ABSTRACT
The effects of acute (4350 m), subacute (4800 m) and chronic (4800 m) altitude hypoxia on colour vision in the green/red axis were explored in eight sea-level natives by means of a simple portable anomaloscope. Subjects were required to create a yellow colour from a mixture of red (635 nm) and green (565 nm) obtained from two electroluminescent diodes. A relative decrease in green, compared to red, sensitivity was observed in each hypoxic condition (p less than 0.001). Acclimatization to altitude, evidenced by the improvement of arterial O2 saturation (earoximeter) was accompanied by a slight but not significant return to normal colour sensitivities. The influence of factors such as fatigue, season, and age is discussed and does not seem likely to account for the observed variations.
Subject(s)
Altitude Sickness/physiopathology , Color Perception Tests/instrumentation , Color Perception/physiology , Hypoxia/physiopathology , Acclimatization , Acute Disease , Adult , Altitude , Chronic Disease , Humans , Middle AgedABSTRACT
Ocular electrophysiology investigations are essential for detecting retinal complications of prolonged treatment with synthetic antimalarial agents. The techniques employed and the principal lesions discovered by the examination are described. The analysis of lesions found in 29 out of 120 cases examined showed that only simple close surveillance was necessary in 17 cases, a reduction in daily dosage in 11 cases, and interruption of treatment in one case only. The modalities of ocular electrophysiology surveillance during prolonged treatment with antimalarial agents are outlined.
