Presentation
Presented with thunderclap headache on heavy lifting.
Patient Data
Age: 55 years
Gender: Male
From the case:
Perimesencephalic subarachnoid hemorrhage
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There is hyperdensity surrounding the midbrain and pons extending into the basal cisterns.
No other acute intracranial pathology.
CTA was performed (not shown) which was negative for aneurysms.
Case Discussion
Perimesencephalic subarachnoid hemorrhage is a rare cause of subarachnoid hemorrhage thought to be due to a venous bleed. When it has a normal angiogram, the prognosis is favorable.
However, this distribution can also be seen in vertebrobasilar aneurysm-related subarachnoid hemorrhage. If there is an aneurysm within the posterior circulation, the prognosis is less favorable.
In this case, CT and DSA Angiogram were normal.