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Question:
I was wondering what happens to the brain/body of a person who suffers from a stroke? What is involved in the recovery/rehabilitation of a person who has suffered a stroke on both sides of their body? Do they have a full chance of recovery?



Replies:
A stroke occurs when an artery in the brain is suddenly blocked. Oxygenated blood flow downstream from the block stops, and the cells that need that oxygen to live start dying. Once neurons die, they are dead for good, and they are not replaced.

Hence, the effect of a stroke is to kill brain tissue. How much brain tissue is killed depends on where the block occurs and how long it lasts, if it doesn't last too long, or some kind of intervention shortens its duration.

The practical effects of a stroke depend, first, on an interesting fact about cell death. It turns out that when cells die, they release chemicals that damage nearby healthy cells. Sometimes this secondary damage is not permanent, and the damaged neurons can begin to function again. This is one source of the recovery after a stroke.

It is also the case that some areas of the brain are less used than others, and strokes there do not cause significant loss of function. Other areas are more critical. And still others are important, but their loss may be compensated for, over time, by the assumption of their tasks by other areas of the brain. In these cases, also, recovery of function can be expected.

Since the dead brain tissue can never be regenerated, it seems impossible for anyone to FULLY recover from a stroke, but it might be that the initial loss of function is much greater than the final, permanent loss. Only someone familiar with the clinical case in question could give an informed answer.

Grayce



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