Acute subarachnoid hemorrhage. An unusual clinical presentation of cerebral venous sinus thrombosis.

Ruptured cerebral aneurysm is the most common cause of spontaneous subarachnoid hemorrhage (SAH). Rarely cerebral venous sinus thrombosis (CVST) may present initially as acute SAH, and clinically mimics aneurysmal bleed. We report 2 cases of CVST who presented with severe headache associated with neck pain and focal seizures. Non-contrast brain CT showed SAH, involving the sulci of the convexity of hemisphere (cSAH) without involving the basal cisterns. Both patients received treatment with anticoagulants and improved. Awareness of this unusual presentation of CVST is important for early diagnosis and treatment. The purpose of this paper is to emphasize the inclusion of vascular neuroimaging like MRI with venography or CT venography in the diagnostic workup of SAH, especially in a patient with strong clinical suspicion of CVST or in a patient where neuroimaging showed cSAH.