Spontaneous intracystic hemorrhage of the arachnoid cyst: a case report and review of literature.

Arachnoid cysts represent benign cysts that occur in the cerebrospinal axis in relation to the arachnoid membrane and do not communicate with the ventricular system. We report a case of a years right handed lady, who presented to the emergency department with the complaints of headache and vomiting for one week CT scan showed extraaxial cystic lesion in the left fronto-parietal region. On the fifth day of admission, patient had sudden onset of severe headache associated with loss of consciousness for about 3-4 minutes with neck rigidity. A CT scan of head was repeated, which showed left fronto-parietal cystic lesion with intracystic bleed and SAH. Intraoperatively, there was intradural cystic lesion containing xanthochromic fluid with normal brain surface and there were no evidence of any vascular malformations. Marsupilization of the cystic lesion was carried out and she improved. The literature regarding arachnoid cyst with spontaneous intracranial haemorrhage is reviewed.