Mini-strokes create lasting damage to the brain

Washington: A new research has suggested transient ischemic attack (TIA), also known as a mini-stroke, creates lasting damage to the brain.

The stroke research team, led by Lara Boyd, of the Brain Research Centre at Vancouver Coastal Health and the University of British Columbia, studied 13 patients from the Stroke Prevention Clinic at Vancouver General Hospital and compared them against 13 healthy study participants.

The patients were studied within 14-30 days of their episode, and showed no impairment through clinical evaluation or standard imaging (CT or MRI).

Participants then underwent a unique brain mapping procedure using transcranial magnetic stimulation (TMS) with profound results.

"The brain mapping capabilities of the TMS showed us that TIA is actually causing damage to the brain that lasts much longer than we previously thought it did. In fact, we are not sure if the brain ever recovers," said Boyd.

In the TIA group, brain cells on the affected side of the brain showed changes in their excitability - making it harder for both excitatory and inhibitory neurons to respond as compared to the undamaged side and to a group of people with healthy brains.

These changes are very concerning to the researchers as they show that TIA is likely not a transient event.

"We know that TIA is a warning sign of future stroke. We treat every TIA as though it will result in a stroke, but not every person goes on to have a stroke. By refining this brain mapping technique, our hope is to identify who is most at risk, and direct treatment more appropriately," said Philip Teal, co-author of the study.

The findings were reported in Stroke, the journal of the American Heart Association.