Brief Answer:
does not increase risk of stroke or dementia

Detailed Answer:
Hello and thank you for your question.
Subdural hemorrhages are fairly common after head trauma. As long as they are small they usually resolve on their own. They do not increase the risk for stroke or dementia.
You may have some memory problems for a short time but that usually is caused by the head trauma and unless you have repeated head traumas it resolves in a few months.
If the subdural is large it may need to be drained.
If yours is enlarging you would have headaches and perhaps other symptoms depending upon where it is located.
If it is small and stays that way it will go away in time.
It does not sound like you have anything to worry about if it is small.
I wish you the best,
Dr. Robinson

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