1,000 ear operations--a critical analysis and clinical consequences]

1028 ear operations which were performed by our department during the last few years are being analysed in the study. 649 of them were carried out to improve hearing, 245 to cure the middle ear; 120 were reoperations, and 14 could not be classified. The patients were diagnosed as follows: 280 with and 279 with other forms of cholesteatoma, 151 with otosclerosis, 20 with deformations, 89 with a trauma, and 20 with a tumour of the middle ear. Of these, only reoperations of cholesteatoma, chronic otitis media and tympanosclerosis were examined in further detail in this research. 54 (of a total of 280) patients diagnosed with cholesteatoma were surgically treated a second time. The reason for reoperation was recurrent cholesteatoma in 70% of the cases, and a planned second-look operation after one year in 30%. In second-look operations, ossicular chain reconstruction was performed in most cases, but in another 11%, recurrent cholesteatoma was found. The majority of recurrencies occurred either 2 to 4 years after primary operation or after 11 years. 44 of a total of 297 patients with chronic mesotympanic otitis media were re-operated on: 57% of them for recurrent inflammation, and 43% for ossicular chain reconstruction as a planned second-step operation. The majority of reoperations occurred within the first year after primary operation, continually decreasing for up to five years afterwards. The following conclusions can be drawn from these results: 1. Often the patients suffer from extended cholesteatoma, so that at first curative surgery is necessary, while the ossicular chain can be reconstructed by a second operation only.(ABSTRACT TRUNCATED AT 250 WORDS)     

Differential protective effects of neurotrophins in the attenuation of noise-induced hair cell loss

The protective efficacy of neurotrophin-3 (NT-3) and brain-derived neurotrophic factor (BDNF) at 1 or 10 microg/ml was assessed in guinea pigs exposed to 4 kHz octave band noise at 115 dB SPL for 5 h. BDNF, NT-3 or artificial perilymph was delivered to the scala tympani via a mini-osmotic pump, beginning 4 days prior to noise exposure and continuing for 1 week post-exposure. Protection was assessed physiologically by the change in auditory brainstem response (ABR) threshold, and histologically by outer hair cell (OHC) survival. There was a statistically significant increase in OHC survival and a decrease in ABR threshold shift in animals receiving NT-3 at a concentration of 10 microg/ml. In animals receiving 1 microg/ml NT-3, there was a significant increase in OHC survival in the first row of OHC, but no significant change in ABR threshold, relative to control animals. In animals treated with BDNF, no significant functional or histological protection was observed. The protection afforded by NT-3 (10 microg/ml) treatment was similar in magnitude to that reported previously with glial cell line-derived neurotrophic factor and suggests that several factors may be involved in the protective response.     

不同类型鼓室图患者中耳共振频率分析

目的 探讨不同类型鼓室图患者的听力损失情况及其对应的中耳共振频率变化。方法 使用听力计对患者进行纯音测听检查,了解其听力损失的性质、程度;使用中耳分析仪进行常规中耳功能分析,根据不同类型的静态鼓室图形进行分组;分别对听力正常组(30耳)、异常组(116耳)［鼓室图为A型(30耳)、Ad型(22耳)、As型(21耳)和C型(43耳)］行中耳共振频率检查。结果 正常组的中耳共振频率为(951.00±198.85)Hz;听力异常组中A型鼓室图的中耳共振频率为(861.00±137.60) Hz (P<0.01), Ad型为(725.00±158.14) Hz (P<0.01), C型为(499.00±146.27) Hz(P<0.01),三组中耳共振频率分别比正常组低;As型为(1088.00±199.38) Hz(P<0.05)比正常组高。结论 中耳共振频率的检测有助于中耳疾病的诊断及治疗。     

Real ear attenuation at threshold for three audiometric headphone devices: implications for maximum permissible ambient noise level standards.

Attenuation measurements were made using the ANSI S12.6-1984 protocol on a standard Telephonics headset with TDH-50P earphones and Model 51 cushions, Amplivox Audiocups headphone enclosures, and Peltor AudioMate headphone enclosures. Each of the enclosures housed Telephonics TDH-50P earphones with Model 51 cushions. The mean attenuation values obtained were compared with those previously reported, and reasons for discrepancies were analyzed. Pure-tone threshold shifts in background noise complying with ANSI S3.1-1977 and Occupational Safety and Health Administration (1983) maximum permissible ambient noise level standards were estimated on the basis of the attenuation values for each headphone device, and the adequacy of these current standards for accurate pure-tone threshold assessment was considered. The results indicated that Model 51 cushions alone are insufficient to attenuate the ambient noise levels permitted under ANSI S3.1-1977, and even the utilization of noise-excluding headphone enclosures does not reduce the background noise levels permitted under the Occupational Safety and Health Administration (1983) to a sufficient degree to permit testing down to 0 dB HL.     

Real-ear output measures of ear level fluency devices

Abstract

Objective: The purpose of this study was to measure real-ear aided and saturated responses of SpeechEasy^? devices and compare responses while devices delivered altered auditory feedback (AAF) and non-altered feedback (NAF). Design: A repeated measures quasi-experimental design was employed. Study sample: Ten people fitted with completely-in-the-canal or open fit behind-the-ear devices participated. Probe microphone measures were obtained with speech, and 17 chirp stimuli presented at 75 dB and 85 dB SPL, respectively. Measurements were compared with devices delivering AAF (i.e. delayed and frequency shifted) versus NAF. Results: Maximum outputs were approximately 100–105 dB SPL in the 2000–4000 Hz range. Statistically significant differences in device SPL output as a function of device setting (AAF vs. NAF) were found for seven chirp stimuli (p <.05) when levels were sampled at points that were not temporally aligned with the output chirps but not for speech stimulus (p = .17). Device output varied across individuals and with open fit devices dominated by ear canal resonance effects. Conclusions: Real-ear aided responses were equivalent with speech input when devices delivered AAF and NAF. Real-ear saturated responses were not, however, comparable between AAF and NAF settings and may be underestimated if AAF delay is not accounted for.     

Otorrhoea in children with middle ear ventilation tubes: a comparison of different types of tubes

Otorrhoea is a troublesome complication of middle ear ventilation tubes. This investigation of children with various ventilation tubes shows that the incidence of this complication varies with the type of tube used. In particular, Paparella type 2 tubes are associated with a higher rate of otorrhoea, and should be reserved for use when long-term ventilation is necessary.     

睫状神经营养因子防治强脉冲噪声对豚鼠内耳损伤的实验研究

目的探索应用睫状神经营养因子（ｃｉｌｉａｒｙｎｅｕｒｏｔｒｏｐｈｉｃｆａｃｔｏｒ,ＣＮＴＦ）防治强脉冲噪声对豚鼠内耳损伤的可能性,为强脉冲噪声致聋的防治提供新的方法。方法制作强脉冲噪声致聋豚鼠模型３６只,１８只应用ＣＮＴＦ肌内注射３周,１８只等量的生理盐水作对照,正常对照豚鼠１８只,进行耳蜗铺片计算机图像分析毛细胞计数,螺旋神经节细胞计数、耳蜗乙酰胆碱酯酶染色铺片观察和ＡＢＲ反应阈测定。结果正常对照组、噪声暴露后２１ｄ的生理盐水对照组和ＣＮＴＦ组耳蜗毛细胞平均总数（ｘ±ｓ,下同）分别为９０９４±１０３．６、７３５１±１９６．５、８５２２±２０３．１;而螺旋神经节细胞计数在耳蜗中轴切片第二回下段３组间差异有显著性,分别为５１±４．７２、２７±６．９４、３７±１０．４。乙酰胆碱酯酶染色铺片结果示ＣＮＴＦ组较生理盐水对照组耳蜗乙酰胆碱酯酶活性损失轻、范围小。结论ＣＮＴＦ在一定程度上能防止受损的螺旋神经节细胞及外毛细胞发生变性坏死,并可能促进其损伤的修复。     

Otorrhoea in children with middle ear. ventilation tubes: a comparison of different types of tubes

Otorrhoea is a troublesome complication of middle ear ventilation tubes. This investigation of children with various ventilation tubes shows that the incidence of this complication varies with the type of tube used. In particular, Paparella type 2 tubes are associated with a higher rate of otorrhoea, and should be reserved for use when long-term ventilation is necessary.     

The protective effects of ciliary neurotrophic factor on inner ear damage induced by intensive impulse noise]

OBJECTIVE: To evaluate the feasibility of using ciliary neurotrophic factor(CNTF) to treat intensive impulse noise-induced inner ear damage. METHODS: The guinea pigs were given either CNTF (CNTF group) or 0.9% sodium chloride (NS group) for 3 weeks after impulse noise exposure. The animals receiving neither medicine nor noise served as a control group. ABR threshold shifts, the cochlear AchE staining as well as the hair cell and spiral ganglion cell counting were carried out in three groups of animals. RESULTS: The numbers of damaged hair cells and spiral ganglion cells in the CNTF group was less than that in the NS group. AchE activity alteration was also less severe in the CNTF group. Similar to the morphological results, changes in the auditory function, represented by the ABR threshold shifts, was less in the CNTF group. CONCLUSION: CNTF can protect cochlear hair cells and spiral ganglion cells against intensive impulse noise exposure by decreasing degeneration and necrosis of the hair cells in some extent and expedite hearing recovery.     

不同类型听力下降伴耳鸣治疗的疗效分析

目的通过分析耳鸣与听力下降的关系,总结耳鸣与不同类型听力下降的关联性,以及不同类型听力下降所伴有耳鸣的治疗效果。方法分析2016年1月~2017年6月因“耳鸣”或者因“听力下降伴有耳鸣”就诊的急性耳鸣患者188例,其中男102例,女86例;年龄23~62岁,平均年龄44岁。双侧耳鸣者65例,单侧耳鸣者123例。所有患者入院时均进行电测听及耳鸣检查,根据听力曲线类型对耳鸣患者进行分组,其中听力正常者12例,低频听力下降者36例,高频听力下降者84例,平坦听力下降者42例,全聋型14例。入院后所有患者予以行营养神经、改善循环、激素冲击等治疗,并于入院当日、第3天、第5天及第10天行听力检查及耳鸣检查,比较各组患者耳鸣治疗的疗效。结果不同听力下降类型的耳鸣患者构成比比较,差异具有统计学意义（P＜0.05）。听力正常者耳鸣治疗有效率为91.67%（11/12）,低频听力下降组耳鸣治疗有效率为83.33%（30/36）,高频听力下降组耳鸣治疗有效率为54.76%（46/84）,平坦型听力下降组耳鸣治疗有效率为69.05%（29/42）,全聋型听力下降组耳鸣治疗有效率为28.57%（4/14）,对各组的耳鸣治疗有效率进行比较,差异具有统计学意义（P＜0.05）。结论高频听力下降者耳鸣发生率最高,听力正常者耳鸣发生率最低。听力正常及低频听力下降者耳鸣治疗有效率最高,高频听力及全聋者耳鸣治疗效果较差。     

Local treatment of the inner ear: A study of three different polymers aimed for middle ear administration

Conclusion: A formulation based on sodium hyaluronate (NaHYA) was the most promising candidate vehicle for intra-tympanic drug administration regarding conductive hearing loss, inflammatory reactions, and elimination. Objectives: Recent advances in inner ear research support the idea of using the middle ear cavity for drug administration to target the inner ear. This paper presents rheological and safety assessments of three candidate polymer formulations for intra-tympanic drug administration. Method: The formulations were based on sodium carboxymethyl cellulose (NaCMC), sodium hyaluronate (NaHYA), and poloxamer 407 (POL). Rheological studies were performed with a controlled rate instrument of the couette type. Safety studies were performed in guinea pigs subjected to an intra-tympanic injection of the formulations. Hearing function was explored with ABR before and 1, 2, and 3 weeks after the injection. Elimination of the formulations marked with coal was explored with an endoscopic digital camera 1, 2, and 3 weeks after injection. Middle and inner ear morphology was examined with light microscopy 6 days after injection. Results: The results speak in favor of NaHYA, since it did not cause prolonged hearing threshold elevations. The results of the elimination and morphological investigations support the conclusion of NaHYA being the most promising candidate for intra-tympanic administration.     

Finite element analysis of multi-piece post-crown restoration using different types of adhesives

The multi-piece post-crown technique is more effective in restoring residual root than other restoration techniques.Various types of adhesives have different material properties that affect restoration.Therefore,the choice of adhesive is particularly important for patients.However,the effect of different kinds of adhesives was not too precise by experimental methods when concerning about individual differences of teeth.One tooth root can only be restored with one type of adhesive in experiment.After the mechanical test,this tooth root cannot be restored with other adhesives.With the help of medical imaging technology,reverse engineering and finite element analysis,a molar model can be reconstructed precisely and restored using different types of adhesives.The same occlusal and chewing loads were exerted on the same restored residual root models with different types of adhesives separately.Results of von Mises stress analysis showed that the adhesives with low Young’s modulus can protect the root canal effectively.However,a root canal concentration is apparently produced around the root canal orifice when chewing.Adhesives with large Young’s modulus can buffer the stress concentration of the root canal orifice.However,the root canal tissue may be destroyed because the adhesive is too hard to buffer the load.