特发性突聋的听力学定位诊断研究

本文采用阈上听力测验、耳蜗电图、听性脑干反应技术对特发性突聋47例（52耳）进行听力学定位诊断研究。结果表明：耳蜗性病变30耳（57.69%)，蜗后病变20耳（38．46％），耳蜗及蜗后联合病变2耳（3.85%)。眩晕、听力障碍、听力图形、发病情况与病变部位无明显关系；伴否耳鸣及耳鸣音调高低与病变部位无明显关系，但如耳鸣为多种声音混杂者则蜗后病变可能性极大。听力损失较重者蜗后病变所占比例较高。阈上听力测验中音衰变试验（TDT）可靠性较高，而ABLB、SISI准确率低，实用价值不大，蜗后病变预后较差。     

纯音骨导听阈测试的掩蔽问题

目的：通过对一组耳科正常青年人及不同性质的耳聋患者进行韦伯试验(WT)及骨导掩蔽测试，以探讨骨导测试现象的规律，为临床测试提供指导。方法：分别对20例耳科正常青年人及113例有不同性质听力损失的患者进行WT及骨导掩蔽测试。结果：当双耳均无传导障碍时，骨导听阈取决于双耳耳蜗听敏度，WT偏向取决于双耳听敏度之差。不同性质的传导性病变，使不同频段的骨导听阈降低。一耳正常，另耳为传导性聋时，WT3～5个频率偏患耳；另耳为耳蜗性聋且气导耳间差大于40dB时，患耳骨导越边。双耳传导性聋或双耳混合性聋或一耳传导性聋另耳混合性聋，骨导听阈取决于双耳病变的不同性质、不同程度，WT偏向无规律。当双耳骨导听阈正常而气导听阈大于耳间衰减时，则掩蔽无法实施。结论：为避免中枢掩蔽和过度掩蔽的影响，实验发现：①双耳均无传导障碍，且双耳气导听阈之差大于40dB，测优势耳骨导时不需掩蔽，劣势耳骨导听阈越边；②一耳正常、另耳为传导性聋，测试患耳骨导时不需掩蔽；③若双耳存在传导性病变，且骨导听阈正常而气导听阈大于耳间衰减，则掩蔽无法实施，放弃掩蔽测试。     

感音神经性聋的诊断和治疗

感音神经性聋概述 由于耳蜗毛细胞、听神经、听觉通路或各级听中枢神经元受损害,致声音的感受与神经冲动传递障碍者,称感音性聋或神经性聋.其中毛细胞病变引起者称感音性聋(耳蜗性聋或终器性聋),病变位于听神经及听觉通路者称神经性聋(蜗后性聋),病变发生于听觉中枢核团或大脑皮层听中枢者称中枢性聋.     

人工耳蜗植入前、后中耳炎性病变的处理--附6例报告

目的总结人工耳蜗植入前中耳炎性病变,以及植入后中耳、内耳感染的治疗经验.方法术前2例分泌性中耳炎伴乳突粘膜病变和1例慢性中耳炎选择一期手术;1例中耳乳突炎,1例胆脂瘤行分期手术.5例患者耳后切口经面神经隐窝入路植入电极,1例乳突根治术后术中借卵圆窗和鼓岬定位耳蜗钻孔部位植入电极,术中均进行电极阻抗测试和听神经遥测反应测试.结果1例术后中耳炎伴迷路炎经保守治疗痊愈.所有患者植入耳蜗工作正常,随访10-40月未见与中耳炎相关的并发症.结论极重度感音神经性聋伴分泌性中耳炎患者,原则上应分期手术;合并中耳乳突炎者,也应分期手术,完壁式和经典式乳突根治,根据病情均可选用.但中耳炎静止期鼓膜小穿孔者,可考虑一期手术.     

突发性聋的病理学改变

突聋的发病原因至今不明,有内耳血管病变说,迷路窗膜破裂说和病毒感染说。作者报告了自1962年至1985年间12例生前曾患突聋病人的颞骨切片所见。根据耳蜗组织学改变,讨论了突聋的病因学。 12块颞骨,单侧病变10例,双侧病变1例。男性7人,女性4人。发病年龄25～68岁,平均52.3岁。左侧及右侧病变各6耳。单纯耳蜗症状者10例,伴明显眩晕者2例。极重度聋9例,重度聋2例,中度聋1例。11例为永久性聋,仅1例患者的听力于发病后     

中枢掩蔽与耳声发射对侧抑制相关性研究

目的：探讨中枢掩蔽与耳发射对侧抑制的相关性。方法：通过对一组耳科正常青年人及4例蜗后聋患者同时进行相同条件下中枢掩蔽及耳声发射对侧抑制的测试，观察中枢掩蔽与耳声发射对侧抑制在同一实验对象的表现。结果：在正常人组中，当对侧掩蔽声小于60 d BHL时，中枢掩蔽效应及耳声发射的对侧抑制均随对侧掩蔽声增加而增大，掩蔽强度大于60 d BHL时，则出现过度掩蔽。耳声发射记录过程中，本底噪声明显升高。当对侧掩蔽声固定为60 d BHL时，中频1.0、2.0kHz中枢掩蔽效应及耳声发射对侧抑制明显高于低频及高频，2.0kHz处最为明显；在蜗后聋组中，健耳或听力损伤较轻耳，中枢掩蔽及耳声发射对侧抑制接近正常人耳，而患者或听力损失较重耳，中枢掩蔽效应为负值或零，对侧抑制表现为反抑制或不抑制。结论：中枢掩蔽与对侧抑制存在相同的发生机理，表现出相同的频率特异性及强度特异性，无论在正常人耳还是病变耳，均表现出高度的相关性。     

听神经瘤致聋机理—14例（16耳）听神经瘤病人听力测试结果分析

目的：探讨听神经瘤听力损失的病理生理机制。方法：对14例（16耳）听神经瘤患者行纯音听阈、阻抗、听性脑干反应（ABR）、诱发耳声发射测试（EOAE）及CT和（或）MRI扫描。EOAE能引出的4耳还检测其传出抑制功能，ABR不能检测且EOAE不能引出的重度聋（听力损失大于80dB)有5耳行鼓岬刺激试验（PST）。结果：16耳听神经瘤中2耳（12．50％）听力损失源于神经性损害；6耳（37．50％）蜗性损害；8耳（50％）蜗－神经性损害。能引出EOAE的4耳均有传出功能障碍。结论：EOAE可评价听神经瘤的耳蜗功能形态；ABR结合PST能分析听神经瘤的蜗后神经功能。听神经瘤的听觉病理可同时或单独发生于听外周的耳蜗水平、第Ⅷ对颅神经（传入神经）水平和橄榄核耳蜗传出神经水平。     

外伤性鼓膜穿孔和单纯慢性化脓性中耳炎鼓膜成形术的疗效比较

目的回顾性分析外伤性鼓膜穿孔与单纯型慢性化脓性中耳炎的鼓膜成形术后愈合率及手术前后的听力变化。方法 2008年7月~2011年7月于我科接受首次手术治疗的住院患者,外伤性鼓膜穿孔组19例(20耳),单纯型慢性化脓性中耳炎54例(55耳)。术前及术后三个月随访使用电子耳镜检查鼓膜像,听力评估以500Hz、1000Hz、2000Hz和4000Hz的气骨导差(AirBoneGap,ABG)平均数x-±s表示。结果外伤性鼓膜穿孔的手术愈合率是70.00%(14/20)。单纯型慢性化脓性中耳炎手术愈合率为92.73%(51/55),连续校正的X2=4.74,P<0.05;鼓膜愈合率与年龄、手术方式(外置或内置)以及穿孔大小未见明显相关性。外伤性鼓膜穿孔患者术前平均ABG为17.25±5.81dBHL,单纯型慢性化脓性中耳炎患者术前平均ABG为23.34±9.53dB,两组术前平均听力比较t=2.68,p=0.003。外伤性鼓膜愈合的14例术前平均ABG为17.85±6.15dB,术后为10.58±5.99dB,p=0.005;单纯型慢性化脓性中耳炎组51例鼓膜愈合术前ABG为23.35±9.76dB,术后为14.28±10.53dB,p=0.001,两组术后听力较术前均有明显提高。结论外伤性鼓膜穿孔手术修补成功率较慢性化脓性中耳炎为低。多数外伤性鼓膜穿孔的听力损失较单纯型慢性化脓性中耳炎要轻,而手术成功率更低,需要耳科医生在术前谈话中注意交代手术风险与收益。     

庆大霉素治疗非梅尼埃病的外周性前庭疾病

鼓室内注射庆大霉素治疗严重的梅尼埃病耗资少，方法简便；其原理为药物性迷路切除，主要副作用是听力损失加重。该文作者试用这种方法治疗非梅尼埃病的外周性前庭疾病患者5例，获得了满意效果。5例患者中，年龄最小15岁，最大78岁，男3例，女2例。其中3例分别有一侧原因不明的先天性感音神经性聋，流行性腮腺炎性脑炎后全聋及突发性耳聋病史，以后出现眩晕，每次发作持续数秒、数分钟至几小时不等，无耳鸣，l例伴呕吐，发作史5个月至5年；另2例中，1例为外伤性鼓膜穿孔愈后出现良性阵发性水平性眩晕伴一侧突发性耳聋已2年，l例为老年听神经…     

中耳炎性病变患者的人工耳蜗植入

目的探讨伴中耳炎性病变的患者进行人工耳蜗植入的适应证、手术方法和术后并发症的发生情况。方法对1995年5月至2006年2月完成的866例人工耳蜗植入术的临床资料进行回顾性分析。术前或术中发现伴中耳乳突炎性病变患者共41例，其中男17例，女24例，年龄1岁3个月-38岁，平均10岁2个月；左耳人工耳蜗植入18例，右耳植入23例，均为单侧植入。其中慢性分泌性中耳炎13例，隐蔽性中耳炎18例，中耳炎后遗症鼓膜穿孔1例，双侧胆脂瘤中耳炎2例，中耳乳突肉芽肿7例。中耳炎性病变伴内耳、中耳畸形7例。对于双侧胆脂瘤中耳炎乳突根治术后患者，设计采用了带蒂翻转帽状腱膜法保护植入电极和面神经。结果41例患者经 Ⅰ期或分期手术，术后随访时间5个月至6年11个月，平均未发现耳部炎性并发症，装置工作良好。结论慢性非化脓性中耳炎、中耳乳突肉芽肿、中耳炎后遗症伴鼓膜穿孔者可采用Ⅰ期或分期方法行人工耳蜗植入。胆脂瘤中耳炎在彻底去除病变基础上可分期行人工耳蜗植入术。对于乳突根治术后没有足够组织覆盖保护植入电极的病例，可采用带蒂翻转帽状腱膜方法。存在活动性中耳乳突炎症者为手术禁忌证。中耳炎性病变患者人工耳蜗术后应长期随访。     

正常人中枢掩蔽测试结果分析

目的 :通过对一组耳科正常青年人进行中枢掩蔽测试 ,探讨其发生机制及其对听力学检查所产生的影响。方法 :分别测试有无对侧掩蔽声 (CAS)时的纯音气导听阈 ,比较其在相同频率不同强度的CAS时听阈的变化 ,即中枢掩蔽效应 (CME)的大小 ;同时测试相同强度不同频率CAS时CME的大小。结果 :CME具有频率特异性及强度特异性 ,中频 1kHz、2kHz时 ,其CME较低频及高频大 ,其中以频率为 2kHz时最明显 ;CAS强度在6 0dBHL以下时 ,CME随强度增加而增大 ,在 6 0dBHL时 ,2kHz处CME达 (11.5 3± 4 .38)dB ,CAS >70dBHL时 ,则出现过度掩蔽。结论 :因CME的存在 ,纯音听阈测试中 ,如所用CAS >4 0dBHL时 ,则需对测试结果进行修正 ;当CAS强度为 6 0dBHL时 ,CAS在 2kHz处产生大于 10dB的CME ,可用于对伪聋的鉴别     

Contralateral masking in cochlear implant users with residual hearing in the non-implanted ear

Contralateral masking was investigated in cochlear implant users with residual hearing in the non-implanted ear. Threshold elevations for acoustic probes were observed when electrical maskers were presented in the opposite ear. Also, threshold elevations for electrical probes were observed when acoustic contralateral maskers were presented. The amount of threshold shift expressed in decibels charge or decibels sound pressure level produced by either contralateral acoustic or electric maskers was within the range found in normal listeners for similar stimuli (i.e. 4-8 dB). There was a correlation between the sensation level of acoustic maskers and the maximum amount of masking observed which is consistent with data for normally hearing subjects. The width of the masking patterns was similar to that expected from forward masking patterns in severely sensorineurally impaired ears and implanted ears. The maximum amount of acoustic masking tended to occur for electrode positions that were more basal than expected from characteristic frequency positions. However, where a relatively high-frequency 4-kHz masker could be used, there was a good match between the characteristic frequency position of the maximum threshold elevation and that of the masker.     

High-level psychophysical tuning curves: forward masking in normal-hearing and hearing-impaired listeners.

Forward-masked psychophysical tuning curves (PTCs) were obtained for 1000-Hz probe tones at multiple probe levels from one ear of 26 normal-hearing listeners and from 24 ears of 21 hearing-impaired listeners with cochlear hearing loss. Comparisons between normal-hearing and hearing-impaired PTCs were made at equivalent masker levels near the tips of PTCs. Comparisons were also made of PTC characteristics obtained by fitting each PTC with three straight-line segments using least-squares fitting procedures. Abnormal frequency resolution was revealed only as abnormal downward spread of masking. The low-frequency slopes of PTCs from hearing-impaired listeners were not different from those of normal-hearing listeners. That is, hearing-impaired listeners did not demonstrate abnormal upward spread of masking when equivalent masker levels were compared. Ten hearing-impaired ears demonstrated abnormally broad PTCs, due exclusively to reduced high-frequency slopes in their PTCs. This abnormal downward spread of masking was observed only in listeners with hearing losses greater than 40 dB HL. From these results, it would appear that some, but not all, cochlear hearing losses greater than 40 dB HL influence the sharp tuning capabilities usually associated with outer hair cell function.     

Informational masking in normal-hearing and hearing-impaired listeners

The present study aimed to test whether central, across-channel, informational auditory processing abilities are altered by hearing loss. The informational masking effect exerted on a 1 kHz tone-pip by a simultaneous four-tone masker, whose spectral content changed within as well as across trials, was measured in the left and right ears of normal-hearing subjects and hearing-impaired subjects with either symmetrical or asymmetrical hearing loss between the two ears. In the subjects with normal-hearing or symmetrical hearing loss, the level of the masker was set to 40 dB SL in each ear, in the subjects with asymmetrical hearing loss, the masker was set to 40 dB SL in the best ear and loudness-balanced in the other ear. The results failed to reveal significant differences in informational masking between normal-hearing and hearing-impaired subjects. However, in subjects with asymmetric hearing loss, less informational masking was observed in the ear with the more elevated absolute thresholds than in the opposite ear. Since the latter finding can be explained in terms of across-ear differences in loudness recruitment, it is suggested that central, across-channel, informational processing abilities are not substantially different in hearing-impaired than in normal-hearing ears.     

Acoustic reflex thresholds in normal and cochlear-impaired ears: effects of no-response rates on 90th percentiles in a large sample

Ninetieth percentile cutoffs for acoustic reflex thresholds (ARTs) were determined for a sample of 2,748 ears of 1,374 subjects with normal hearing and sensorineural loss of cochlear origin. All subjects had measurable hearing (less than or equal to 110 dB HL, ANSI-1969) at all three activator frequencies (500, 1000, and 2000 Hz). Cutoff values including "no responses" ("absent" reflexes at 125 dB HL) were higher than those excluding no responses when hearing losses were greater than about 55 dB. The 90th percentiles including the effects of no responses identified ears with retrocochlear involvement for hearing losses as great as about 756 dB. For greater hearing losses at the activator frequency, the no-response rate for both cochlear and retrocochlear cases is too high to enable them to be differentiated by acoustic reflex thresholds. The 90th percentiles are derived at each activator frequency collapsed across ears. It is therefore necessary to determine the probabilities that normal or cochlear-impaired ears will have one, two, or three frequencies at which the ARTs exceed their respective 90th percentiles. It was found that among normal and cochlear-impaired ears, 12.2% have one ART elevated above the 90th percentile, but only 5.6% have two or three elevated ARTs. Clinical implications are discussed.     

Informational Masking in Normal-hearing and Hearing-impaired Listeners

The present study aimed to test whether central, across-channel, informational auditory processing abilities are altered by hearing loss. The informational masking effect exerted on a 1 kHz tone-pip by a simultaneous four-tone masker, whose spectral content changed within as well as across trials, was measured in the left and right ears of normal-hearing subjects and hearing-impaired subjects with either symmetrical or asymmetrical hearing loss between the two ears. In the subjects with normal-hearing or symmetrical hearing loss, the level of the masker was set to 40 dB SL in each ear, in the subjects with asymmetrical hearing loss, the masker was set to 40 dB SL in the best ear and loudness-balanced in the other ear. The results failed to reveal significant differences in informational masking between normal-hearing and hearing-impaired subjects. However, in subjects with asymmetric hearing loss, less informational masking was observed in the ear with the more elevated absolute thresholds than in the opposite ear. Since the latter finding can be explained in terms of across-ear differences in loudness recruitment, it is suggested that central, across-channel, informational processing abilities are not substantially different in hearing-impaired than in normal-hearing ears.     

Evoked otoacoustic emissions in sensorineural hearing impairment: its clinical implications

This study was performed for the purpose of determining whether or not evoked otoacoustic emissions are useful as a clinical test. Two hundred and twenty-six sequences of the emission in response to stimulus tone bursts were averaged. The detection threshold of the emission was elevated in ears of inner ear impairment with profound sensorineural hearing loss, such as inner ear anomaly, mumps deafness, or sudden deafness, but it was not observed in ears of functional deafness. The mean interaural differences of emission threshold were near 35 dB in unilateral inner ear impairments with profound hearing loss. There was a positive correlation between the interaural difference of audiometric threshold and that of emission threshold in sudden deafness ears with various degrees of hearing loss. The incidence of continuous emission, whose duration was longer than 6 msec, was 30% in normal hearing ears and it was close to 90% in ears with bilateral or unilateral dip type hearing loss. The result was verified in a survey of a junior high school brass band. The conclusion is that there is clinical usefulness for the evoked otoacoustic emissions in evaluating cochlear function and in predicting noise susceptibility.     

小儿蜗后听觉神经损害的听力学特征

目的 探讨包含了听神经病在内的以听性脑干反应(ABR)严重异常、畸变产物耳声发射(DPOAE)正常为特征的蜗后听觉神经功能障碍小儿的听力学特征.方法 选取2002～2008年在广州市妇女儿童医疗中心听力专科检查中ABR严重异常(波Ⅴ阈值≥80 dB nHL)、DPOAE正常、排除中耳传导功能异常的患儿182例(350耳)为研究对象,患儿年龄4天～13岁,平均年龄15.67个月.结果 ①182例蜗后听觉神经损害患儿中,107例(58.79%)新生儿期有高胆红素血症,其中34例(18.68%)伴发核黄疸.在首次就诊的原因中,以"运动障碍"为主诉者最多,占32.42%(59例).因新生儿期听力损害高危因素进行听力评估而发现者占26.37%(48例).在伴随的疾病中,64例(35.16%)确诊伴随有脑性瘫痪.②本组182例蜗后病变患儿中,168例(占92.31%)双耳患病,14例(占7.69%)单耳患病.168例双耳均为蜗后病变的患儿中,最大强度刺激双耳均无Ⅰ波分化病例所占比例最高(94例,占55.95%).③在患蜗后听觉神经功能障碍的350耳中,172耳最大强度声刺激(103 dB nHL)ABR无波分化,69耳仅见波I分化,40耳见波I+Ⅲ+V分化,25耳仅见波V分化,20耳见波I+Ⅲ分化,15耳见波Ⅲ+V分化,5耳见波I+V分化,4耳见波Ⅲ分化.结论 高胆红素血症是包含听神经病在内的小儿蜗后听觉神经损害的最主要致病因素.小儿蜗后病变以双耳对称发病多见,双耳不对称患病的现象亦可出现,但相对少见.在蜗后听觉神经功能损害类型中,最常见的类型为ABR从波 I 开始就严重异常.小儿蜗后病变的听力学特征呈多样化.