The behaviour of wave V latency in cochlear hearing loss.
The audiological approach to the early diagnosis of cerebellopontine angle tumours (APC) is based mainly on ABR. In present work, wave V latency has been studied in two groups of patients: 308 cochlear cases and 74 retrocochlear cases (APC surgically confirmed tumours), in order to increase the sensitivity and specificity of the diagnostic indexes I-V, IT5 and Delta V. Wave V latencies have been evaluated in relation to hearing loss at 2-4 kHz and audiometric profile. Both these factors show a highly significant positive correlation with the latency, which consequently increases proportionally to hearing loss and high-frequency audiometric loss. A multiple regression analysis was therefore used to analyse the effects from the two variables, and a correction factor was calculated to compensate the latency values for hearing loss and threshold configuration. The effects of such a correction on the clinical results consist mainly of a reduction in the rate of cochlear false-negative results, which corresponds to improving the ABR specificity.
Arslan
E
E
Department of Audiology, University of Ferrara, Italy.
Prosser
S
S
Rosignoli
M
M
D001300:Audiometry, Evoked Response; D001933:Brain Stem / Q000502:physiology; D002528:Cerebellar Neoplasms / Q000175:diagnosis*; D002530:Cerebellopontine Angle; D005072:Evoked Potentials, Auditory; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis