Large orbital roof lesions with bone erosion and dural abutting could surgically be approached via either craniotomy or orbitotomy. Craniotomy is an invasive procedure with cosmetic and functional morbidities. On the other hand, orbitotomy (lateral and/or superior) provides a less invasive approach with lower morbidities but the area behind the superior orbital rim is not visible and therefore the risk of dural damage and incomplete removal of the dermoid (especially epithelial lining) are higher. The aim is to demonstrate endoscopic-assisted lateral orbitotomy for patients with a very large orbital roof dermoid cysts associated with orbital roof bone erosion and dural touch.

A classic lateral orbitotomy with bone flap was performed. Dermoid was dissected and freed from the other orbital tissue. It was punctured and its content was suctioned (syringe) to reduce the size. The epithelial lining was incised laterally, remaining dermoid content was suctioned, and the cavity was repeatedly irrigated to completely remove the contents. Epithelial lining of dermoid was gradually dissected and totally removed from the orbital side. Finally, dermoid content and epithelium abutting the dura and causing orbital roof erosion were removed using endoscopically assisted curettage (Video)

Procedures were performed uneventfully on 5 patients (age range: 23-48 years old) from 2006 to 2012. Specimens (contents and dermoid wall) were sent for pathology. No orbital drain was used. Sutures were removed 1 week later. No ocular and or orbital complications were observed at early or late postoperative follow ups. No recurrence was reported and observed in the last follow up times.

The endoscopic-assisted orbitotomy approach enabled safe removal of very large dermoid cysts with orbital roof erosion and dural touch and provided an effective and less invasive alternative to a frontal craniotomy.