Presentation
Sudden loss of consciousness.
Patient Data
Moderate volume of acute subarachnoid hemorrhage within the basal cisterns, bilateral sylvian fissures, and anterior interhemispheric fissure. There is higher volume in the right sylvian fissure compared to the left. The pattern suggests a ruptured aneurysm, most likely at the right MCA bifurcation. There is intraventricular extension of hemorrhage into the 4th ventricle and occipital horn of the left lateral ventricle with associated hydrocephalus with particular enlargement of the temporal horns of the lateral ventricles.
CT angiogram shows two right MCA bifurcation aneurysms, the larger of which is irregular suggestive of recent rupture. A tiny left MCA bifurcation aneurysm is also present.
24 hours later the patient has undergone right MCA aneurysm clipping and a left frontal EVD insertion with excellent decompression of the ventricles.
Case Discussion
Key teaching points for this case:
- pattern of SAH on non-contrast CT can help predict if and where an aneurysm is likely to be
- don't stop after finding one aneruysm on CT angiogram; there are often multiple
- hydrocephalus as a complication of SAH > urgent EVD placement required