

Mayberg MR, Wilson SE, Yatsu F, et al. (1991). Carotid endarterectomy and prevention of cerebral ischemia in symptomatic carotid stenosis.

Veterans Affairs Cooperative Studies Program 309 Trialist Group. Journal of the American Medical Association.

266(23):3289-3294.

McCaroon MO, Goldstein LB, Matchar DB. (2012). Screening for asymptomatic carotid artery stenosis.

UpToDate. Last updated: May 19, 2011.

Minn AH, Kayton M, Lorang D, et al.

(2004). Insulinomas and expression of an insulin splice variant. Lancet.

363(9406):363-367.

North American Symptomatic Carotid Endarterectomy Trial Collaborators.

(1991). Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. New England Journal of Medicine. 325(7):445-453.

Sacco RL, Ellenberg JH, Mohr JP, et al. (1989). Infarcts of undetermined cause: the NINCDS Stroke Data Bank.

Annals of Neurology. 25(4):382-390.

Nose Bleeds

from page 1

Posterior bleeding, due to difficulty in accessing the posterior nasopharynx with the above treatments, typically requires hospitalization and careful hemodynamic and cardiac monitoring. Initial treatment consists of attempts to mechanically tamponade the site of bleeding with double balloon catheters or a Foley catheter. If those fail, the next step is surgical or endovascular embolization.

Surgical options include endoscopic sphenopalatine (cauterization) or anterior ethmoid artery ligation.

Endovascular options not requiring surgical treatment focus on a minimally invasive catheter-based technique known as transarterial particle embolization. In the latter procedure, arterial supply to the nasopharynx is blocked using embolization particles, thus stopping bleeding.

Angiographic embolization

In transarterial particle embolization, patients are evaluated with an angiogram of the internal and external carotid artery to identify any abnormalities that may be causing the bleeding. In about 70% of cases, we find that the bleeding is spontaneous in nature. Patients with idiopathic epistaxis, arteriovenous malformation, and, in some cases, heredity hemorrhagic telangiectasia, are good candidates for this procedure. (Willems PWA, Farb RI, Agid R, 2009) Using general or local anesthesia, a catheter is inserted into the femoral artery. Subselective catheterization with a microcatheter is accomplished by guiding a wire into the ipsilateral internal maximally artery (IMA). Polyvinyl alcohol (PVA) is then injected under fluoroscopic guidance into the vessels that supply blood to the nasal region, which clot and close. While bleeding may be localized to one side of the nose, it is not uncommon to embolize both internal maxillary arteries and the ipsilateral facial artery. Embolization of these additional arteries helps ensure a complete treatment and decreases the rate of recurrent bleeding.

The procedure has a success rate of between 93% and 100%, primarily in patients with idiopathic bleeding, though if early rebleeding occurs (within 72 hours to 33 days), the long-term success rate falls to 77% to 95%.

(Willems PWA, Farb RI, Agid R, 2009) This procedure requires a 1- to 2-day hospital stay, primarily for observation following treatment.

Complications are frequently mild and will most likely resolve spontaneously. They include headache and facial and/or jaw pain, swelling, and numbness. (Willems PWA, Farb RI, Agid R, 2009) As with all procedures, there is a small risk of more severe complications, and a thorough discussion of the procedure with the performing physician is important. Patients typically return to normal activities within 1-2 weeks.

References Alter H. (2011). Approach to the adult with epistaxis. UpToDate. http://www. uptodate.com/contents/approach-to-the-adult-with-epistaxis?source=search_ result&search=epistaxis&selectedTitle=1~150. Accessed January 29, 2012.

Willems PWA, Farb RI, Agid R. (2009). Endovascular Treatment of Epistaxis.

American Journal of Neuroradiology, 30:1637-45

Family history plays important role in aneurysms

Two percent of Americans have a cerebral aneurysm, which is a blood-filled bulge in a blood vessel in the brain.

By Christopher W. Nichols, MD Endovascular Surgical Neuroradiologist and Vascular Neurologist South Denver Neurosurgery An estimated 2.7 million people in the US—about 2% of the population—have at least one intracranial aneurysm, with 20% of them having more than one.

(Rinkel JE, et al, 1998) Most brain aneurysms are undiagnosed and, given the low risk of rupture, that’s generally OK. However, with a mortality rate of up to 50% if rupture occurs, it is important to identify individuals at higher risk not only for the aneurysm itself, but for a rupture. (Weibers DO, 1998; NIH) One important risk factor is family history, with about 20% of cerebral aneurysms having a genetic component. A person with two or more first-degree relatives diagnosed with an aneurysm is four times more likely to also have one. (Broderick JP et al, 2009; Ronkainen A, Hernesniemi J, et al, 1997) Other inherited conditions associated with aneurysms include Ehlers-Danlos IV, Marfan’s Syndrome, neurofibromatosis, fibromuscular dysplasia, and polycystic kidney disease.

To better identify genetic links to cerebral aneurysms, the National Institutes of Health has funded the Familial Intracranial Aneurysm (FIA) study. This international collaborative of neurologists and neurosurgeons is designed to identify genetic and other risk factors that may be involved in the development of intracranial aneurysms.

Enrollment is still ongoing for families with multiple affected family members as well as all intracranial aneurysm patients. (FIAstudy.org) References Broderick JP, Brown RD Jr, Sauerbeck L, et al. (2009). Greater rupture risk for familial as compared to sporadic unruptured intracranial aneurysms. Stroke.

40(6):1952-75 Familial Intracranial Aneurysm. Available at www.fiastsudy.org. Accessed January 31, 2012 National Institute of Neurological Disorders and Stroke. NINDS Cerebral Aneurysms Information Page. Last updated September 14, 2011. Available at: http://www.ninds.nih.gov/disorders/cerebral_aneurysm/cerebral_aneurysms.htm.

Accessed January 31, 2012 Rinkel, J.E., et al. (1998). Prevalence and risk of rupture of intracranial aneurysms: a systematic review. Stroke. 1998; 29:251-256 Ronkainen, A., Hernesniemi J., Puranen M., Niemitukia L., Vanninen R.L., Kuivaniemi H., et al. (1997). Familial intracranial aneurysms. Lancet. 349: 380-384 Wiebers, D.O. (1998). Unruptured intracranial aneurysms—risk of rupture and risks of surgical intervention. New England Journal of Medicine. 339:1725-33

Photo courtesy of Photo Researchers Inc.

Aneurysms:

J u s t t h e Fa c t s

Non-genetic risk factors:

> Smoking > Trauma > Atherosclerosis > Hypertension > Systemic infection, such as endocarditis > Age (between 30 and 60 years in women and after age 65 in men) Screening: Screening is generally not recommended for asymptomatic individuals. However, it is often worthwhile in patients with a known family history of aneurysm rupture or other high-risk inherited conditions.

Patients are generally screened with non-invasive imaging studies such as MRI or CT angiography, which are highly sensitive.

If an aneurysm is discovered, patients should be referred to a vascular neurologist or neurosurgeon specializing in treatment of cerebral aneurysms.

Treatment: Depends on the size, morphology, and location of an aneurysm, as well as other coexisting risk factors such as smoking and family history. Generally, aneurysms that are larger or in the posterior circulation are most likely to rupture. A family history of ruptured aneurysms and concomitant smoking may correlate highly with the risk of an aneurysm rupturing. If a decision is made to intervene, options include surgical clipping, endovascular coiling or embolization, and parent artery occlusion with or without surgical bypass. In our practice we have begun using one of the newest embolization devices, Onyx HD 500 liquid embolic agent. It functions as “glue,” hardening when exposed to blood. Onyx HD 500 is used in patients who cannot undergo treatment by traditional coil embolization or surgical clipping.

Christopher Nichols, MD, is the only neurologist specializing in interventional neuroradiology in Colorado. He is certified by the American Board of Psychiatry and Neurology. Dr. Nichols’ current research and clinical interests include: - long-term follow-up of patients undergoing angioplasty for symptomatic vasospasm - advances in angioplasty treatments for intracranial diseases, including vasospasm, intracranial artherosclerosis, and stroke Dr. Nichols completed his undergraduate degree at Yale University, and obtained his medical degree from Drexel University College of Medicine. He completed his medical internship and neurology residency at the University of Colorado Health Sciences Center. Dr. Nichols completed two fellowships at the University of Cincinnati, one in stroke and vascular neurology and a second in endovascular surgical neuroradiology.

SouthDenverNeurosurgery.org | Neuroscience News

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briefs

Cloud-based stroke care Rural patients get access to life-saving expertise Residents and visitors in the popular Durango and Four Corners areas of Colorado now have access to fast and potentially lifesaving stroke treatment through an advanced technology-based program with Littleton Adventist Hospital in Denver.

The program, called Telestroke, is a cloud-based (internet) system. High-speed network video conferencing and image-sharing technology connect Littleton Hospital neurologists to patients and staff in Mercy Regional Medical the emergency room Center, Durango of Mercy Regional Medical Center in Durango. Using this technology, a Littleton Hospital neurologist can perform a neurological examination and view computer tomography (CT) scans to evaluate

for intracranial hemorrhage or conditions that may mimic stroke in clinical presentation. The neurologist also can communicate real-time with the patient and Mercy emergency team.

“Telestroke brings immediate and effective care to patients who otherwise would not receive stroke care within the eight-hour window for advanced stroke intervention,” says Mihaela Alexander, MD, stroke and neurology medical director at Littleton Adventist Hospital.

According to the National Stroke Association, stroke is a leading cause of adult disability. One form of treatment is to administer a clot busting drug, called tissue plasminogen activator or tPA, that can greatly reduce the disability resulting from a stroke. This drug, however, must be administered within 4.5 hours of the onset of symptoms.

“Stroke does not discriminate.

You can’t be hesitant. You need

Littleton Adventist Hospital

expertise quickly,” says Paul Gibson, Mercy’s emergency services director. “Telestroke will enable the residents of Durango and surrounding communities to receive expert neurological care in the ‘golden hour’ when the need for precise diagnosis and immediate treatment can often make the difference between a lifelong disability and a return to normalcy.”

Littleton Hospital and Mercy are members of the Centura Health Stroke Network. Littleton is one of two acute certified stroke centers within the network that is comprehensive capable, meaning that advanced interventions can be performed to remove or dissolve the stroke-causing clot in the brain.

Using deep brain stimulation to treat Tourette’s Syndrome

By Mariel Szapiel, MD, Neurosurgeon :: South Denver Neurosurgery While Tourette’s Syndrome is most commonly identified by uncontrollable outbursts of foul language, this condition is first and foremost a neurological movement disorder marked by tics rather than tremors. As deep brain stimulation has proved increasingly effective for various movement disorders, including essential tremor and Parkinson’s disease, it has begun to be used with Tourette’s Syndrome as well with mixed results.

The procedure was first used on Tourette patients in 1999. Since then, at least 10 areas of the brain have been targeted for DBS, with varying effects. Most patients experience some benefit, with published long-term evaluations demonstrating that improvement is maintained over time. Side effects vary depending on the part of the brain targeted, but seem to include changes in sexual behavior, drowsiness and reduced energy, and mild speech difficulties.

Because this is still an emerging treatment, patient inclusion criteria are strict.

References Among other factors, patients must meet the following conditions to be considered as Ackermans, L., Temel Y., and Visser-Vandewalle, V. candidates: (2008). Deep brain stimulation  >25 years old in Tourette’s Syndrome.  Severe tic disorder with severe functional impairment (>35/50 YGTSS for 12 months) Neurotherapeutics. 5(2):339-44.  Failed conventional therapy from minimum three pharmacological classes Mink, J.W., Walkup J., et al.

(2006) Patient selection and  Compliant with psychological interventions We will be addressing DBS in Tourette’s patients more in-depth in future issues of Neuroscience News.

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Neuroscience News | Spring 2012

assessment recommendations for deep brain stimulation in Tourette syndrome. Movement Disorders. 21(11): 1831-1838.

About us

PRSRT STD U.S. Postage

South Denver Neurosurgery provides state-ofthe-art diagnostic and treatment programs for a wide range of brain and spinal disorders. We partner with our patients and their physician teams to make individualized decisions and treatment plans. Our physicians are some of the most experienced in the Rocky Mountain region, offering the latest, most up-to-date procedures and treatment options to patients.

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7780 S. Broadway, Suite 350 Littleton, CO 80122

Denver, CO Permit No. 1818

Physicians desiring a consult, please call: 303.734.8650.

Locations: Littleton Adventist Hospital Campus Arapahoe Medical Plaza III 7780 S. Broadway, Suite 350 Littleton, CO 80122 Porter Adventist Hospital Campus Harvard Park Medical Plaza 950 E. Harvard Ave., Suite 570 Denver, CO 80210 Castle Rock Adventist Health Campus 1189 S. Perry St., Suite 230 Castle Rock, CO 80104 Parker Adventist Health Campus Crown Point Healthcare Center New 9235 Crown Crest Blvd, Suite 130 Location Parker, CO 80138

South Denver Neurosurgery is operated by Centura Health Physician Group.

Centura Health complies with the Civil Rights Act of 1964 and Section 504 of the Rehabilitation Act of 1973, and no person shall be excluded from participation in, be denied benefits of, or otherwise be subjected to discrimination in the provision of any care or service on the grounds of race, religion, color, sex, national origin, sexual preference, ancestry, age, familial status, disability or handicap. Copyright © Centura Health, 2012

Meet our physicians

Ben Guiot, MD Neurosurgeon, boardcertified by the American Board of Neurological Surgeons and the Royal College of Physicians and Surgeons of Canada. Specializing in all aspects of spine care, including: :: Minimally invasive spine surgery :: Spinal deformity correction :: Reconstruction of complex spinal disorders

Christopher Nichols, MD Neurologist, specializing in stroke and vascular neurology and endovascular neurosurgery, including evaluation and treatment of: :: Brain aneurysms :: Arteriovenous malformations :: D ural arteriovenous fistulas :: A cute stroke and intracerebral hemorrhage :: C ervical and intracranial arterial disease :: C erebral vasculopathy :: C erebral venous thrombosis

J. Adair Prall, MD Neurosurgeon, specializing in: :: Trigeminal neuralgia :: Spinal disorders :: Neuro-oncology :: Minimally invasive and motion-preserving spine surgery :: Stereotactic radiosurgery (Gamma Knife® and CyberKnife®)

Mariel Szapiel, MD Neurosurgeon, specializing in neuromodulation for chronic diseases, including: :: Essential tremor :: Dystonia :: Parkinson’s disease :: Tourette’s syndrome :: Obsessive-compulsive disorder and other mood disorders :: C hronic intractable headaches

David VanSickle, MD, PhD Neurosurgeon, PhD in bioengineering, specializing in:

:: D eep brain stimulation (DBS) for Parkinson’s and essential tremor :: Epilepsy surgery :: Neuro-oncology :: Spinal cord stimulator implantation for pain :: Transsphenoidal surgery (pituitary surgery) :: Minimally invasive and motion-preserving spine surgery :: Stereotactic radiosurgery (Gamma Knife® and CyberKnife®)