Endovascular Approach to Brain Aneurysm Treatment

RICHARD P. KLUCZNIK, M.D., Director, Brain Aneurysm Center, Methodist Hospital Neurological Institute

BY RICHARD P. KLUCZNIK, M.D., Director, Brain Aneurysm Center, Methodist Hospital Neurological Institute, Clinical Associate Professor, Weill Medical College, Cornell University

Chances are that many people have had the misfortune of experiencing a headache at some point in their life. Typically, relief is found within hours through the use of medication. In some cases, a headache that is persistent and that is often described as “the worst headache in my life” can be the symptom of something far more serious: a cerebral aneurysm.

Caused by a weak or thin spot on a blood vessel that balloons as it fills with blood, cerebral aneurysms can occur anywhere in the brain and, if ruptured, will cause blood to spill into surrounding tissues. Aneurysms can occur in anyone, at any age but are more common in adults than in children and are slightly more common in women than in men. Smoking, family history, diabetes and high blood pressure are all risk factors.

While a sudden and severe headache is the most common symptom of a ruptured aneurysm, other symptoms may include double vision, nausea, vomiting, stiff neck and/or loss of consciousness. It is important to note that most cerebral aneurysms do not show symptoms until they either become very large or burst. Ruptured aneurysms occur in about 10 of every 100,000 persons per year (roughly 27,000 patients per year in the U.S.) and of those affected, estimates show that 40% do not survive the first 24 hours. Early diagnosis is key for survival.

Traditionally, cerebral aneurysms were treated exclusively through a surgical procedure commonly referred to as “clipping”. During this procedure, an incision is made in the skull, the brain is retracted and a small “clip” similar to a clothespin is applied to the aneurysm. Today, physicians have an alternative for the treatment of particular aneurysms that allows for a faster recovery period and shorter hospital stay.

Endovascular embolization is a minimally invasive surgical procedure that involves making a small incision over the femoral artery and using the body’s own arteries as a conduit to approach the aneurysm internally. Due to advances in radiological imaging, 3- dimensional pictures of the aneurysm allow precise movement of the guide wire and microcatheters as they enter the aneurysmal sac. Once in the sac, small platinum coils are detached to form a “ball of yarn” in the aneurysm. These coils block the aneurysm from blood flow thereby destroying it from the inside.

As with any surgical procedure, there are risks involved which include damage to blood vessels, stroke or rupture (if the aneurysm is unruptured at the start of the procedure) but there is less than a 5% chance of any of these occurring.

Once the procedure is complete, the patient will typically spend 1-2 nights in the hospital before being released. Follow-up angiograms are performed at six months, 18 months and 3 years after the original treatment to insure that there is no regrowth of the aneurysm. Though physicians have used platinum coils for years in the treatment of aneurysms, the latest trend is in the use of bioactive coils that not only strengthen the aneurysm as if placing scaffolding inside a bubble, but also employ a special coating that helps promote the bodies own healing. Studies are still ongoing, but certain bioactive coils are demonstrating a lower incidence of re-growth of some aneurysms and, in the future, may offer patients a more permanent cure.

In addition to researching new devices such as flow diverters that will divert the flow of blood away from the aneurysm and new “slinky” type stents that provide more flexibility than those currently used, scientists are also collaborating with physicians to study the blood flow in cerebral aneurysms. By doing so, hopes are that one day physicians will be able to predict which aneurysms are more likely to rupture.

Using computer modeling and flow dynamics, scientists are able to study the pattern of blood flow in the vessels as well as the entrance into the aneurysms and aneurysmal sac. This combination can provide a thumbprint of sites in the aneurysm that are under greater stress and thus more likely to rupture. Physicians are hopeful that this information will enable them to custom design treatment techniques for each particular aneurysm.

Tremendous advances have been made in the treatment of cerebral aneurysms over the past 15 years. The survival rate has markedly improved in aneurysms that have ruptured and those aneurysms once deemed “untreatable” are now a thing of the past.

To help further research and treatment of cerebral aneurysms, the Houston Astros are teaming up with the Joe Niekro Foundation to host “The Knuckle Ball - A Pitch For Life” on Sept. 22 at Minute Maid Park. The black-tie gala will help raise funds for brain aneurysm research at The Methodist Hospital’s Neurological Institute. To learn more about “The Knuckle Ball”, go to Here or call 832.667.5856.