A 35 year-old man presented with an acute, severe headache. His neurologic examination was non-focal.

Axial CT Scans without contrast: Looking closely, note the bright area in several sulci which signifies blood. Spontaneous subarachnoid hemorrhage is most often caused by a ruptured aneurysm.  They usually present with hemorrhage and signs of increased intracranial pressure.  Sometimes, a relatively minor bleed will occur before a massive bleed, known as a sentinel bleed. In this case, a subsequent angiogram showed a left middle cerebral artery aneurysm.

Revised 04/30/06.
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