Episcleral Apocrine Hidrocystoma Following Strabismus Surgery.

Apocrine hidrocystomas are benign cystic tumors derived from apocrine sweat glands; they are most commonly located in the skin of the head and neck regions. Ophthalmic occurrences typically appear at the lash line and canthi of the eyelid, although rare instances have been described in the conjunctiva, caruncle, and orbit. The authors illustrate an exceptional instance of a mobile episcleral cyst in a 12-year-old girl that developed about 2 years following strabismus surgery. The cyst was located anterior to the insertion of the left medial rectus and was excised in response to the patient's complaints of irritation. Histopathology of the excised specimen displayed an empty cyst lined by a double layer of cuboidal epithelium with the inner layer exhibiting apical decapitation secretion. Confirmatory immunohistochemistry demonstrated reactivity of both layers with CK7 and the outer myoepithelial layer with D2-40. Postoperative and traumatic cysts formed after interruption of the bulbar conjunctiva are usually conjunctival cysts lined by stratified squamous nonkeratinizing epithelium.