Non-aneurysmal subarachnoid hemorrhage in aplastic or twig-like middle cerebral artery: A case report and literature review.

Background: Aplastic or twig-like middle cerebral artery (Ap/T-MCA) is a rare vascular anomaly that can cause hemorrhagic and ischemic stroke. Ap/T-MCA can induce aneurysms due to the fragility of the vessel wall, consequently leading to subarachnoid hemorrhage. Herein, we report a case of Ap/T-MCA with subarachnoid hemorrhage without an aneurysm.

Methods: A 67-year-old man presented to our hospital with a sudden onset of headache. Computed tomography of the head revealed subarachnoid hemorrhage (SAH) in the left Sylvian fissure; however, no aneurysm was observed on digital subtraction angiography. Following conservative treatment, follow-up imaging showed no aneurysm or no recurrent stroke.

Conclusions: Non-aneurysmal SAH is a possible indication of vessel wall fragility in Ap/T-MCA; however, a standardized treatment strategy for this condition remains to be established.