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Objective Visual take-over of the auditory cortex in prelingual deaf children has been widely reported. However, there have been few studies on visual cortex plasticity after cochlear implantation (CI). In this study, we investigated the hypothesis that extrinsic auditory stimulation following CI in prelingual deafened children can induce visual cortex plasticity. Method Visual evoked potentials (VEPs) were recorded in 37 CI children (4 groups with different use times) and 8 control subjects, in response to sound and nonsound stimuli. Latency and amplitude were analyzed for the P1, N1 and P2 components on the Oz electrode. Comparisons of VEP were conducted between the sound and nonsound stimuli and among different groups in order to view evidence of visual cortex reorganization. Results The latency of the P2 component was significantly longer at the occipital site (Oz) in CI 0M than those in the other four groups. After the effect of age was excluded, a significant negative correlation was found between CI usage and P2 latency of nonsound stimuli. Occipital P1N1 latency and P1 amplitude were not affected by group or stimulus category. However, the N1 and P2 amplitudes were significantly larger in response to a sound stimulus than to a nonsound stimulus. Conclusion Our findings suggest that P2 latency develops with CI usage and may be a biomarker of visual cortex plasticity.

The hypoxia-inducible factor and vascular endothelial growth factor (HIF-VEGF) pathway in hypoxic conditions of the middle ear due to dysfunction of the eustachian tube is still unknown, but it is considered as one pathogenetic mechanism in otitis media. This study was designed to investigate the possible involvement of the HIF-VEFG pathway in otitis media with effusion induced by dysfunction of the eustachian tube. We adopted a soft palate approach to obstruct the orifice of the eustachian tube to establish otitis media in a rat model. Auditory evoked brainstem response and tympanometry were used as hearing function tests, hypoxia-related factors were examined by reverse transcriptase polymerase chain reaction (RT-PCR). The expression of hypoxia-related proteins was detected by Western blot and immunostaining. The model of otitis media with effusion was successfully induced by cauterizing the orifice of the eustachian tube. RT-PCR showed up-regulation of hypoxia-related factors in cauterized ears. Western blot and immunostaining showed that the expression of hypoxia-related proteins in cauterized ears was increased. Hypoxia-induced vascular proliferation and an increase in permeability may be one pathogenetic mechanism of otitis media due to dysfunction of the eustachian tube.

To verify the relationship between THI and VAS scores in patients with sudden hearing loss and tinnitus in a prospective study.Forty-four patients classified their tinnitus according to VAS and THI before and after treatment, and both scores were compared through the Pearson's correlation coefficient test and Nonparametric tests.There was a correlation between VAS and THI scores in patients with sudden hearing loss and tinnitus. Tinnitus assessment scores were significantly reduced after treatment. Decreasing of THI and VAS scores were not depended on frequency and loudness of tinnitus and severity of deafness, but therapeutic effect of sudden sensorineural hearing loss.THI and VAS scores are useful for assessment of tinnitus in patients with sudden hearing loss and tinnitus.

To investigate the effect of Eustachian tube balloon dilation (ETBD) in treatment of eustachian tube related diseases.Fifteen cases (20 ears) of otitis media with effusion and 22 cases (30 ears) of symptomatic Eustachian tube dysfunction were recruited. Technique of tubomanometry (TMM) showed obstructive Eustachian tube dysfunction in all patients. All the patients were received ETBD and followed up with VAS evaluation of ear fullness, muffled hearing, poping sound in the ear and tinnitus. And also the TMM change and middle ear effusion.Ear fullness, muffled hearing released with 1 week (ear fullness: 8.2 ± 1.4 vs. 2.0 ± 1.2, P0.05, muffled hearing: 6.2 ± 1.2 vs. 3.1 ± 0.8, P0.05). No recurrence was seemed within 6 months. The eustachian function test turned better. Symptomatic Eustachian tube dysfunction had an effective rate of 96.6% while otitis media with effusion was 95.0%.ETBD have good short-term effect in obstructive eustachian tube dysfunction related middle ear dysfunction, which might provide a good way to solve the eustachian tube related diseases.

To investigate hidden hearing loss in tinnitus patients with normal audiograms by means of auditory brainstem response (ABR) and explore the origin of tinnitus.Pure tone thresholds, ABR thresholds, amplitude of wave I and wave V of ABR were analyzed in 40 tinnitus patients and 15 controls.There was no significantly difference in pure tone thresholds and ABR thresholds between those tinnitus patients and controls while a reduced amplitude of wave I and normal amplitude of wave V of ABR in the tinnitus patients became evident.Tinnitus patients with normal audiograms have hidden hearing loss at the level of primary auditory nerve and the generation of tinnitus is likely attributed to a homeostatic response of neurons in brainstem.

Comparison of the sensitivity of Sp/Ap amplitude and area ratio in the aid of diagnosis of Meniere's disease. Meniere's disease was defined by the 1995 American Academy of Otolaryngology-Head and Neck Surgery Committee on Hearing and Equilibrium.The study sample consisted of 35 patients in our hospital, who were undergone tympanic electrocochleography (EcochG). A control group of 10 patients (20 ears) with normal Sp/Ap ratio and EcochG data were identified. Sp/Ap amplitude and area curve ratios for both group were measured.The traditional upper limit and the upper limit of normal for Sp/Ap amplitude and area curve were respectively 0.4, 46 and 1.94. Of 35 patients with Meniere's disease, had an abnormal Sp/Ap amplitude ratio,and had an abnormal Sp/Ap area curve ratio; the difference between groups was statistically significant.Sp/Ap curve area curve ratio is more sensitive than conventional Sp/Ap amplitude ratios in diagnosis of Meniere's disease.

To explore the correlation between childhood obstructive sleep apnea-hypopnea syndrome and tympanogram.A prospective clinical study was carried out. Polysomnography and tympanogram were analyzed in 72 cases.Among the 144 ears 37 ears had type C or B tympanogram. There was no correlation between tympanogram and LSaO2. It was found correlation between tympanogram and AHI (P0.05).Hypoxemia may affect middle-ear function. It was necessary to do the examination of acoustic impedance routinely in children with moderate and severe OSAHS.