| Popis: |
A little more than one hundred years ago an aeronaut complained of loss of hearing following a descent from 29,000 feet (8,839 meters) in a balloon. 1 His disability must have been considered trivial to inspire so few words in the historical record. Today this condition, associated with aero-otitis media, 2 is the subject of widespread interest, challenging the attention of every one seeking to reduce its incidence. The traumatizing barometric pressure changes occurring in the middle ear during descent in flight must be classified among the influences which may impair hearing. Variations of pressure produced in the middle ear during ascent and descent exert only fleeting changes in hearing when prompt intermittent compensation is successfully affected by adequately functioning eustachian tubes. Personnel who have been trained in the technic of ventilating their middle ears undergo literally hundreds of such pressure cycles with practically no known ill effects. The transitory subjective fading |
