Another case of “nonaneurysmal subarachnoid hemorrhage” — until there is an aneurysm
First angio negative
DYNA CT follow up negative
Third angio — who would do one? And under general anesthesia. Oblique view showing a small aneurysm (arrow) arising from upper basilar perforator
DYNA. Notice small caliber of vessel at ostium, followed by pseudoaneurysm. This is a classic dissecting aneurysm appearance
Learning point — as technology improves, and as we decide that looking for a cause is worthwhile, we might discover a few more of these in the “nonaneurysmal SAH” wastebasket.
Companion case here