Endoscopic-Assisted Lateral Orbitotomy for Large Orbital Roof Dermoid Cysts With Dural Invasion

To demonstrate the technique and report the results of endoscopic-assisted lateral orbitotomy for 6 patients with huge intraorbital dermoid cyst causing orbital roof bone erosion and dural invasion.

Patients had unilateral cystic tumor with proptosis and hypoglobus for more than 6 months. There was no compressive optic neuropathy. Lateral orbitotomy procedure was performed from 2004 to 2016 by 1 surgeon. Cysts were dissected, and fluid content was aspirated to reduce the size. Solid contents were then suctioned, its cavity was repeatedly irrigated, and orbital part of epithelial lining was removed. The remained epithelial lining and keratinized content at the orbital roof (abutting the dura) were removed using the rigid endoscope lenses (4 mm, 0° and 30°) and curettage. Orbital tissue was pulled away from the roof (inferior) by an assistant surgeon to make a space for introducing the lens and curette. The surgical field was frequently irrigated. No orbital drain was used, and all the patients were discharged on the same day after 8-10 hours of observation. Skin sutures were removed 1 week later.

They were 4 men and 2 women with age range of 19-48 years. A large superolateral orbital tumor with roof erosion and dural invasion was observed on imaging. Procedures were performed uneventfully. Dermoid was the pathological diagnosis. While one patient lost to follow up after 1 week, others had 6-18 months follow-up time with no recurrence.

Endoscopic-assisted lateral orbitotomy approach provided a good field of view, illumination, and magnification to totally remove all the content and epithelial lining of very large orbital roof dermoid cysts with dural invasion.