Objective: To study the relationship between loudness recruitment and abnormal cochlear mechanism.
Methods: The basic properties of input/output (I/O) of distortion product otoacoustic emission (DPOAE) in 20 normal subjects(40 ears) and 50 cases with cochlear deafness (63 ears) with positive recruitment were studied and analyzed.
Results: Average slope of I/O at different frequencies in all deaf ears with recruitment was greater than those in the normal subjects with a statistical significance (P < 0.01). Moreover, thresholds of DPOAE in the recruitment positive ears were higher than those in normal subjects.
Conclusion: Loudness recruitment and abnormal cochlear active mechanism are specially related. I/O functions of DPOAE are more perceptive and precise to appraise cochlear active mechanism. It probably may become a valuable test for early diagnosis of cochlear deafness.