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To the Editor.—Retinal hemorrhages have been described in a patient, the wife of a physician from Arizona, in QUESTIONS AND ANSWERS (239:1208, 1978). The patient had not been fully acclimatized even to moderate altitudes. The severe diarrhea and attendant cramping that lasted one week certainly could have produced occasional Valsalva strains.A Valsalva maneuver, if sudden and of sufficient magnitude, may produce superficial retinal hemorrhages in perfectly normal persons. This is called Valsalva hemorrhagic retinopathy.1 It occurs much more frequently in various anoxic conditions that lower the permeability of the retinal capillaries. Under these circumstances even moderately increased intravenous pressure, such as occurs in stooping, lifting, sneezing and coughing, and straining at stool, will produce the stress necessary for retinal extravasation. For instance, we have noted retinal hemorrhages in patients who have been mountain climbing,2-4 who have anemia (and leukemia), and who have had nonfatal carbon monoxide |
