Surgical management of conductive hearing loss in children

Patients with congenital conductive hearing loss present a surgical challenge. Surgeons must be aware of the potential altered anatomy, in particular the potential risks to the facial nerve and inner ear structures; however, meticulous attention to detail in the preoperative evaluation and in the operating room can minimize these risks. If surgery poses too high a risk to these structures, the chances of success are low, or there is a contraindication to surgery, traditional air-conduction hearing aids or bone-anchored hearing aids should be considered.     

Sensorineural hearing loss in the unoperated-on otosclerotic ear

Severe sensorineural hearing loss occurs in less than 1% of stapedectomized ears.^1?2 This low percentage remains as an irreducible minimum even among the most experienced and competent surgeons. The etiology has been hypothesized; however, the actual cause remains unknown. The rare occurrence of sensorineural hearing loss of undetermined etiology in the un-operated-on side was reported first in 1967 by Armstrong³ who presented a series of three patients. No other references have been found since this initial report. Recently three unilateral stapedectomized patients who developed sudden severe sensorineural hearing loss in the unoperated-on ear were studied during the years 1971 through 1979. The hearing loss occurred within 1 week, 6 weeks, and 12 years postoperatively. Although the number is small, a study of this group, in addition to Armstrong's, leads to several interesting considerations:

• 1 Is the incidence of sudden sensorineural type hearing loss greater, the same as, or less than that which develops in the non-otosclerotic general population?
• 1 Is there a possibility that the sudden sensorineural hearing loss of undetermined origin would occur at the time of surgery? Would this then be considered as a predisposing if not the actual etiology?

The present series of six cases is so small that a conclusion is not possible and inference is only conjecture. It is hoped, however, that this may stimulate past, present, and future search for this unusual occurrence. This may help determine whether or not there is a causal or merely a coincidental relationship.     

Cochleostomy site: Implications for electrode placement and hearing preservation

Conclusions. With recent increased interest in minimizing intracochlear trauma and preserving residual hearing during cochlear implantation, increased attention must be paid to the cochleostomy site. The results of this paper demonstrate that the cochleostomy must be made inferior, rather than anterior, to the round window to ensure scala tympani insertion and to decrease the likelihood of insertion-induced intracochlear damage during electrode insertion. Objective. To describe the complex anatomy of the hook region of the cochlea, specifically in relation to the optimal placement of the cochleostomy for cochlear implant electrode insertion to potentially achieve hearing preservation. The authors believe that previous industry recommendations and described surgical techniques have resulted in cochleostomies being placed in anatomical positions that possibly result in electrode insertions that damage the basilar membrane and/or other cochlear structures. Material and methods. The results of a number of temporal bone studies were reviewed with attention being paid to the anatomical relationship of the basilar membrane and spiral ligament to the round window membrane. For different cochleostomy sites the potential for damage to intracochlear structures, particularly the basilar membrane and organ of Corti, was assessed. Results. The review of electrode insertion studies into human temporal bones, as well as a post-mortem anatomical study of implanted temporal bones, showed an increased risk of scala vestibuli insertions and insertion-induced damage to intracochlear structures when the cochleostomy was performed more anterior to the round window. These results were endorsed by studies detailing the anatomy of the hook region of the cochlea.     

Outcomes for conservative management of traumatic conductive hearing loss.

OBJECTIVES: To evaluate the natural history of traumatic conductive hearing loss. STUDY DESIGN: Retrospective chart review. METHODS: Otologic and audiometric evaluations of patients in the early posttraumatic phase were compared with evaluations at follow-up. Assessment included etiologies of trauma, classification of hearing loss, factors causing conductive loss, and analyses of changes in air-bone gaps, pure-tone averages and hearing loss class. RESULTS: There were 45 patients, representing 47 ears, with sufficient initial and follow-up documentation to analyze the natural history of traumatic conductive hearing loss. Overall, 77% of ears showed an improvement in pure-tone averages without surgical intervention. Air-bone gaps closed from an average of 24.8 +/- 12.1 to 13.2 +/- 11.1 dB. Only 11% of ears demonstrated a decrease in pure-tone averages, and 12% showed no change in thresholds. All forms of injury contributing to the conductive hearing loss had good outcomes. Specifically, tympanic membrane perforations showed final air-bone gaps of 14.9 +/- 11.2 dB; cases of hemotympanum had final air-bone gaps of 10.0 +/- 8.1 dB; and suspected ossicular chain disruptions had final air-bone gaps of 13.9 +/- 12.3 dB. Only 5 of 47 ears ultimately required surgical intervention for persistent pathology. CONCLUSION: Patients with all forms of traumatic conductive hearing loss can be initially managed conservatively. Even suspected ossicular chain disruptions have a high rate of spontaneous reparation. Surgical intervention for perforation or conductive hearing loss should be undertaken in the rare cases when these conditions persist greater than 6 months.     

传导性耳聋外科治疗与相关研究进展

传导性耳聋的外科治疗作为耳科学的传统领域近十年来有了长足的进步。耳结构的重建与传声功能恢复成为临床治疗的主流;数字影像、新型材料、神经监测,导航技术与内镜的应用提高了临床诊断与治疗水平;相关基础研究活跃开展;以颞骨解剖和手术训练为主的继续教育促进了显微外科技术的普及与提高。本文就上述诸方面近十年的现状与未来发展做一简要评述。     

200例主观性耳鸣患者听力损失临床分析

目的:对耳鸣患者的听力损失进行分析,为进一步探讨耳鸣的发病原因、检查方法提供临床依据。方法:对以主观性耳鸣为主诉的200例患者进行耳科专科检查、声导抗检测、常频纯音听阈测听和高频扩展听阈测听检查。结果:200例耳鸣患者中,单侧耳鸣123例(61.5%),双侧耳鸣77例(38.5%);46例(23.0%)听力正常。单侧耳鸣中,患侧与对侧听阈比较0.125～8kHz差异有统计学意义(P<0.05),10kHz及其以上频率差异无统计学意义(P>0.05)。常频听力正常组与听力异常组比较各频率阈值差异均具有统计学意义(均P<0.05),听力异常组扩展高频检出率低于听力正常组。结论:耳鸣可以存在听力正常的人群中,扩展高频测听能否为耳鸣患者提供早期听力损失的依据,尚需对更多的临床资料进一步研究。     

Effect of conductive hearing loss on the vestibulo-collic reflex

The vestibulo-collic reflex represents a promising test for evaluating the integrity of otolith function. We have investigated the threshold of this response in a group of normal subjects, and the effect of a conductive hearing loss. A positive response was recorded in 31 of 32 normal subjects. The threshold of the vestibulo-collic reflex varied from 80 to 97 dBHL in these subjects with a 95% response rate at a threshold at96 dBHL. A total of 23 ears with a conductive hearing loss in 17 patients were also investigated. The average conductive hearing loss (at 0.5, 1, 2 and 4 kHz) ranged from 8.75 to 40 dBHL (average24.46 dBHL). A positive response was recorded in only two ears. Therefore, the vestibulo-collic reflex has a high stimulus threshold which is dependant on reliable transmission of the click stimulus to the inner ear thus limiting is clinical use.     

Possible role of peptides derived from otosclerotic bone in the mechanism of sensorineural hearing loss

Otosclerotic stapes footplates, superstructures and temporal cortical bones were extracted with 0.25 M guanidine X HCl 0.5 M EDTA (pH 7.4) solution. The extracted non-collagenous peptides/proteins were separated chromatographically on a Sephadex G-25 microcolumn. The peptide composition of the bone samples were compared by capillary analytical isotachophoresis (ITP) in the molecular mass range 0.3-5 kD. The otosclerotic stapes footplate contained 13 ITP subfractions, while the stapes superstructures and cortical bone contained only 9 and 10, respectively. An otosclerosis-specific ITP subfraction was also detected in the stapes footplate, but not in the stapes superstructure or cortical bone. This subfraction was previously demonstrated in the otosclerotic perilymph as well. Four ITP subfractions occurred common in the otosclerotic stapes footplate, the superstructure and the cortical bone. Two of these common subfractions were not found in the cortical bone peptide extract, but all of them revealed higher than normal levels in the otosclerotic perilymph.     

耳后注射甲强龙作为补救方案在中高频听力下降型突发性聋治疗中的疗效及可行性分析

目的探析中高频听力下降型突发性聋采取耳后注射甲强龙治疗的临床效果及可行性。方法选取2019年5月~2020年7月本院耳鼻喉科就诊的中高频听力下降型突发性聋患者,共纳入病例54例,以随机法分组,即常规组(n=27)和观察组(n=27),常规组予常规治疗,观察组采取耳后注射甲强龙,比较两组效果。结果观察组有效率相比于常规组显著提高(P<0.05);治疗3周后,观察组2000~8000Hz频率听力提高值与常规组比(P<0.05)。结论中高频听力下降型突发性聋采取耳后注射甲强龙治疗效果理想,值得推广。     

Effect of conductive hearing loss on the vestibulo-collic reflex.

The vestibulo-collic reflex represents a promising test for evaluating the integrity of otolith function. We have investigated the threshold of this response in a group of normal subjects, and the effect of a conductive hearing loss. A positive response was recorded in 31 of 32 normal subjects. The threshold of the vestibulo-collic reflex varied from 80 to 97 dBHL in these subjects with a 95% response rate at a threshold at 96 dBHL. A total of 23 ears with a conductive hearing loss in 17 patients were also investigated. The average conductive hearing loss (at 0.5, 1, 2 and 4 kHz) ranged from 8.75 to 40 dBHL (average 24.46 dBHL). A positive response was recorded in only two ears. Therefore, the vestibulo-collic reflex has a high stimulus threshold which is dependant on reliable transmission of the click stimulus to the inner ear thus limiting is clinical use.     

Loudness discomfort levels in patients with conductive and mixed hearing loss

OBJECTIVE: The purpose of this study is to investigate the effects of conductive component on the loudness discomfort level (LDL) judgments. The relation between LDL value and the magnitude of air-bone gap in such subjects was also assessed. METHODS: LDLs were obtained from 100 ears of 50 hearing-impaired subjects. Twenty five subjects (50 ears) had either conductive or mixed hearing loss for both ears. Another 25 subjects (50 ears) with bilateral sensorineural hearing loss served as control. LDL measurements were performed using the method reported by Hawkins et al. in 1987. LDL data were plotted and analyzed as a function of hearing loss for three stimulus frequencies (0.5, 1.0 and 2 kHz). Also, LDL values were plotted as a function of air-bone gap in the conductive group. RESULTS: LDLs were significantly higher in subjects with conductive or mixed hearing loss for all three tested frequencies. There is a significant positive correlation between LDL value and the magnitude of air-bone gap for all three test frequencies. Considerable intersubject variability was found in LDLs obtained from subjects with conductive component which prevented the accurate prediction of LDLs from threshold data for such patients. CONCLUSION: The large intersubject variation in LDL data strongly suggests the need for individualized LDL measurements in patients with conductive or mixed hearing loss. Higher LDLs indicates that higher maximal power output can be prescribed for such patients without worrying about loudness intolerance.     

Wideband aural acoustic absorbance predicts conductive hearing loss in children

Abstract

Objective: This study tested the hypothesis that wideband aural absorbance predicts conductive hearing loss (CHL) in children medically classified as having otitis media with effusion. Design: Absorbance was measured in the ear canal over frequencies from 0.25 to 8 kHz at ambient pressure or as a swept tympanogram. CHL was defined using criterion air-bone gaps of 20, 25, and 30 dB at octaves from 0.25 to 4 kHz. A likelihood-ratio predictor of CHL was constructed across frequency for ambient absorbance, and across frequency and pressure for absorbance tympanometry. Performance was evaluated at individual frequencies and for any frequency at which a CHL was present. Study sample: Absorbance and conventional 0.226-kHz tympanograms were measured in children of age three to eight years with CHL and with normal hearing. Results: Absorbance was smaller at frequencies above 0.7 kHz in the CHL group than the control group. Based on the area under the receiver operating characteristic curve, wideband absorbance in ambient and tympanometric tests were significantly better predictors of CHL than tympanometric width, the best 0.226-kHz predictor. Accuracies of ambient and tympanometric wideband absorbance did not differ. Conclusions: Absorbance accurately predicted CHL in children and was more accurate than conventional 0.226-kHz tympanometry.     

Bone conductive implantation in asymmetric hearing loss (AHL)

Abstract

Background: Bone conductive implants (BCI) represent one possible solution for rehabilitation of single-sided deafness (SSD).

Aims: The aim of the present study was to verify the efficacy of bone conduction implantation in subjects with unilateral severe-to-profound hearing loss and contralaterally impaired hearing, that is, asymmetric hearing loss (AHL), and to compare it with known BCI indications for SSD.

Material and methods: Twenty-one subjects received BCI for either SSD or AHL. All of the subjects underwent a battery of audiological and subjective tests, Data were collected and statistically evaluated within and between the SSD group and the AHL group.

Results: A PTA threshold gain was observed in AHL patients along with improved values in speech audiometry in quiet and noise. The two visual analogue scale evaluations (QoL and QoS) and the GBI showed significantly better scores in AHL patients compared to SSD patients.

Conclusions: BCI provided improvement for auditory or speech recognition in AHL subjects, as compare to SSD. From these findings, it is possible to predict a positive role of BCI for some audiological aspects of AHL subjects that are generally not present or not detectable in SSD cases.     

Mixed conductive and sensorineural hearing loss in LP/J mice

Air and bone conduction thresholds for the detection of a compound action potential response were measured in mice of the LP/J inbred strain, which has been proposed as a possible model for human otosclerosis. Thresholds were compared with control data from CBA/Ca mice. Evidence of a mixed sensorineural and conductive hearing loss was obtained in LP/J mice. Few signs of hair cell degeneration or middle-ear bony lesions were found in 20-day old mice, although they generally showed raised thresholds to both air and bone conducted stimuli. The reason for the observed sensorineural component of the hearing loss at this age is not clear, since endocochlear potentials were normal in mice of this strain. By 225 days of age, hair cell loss was extensive and there was clearly excess bone growth in all middle-ear specimens studied, particularly on the incus and the cochlear wall facing the middle ear. Microbiological analysis of LP/J specimens revealed no evidence of a middle-ear infection specific to these mice which might explain the pathology.     

TAP deficiency syndrome: chronic rhinosinusitis and conductive hearing loss

Nose-ear-throat manifestations of immunodeficiency disorders represent a diagnostic challenge for clinicians as these diseases often constitute the initial sign for connective disorders or autoimmune disease. The history of chronic rhinosinusitis and conductive hearing loss is often non specific. Therefore attention to an HLA class I deficiency must be considered if the disease has not been diagnosed on routine examination. One of the syndromes is due to a defective TAP complex, the peptide transporter complex associated with antigen presentation. Herein, we report two sisters with TAP-deficiency. The treatment of choice for TAP-deficient patients is conservative.