Nonarteritic anterior ischemic optic neuropathy (NAION) in the left eye of a 53-year-old man patient with a history of hypercholesterolemia. The right optic disk is pink and flat (a). Automated perimetry, using the Humphrey visual field 24-2 protocol, shows a normal visual field (b), with the dark spot in the temporal field being the physiologic blind spot. Acutely, the left optic disk appears swollen and hyperemic, with hemorrhage at the superior and temporal disk margin (c). Automated perimetry shows diffuse visual-field loss, more marked in the inferior aspect of the field (d). On review at 6 months, the optic disk swelling has resolved and the disk appears diffusely pale and atrophic (e). Automated perimetry shows improvement in the superior visual field, with a persistent inferior altitudinal defect (f).A case of recurrent transient monocular visual loss after receiving sildenafil. Ghanem AG - Case reports in ophthalmological medicine (2011). Not Altered. CC.