INNER-EAR DISORDERS DUE TO PRESSURE CHANGE

We reviewed the records of 136 patients who had inner ear disorders in cluding hearing loss and vertigo caused by pressure change. We divided them into three groups, according to the aetiology: group A, change i n atmospheric pressure (diving, airplane travel, etc.); group B, rapid change in ear pressure in normal atmosphere (nose blowing, heavy lift ing, etc.); and group C, blast injury. A flat initial audiogram was th e most common type in groups A and B. In group C, high-tone hearing lo ss was the most common type of audiogram. These results correspond to findings previously reported in animal experiments. Exploratory tympan otomy was performed more than 12 days after the pressure change in 16 patients. Although the vertigo disappeared after surgery, hearing did not improve.