A CLINICAL OBSERVATION OF ACOUSTIC LESION CAUSED BY HEAD INJURY

Abstract

Following results were obtained through the clinical examination of 603 head injury cases from labour accidents. 1.Statistics of these patients from the view point of sex, age, profession, kind of injury, location of injury, period until the examination, unconsciousness, farcture, bleeding, paralysis of the cranial nerve, subjective symptoms, etc.were showed. 2.In 52.8% of the cases showed subjective deafness, while 61.1% showed objective deafness. The average hearing losses of speech range was below 30db in 76.6%, and over 81db in 2.8% of the cases, being perceptive type in 86.6%, mixed type in 9.8%, and total deafness in 2.7%.On audiogram, gradual high tone loss form was seen in most of the cases and then following order: flat form, abrupt high tone loss form, and dip form. 3.Tinnitus was observed in 51.1% of the cases.Habitual tinnitus was seen a little more fre- quently than the occasional one.In 80% of the case which had tinnitus, objective deafness was recognized. 4.Subjective disturbance of veslibular function was seen in 57.1% and objective disturbance was seen in 48.7% of the cases.Eighty percent of patients showed positive Romberg test and 52.6% showed abnormality in stepping test, 12.8g% showed abnormality in postrotatoric nystagmus, and 34.9% showed the same in caloric nystagmus. 5.Finding of the ear drum, patency of the custachian tube, and results of differential hearing test, namely Noise Test, Fowler Balance Test, Temporary Threshold Shift, Fatigue Test, Differe- nce Limen Test, was showed.Furthermore the pathogenesis of auditory disturbance caused by head injury and its treatment were discussed.