Researchers at the University of Illinois at Chicago also found that  patients with blockage of the blood vessels that supply blood to the back of the brain - a condition known as vertebrobasilar disease, or VBD - are at risk of having a stroke or temporary symptoms of a stroke known as transient ischemic attack (TIA).
    
These posterior-circulation strokes account for 30 per cent to 40 per cent of all ischemic strokes.     

The risk of a repeat stroke associated with VBD may be tied to several factors, including the degree to which the blockage reduces the blood flow to the brain, researchers said.
    
Patients with VBD can have blockage ranging from partial to complete, which affects blood flow accordingly. Some patients with VBD can also have normal blood flow to the back of the brain.
    
A six-year, multi-centre trial sought to identify patients with VBD and low blood flow to see if they had a higher risk of recurrent stroke than those with normal blood flow to the back of the brain.
    
A quarter of the enrolled patients were identified as having low posterior blood flow.
    
"We found that patients with low blood flow had a 22 percent risk of recurrent stroke in the first 12 months, versus a 4 percent risk for patients whose blood flow was not low," said Dr Sepideh Amin-Hanjani, professor of neurological surgery at the UIC College of Medicine and principal investigator on the study.
    
At 24 months, the risk for patients with low blood flow was up to 30 percent versus 13 percent for other patients.
    
NOVA technology, a computer-based system used to visualize brain anatomy and quantify blood flow developed at UIC by Dr Fady Charbel, professor and head of neurological surgery, made it possible to easily identify patients with reduced posterior blood flow using standard MRI.
    
With help from the UIC Office of Technology Management, NOVA was transferred to a newly formed company, VasSol, where the technology was further developed into a product with an improved user interface, adding functionality and applicability.

Latest News from Lifestyle News Desk