眼瞼下垂を呈した上眼瞼結膜囊胞の1例

A Case of Upper Eyelid Conjunctival Cyst with Ptosis

はじめに

　結膜囊胞（conjunctival cyst）は，結膜の上皮組織が粘膜固有層に迷入することにより発生する良性病変である。そのほとんどが球結膜からの発生例として眼科領域で報告されており，形成外科領域での報告は少ない。

　今回われわれは，右上眼瞼に生じて眼瞼下垂を引き起こした結膜囊胞の1例を経験した。外科的切除を行い，良好な結果を得たので，文献的考察を加えて報告する。

　A 24-year-old man presented with a 4-year history of gradual onset of right eye ptosis after a right upper eyelid injury 5 years prior to presentation. Computed tomography and magnetic resonance imaging revealed a uniformly dense, well-circumscribed intraorbital tumor. We performed a total surgical excision for radical cure. Intraoperatively, we detected a transparent yellow cyst （20×10 mm） in the submucosa of the levator tendon and Müller’s muscle, and we removed the entire cyst. The histopathological evaluation showed that the cystic lumen was lined with several layers of columnar epithelium with minimal atypia. The lesion was diagnosed as a conjunctival cyst. Ptosis improved without any cosmetic concerns postoperatively.

　This conjunctival cyst was a benign elevated tumor of the type that was first reported by Jacoby in 1987. Patients with this tumor primarily present for consultation with cosmetic concerns and a foreign body sensation; few reports have described ptosis as a complication of these tumors. Conjunctival cysts should be considered as part of the differential diagnosis in patients with suspected cystic disease within the orbit of the eyelid.