What research is being done on cerebral aneurysm in United States?
The National Institute of Neurological Disorders and Stroke (NINDS) recently sponsored the International Study of Unruptured Intracranial Aneurysms, which included more than 4,000 patients at 61 sites in the United States, Canada, and Europe. The findings suggest that the risk of rupture for most very small aneurysms (less than 7 millimeters in size) is low.
NINDS scientists are studying the effects of an experimental drug in treating vasospasm that occurs following rupture of a cerebral aneurysm. The drug, developed at NIH, delivers nitric oxide to the arteries and has been shown to reverse and prevent brain artery spasm in animals.
Other scientists hope to improve diagnosis and prediction of cerebral vasospasm by developing antibodies to molecules known to cause vasospasm. These molecules can be detected in the cerebrospinal fluid of subarachnoid hemorrhage patients. An additional study will compare standard treatment for subarachnoid hemorrhage to standard treatment plus transluminal balloon angioplasty immediately after severe bleeding. Transluminal balloon angioplasty involves the insertion, via catheter, of a deflated balloon through the affected artery and into the clot. The balloon is inflated to widen the artery and restore blood flow (the deflated balloon and catheter are then withdrawn).
Researchers are building a new, noninvasive, high-resolution x-ray detector system that can be used to guide the placement of stents (small tube-like devices that keep blood vessels open) used to modify blood flow during treatment for brain aneurysms.
Scientists are investigating the use of intraoperative hypothermia during microclip surgery as a means to improve the rate of recovery of cognitive functions and to reduce early and postoperative complications and neurological damage. Other studies are investigating ways to improve or replace the coils used in endovascular embolization.
Cerebral Aneurysm statistics in United States
The true incidence of intracranial aneurysms is unknown but is estimated at 1-6% of the population (Wiebers, 2003). Published data vary according to the definition of what constitutes an aneurysm and whether the series is based on autopsy data or angiographic studies. In one series of patients undergoing coronary angiography, incidental intracranial aneurysms were found in 5.6% of cases, and another series found aneurysms in 1% of patients undergoing 4-vessel cerebral angiography for indications other than subarachnoid hemorrhage (SAH). Familial intracranial aneurysms have been reported (Schievink, 1997). Whether this represents a true increased incidence is unclear.
Aneurysms typically become symptomatic in people aged 40-60 years, with the peak incidence of SAH occurring in people aged 55-60 years (Greenberg, 2001). Intracranial aneurysms are uncommon in children and account for less than 2% of all cases. Aneurysms in the pediatric age group are often more posttraumatic or mycotic than degenerative and have a slight male predilection. Aneurysms found in children are also larger than those found in adults, averaging 17 mm in diameter. Aneurysms have shown a slightly more frequent in women than man.