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Cerebral arteriovenous malformations (AVMs) present unique challenges to cerebrovascular specialists. Management of these lesions begins with assessing their natural history. Intervention with the goal of complete obliteration requires some component of microsurgical techniques or radiosurgery. Clinicians must weigh observation and acceptance of the natural history of these lesions versus intervention on a case-by-case basis. Microsurgical resection and radiosurgery are both well-validated tools used in selectively treating cerebral AVMs. This manuscript offers a general review of the management of cerebral AVMs with multimodality treatment recommendations.

Cerebral arteriovenous malformations (AVMs) are complex high-flow lesions that can result in devastating neurological injury when they hemorrhage. Embolization is a critical component in the management of many patients with cerebral AVMs. Embolization may be used as an independent curative therapy or more commonly in an adjuvant fashion prior to either micro- or radiosurgery. Although the treatment-related morbidity and mortality for AVMs—including that due to microsurgery, embolization, and radiosurgery—can be substantial, its natural history offers little solace. Fortunately, care by a multidisciplinary team experienced in the comprehensive management of AVMs can offer excellent results in most cases.

Neurovascular disorders, including brain aneurysms, arteriovenous malformations (AVMs), carotid artery disease, and intracranial atherosclerotic disease, take a huge health and economic toll on U.S. citizens and can lead to a host of neurological problems ranging from stroke and subarachnoid hemorrhage to disability and death. According to the Brain Aneurysm Foundation, cerebral aneurysms affect an estimated 6 million Americans and are responsible for close to half a million deaths worldwide each year, with half the victims age 50 and younger. 1 A 2004 study showed that survivors of brain aneurysm rupture and their caretakers lost roughly $138 million in combined wages in a single year. 1 Of the roughly 30,000 cases of aneurysmal subarachnoid hemorrhage that occur annually, about 60% result in disability or death. Close to 1 million strokes occur in the United States each year, with 10% to 15% attributed to intracranial atherosclerotic disease. Despite these devastating effects, progress has been made in the management of neurovascular diseases, and the field has undergone significant advances in the last decade due to the explosion of innovation in endovascular and microsurgical devices and treatments. This is particularly true for the treatment of cerebral aneurysms, especially after the landmark 2005 ISAT trial validating endovascular therapy as a mode of treatment for these types of lesions. 2 Since then, endovascular therapy has evolved from simple coiling to balloon- and stentassisted coiling and now flow diversion. These have all given surgeons and patients a broader range of options for treating aneurysms with new minimally invasive techniques. With flow diversion, the need for treating aneurysms with complex bypasses has dropped significantly although it remains important in a limited number of patients. Flow diversion uses a low-porosity stent placed in a parent artery across the aneurysm neck to slow blood flow and promote thrombosis, thereby excluding the aneurysm from circulation while preserving flow through the parent vessel. Early results have been promising for large proximal internal carotid aneurysms although early results for posterior circulation aneurysms have not been as favorable. 3

You have much to anticipate in your upcoming professional career with the likes of genomic medicine, regenerative medicine, and nanotechnology in the offing. I would like to be a fly on the wall 40 or 50 years into your careers to see if the extraordinary advances in medicine made in the last half-century are replicated. My guess is they will be even more extraordinary. To give you some perspective from my experience, I will share with you some aspects of medicine that I encountered at a similar stage as yours in my training. I graduated from Northwestern Medical School in 1953 at the age of 27. That occasion was further highlighted by my marriage to Barbara, who has survived living with a physician who for many of the past 61 years was more often than not away from home. We moved to Philadelphia so I could enter a 1-year rotating internship at the Philadelphia General Hospital, which was similar to The Houston Ben Taub Hospital. The Philadelphia General Hospital, affectionately called “old Blockley” by those who served there, no longer exists, nor do general rotating internships. The latter have been replaced by a “transitional year” for those physicians entering a nonmedical specialty. My marriage nearly floundered in the first month as my initial rotation was on a general surgical service. For each month, I was allowed one Wednesday afternoon and one Sunday off. Contrast that to the working hours trainees must adhere to today. As so often happened then for young physicians, I followed one of my role models, Dr. Thomas M. Durant, to Temple Medical School, where he was to become chairman of the Department of Medicine and also president of the American College of Physicians. The faculty at Temple Medical School Hospital was small and equally distributed between private practice physicians and full-time medical school physicians, all of whom were superb teachers. Penicillin, as a cure for streptococcal infections and a prevention for rheumatic fever, was well known, but there were literally hundreds of patients with rheumatic heart disease. At that time, there was a rheumatic heart disease hospital in Philadelphia to help care for them. In the 46 years since I’ve been in Houston, I may have seen one case of acute rheumatic fever from Louisiana and scattered cases of rheumatic heart disease from mostly south of the border. I spent 3 months at a tuberculosis sanatorium because tuberculosis was still very prominent. There I became proficient in producing pneumothorax and pneumoperitoneum as a form of treatment. Tuberculosis pericarditis was the most common form of pericarditis. My tuberculin skin test became positive when I was there. The most attractive part of that rotation was the monthly salary of $150 compared to the $50 I was paid at Temple. Remember, this was 60 years ago. Hypertension was treated medically with the rice diet and Smithwick splanchnicectomy (thoracic lumbar sympathectomy) operations, of which there were more than one.1 We became experts in physical diagnosis, because I knew that when we took the internal medicine board examination, the most common cause for failure was missing some significant physical finding. Examinations in those days were oral, and gamesmanship played a large role. My examination took place at King’s County Hospital in Brooklyn, and my examiner, well known for being a very tough examiner, entered the room where I was waiting and called my name, “Mr. Winters.” I learned that day not to take umbrage when being put down. As it turned out, the examiner and I hit it off right from the start, and I easily passed. I earned a Master’s degree in Medical Science during my residency, investigating new oral diabetic drugs that had just become available for study. At the end of my medical residency, I stayed on at Temple for 1 year as their first cardiology fellow. A year doesn’t sound like much in today’s timeframe, but at the time there was very little to learn. Electrocardiography, fluoroscopy, and chest X-rays were high on the list. A German physician, Hugo Roesler, was an expert in cardiac fluoroscopy and took pride in demonstrating his expertise. We spent hours perfecting our physical examination technique. Ballistocardiography became popular. And when I took my cardiology board examination in 1970, I was offered the option of interpreting electrocardiograms or ballistocardiograms. A myocardial infarction was treated by 6 weeks in bed, and the patient was not permitted to feed himself/herself the first week or two. Drugs available at the time included digitalis, morphine, nitroglycerin, oxygen, barbiturates, and an injectable form of mercuhydrin. There were no coronary care units; that concept came much later. Dr. George Burch at Tulane Medical School treated dilated cardiomyopathy with a year of bed rest. Among those who survived, a few actually improved. Patients with rheumatic heart disease and intractable peripheral edema frequently encountered “Southey tubes”—a small metal tube placed in the flesh of the lower extremities to drain fluid...a E D I T O R I A L

A 25-year-old patient with a 1p36 gene deletion was referred to cardiac magnetic resonance (CMR) imaging for evaluation of left ventricular noncompaction cardiomyopathy (LVNC). She had a recent history of palpitations that were not associated with chest pain or syncope. Electrocardiogram showed left ventricular hypertrophy with a strain pattern (Figure 1 H). Holter monitor showed only rare premature ventricular contractions. CMR showed prominent left ventricular trabeculation (Figure 1 A-E). The end diastolic compacted myocardium to noncompacted myocardium ratio met the CMR diagnostic criteria of > 2.3 for M U S E U M O F T M H M U L T I M O D A L I T Y I M A G I N G C E N T E R

Cerebral aneurysms are an important health issue in the United States, and the mortality rate following aneurysm rupture, or SAH, remains high. The treatment of these aneurysms uses endovascular options which include coil placement, stent assistant coiling and, recently, flow diversion. However, microsurgical clipping remains an option in those aneurysms not suited for endovascular therapy. These are often the more complicated aneurysms such as in large, giant aneurysms or deep-seated aneurysms. Circumferential visualization of the aneurysm, parent vessels, branches, perforators, and other neurovascular structures is important to prevent residual aneurysms or strokes from vessel or perforator occlusion. Decompression of the aneurysm sac is often required and we believe that adenosine-induced transient asystole should be an important option for clipping of complex cerebral aneurysms.

The worldwide prevalence of intracranial aneurysms is estimated to be between 5% and 10%, with some demographic variance. Subarachnoid hemorrhage secondary to ruptured intracranial aneurysm results in devastating neurological outcomes, leaving the majority of victims dead or disabled. Surgical clipping of intracranial aneurysms remained the definitive mode of treatment until Guglielmi detachable coils were introduced in the 1990s. This revolutionary innovation led to the recognition of neurointervention/neuroendovascular surgery as a bona fide option for intracranial aneurysms. Constant evolution of endovascular devices and techniques supported by several prospective randomized trials has catapulted the endovascular treatment of intracranial aneurysms to its current status as the preferred treatment modality for most ruptured and unruptured intracranial aneurysms. We are slowly transitioning from the era of coils to the era of flow diverters. Flow-diversion technology and techniques have revolutionized the treatment of wide-necked, giant, and fusiform aneurysms, where the results of microsurgery or conventional neuroendovascular strategies have traditionally been dismal. Although the Pipeline™ Embolization Device (ev3-Covidien, Irvine, CA) is the only flow-diversion device approved by the Food and Drug Administration for use in the United States, others are commercially available in Europe and South America, including the Silk (Balt Extrusion, Montmorency, France), Flow-Redirection Endoluminal Device (FRED; MicroVention, Tustin, CA), Surpass (Stryker, Kalamazoo, MI), and p64 (Phenox, Bochum, Germany). Improvements in technology and operator experience and the encouraging results of clinical trials have led to broader acceptance for the use of these devices in cerebral aneurysm management. Continued innovation and refinement of endovascular devices and techniques will inevitably improve technical success rates, reduce procedure-related complications, and broaden the endovascular therapeutic spectrum for varied aneurysm morphology.

Intracranial atherosclerotic disease is a significant cause of stroke in the United States. Much like coronary atherosclerosis, this disease leads to arterial stenosis secondary to the buildup of lipid-based plaques in intracranial vessels. Ischemic stroke may occur following thromboembolic events near the site of stenosis or from watershed ischemia secondary to cerebral hypoperfusion. While this disease has been treated with intracranial angioplasty and stenting and cerebrovascular bypass surgery, the current literature supports aggressive medical management with dual antiplatelet therapy, treatment of comorbidities such as hypertension, diabetes, and hyperlipidemia, and lifestyle modification. Intracranial angioplasty and stenting is reserved for cases of medical failure.