The impact of cochlear implantation on quality of life and psychological status in single-sided deafness or asymmetric hearing loss with tinnitus and influencing factors of implantation intention: a preliminary study.

PURPOSE: The current study aims to explore the therapeutic effect of cochlear implants (CIs) on tinnitus in patients with single-sided deafness or asymmetric hearing loss (SSD/AHL) as well as the improvement of tinnitus-related quality of life and psychological status. In addition, we also explored whether the levels of quality of life and psychological status was related to the patient's implantation intention. METHODS: Seven patients decided to receive cochlear implantation. Before and after implantation, they completed the Visual Analogue Scale (VAS) and the Tinnitus Questionnaire (TQ) to assess tinnitus severity, the Speech, Spatial and Qualities of Hearing Scale (SSQ), and the Medical Outcomes Study Short Form 36 Health Survey Questionnaire (SF-36) to assess the quality of life, the Simplified Coping Style Questionnaire (SCSQ) to assess psychological status. The other 8 SSD patients refused cochlear implantation. Their scores of the above questionnaires were compared with those of patients received implantation. RESULTS: Six months after cochlear implantations, the tinnitus perception, loudness, and annoyance significantly decreased compared to that before implantation. In terms of quality of life and physiological status, no statistically significant changes were detected in SSQ, SF-36, and SCSQ measurements. The score of annoyance subcategory of VAS and all subcategories of SSQ of patients refused implantation were better than those of implanted patients before implantation. CONCLUSIONS: These results suggest that CIs can significantly reduce tinnitus severity. Patients refused implantation had better status in the annoyance of VAS and all subcategories of SSQ scores than those received implantation.

CoCl2 -simulated hypoxia potentiates the osteogenic differentiation of fibroblasts derived from tympanosclerosis by upregulating the expression of BMP-2.

Tympanosclerosis (TS) is a result of long-standing middle ear inflammation characterized by fibroblasts ossification. Fibrosis is the last revertible stage in the progress of middle ear inflammation to TS. It was hypothesized that chronic hypoxia could be modulating fibrosis, which in turn additionally further aggravated hypoxia via decreasing oxygen diffusion. However, the effects of hypoxia on osteoinductive activity of fibroblasts have not been explored. Herein, we purposed to explore the role of hypoxia in osteogenic differentiation of fibroblasts derived from TS. The expression of bone morphogenetic protein-2 (BMP-2), hypoxia-inducible factor-1α (HIF-1α), and Vimentin in the human surgical specimens of tympansclerosis was investigated by immunofluorescent staining. Furthermore, cultured fibroblasts were stratified into the following study groups: control, 25, 50, and 100 µM cobaltous chloride (CoCl2 ) group. BMP-2, as well as HIF-1α levels of expression were detected via western blotting and immunofluorescence analysis. We found that the expression of BMP-2 and HIF-1α was significantly upregulated in TS tissues and these fibroblasts, which was vimentin positive surrounding sclerotic plaques, were also expressing HIF-1α positive. The results also demonstrated that CoCl2 treatment increased nuclear HIF-1α protein level in the fibroblast. Furthermore, treatment with CoCl2 significantly increased BMP-2 expression and remarkably elevated alkaline phosphatse activity and the mineralized nodules area. These data illustrate that hypoxia may play an osteogenic role in TS fibroblasts via the elevated expression of a possible osteogenic factor, BMP-2.

Forward Electric Stimulation-Induced Interference in Intracochlear Electrocochleography of Acoustic Stimulation in the Cochlea of Guinea Pigs.

Electric-acoustic stimulation (EAS) uses amplified sound by a hearing aid to stimulate an apical low-frequency region of the cochlea and electrical current from a cochlear implant (CI) to stimulate the basal high-frequency region. EAS recipients had significantly improved speech perception, music appreciation, and hearing function in noise compared to those relying on CI electrical stimulation (ES) alone. However, the interaction between basal ES and apical acoustic stimulation (AS) in the cochlea potentially affects EAS advantages. To investigate ES-AS interaction, we designed a system that recorded the electrically evoked compound action potential (ECAP) and the auditory evoked potential (AEP). We used an intracochlear electrode array to deliver ES at the basal cochlea and detect intracochlear electrocochleography (iECochG) generated from apical AS. Within iECochG, 3 or 6 dB (double or quadruple intensity of ECAP threshold) electric stimulation, 1 ms-forward ES significantly increased CAP amplitudes of 4 kHz/20 dB AS compared to 0 dB ES. Notably, 1 ms-forward 3 dB ES significantly increased CAP amplitudes of 4 kHz/20 dB AS, while 3 or 5 ms-forward ES did not change the CAP amplitudes. The elevation in CAP amplitude of 40 dB/4 kHz AS induced by 1 ms-forward 3 dB ES was significantly lower than that in 20 dB/4 kHz AS. With 1 ms-forward 3 dB ES, AS frequency and stimulating electrode location have no significant impact on relative CAP amplitudes of 20 dB AS. These results suggest that the basal forward ES and the following apical AS could produce a cumulative effect on the auditory nerve response.