Orbital hydatid cyst with diverse locality in the orbit and review of literatures.

PURPOSE to introduce five different type of orbital involvement by hydatid cyst in 8 consecutive patients. DESIGN descriptive case series. METHODS Herein 8 patients with slowly progressive proptosis from 2 to 4months earlier at their first presentation are introduced. Complete ophthalmic examinations were done. Complete blood count, serologic test, ESR (erythrocyte sedimentation rate), CT scan and MRI were requested. Surgical removal of the lesions performed in all patients. RESULT The hydatid cysts found in the extraconal (2 patients) and intraconal space (3 patients), lacrimal gland (1 patient), medial rectus (1 patient) and intraosseous of orbital wall (1 patient). The diagnosis of the isolated orbital hydatid cyst without any lesion in other parts of the body was confirmed in all patients. The recurrence was not observed in any patients during 2 - 6 years follow up. CONCLUSION Although the most common site of involvement of orbital hydatid cyst is intraconal, it can invade various locations within the orbit.