Paediatric orbital conjunctival epithelial cyst with positive asialotransferrin

Conjunctival orbital cysts are rare; they are typically either conjunctival dermoid or conjunctival epithelial cysts - congenital or acquired (inclusion). We describe the case of a 15-month-old girl presenting with strabismus and proptosis who had a retrobulbar intraconal cystic lesion displacing the optic nerve, with an adjacent middle cranial fossa anomaly. Aspiration of the orbital cyst tested positive for asialotransferrin, raising the suspicion of a direct communication with cerebrospinal fluid (CSF). Subsequent fine cut CT scanning disproved any connection with the intracranial space, and the cyst was excised complete and intact. Histopathology showed a conjunctival epithelial cyst. To our knowledge, this is the first case report in the literature of an asialotransferrin positive pediatric orbital conjunctival epithelial cyst. It is of clinical relevance as it explores the possibility of either a false positive asialotransferrin or potentially a prior developmental communication with the subarachnoid space. These two diagnostic possibilities are discussed.