Apical involvement with fibrous dysplasia: Implications for vision

Purpose: To describe the ophthalmic findings of fibrous dysplasia of the orbit. Methods: Prospective case series. Twenty-one patients with fibrous dysplasia with orbital involvement underwent a complete ophthalmic examination and orbital imaging by CT. Results: Four of the 21 patients had McCune-Albright syndrome and I had tuberous sclerosis. In 17 patients (81%), the disease was restricted to, the cramofacial region. Facial distortion, proptosis, and eye dystopia were detected in 62% of the patients. Nasolacrimal duct obstruction and strabismus were detected in only I and 2 patients, respectively. Of the 34 orbits affected, the roof was affected in 67.6%. The floor was the least affected wall. For most orbits, the disease was seen in more than 1 wall, and in 9 orbits (26.5%) all 4 walls were involved. Twelve orbits (35.2%) showed cysts on CT within the affected bones. In 19 orbits (55.9%), the optic canal was circumferenti ally narrowed. Blindness was detected in only I patient who had undergone optic canal decompression. Conclusions: The main consequences of orbital involvement in fibrous dysplasia are eye dystopia and proptosis. Apical involvement is a common feature. Optic canal narrowing does not necessarily induce vision loss. We believe that patients with apical involvement should be carefully followed and have their apices decompressed only when their vision is clearly deteriorating. Our data do not support prophylactic optic canal decompression as a therapeutic measure.