TY - CHAP M1 - Book, Section TI - High-Altitude Retinal Hemorrhage A1 - Zafren, Ken A1 - Thurman, R. Jason A1 - Jones, Ian D. A2 - Knoop, Kevin J. A2 - Stack, Lawrence B. A2 - Storrow, Alan B. A2 - Thurman, R. Jason PY - 2021 T2 - The Atlas of Emergency Medicine, 5e AB - Retinal hemorrhages are common above 5200 m (17,000 ft) and are not usually associated with acute mountain sickness (AMS). High-altitude retinal hemorrhages (HARHs) are rarely symptomatic, but if found over the macula, these hemorrhages may cause temporary blindness. The diagnosis can be established by ophthalmoscopy. Without visualization of the lesion, the differential diagnosis of unilaterally decreased vision or blindness at high altitude includes migraine equivalent, cerebrovascular accident, and dry eye (often unilateral, due to strong winds), as well as all conditions found at sea level. SN - PB - McGraw-Hill CY - New York, NY Y2 - 2024/03/28 UR - accessemergencymedicine.mhmedical.com/content.aspx?aid=1181050796 ER -