Brief Answer:
Read below.

Detailed Answer:
I read your question carefully and I understand your concern.

I guess this phrase was used in a MRI imaging report. It refers to a process which happens in all of us, in some earlier then others, it is part of aging. It means that the some of smallest, tiniest of the blood vessels are occluded, blocked. That happens due to the changes they undergo over the years (like all organs after all), with their walls becoming thicker and their diameter smaller.
As a result there is lack of blood flow to the brain cells they supply and they are damaged. In isolation they do not cause any symptoms, as I said these are tiny vessels, supplying tiny areas which individually we can do without. Only if the changes are advanced, widespread, of course the cell loss adds up and may lead to reduced functioning of the brain. However when mild such as in your case they shouldn't cause any symptom, they are not associated with headaches.

There is no specific treatment for it, but to control factors which can speed up this process such as high blood pressure, diabetes, smoking, high cholesterol etc. Other then managing these factors there is not much to be done, as you've been told it is part of aging and represents no reason for panic at your age, mild changes are common.

I remain at your disposal for other questions.

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