Subarachnoid Hemorrhage Caused by Supratentorial Cerebral Cavernous Malformation: A Case Report.

Cavernous malformations (CMs) are acquired vascular abnormalities of the central nervous system that are typically asymptomatic. Clinically symptomatic lesions may present with seizures, intracerebral hemorrhage, or focal neurological deficits. Very rarely, CMs have been described as the cause of subarachnoid hemorrhage. We report a case of a previously healthy 58-year-old man who presented with acute onset of severe headache associated with vomiting. Head computed tomography (CT) scan showed subarachnoid hemorrhage with intraventricular extension. Subsequent CT angiography (CTA) and digital subtraction angiography (DSA) studies showed no evidence of vascular abnormalities. The patient was initially managed conservatively but later required neurosurgical and radiological interventions due to a complicated hospital course and worsening clinical condition. During surgery, an incidental mass was found in the temporal lobe, and subsequent histopathological examination confirmed the diagnosis of cavernoma, which was likely the underlying cause of the subarachnoid hemorrhage. This report highlights the importance of considering CMs in the differential diagnoses of subarachnoid hemorrhage, especially in the absence of informative results from CTA and DSA studies. Timely detection and management of CMs may positively impact the clinical outcome, leading to reduced morbidity and mortality rates.