Cranio-Orbital Fibrous Dysplasia Manifesting as Contralateral Optic Neuropathy

A 38-year-old woman with longstanding right facial malformation presented for blurred vision in her left eye (OS). Examination revealed right zygomaticotemporal prominence (A), left afferent pupillary defect, dyschromatopsia, and optic disc pallor with 20/20 vision. Automated perimetry demonstrated nonspecific losses OS, and OCT exhibited retinal nerve fiber and ganglion cell thinning (B). Magnetic resonance imaging showed right extracranial bone mass (arrowheads), sparing the ipsilateral orbit, with left optic canal involvement (C, arrow). The optic canal was decompressed, and tumor resected via craniotomy. Histopathology showed curvilinear bony trabeculae without osteoblastic rimming, confirming fibrous dysplasia (D; hematoxylin and eosin, ×2-×4). Five months postoperatively, vision measured 20/30 with inferior field losses. (Magnified version of Figure A-D is available online at www.aaojournal.org).