Contact lenses in hypoxia.
Seven women with soft contact lenses were examined during a 4 h period in a decompression chamber. The atmospheric pressure was lowered from the normal value of 1000 millibars (750 mmHg) to 560 millibars (420 mmHg), which corresponds to the altitude of 4000 m above sea level. The humidity, temperature, percentage of carbon acid and illumination were attempted to be kept even. Five test subjects developed subjective, and all the 7 also developed objective eye symptoms. It was concluded that hypoxia itself may cause eye discomfort for aircraft passengers with contact lenses. The most serious objective findings were corneal erosions in 3 and opacities of corneal stroma in 5 test persons. The control group without contact lenses did not develop any symptoms during the test.
D000328:Adult; D001274:Atmospheric Pressure; D003263:Contact Lenses, Hydrophilic; D003318:Corneal Opacity / Q000209:etiology; D003664:Decompression; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000150:complications*