Primary Orbital Hydatid Cyst

Abstract

The authors want to highlight the importance of clinical, radiological and histopathological evaluation in unilateral proptosis. A 17-yearold male presented with left progressive nonpulsatile proptosis, lateral gaze diplopia and decreased visual acuity. It was diagnosed as orbital hydatid cyst on CT scan and MRI. The patient was successfully operated with near total recovery of the vision. Radiological investigation showed a circumscribed cystic lesion lateral to orbit separate from the lacrimal gland. Intraoperative cysts and postoperative histopathology confirmed the primary orbital hydatid cyst. Although rare there is always a possibility of a primary hydatid in patients with unilateral proptosis, restricted eye movements and lateral decreased visual acuity. This is possible even when the Casoni's test is negative. Surgical excision with postoperative albendazole is the effective treatment for the cure of disease.