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Abstract Introduction Measurement of the electrically-evoked stapedial reflex threshold (ESRT) is an objective tool used to set the comfort levels in pediatric cochlear implant (PCI) users. The levels of ESRT have a strong correlation with comfort levels. However, the clinical utility of ESRT is limited because the ESRT response is not observed in all cochlear implant users. Objective To assess the effects of probe-tone frequency on ESRT and its relationship with the behavioral comfort levels in PCI users. Methods A total of 14 PCI users aged between 5 and 8 years participated in the study. The ESRT levels were measured using high-frequency probe tones (678 Hz and 1,000 Hz), and the default 226 Hz probe tone. The ESRT was measured with single-electrode stimulation across the three electrode locations (basal [E01]; middle [E11]; and apical [E22]). The ESRT levels measured with different probe tone frequencies were compared with the behavioral comfort levels. Results The mean ESRT levels using 1,000Hz and 678 Hz were lower than those measured using 226 Hz, but there was no main effect of probe-tone frequency (p > 0.05). A significantly high incidence of successful ESRT measurements occurred with higher-frequency probe tone (p < 0.039). Additionally, ESRT using higher probe tones significantly correlated with comfort levels. Conclusion The ESRT with higher probe tones was correlated with behavioral comfort levels and increased the success rate of the measurements. Higher-frequency probe tones may be useful whenever ESRT with 226 Hz is not measurable.
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OBJECTIVE To investigate the characteristics and laws of changes in electrically evoked auditory brainstem responses(EABR),electrically evoked stapedius reflex(ESRT) after cochlear implantation in children with inner ear malformation.METHODS 88 cases of Australian 24 multi-channel cochlear implants were divided into normal group and inner ear malformation group,The EABR and ESRT thresholds were measured at different periods within one year after operation.Behavior auditory responses,T-level and C-level were measured 1 year postoperatively to analyze their characteristics and changes.RESULTS The EABR and ESRT thresholds in the patients with inner ear malformation were significantly higher than those in the normal cochlear group(P＜0.05).The changing trend of EABR and ESRT were the same in the 2 groups,the overall trend is that low frequency value is low,high frequency value is higher.EABR,ESRT threshold increased gradually after 1 year,EABR was significantly correlated with T-level,and ESRT was significantly correlated with C-level.CONCLUSION The changes of EABR and ESRT thresholds in the cochlear implantation of the inner ear malformation group were similar to those of the normal cochlear group,the thresholds can be used to guide mapping for the inner ear malformation of the cochlear implant.
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Objective To analyze the medical and audiological features of trauma induced stapes fracture ,and to summarize the key diagnostic points and to observe the effects of surgical treatment .Methods Five patients with trauma induced stapes fracture confirmed by the surgical exploration from January 1995 to October 2013 were retro_spectively reviewed .Ossicular chain reconstruction was performed on each patient .The preoperative and postopera_tive pure-tone thresholds were compared to judge the effects of surgical treatment .ResuIts The surgical explora_tion revealed 4 cases of stapes feet fracture ,1 case of stapes neck fracture with temporal bone fracture and peripheral paralysis of the facial nerve .Different types of ossicular reconstruction were performed according to the exploration results:2 cases with autogenous stapes remodeling ,1 case with allogenous stapes remodeling ,1 case with bone piece of external acoustic meatus ,and 1 case with artificial auditory ossicle(TORP) implanting .Additionally ,the case of peripheral paralysis of the facial nerve received facial nerve decompression .After the operation ,5 patients felt that their hearing was improved .The mean postoperative pure-tone threshold was 30 .7 dB HL ,and the mean ABG(air-bone-gap) was 18 dB HL while the mean preoperative pure-tone threshold was 61 dB HL(t=6 .725 ,P<0 .05) and the mean ABG was 38 .7 dB HL(t=3 .616 ,P<0 .05) .The facial nerve functions of the case with facial paralysis recovered to House-Brackmann Grade I three months after receiving facial nerve decompression .ConcIu_sion Stapes fractures are rare .Being different from the general conductive hearing loss ,patients with stapes fracture usu_ally have the acoustic stapedius reflex .Through ossicular reconstruction ,we can yield a satisfying hearing recovery .
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Objective Using maestro software to analyze the application of electrically elicited stapedius reflex and auditory nerve response in assessing acoustic function intraoperatively .Methods 20 SONATATI100cochlear im-plant patients participated in this study .Both ESRT and ECAP were recorded intraoperatively by using MED -EL Maestro software and analyzed .Results 96 .67% typical ESR and 95 .0% typical ECAP were recorded .Certain properties of ECAP recordings varied depending on the stimulation sites in the cochlea .There was strong relation-ship between ESRT and ECAP thresholds .Conclusion ESR and ART were proved to be most beneficial in assessing the functions of the implanted as well as proving that the auditory pathway is stimulated during the cochlear implan-tation surgery .
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@#Objective To investigate the adjustment methods and evaluation for children after cochlear implantation. Methods 6 children after artificial cochlear implantation were debugged by subjective psychological physical test, objective methods such as electricity induced composite action potential (ECAP), electrically evoked stapedius reflex threshold (ESRT) and electrically evoked auditory brainstem response (EABR). Results All the children got satisfied data. Conclusion For the children after cochlear implantation, objective methods such as ECAP, ESRT, EABR combined with subjective psychological physical test all together are helpful to obtain accurate threshold.
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Objective To investigate the effects of different intensity of wide band noise on acoustic stapedius reflex amplitude in sound field. Methods Acoustical reflex amplitude(at ART+10 dB)were obtained at three fre-quencies (1,2, 4 kHz) from 80 normally hearing subjects with wide band noise at 30,40,50 and 60 dB SL in sound field. Results Acoustical reflex amplitude was significantly decreased in the presence of wide band noise (P 0. 01). The most significant decrease of acoustic reflex amplitude could be observed in the present of 40 dB SL wide band noise. In comparison with the 1 kHz group, significant decrease was found in 2 kHz group and 4 kHz group(P <0. 01),but there was no difference between the 2 kHz group and 4 kHz group(P>0.05). Conclusion Since the decrease of the acoustic stapedius reflex amplitude is mediated by the auditory efferent system in sound field, in clini-cal practice the function of the auditory efferents can be evaluated by testing the change of acoustic stapedius reflex amplitude with the stimulation of the wide band noise in sound field.
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Objective To study the effects of multi frequency tympanometry and acoustic stapedius reflexes on the diagnosis of the middle ear functions of infants.Methods Tympanometries with 226,678 and 1 000 Hz probe tones and 500 and 1 000 Hz acoustic stapedius reflexes were performed on infants at age 0~1 year.128 normal infants(256 ears) and 104 abnormal infants(168 ears) were tested with GSI Tympstar middle ear analyzer.Results The patterns of 226 Hz tympanograms were non-peaked,single-peaked and W-shaped.There were no significant differences between two groups of infants aged 0～6 months.The patterns of 678 Hz and 1 000 Hz tympanograms showed significant differences between two groups of infants aged 0～1 year.The outcomes of 500 Hz and 1 000 Hz acoustic stapedius reflexes showed no differences between the same age groups.There were significant differences between normal group and abnormal group.Conclusion Tympanometry with 678 Hz and 1 000 Hz probe tones can yield accurate diagnostic results in the assessment of the middle ear functions for infants younger than six months.The tympanometry with three frequency probe tones is sensitive to infants aged 6～12 months.The outcomes of acoustic stapedius reflexes at 500 and 1 000 Hz show no differences between the same age groups,but presences become more noticeable as a function of ages.
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BACKGROUND AND OBJECTIVES: An essential part of the successful application of a cochlear implant is to adjust the stimulation levels to the patient's dynamic range. To test the subjective behavioral threshold (T-level) and the most comfortable loudness level (C-level), however, it may be troublesome or even impossible in very young children who are not able to perform such tasks appropriately. Therefore, utilization of objective measurements is important in children to estimate T- and C-levels. One of the objective measurements is the electrically evoked stapedial reflex (ESR) test. It has also been suggested that ESR may have applicability in confirming and quantifying electrical stimulation through a cochlear implant. The purpose of this study is to examine the feasibility of utilizing ESR to test device function during cochlear implant surgery and to predict ultimate behavioral T- & C-levels. MATERIALS AND METHODS: The ESR measurements were performed in 18 subjects during a cochlear implant surgery. Eight subjects received the Nucleus 22 multichannel cochlear implant (CI 22M) and 10 subjects received Nucleus 24 multichannel cochlear implant system (CI 24M). To test the ESRs, three electrodes, namely, apical electrode (E20), medial electrode (E12) and basal electrode (E5), were stimulated in each case. ESR thresholds were measured by visual observation of the stapedius muscle contraction in response to electrical stimulation delivered to the auditory nerve via a cochlear implant system. And the ESR thresholds were compared with the behavioral T- and C-levels in each electrode. RESULTS: ESRs were presented in 19/23 electrodes (82.6%) in subjects who received the CI 22M and 26/30 electrodes (86.7%) in subjects with CI 24M. The mean ESR threshold was the lowest in apical electrodes (E20) in both groups. In subjects with CI 22M, ESR thresholds were significantly correlated with behavioral T- and C-levels in apical electrodes (E20). In subjects with CI 24M, ESR thresholds were highly correlated with the C-levels in E5, E12, and E20. CONCLUSION: ESR provides an objective, accurate and rapid method to evaluate the device function during cochlear implant surgeries and in estimating T-/C- levels, which may be useful in the initial programming of younger children and the difficult-to-tests.