OBJECTIVETo investigate the hearing change when chronic tinnitus acute aggravated and the affect of prognosis due to hearing change.

METHODSThe pure tone threshold and acoustic immittance were used for every case in the acute aggravation of chronic tinnitus (AACT) group, and for some of AACT group members the auditory brainstem response (ABR), distort-product otoacoustic emission (DPOAE), electrocochleogram (EcochG), glycerin test and MRI were used at the same time for further diagnosis. For the chronic tinnitus, the patients accepted the intervention of tinnitus retraining therapy (TRT) both for the AACT group and the control group. As for the recent hearing loss appeared in the AACT group members, the patients were treated the cases as the sudden deafness, and then the hearing characteristic of the AACT group was analyzed and the effect of the chronic tinnitus both for the AACT group and control group after the TRT for 3, 6, 9 and 12 months was evaluated.

RESULTSThree kinds of hearing changes appeared when chronic tinnitus acute aggravated. Based on the dated high frequencies hearing loss ranged 4-8 kHz, recent hearing loss appeared in 1-2 middle frequencies near the impaired high frequencies; Based on the dated single middle frequency hearing loss, another middle frequency hearing impaired near the dated hearing loss frequency, the sawtooth-like audiogram changed to groove-like audiogram; Hearing fluctuation in low frequency area, hearing threshold increased 10-30 dB in 125-1000 Hz but kept unchanged in the high frequency area. The recent local frequency hearing loss healed after the vasodilator and neurotrophic drugs therapy, but the dated hearing loss can't rehabilitate. Along with the rehabilitation of recent local hearing loss, 25 of 32 cases chronic tinnitus victims get to habituation; this finding showed that the experience of tinnitus aggravation and relief accelerated the habituation. Until the 12 months after the TRT, the curative effect difference between AACT group and control group showed statistical significance.

CONCLUSIONSWhen the chronic tinnitus acute aggravated, 3 kinds of local area hearing impaired. Timely diagnosis and effective treatment had brought not only hearing rehabilitation but also promotion to habituation of chronic tinnitus.