Meninges

The meninges (singular meninx) aresystemmembranes that containbrain. It consiststhree layers,dura mater,arachnoid, andpia mater.

The pia or pia mater isvery delicate membrane. Itclosest tobrainattached thereto.

The middle element ofmeninges isarachnoid.

The dura materclosest toskull.

The subarachnoid space isspace that normally exists betweenarachnoid andpia.

Normally,dura materattached toskull,arachnoidattached todura mater, andpia materattached tobrain. Whendura mater andarachnoid separate through injury or illness,space between them issubdural space.

A subdurmal hematoma is, therefore,separation ofarachnoid fromdura mater. The small veins that connectdura mater andarachnoidtorn,blood can leak into this area.