Arachnoid cysts are developmental anomalies which are usually asymptomatic. There are va-rious opinions regarding the etiological factors. Intracystic hemorrhage after trauma is a well known complication of arachnoid cysts; however, spontaneous intracystic hemorrhage is rare. The presented case was admitted to our clinic following transient loss of consciousness and dysphasia, and a hematoma having the characteristics of a subacute subdural hematoma at the left temporal region was diagnosed. However, the hematoma was found to be an intracystic one during surgical intervention. This report presents a rare case of an arachnoid cyst complicated by spontaneous intracystic hemorrhage, demonstrating radiological and clinical features of the case.

Keywords: Arachnoid cyst, intracystic hematoma, subdural hematoma