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It's not (always) brain surgery


Tufts MC Physician’s Cutting Edge Research on Brain Aneurysm Rupture Risk Will Guide Treatment

The Brain Aneurysm Foundation reports that six million people in the United States – about two percent of the population – are living with a brain aneurysm, a weak spot in the brain’s artery wall. While most brain aneurysms will never cause a problem during a person’s lifetime, there are still 30,000 instances of aneurysm rupture in the U.S. every year. 

Ruptured brain aneurysms are fatal in about 40 percent of cases and more than 60 percent of those who survive suffer some level of permanent neurological damage. The good news is most aneurysms are treatable with either microsurgical clipping or minimally invasive coiling or stenting if recognized in time. But how do physicians know which aneurysms are likely to rupture and truly require an invasive and costly intervention? Tufts Medical Center is one of only a handful of centers in the world where investigators are conducting groundbreaking research to equip medical personnel with that critical information.

“It’s an ongoing challenge to find better ways to detect aneurysms and identify characteristics of an elevated risk of rupture,” said Chief of the Division of Cerebrovascular and Endovascular Neurosurgery Adel Malek, MD, PhD. “If physicians have the necessary information at their disposal to counsel patients on whether or not an aneurysm needs to be treated, we can save lives by avoiding unneeded surgeries and reduce health care costs by actively treating dangerous aneurysms, but not benign ones.”

Dr. Malek, who has been at the forefront of the study of the effect of mechanical forces on vascular cells for more than 25 years, is conducting groundbreaking studies to better understand the link between aneurysm features and blood flow characteristics and a predisposition to rupture. 

By employing state-of-the-art tools, including three-dimensional shape analysis imaging and computational fluid dynamics, a cutting edge engineering technique used in the automobile and aerospace industry, Dr. Malek is able to predict blood flow conditions inside an aneurysm and provide critical information about its risk of rupture. His group then uses statistical modeling to evaluate and compare a number of aneurysm shape criteria, including depth, height, width, shape, size and aspect ratio, and assess trends, patterns and difference between aneurysms likely to rupture and those less likely to do so.

“Many neurosurgeons focus solely on the size of the aneurysm to guide clinical decisions, but it’s really much more complex than that,” said Dr. Malek. “Size is limited as an indicator and in some cases, it may not be the most important marker.”

In general terms, the Malek lab has found that if the aneurysm has a smooth surface, a big neck and uninhibited blood flow in and out, it is less likely to rupture. If it has an irregular shape and surface, narrow neck and blood flow is slow and stagnant, it is more likely to have inflammation and thinning of the wall; those factors may contribute to weakening of the wall and eventual rupture.

Working in conjunction with Tufts University School of Engineering colleagues Eric Miller, PhD and Alex Lauric, PhD, Dr. Malek’s Cerebrovascular Hemodynamics Lab was recently issued a U.S. patent on a new method for aneurysm detection. His ultimate goal is to continue to improve and refine predictive modeling to the point where neurologists and neurosurgeons can incorporate a highly accurate metric into their everyday clinical practice. Dr. Malek hopes that physicians and surgeons will soon be able to tailor their care plan for each patient and each aneurysm on an individual basis, aggressively treating those patients at high risk for rupture and recommending against high-risk surgery for those not in imminent danger.