A 46-year-old member asked:
what is the difference between arachnoid and sub arachnoid?
1 doctor answer • 2 doctors weighed in
Psychiatry 42 years experience
Brain membranes: There are 3 layers of coverings on the brain & spinal cord. The outermost is the dura mater; middle one is called "arachnoid, " and the innermost (lying directly on the brain & spinal cord) is the pia mater. "subarachnoid" means in the space beneath the arachnoid membrane, yet above the pia mater. There can be bleeding in the subarachnoid space, due to damaged blood vessels or aneurysms.
5108 viewsReviewed >2 years ago
Last updated Sep 28, 2016
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