An unusual case of retrobulbar arachnoid cyst and its management.

Arachnoid cysts are collection of cerebrospinal fluid contained inside a cavity lined by leptomeninges. It constitutes 1% of all intracranial tumours mostly present in the middle cranial fossa. Retrobulbar arachnoid cyst in elderly persons are a rare occurrence. We report a rare case of retrobulbar arachnoid cyst with ophthalmic manifestations and its effective management. CT-guided aspiration of the cyst and subsequent cytological and biochemical test revealed an arachnoid cyst. Patient is on a 5-year follow up without recurrence and improvement of the vision in the affected eye.