Ocular Motility Disturbances in Orbitofacial Neurofibromatosis Type 1 (P6.295)

OBJECTIVE: To evaluate the causes and types of ocular motility disturbance in a group of patients with orbitofacial neurofibromatosis type 1 (OFNF). BACKGROUND: OFNF refers to progressive, often disfiguring, tumors of the lid, brow, temple, face, and orbit occurring early in life in some patients with neurofibromatosis type 1 (NF1). OFNF is associated with sphenoid and orbital dysplasia, neurofibromas involving the orbit and cavernous sinus, and enlargement of the globe, all of which can affect ocular motility. DESIGN/METHODS: Retrospective medical record review and re-examination of selected patients from one institution. RESULTS: Forty-nine patients met National Institutes of Health criteria for OFNF and had adequate clinical and neuroimaging information to assess ocular motility and factors affecting eye movements. Fourteen patients had no strabismus, all of whom had good vision with no ductional abnormalities on either side despite large globes, sphenoid dysplasia, and neurofibromas in the orbit and/or cavernous sinus in many. Eight patients with comitant strabismus also had no ductional abnormalities with a similar constellation of anatomic abnormalities, but these patients all had poor vision in at least one eye. Twenty-seven patients had incomitant strabismus, all with downward displacement of the globe and ductional limitations. CONCLUSIONS: Anatomic changes associated with OFNF do not always cause ocular motility abnormalities. Strabismus generally was not present when ocular motility was full and visual acuity was good despite substantial distortion of orbit and sphenoid anatomy and tumor in orbit and/or cavernous sinus. Comitant strabismus occurred with full ocular motility and reduced vision in at least one eye. Incomitant strabismus was always accompanied by reduced vision and a ductional abnormality in one or both eyes that in general seemed due to anatomic abnormalities of the orbit and skull rather than to partial or complete cranial nerve palsy. Ductional abnormalities in OFNF are currently difficult or impossible to treat. Study Supported by: King Abdulaziz City for Science and Technology, Riyadh, Saudi Arabia [Project AT-30-20] Disclosure: Dr. Bosley has nothing to disclose. Dr. Alorainy has nothing to disclose. Dr. Morales has nothing to disclose. Dr. Chaudhry has nothing to disclose. Dr. Oystreck has nothing to disclose.