Intraparenchymal supratentorial arachnoid cyst: a case report

Background Intracranial arachnoid cysts are collections of cerebrospinal fluid within the arachnoid membrane and subarachnoid space of the cisterns and major cerebral fissures that account for about 1% of all intracranial lesions. Expansion of the cyst and compression on surrounding structures may became symptomatic, which reflects its size and anatomic distribution. Case presentation Here, we present a very rare case of patient with supratentorial intraparenchymal arachnoid cyst placed in the left frontal lobe without any communication with the subarachnoid space and ventricle and presented with clinical symptoms. The patient underwent fenestration of the lesion and was clinically improved. Conclusions Although the etiology and the enlargement mechanism of arachnoid cysts remain unclear, both conservative and surgical treatments are optional. According to size, anatomical location, neuroimaging, and clinical symptoms, an arachnoid cyst should be included in the differential diagnosis of primary intracerebral cysts.