Lipid Subhyaloid Maculopathy and Exposure to High Altitude.

BACKGROUND: High altitude retinopathy (HAR) includes a number of diseases related to high altitude such as acute mountain sickness (AMS), high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE). High altitude retinopathy is mainly characterized by retinal hemorrhages, usually sparing the macular region, a condition specifically known as high altitude retinal hemorrhages (HARH). The pathogenesis of HARH is unclear. Many studies show that lack of oxygen causes an inadequate autoregulation of retinal circulation, causing vascular incompetence. Other retinal changes described in HAR have been reported, such as optical disk edema, optic disc hyperemia, cotton wool exudates, venous occlusions, and macular edema.

CASE REPORT: In this paper we present a case of an aviator who developed a unilateral maculopathy through subhyaloid lipid accumulation on a climb to the top of Mt. Everest. The clinical findings are suggestive of an apparent case of temporary altitude-induced visual disruption maybe by the same presumable pathogenesis of HARH. Right eye visual loss was perceived at 5150 m when he was trying to take a photograph 40 d into the expedition.

DISCUSSION: The maculopathy developed by this patient adds to the discussion on the pathogenesis of HARH, especially the aspect of this maculopathy and its complete resolution. It seems that autoregulation failure could lead to exudation and lipid deposits in the foveal area. Although macular damage is not a common signal in HARH, checking visual acuity during high altitude expeditions remains an important procedure to avoid late diagnosis as unilateral blindness may not be detected early. Rosas Petrocinio R, Gomes ED. Lipid subhyaloid maculopathy and exposure to high altitude. Aerosp Med Hum Perform. 2016; 87(10):898-900.