The negative acoustic reflex in retrocochlear disorders.
The most frequent impedance abnormality of an acoustic tumor is an absent reflex. However, this finding also occurs with middle ear disorders and is therefore nonspecific. This study recorded the contralateral acoustic reflex of human subjects suspected of having an acoustic tumor. Many tumor subjects, by visual inspection of the impedance bridge balance meter, appeared to have an absent reflex. Most of these subjects, in fact, had small amplitude negative reflexes by offline analysis on an averaging computer. Recognition of these negative reflexes increases the specificity and sensitivity of the reflex test for acoustic tumors. We recommend reflex testing with averaging computer monitoring to ensure their recognition.
D000158:Acoustic Impedance Tests; D000328:Adult; D003051:Cochlea; D004428:Ear Neoplasms / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007759:Labyrinth Diseases / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000175:diagnosis / Q000503:physiopathology*; D012022:Reflex, Acoustic