About a quarter of all strokes occur when blood flow is reduced or cut off in the smallest blood vessels deep in the brain because of a disorder called small vessel disease. Researchers have begun to suspect that a condition previously thought to be benign—intracranial arterial dolichoectasia, in which the brain's larger arteries are stretched and misshapen—may be linked to the development of small vessel disease. French neurologists tried to figure out how the two might be connected.

What the researchers wanted to know: How is intracranial arterial dolichoectasia related to stroke and small-vessel disease?

What they did: The researchers looked at magnetic resonance imaging (MRI) scans from 510 people who had suffered a stroke caused by a blockage in a blood vessel (as opposed to bleeding into the brain from a ruptured vessel). The patients were separated into two groups. One group, about 12 percent of the total, had been diagnosed with intracranial arterial dolichoectasia. The other group did not have the condition. Then a team of neurologists evaluated the damage to each patient's brain, especially in discrete pockets particularly susceptible to small-vessel strokes.

What they found: The patients with intracranial arterial dolichoectasia were two to three times more likely than those without it to have brain damage from small-vessel disease. These patients were also more likely to have loss of brain tissue. The researchers say they do not know if intracranial arterial dolichoectasia causes small-vessel disease in the brain, or if both conditions have a common cause, but a link is evident.

What it means to you: For now, the findings don't have much clinical meaning, but they are likely to change the way doctors look at small-vessel disease and stroke in the future. The research argues for further work on intracranial arterial dolichoectasia and its possible impact on the brain's vascular health.

Caveats: Strangely, and with no explanation, participants were included in the study only if both of their parents were identified as of "white origin," so the results might not apply to other populations.

Find out more: Health and Age, a health information website, has a good description of small vessel disease.

For information on stroke, go to the National Institute of Neurological Disorders and Stroke.

Read the article: Pico, F. et al. "Intracranial Arterial Dolichoectasia and Small-Vessel Disease in Stroke Patients." Annals of Neurology. Published online Feb. 28, 2005, DOI: 10.1002/ana.20423