A Rare Triad of Lateral Rectus Palsy, Sylvain Fissure Bleed, and Bilateral SDH Shrouding a Benign Pathology

Arachnoid cysts are benign extra-cerebral congenital lesions that are thought to arise from the splitting of the arachnoid membrane. Although most arachnoid cysts remain static with advancing age, occasionally they can become symptomatic due to cyst enlargement or hemorrhage. Hemorrhage into the arachnoid cysts (intra-cystic hemorrhage) with or without associated subdural hematoma is of rare occurrence.

A 23-year-old male presented with a history of sudden onset severe headache while sleeping. The patient also noticed double vision, especially when looking towards the left side. Non-contrast computed tomography (NCCT) scan of the head showed left temporal pole hematoma with left Sylvian fissure bleed and bilateral fronto-temporoparietal (FTP) subacute SDH.

Every patient with incidentally detected AC, especially in the middle cranial fossa, should be counseled regarding the risk of possible complications including hemorrhage and regular follow-up.