Posterior ischemic optic neuropathy following functional endoscopic sinus surgery

Abstract

Posterior ischemic optic neuropathy (PION) is a rare condition resulting from ischemia of the retrobulbar optic nerve and manifests with acute, painless vision loss. We describe a case of a 46-year-old male who presented with PION in his left eye following uncomplicated functional endoscopic sinus surgery for sinus obstruction in the setting of frequent cocaine use. Postoperatively, the patient reported complete vision loss in his left eye, and MRI displayed diffusion weighted signal hyperintensity in the left optic nerve suggestive of optic nerve ischemia. The patient completed a steroid taper, with subsequent examination revealing a visual acuity of 20/20, afferent pupillary defect, unremarkable fundoscopic examination, and inferotemporal and superior altitudinal visual field defects. Fluorescein angiography displayed leakage from the inferonasal aspect of the optic disc and vessels. In the months following surgery, the patient demonstrated complete recovery of central vision, near complete resolution of the afferent pupillary defect, persistent peripheral vision loss, and improvement in sinus symptoms, including improved breathing, resolution of sinus pain, and minimal mucosal edema.