Endoscopic and trans-fornix removal of a giant orbital-ethmoidal osteoma.

A 39-year old female was referred with a 2 year history of slowly progressive headache, exophthalmos, diplopia and restricted eye movements with exotropia of the right eye. Orthoptic examination revealed restricted elevation and mildly restricted adduction of the right eye. CT and MRI demonstrated a large (35 x 20 x 23 mm) calcified infraorbital lesion extending into the ethmoidal sinus. Because the visual field defects were progressive and the acuity OD dropped to 20/80 surgical intervention was necessary. The osteoma was successfully removed using an inferior and medial orbitotomy with swinging eyelid combined with an endoscopic approach. In a second procedure the orbital floor was reconstructed with a porous polyethylene (Medpor) implant. A final procedure consisted of a 3 mm recession of the left superior rectus muscle and infundibulotomy by the sinus surgeon to open the blocked maxillary sinus. After 6 months visual acuity OD had returned to 20/20. Orthoptic examination showed normal binocular function.