Ophthalmological examination of a 55-year-old white woman with longstanding ocular histoplasmosis syndrome (OHS) and recently diagnosed multiple sclerosis revealed poor central vision, peripapillary atrophy, extensive subretinal pigment deposition (fi gure), old choroidal neovascularisation (CNV; fi gure), and punched-out chorioretinal scars in the absence of any anterior segment and vitreous infl ammation. Cirrus HD retinal optical coherence tomography (OCT) scan revealed markedly disrupted topography of the internal limiting membrane and retinal pigment epithelium layers resulting from extensive chorioretinal scarring (fi gure). The so-called peaks and valleys seen on retinal OCT in this patient are in stark contrast to the smooth contours of these layers in eyes of healthy individuals. Characterised clinically by CNV and retinal scarring after exposure to histoplasma, OHS is thought to arise from spread of histoplasma spores that obstruct choroidal vessels in the eyes, although the fungus has only rarely been isolated from aff ected eyes. The patient likely developed OHS after prolonged exposure to chicken farms during young adulthood while living in the southern USA, a region known as the “Histo Belt” because of a high incidence of infection with histoplasmosis. In endemic areas within the USA, the Caribbean, and central and South America, OHS is a major cause of central vision loss in young adults. OHS, when accompanied by active CNV, can be treated with laser photocoagulation or injected anti-vascular endothelial growth factor therapy to prevent CNVinduced scarring. Our patient was previously treated with several courses of laser photocoagulation in the left eye, but was untreated in the depicted right eye because of the absence of active CNV. Her vision has remained stable for the past 10 years. Notably, OCT is an inexpensive tool for evaluation of retinal and macular pathology in a growing number of systemic disorders that result in ocular signs and symptoms.