Ectopic brain tissue in the orbit.
PURPOSE: The authors report findings in a 9-month-old male infant with heterotopic brain tissue in the orbit, and compare and contrast the characteristics in this patient with the few other descriptions of such lesions in the literature. METHODS: Excisional biopsy of the growth was undertaken by means of an anterior orbitotomy. RESULTS: A 9-month-old male infant had a history of congenital left 'anophthalmia' and a slowly growing mass in the left orbit. An MRI scan revealed an orbital mass with solid and cystic components. Histological study of the excised tissue was performed and revealed a choristomatous arrangement of dysplastic brain tissue with intermixed primitive retina including pigmented epithelium. There was no connection between the orbit and cranial cavity. CONCLUSIONS: The mass must be considered a rare example of heterotopic brain tissue in the orbit and is the only instance we could find in the literature in which a formed eye was absent but in which a scattered primitive ocular structure could be identified.