A commonly used anesthetic, isoflurane, can impair auditory function in a dose-dependent manner. However, in rats, isoflurane-induced auditory impairments have only been assessed with auditory brainstem responses; a m...A commonly used anesthetic, isoflurane, can impair auditory function in a dose-dependent manner. However, in rats, isoflurane-induced auditory impairments have only been assessed with auditory brainstem responses; a measure which is unable to distinguish if changes originate from the central or peripheral auditory system. Studies performed in other species, such as mice and guinea-pigs, suggests auditory impairment stems from disrupted OHC amplification. Despite the wide use of the rat in auditory research, these observations have yet to be replicated in the rat animal model. This study used distortion product otoacoustic emissions to assess outer hair cell function in rats that were anesthetized with either isoflurane or a ketamine/xylazine cocktail for approximately 45 min. Results indicate that isoflurane can significantly reduce DPOAE amplitudes compared to ketamine/xylazine, and that responses were more variable with isoflurane than ketamine/xylazine over the 45-min test period. Based on these observations, isoflurane should be used with caution when assessing peripheral auditory function to avoid potentially confounding effects.展开更多
Objectives To investigate changes in evoked potentials and structure of the guinea pig cochleae during whole cochlear perfusion with glutamate. Methods CM, CAP, DPOAE, and ABR were recorded as indicators of cochlear f...Objectives To investigate changes in evoked potentials and structure of the guinea pig cochleae during whole cochlear perfusion with glutamate. Methods CM, CAP, DPOAE, and ABR were recorded as indicators of cochlear functions during whole cochlear perfusion. The morphology of the cochlea was studied via transmission electron microscopy. Results There were no significant changes in DPOAE amplitude before and after glutamate perfusion. CM I/O function remained nonlinear during perfusion. ABR latencies were delayed following glutamate perfusion. The average CAP threshold was elevated 35 dB SPL following glutamate perfusion.. The OHCs appeared normal, but the IHCs and afferent dendrites showed cytoplasmic blebs after glutamate perfusion. Conclusions While being a primary amino acid neurotransmitter at the synapses between hair cells and spiral ganglion neurons, excessive glutamate is neurotoxic and can destroy IHCs and spiral ganglion neurons. The technique used in this study can also be used to build an animal model of auditory neuropathy.展开更多
Background:Studies on animals have demonstrated that maternal iron deficiency anaemia(IDA)could result in decreased cochlear sensory hair cells and reduced amplitudes of distortion-product otoacoustic emissions(DPOAEs...Background:Studies on animals have demonstrated that maternal iron deficiency anaemia(IDA)could result in decreased cochlear sensory hair cells and reduced amplitudes of distortion-product otoacoustic emissions(DPOAEs)of young guinea pigs.Thus,it is essential to study the functioning of cochlear hair cells using DPOAEs in human newborn babies with maternal IDA.The current study explores maternal IDA’s effect on DPOAEs in newborn babies.Method:A total of 110 newborn babies with gestational age≥34 weeks were considered and a‘betweensubjects’design was used.The participants were divided into 3 groups-“Normal”(61 babies without maternal IDA),“Mild”(28 babies with mild maternal IDA)and“Moderate”(21 babies with moderate maternal IDA).The cord blood was collected and the DPOAEs were recorded for each baby for a range of frequencies(1 k 8 kHz)and a range of intensities(7040 dB SPL in 10 dB steps).Results:The analysis of both DP-gram and DP input-output(I/O)function showed that there was no significant difference(p>0.05)across the normal,mild,and moderate groups in the overall presence of DPOAEs as well as the amplitude across frequencies or intensities(7040 dB SPL).Also,the overall correlation of RBC indices with DPOAE amplitude across frequencies as well as the slope of the I/O function showed no relationship.Conclusion:The current study concludes that there is no effect of late-term maternal IDA on the DPOAEs of newborn babies.展开更多
Objectives:This study aimed to determine the prognostic value of otoacoustic emissions(OAEs)in idiopathic sudden sensorineural hearing loss patients.Methods:The study included 30 subjects with unilateral idiopathic su...Objectives:This study aimed to determine the prognostic value of otoacoustic emissions(OAEs)in idiopathic sudden sensorineural hearing loss patients.Methods:The study included 30 subjects with unilateral idiopathic sudden sensorineural hearing loss(ISSNHL).Each patient was evaluated four times:at baseline and after one week,one month,and three months of treatment.During each visit,each patient was subjected to full audiological history,otoscopic examination,basic audiological evaluations,and transiently evoked and distortion product otoacoustic emission(TEOAEs&DEOAEs).Results:The hearing thresholds(frequency range 250e8000 Hz)and word recognition scores of patients with detectable TEOAEs and DPOAEs improved significantly,whereas no significant improvements were observed in those with no response.Conclusion:Hearing improvement is better in patients with detectable TEOAEs and DPOAEs.As a result,TEOAEs and DPOAEs are recommended as routine tests in all SSNHL patients to predict outcomes and monitor treatment as TEOAEs and DPOAEs reflect the cochlear OHCs activity.展开更多
目的应用畸变产物耳声发射(DPOAE)对窒息新生儿与正常新生儿进行听力筛查,比较其听力损失的发生率。方法使用MAICO ERO SCAN新生儿筛查型耳声发射仪对195例窒息新生儿和3002例正常新生儿进行DPOAE听力筛查。根据1分钟Apgar评分,将195例...目的应用畸变产物耳声发射(DPOAE)对窒息新生儿与正常新生儿进行听力筛查,比较其听力损失的发生率。方法使用MAICO ERO SCAN新生儿筛查型耳声发射仪对195例窒息新生儿和3002例正常新生儿进行DPOAE听力筛查。根据1分钟Apgar评分,将195例窒息新生儿分为轻度(177例)和重度(18例)窒息。窒息新生儿初筛在病情稳定后进行,正常新生儿在出生后1～5天进行,窒息新生儿通过及未通过者均于出生后1、3、6、12个月分别再测试,监测有无迟发性耳聋的发生;正常新生儿未通过者在出生后42天进行复筛,两组两次检测仍未通过者在出生后3个月时用听性脑干反应(ABR)、40Hz-AERP和声导抗进行诊断性听力评估。采用SPSS10.0软件进行统计学分析。结果 195例窒息新生儿,初筛通过148例,初筛通过率为75.90%(148/195),未通过47例,未通过率为24.10%(47/195);3002例正常新生儿,初筛通过2504例,初筛通过率为86.41%(2504/3002),正常新生儿初筛通过率显著高于窒息新生儿(P<0.01)。轻度窒息新生儿177例,初筛通过138例,初筛通过率77.97%(138/177),重度窒息新生儿18例,初筛通过10例,初筛通过率55.56%(10/18),轻度窒息新生儿初筛通过率高于重度窒息新生儿(P<0.05)。窒息新生儿复筛通过率为92.59%(25/27),正常新生儿复筛通过率为97.49%,两者差异无统计学意义(χ2=0.916,P>0.05)。确诊窒息新生儿听力损伤1例,听力损失检出率5.13‰(1/195);正常新生儿听力损失6例,听力损伤检出率为2.00‰(6/3002),两者差异无统计学意义(χ2=0.574,P>0.05)。结论正常新生儿听力初筛通过率显著高于窒息新生儿,复筛通过率两组无差异,窒息新生儿与正常新生儿听力损失检出率无显著性差异,DPOAE可作为窒息新生儿与正常新生儿听力筛查的一种有效方法。展开更多
基金Research supported in part by grants from the National Institutes of Health to AS (F31DC015933) and RS (R01DC014452)the American Academy of Audiology to ASthe China Scholarship Council (No.201606095027) to DL
文摘A commonly used anesthetic, isoflurane, can impair auditory function in a dose-dependent manner. However, in rats, isoflurane-induced auditory impairments have only been assessed with auditory brainstem responses; a measure which is unable to distinguish if changes originate from the central or peripheral auditory system. Studies performed in other species, such as mice and guinea-pigs, suggests auditory impairment stems from disrupted OHC amplification. Despite the wide use of the rat in auditory research, these observations have yet to be replicated in the rat animal model. This study used distortion product otoacoustic emissions to assess outer hair cell function in rats that were anesthetized with either isoflurane or a ketamine/xylazine cocktail for approximately 45 min. Results indicate that isoflurane can significantly reduce DPOAE amplitudes compared to ketamine/xylazine, and that responses were more variable with isoflurane than ketamine/xylazine over the 45-min test period. Based on these observations, isoflurane should be used with caution when assessing peripheral auditory function to avoid potentially confounding effects.
文摘Objectives To investigate changes in evoked potentials and structure of the guinea pig cochleae during whole cochlear perfusion with glutamate. Methods CM, CAP, DPOAE, and ABR were recorded as indicators of cochlear functions during whole cochlear perfusion. The morphology of the cochlea was studied via transmission electron microscopy. Results There were no significant changes in DPOAE amplitude before and after glutamate perfusion. CM I/O function remained nonlinear during perfusion. ABR latencies were delayed following glutamate perfusion. The average CAP threshold was elevated 35 dB SPL following glutamate perfusion.. The OHCs appeared normal, but the IHCs and afferent dendrites showed cytoplasmic blebs after glutamate perfusion. Conclusions While being a primary amino acid neurotransmitter at the synapses between hair cells and spiral ganglion neurons, excessive glutamate is neurotoxic and can destroy IHCs and spiral ganglion neurons. The technique used in this study can also be used to build an animal model of auditory neuropathy.
文摘Background:Studies on animals have demonstrated that maternal iron deficiency anaemia(IDA)could result in decreased cochlear sensory hair cells and reduced amplitudes of distortion-product otoacoustic emissions(DPOAEs)of young guinea pigs.Thus,it is essential to study the functioning of cochlear hair cells using DPOAEs in human newborn babies with maternal IDA.The current study explores maternal IDA’s effect on DPOAEs in newborn babies.Method:A total of 110 newborn babies with gestational age≥34 weeks were considered and a‘betweensubjects’design was used.The participants were divided into 3 groups-“Normal”(61 babies without maternal IDA),“Mild”(28 babies with mild maternal IDA)and“Moderate”(21 babies with moderate maternal IDA).The cord blood was collected and the DPOAEs were recorded for each baby for a range of frequencies(1 k 8 kHz)and a range of intensities(7040 dB SPL in 10 dB steps).Results:The analysis of both DP-gram and DP input-output(I/O)function showed that there was no significant difference(p>0.05)across the normal,mild,and moderate groups in the overall presence of DPOAEs as well as the amplitude across frequencies or intensities(7040 dB SPL).Also,the overall correlation of RBC indices with DPOAE amplitude across frequencies as well as the slope of the I/O function showed no relationship.Conclusion:The current study concludes that there is no effect of late-term maternal IDA on the DPOAEs of newborn babies.
文摘Objectives:This study aimed to determine the prognostic value of otoacoustic emissions(OAEs)in idiopathic sudden sensorineural hearing loss patients.Methods:The study included 30 subjects with unilateral idiopathic sudden sensorineural hearing loss(ISSNHL).Each patient was evaluated four times:at baseline and after one week,one month,and three months of treatment.During each visit,each patient was subjected to full audiological history,otoscopic examination,basic audiological evaluations,and transiently evoked and distortion product otoacoustic emission(TEOAEs&DEOAEs).Results:The hearing thresholds(frequency range 250e8000 Hz)and word recognition scores of patients with detectable TEOAEs and DPOAEs improved significantly,whereas no significant improvements were observed in those with no response.Conclusion:Hearing improvement is better in patients with detectable TEOAEs and DPOAEs.As a result,TEOAEs and DPOAEs are recommended as routine tests in all SSNHL patients to predict outcomes and monitor treatment as TEOAEs and DPOAEs reflect the cochlear OHCs activity.
文摘目的应用畸变产物耳声发射(DPOAE)对窒息新生儿与正常新生儿进行听力筛查,比较其听力损失的发生率。方法使用MAICO ERO SCAN新生儿筛查型耳声发射仪对195例窒息新生儿和3002例正常新生儿进行DPOAE听力筛查。根据1分钟Apgar评分,将195例窒息新生儿分为轻度(177例)和重度(18例)窒息。窒息新生儿初筛在病情稳定后进行,正常新生儿在出生后1～5天进行,窒息新生儿通过及未通过者均于出生后1、3、6、12个月分别再测试,监测有无迟发性耳聋的发生;正常新生儿未通过者在出生后42天进行复筛,两组两次检测仍未通过者在出生后3个月时用听性脑干反应(ABR)、40Hz-AERP和声导抗进行诊断性听力评估。采用SPSS10.0软件进行统计学分析。结果 195例窒息新生儿,初筛通过148例,初筛通过率为75.90%(148/195),未通过47例,未通过率为24.10%(47/195);3002例正常新生儿,初筛通过2504例,初筛通过率为86.41%(2504/3002),正常新生儿初筛通过率显著高于窒息新生儿(P<0.01)。轻度窒息新生儿177例,初筛通过138例,初筛通过率77.97%(138/177),重度窒息新生儿18例,初筛通过10例,初筛通过率55.56%(10/18),轻度窒息新生儿初筛通过率高于重度窒息新生儿(P<0.05)。窒息新生儿复筛通过率为92.59%(25/27),正常新生儿复筛通过率为97.49%,两者差异无统计学意义(χ2=0.916,P>0.05)。确诊窒息新生儿听力损伤1例,听力损失检出率5.13‰(1/195);正常新生儿听力损失6例,听力损伤检出率为2.00‰(6/3002),两者差异无统计学意义(χ2=0.574,P>0.05)。结论正常新生儿听力初筛通过率显著高于窒息新生儿,复筛通过率两组无差异,窒息新生儿与正常新生儿听力损失检出率无显著性差异,DPOAE可作为窒息新生儿与正常新生儿听力筛查的一种有效方法。
