Brief Answer:
Small vessels narrowing.

Detailed Answer:
Hello again.

I will try to explain you in patient talk about microangiopathy.

It is a condition that affects small blood vessels of the body, and where is evidence of brain vessels involvement is called cerebral microangiopathy.

Supratentorial is an anatomic term that refers to localisation.

Causes include high blood presure, age, high lipids, amyloid accumulation etc.

All these cause narrowing of small vessels affecting this way blood supply of that area.

If small ares of brain involved, there is no danger, if there is extension of microangiopathy, there is risk to develop stroke.

Hope i helped you.

If you have further questions, feel free to ask.

Take care.

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