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Background: Imaging plays an important role in the management of middle ear pathology. Temporal bone imaging is challenging and involves deep understanding of the anatomy, especially in relation to high resolution computed tomography (HRCT) imaging. An HRCT scan can precisely determine the site and extension of cholesteatoma and its sac, assessing the erosion of ossicles, evaluating the facial nerve in its entire course, tegmen and sinus plate, and determining Dural, sigmoid sinus, and jugular bulb positions. Methods: This prospective descriptive study was performed from January 2018 to May 2019 in 60 patients with cholesteatoma who were referred to the Otolaryngology department of the Command Hospital Kolkata. Preoperative high-resolution temporal bone CT scans were carried out and compared with intraoperative findings. Results: Evaluation of 60 patients and their CT scans revealed excellent correlation for presence of soft tissue mass and its extent into the middle ear and mastoid, erosion of scutum, erosion of ossicular chain and tegmen plate, good correlation for facial canal dehiscence, labyrinthine fistula and sinus plate erosions. Conclusions: HRCT temporal bone is essential for anatomical determination of cholesteatoma and its complication. Careful and thorough evaluation is needed for the early diagnosis and treatment of the disease, to prevent complications and preserve hearing. The extent of disease and associated complications like facial nerve paralysis, labyrinthine fistula, and intracranial complications often will determine the aggressiveness of the surgical approach.
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Background: Imaging plays an important role in the management of middle ear pathology. Temporal bone imaging is challenging and involves deep understanding of the anatomy, especially in relation to high resolution computed tomography (HRCT) imaging. An HRCT scan can precisely determine the site and extension of cholesteatoma and its sac, assessing the erosion of ossicles, evaluating the facial nerve in its entire course, tegmen and sinus plate, and determining Dural, sigmoid sinus, and jugular bulb positions. Methods: This prospective descriptive study was performed from January 2018 to May 2019 in 60 patients with cholesteatoma who were referred to the Otolaryngology department of the Command Hospital Kolkata. Preoperative high-resolution temporal bone CT scans were carried out and compared with intraoperative findings. Results: Evaluation of 60 patients and their CT scans revealed excellent correlation for presence of soft tissue mass and its extent into the middle ear and mastoid, erosion of scutum, erosion of ossicular chain and tegmen plate, good correlation for facial canal dehiscence, labyrinthine fistula and sinus plate erosions. Conclusions: HRCT temporal bone is essential for anatomical determination of cholesteatoma and its complication. Careful and thorough evaluation is needed for the early diagnosis and treatment of the disease, to prevent complications and preserve hearing. The extent of disease and associated complications like facial nerve paralysis, labyrinthine fistula, and intracranial complications often will determine the aggressiveness of the surgical approach.
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Introduction: The tympanic cavity contains three ossicles in humans, the malleus, incus and stapes. These ossicles form a chain across the tympanic cavity from the tympanic membrane to fenestra vestibuli respectively. They develop from mesenchymal condensation of tubotympanic recess at the 6th week of intrauterine life. Later due to programmed cell death a part of tissue remains as ossicles. It attains adult size in the fetal life itself. However, studies have shown gain in size and weight even 2 years after birth. The ossicles help in sound conducting mechanism in hearing. These ossicles are vulnerable to damage in the various diseases of the middle ear cleft resulting into either partial or total loss. Incus is the most, followed by stapes and least by malleus. 20% mucosal diseases show ossicular damage, while squamous epithelial disease involve in 80% [1,2]. The integrity of the ossicular chain is most important for the transmission mechanism of external sounds to the inner ear fluids. Objectives: 1. To study the percentage of ossicular damage in the diseases of the middle ear cleft among the patients being operated for chronic suppurative otitis media in our tertiary care hospital. 2.To assess the extent and frequency of individual ossicular chain involvement in simple mucosal disease and squamous epithelial diseases. Methods: A prospective clinical study was conducted in our tertiary care hospital over a period of five and a half years in our tertiary care hospital among 100 cases of chronic suppurative otitis media after ethical committee clearance. Detailed clinical and radiological examinations of the patients were done and ossicular chain status was noted on table. Patients were also called up for regular follow up. Results: Ossicular chain erosion was mostly seen in squamosal disease, with incus and incudo-stapedial joint being the most common sites for ossicular erosion. Conclusion: it was concluded that long process of incus was the most commonly eroded structure, with the incus being the most commonly involved ossicle Few factors that were found to be associated with ossicular erosion were atticoantral disease, pediatric age group and bigger tympanic membrane perforations.
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@#A 27-year-old man undergoes otolaryngologic evaluation for blunt head trauma suffered in a vehicular accident. With regards to the right ear, pertinent otologic findings include an ear canal laceration and a delayed-onset facial nerve paresis. Tuning fork testing reveals an abnormal Rinne test on the right (AC<BC). The radiologist’s interpretation of the computerized tomographic imaging study of the temporal bone indicated the presence of a longitudinal fracture of the right temporal bone with no disruption of the ossicular chain. (Figure 1) However, careful examination of the anatomy of the malleo-incudal complex in relation to the other structures in the epitympanum actually reveals findings indicative of a malleo-incudal complex dislocation. How can this discrepancy in the radiologic interpretation be accounted for? By what objective parameters can the presence of a malleoincudal complex dislocation be identified?
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Osso Temporal , Diagnóstico por Imagem , Ossículos da OrelhaRESUMO
Abstract Introduction The goal of ossiculoplasty is to improve hearing and the success of this procedure depends on several factors. Objective Analyze the hearing results in patients with chronic otitis media undergoing ossicular chain reconstruction, as well as predictive factors for successful surgery. Methods Charts of patients undergoing ossiculoplasty between 2006 and 2016 were reviewed. Sixty-eight patients were included, totaling 72 ears. The following data was analyzed: gender, age, smoking status, laterality, pathology, audiometric exams, type of surgery, previous surgery, characteristics of the middle ear, otorrhea and ossicular chain status. Patients were also classified according to two indices: middle ear risk index and ossiculoplasty outcome parameter staging. The results were evaluated by comparing the air-bone gap before and after surgery. The success of reconstruction was defined as air-bone gap ≤20 dB and the improvement of speech reception Thresholds, calculated through the mean frequencies 0.5, 1, 2 and 3 kHz. Results Reconstruction success rate was 61%. The mean preoperative air bone gap was 34.63 dB and decreased to 17.26 dB after surgery. There was a correlation between low risk in middle ear risk index and ossiculoplasty outcome parameter staging indices with postoperative success. The most frequently eroded ossicle was the incus and the type of prosthesis most used was tragal cartilage. In the patients without incus, we achieved success in 74.2% of the surgeries. In the absence of the stapes, the success rate decreased to 63.3%. In the absence of the malleus, 85% of the patients had and air bone gap ≤20 dB. Conclusion We achieved good audiometric outcomes in ossiculoplasty and the results are comparable to other centers. Ossicle status influenced postoperative results, especially in the presence of stapes. We also concluded that the indexes analyzed may help to predict the success of the surgery.
Resumo Introdução A ossiculoplastia tem como objetivo a melhoria da audição e o sucesso desse procedimento depende de diversos fatores. Objetivo Analisar os resultados auditivos em pacientes com otite média crônica submetidos a reconstrução da cadeia ossicular, bem como os fatores preditivos de sucesso cirúrgico. Método Prontuários de pacientes submetidos a ossiculoplastia entre 2006 e 2016 foram revistos. Sessenta e oito pacientes foram incluídos, total de 72 orelhas. Os seguintes dados foram analisados: sexo, idade, tabagismo, lateralidade, doença, exames audiométricos, tipo de cirurgia, cirurgia prévia, características da orelha média, otorreia e estado da cadeia ossicular. Os pacientes também foram classificados de acordo com dois índices: índice de risco da orelha média e estadiamento do parâmetro de desfecho da ossiculoplastia. Os resultados foram avaliados comparando o gap aéreo-ósseo antes e após a cirurgia. O sucesso da reconstrução foi definido como gap aéreo-ósseo ≤ 20 dB e a melhoria dos limiares de recepção de fala, calculados pelas frequências médias de 0,5, 1, 2 e 3 kHz. Resultados A taxa de sucesso da reconstrução foi de 61%. O gap aéreo-ósseo pré-operatório médio foi de 34,63 dB e diminuiu para 17,26 dB após a cirurgia. Houve correlação entre baixo risco no índice de risco para orelha média e os índices de estadiamento do parâmetro de desfecho da ossiculoplastia com sucesso pós-operatório. O ossículo com erosão mais frequente foi a bigorna e o tipo de prótese mais utilizada foi a cartilagem tragal. Nos pacientes sem bigorna o sucesso foi alcançado em 74,2% das cirurgias. Na ausência do estribo, a taxa de sucesso diminuiu para 63,3%. Na ausência do martelo, 85% dos pacientes apresentaram gap aéreo-ósseo ≤ 20 dB. Conclusão Melhora significativa da audição foi observada em pacientes submetidos à ossiculoplastia, os resultados foram comparáveis aos de outros centros. O "status" dos ossículos influenciou os resultados pós-operatórios, principalmente a presença do estribo. Também concluímos que os índices analisados podem ajudar a prever o sucesso da cirurgia.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Otite Média/cirurgia , Prótese Ossicular/normas , Ossículos da Orelha/cirurgia , Audição/fisiologia , Período Pós-Operatório , Prognóstico , Audiometria , Timpanoplastia , Índice de Gravidade de Doença , Doença Crônica , Resultado do Tratamento , Medição de Risco , Recuperação de Função FisiológicaRESUMO
Objective To study the influence of middle ear malformation on the performance of round window stimulation, so as to provide references for optimization of the round window stimulation middle ear implant. Methods The finite element model of human ear including an asymmetrical two-cavity non-helical cochlea was constructed and compared with experimental data to verify reliability of the model. Based on this model, the effects of three kinds of middle ear malformation, i.e., ossicular chain fixation, ossicular chain fusion and ossicular defect on round window stimulation were simulated by changing material properties of the corresponding tissues. Results The middle ear malformation mainly affected the low-frequency performance of round window stimulation. The ossicular chain fixation and the ossicular chain fusion had a deteriorating effect on round window stimulation. The stapes fixation had the greatest effect on the performance of round window stimulation, with the reduction as high as 47.93 dB. Ossicles defects could improve the performance of round window stimulation, with the maximum increment of 6.24 dB. Conclusions The middle ear malformation had an effect on the low frequency performance of round window stimulation. It is necessary to specifically increase output of the actuator when implanting the round window stimulation middle ear implant.
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Background: Tympanoplasty refers to any operation involving reconstruction of the tympanic membrane and/or the ossicular chain. Myringoplasty is a Tympanoplasty without ossicular reconstruction. Chronic otitis media is one of the commonest Otological problems among Sudanese, in both adult and children (43%) and they presented with perforation of the eardrum and different degrees of hearing loss. Aim: To evaluate the audiological and surgical results of tragal cartilage graft in myringoplasty for reconstruction of tympanic membrane perforation. Materials and methods: A total of 25 patients in the age group of 16 - 60 years suffering from chronic suppurative otitis media of tubotympanic type, attending the outpatient department at Rajah Muthiah Medical College and hospital and underwent tragal cartilage myringoplasty between October 2015 to August 2017 were included in the study. Results: The mean preoperative pure tone average was 37 and the postoperative pure tone average was 25.80 at 6th week and 15.60 at 10th week. The calculated p-value was less than 0.001 which was statistically significant. Graft uptake was 92% in our study. There was no postoperative retraction. Postoperative reperforation was seen in 2 (8%) patients. Conclusion: Graft takeup in tragal cartilage myringoplasty has been excellent, hearing results are satisfactory and complications are minimal. Immobility of the transplant during the early stages of the healing process is the most important factor for the successful surgical outcome of myringoplasty.
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Objective To explore the application value of 256-slice high resolution CT(HRCT)and reconstuction technique in the preoperative assessment of ossicular chain trauma.Methods 106 cases of temporal bone trauma were scanned using 256-slice HRCT,38 cases of ossicular chain trauma were collected.The multi-planar reformaition(MPR),curved plannar reformation(CPR) and three-dimensional volume rendering reformation (3D VR)of the ossicular chain were performed on Philips work station.The locations, types and the involving structures were analyzed,then these cases were followed up.The display rates of AX,MPR,CPR,3D VR were evaluated.Results Among 106 cases of temporal bone trauma,38 cases(76 ears)were found ossicular chain trauma,in which there were 43 ears of ossicular dislocation,22 ears incudomalleolar joint separation,6 ears incudomalleolar and incudostapedial joint separation,3 ears incudostapedial joint separation,11 ears translocation of the ossicles,1 ear stapediovestibular dislocation;4 ears ossicular fractures,2 ears fracture of the malleus,1 ear fracture of the incus,1 ear fracture of the stapes.Among 38 cases,11 cases underwent surgery,and the surgical results were consistent with CT findings.The display rates of AX,MPR,CPR,3D VR were 97.87%,100%, 97.87%,82.98% respectively.Conclusion 256-slice HRCT and reconstuction technique can clearly reveal the whole structure of ossicular chain trauma,which are effective methods for diagonsis of ossicular chain trauma before surgery.
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Objective To explore the application value of 256-slice high resolution CT(HRCT)and reconstuction technique in the preoperative assessment of ossicular chain trauma.Methods 106 cases of temporal bone trauma were scanned using 256-slice HRCT,38 cases of ossicular chain trauma were collected.The multi-planar reformaition(MPR),curved plannar reformation(CPR) and three-dimensional volume rendering reformation (3D VR)of the ossicular chain were performed on Philips work station.The locations, types and the involving structures were analyzed,then these cases were followed up.The display rates of AX,MPR,CPR,3D VR were evaluated.Results Among 106 cases of temporal bone trauma,38 cases(76 ears)were found ossicular chain trauma,in which there were 43 ears of ossicular dislocation,22 ears incudomalleolar joint separation,6 ears incudomalleolar and incudostapedial joint separation,3 ears incudostapedial joint separation,11 ears translocation of the ossicles,1 ear stapediovestibular dislocation;4 ears ossicular fractures,2 ears fracture of the malleus,1 ear fracture of the incus,1 ear fracture of the stapes.Among 38 cases,11 cases underwent surgery,and the surgical results were consistent with CT findings.The display rates of AX,MPR,CPR,3D VR were 97.87%,100%, 97.87%,82.98% respectively.Conclusion 256-slice HRCT and reconstuction technique can clearly reveal the whole structure of ossicular chain trauma,which are effective methods for diagonsis of ossicular chain trauma before surgery.
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OBJECTIVE To share surgical experience of ossicular chain malformations with CO2 laser.METHODS A retrospective analysis was performed.9 patients with clinical diagnosis of ossicular malformations underwent ossicular reconstruction with CO2 laser-assisted from May 2010 to Mar 2016,the results were evaluated by comparing preoperative and postoperative audiometric outcomes and the rate of postoperative complications.RESULTS 8 cases with complex lesion combining incus and stapes were found intraoperatively,the deformity located on stapes was showed in one case.The mean postoperative air conduction (AC) value was (26.53 ± 12.28) dB,the mean postoperative air-bone gap (ABG) was (9.44 ± 9.62) dB,the postoperative AC and ABG value improved considerably comparing with the preoperative value in all the patients,the difference was statistically significant.CONCLUTION CO2 laser is a suitable and effective adjunct in surgery for ossicular malformations such as otosclerosis.The use of the laser improves hearing results and operation efficiency and is not likely to increase side-effects to patients.
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Pigmentation is a well-recognized complication of minocycline use. This is the first reported case of ossicular chain pigmentation as a consequence of this drug. Isolated pigmentation of the lenticular process of the incus bone was noted. The structural integrity and function of the ossicular chain was not influenced by these changes.
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A tomografia computadorizada tem papel fundamental no estudo do aparelho auditivo, uma vez que, através dela pode-se avaliar estruturas não visualizadas no exame com otoscópio. Em situações clínicas diversas, o diagnóstico, por meio desse exame, mostra-se limitado, sendo fundamental oexame de imagem associado às reformatações multiplanar reconstruction, maximum intensity projection e volume rendering technique. A cadeia ossicular é uma estrutura formada pelos ossículosmartelo, bigorna e estribo, situados na orelha média, sendo difícil visualizá-los nos planos ortogonais. Este artigo de revisão bibliográfica pretende demonstrar a importância da reformatação de imagem da cadeia ossicular para uma melhor representação da anatomia e das possíveis enfermidades. A reformatação das imagens auxilia, significativamente, para uma melhor visualização dessasestruturas relacionadas como malformações congênitas, anomalias vasculares, condições inflamatórias, neoplásicas e traumas.
Computed tomography has a key role in the study of hearing, since through it can be evaluated structures not seen by otoscope. In many clinical situations the diagnosis through this test proves limited, being fundamental examination of the associated image reconstructions:multiplanar reconstruction, maximum intensity projection, and volume-rendering technique. The ossicular chain is a complex formed by the ossicles malleus, incus and stapes, situatedin the middle ear; it is difficult to view them in orthogonals planes. This review article intends to demonstrate the importance of post-processing the image of the ossicular chain for a betterrepresentation of the anatomy and possible diseases. Reformattingof images helps, significantly, to a better visualization of these structures as related congenital malformations, vascular abnormalities, inflammatory conditions, neoplasia and traumas.
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Ossículos da Orelha , Orelha Média , Desenvolvimento Tecnológico , Tomografia Computadorizada por Raios X/métodosRESUMO
A Otite Média Crônica é definida pela presença de alterações teciduais inflamatórias irreversíveis na fenda auditiva. As lesões ossiculares são as mais prevalentes. OBJETIVO: Correlacionar o grau de comprometimento da cadeia ossicular, visualizada no transoperatório, com o grau histológico de inflamação e com a espessura da perimatriz de colesteatomas. TIPO DE ESTUDO: Estudo transversal. MÉTODOS: Descrições cirúrgicas de 71 pacientes foram revisadas. Colesteatomas coletados e fixados em formol 10 por cento e preparadas uma lâmina em Hematoxilina-Eosina e outra em Picrossírios. A leitura foi "cega", através de imagens digitais, no ImageProPlus. A análise estatística foi realizada através do coeficiente de Spearman, sendo considerados como estatisticamente significativos os valores de P≤0,05. RESULTADOS: Havia algum envolvimento da cadeia ossicular em 65 casos. O ossículo mais freqüentemente afetado era a bigorna, seguida pelo estribo e pelo martelo. Ao aplicarmos o coeficiente de Spearman entre o grau de comprometimento da cadeia ossicular com a idade do paciente à cirurgia, a espessura da perimatriz e o grau histológico de inflamação não foram detectadas correlações. CONCLUSÃO: Os nossos achados indicam que é praticamente universal o acometimento da cadeia ossicular na presença de colesteatoma. Não foi encontrada correção entre a erosão ossicular e os achados histológicos.
Chronic otitis media is hystopathologycaly defined as the presence of irreversible inflammatory tissue changes in the middle ear. Ossicular lesions represent the most prevalent change. AIM: to correlate the degree of ossicular chain changes seen during surgery with the inflammatory histological degree and the thickness of the cholesteatoma perimatrix. STUDY DESGN: Cross-sectional study. METHODS: Seventy-one descriptions of surgeries done in patients submitted to tympanomastoydectomy were reviewed. Cholesteatoma were collected and fixed in 10 percent formaldehyde. Two slides were made for each cholesteatoma, one stained with HE and another with picrossirius. Images were obtained from light microscopy and digitally processed and "blindly" analyzed using Image Pro-Plus Software. For statistical analysis we used Spearman's coefficient. Differences were considered statistically significant if P≤0.05. RESULTS: the ossicular chain was involved in 65 cases. The incus was the most frequently affected bone, followed by the stapes and the malleus. When the Spearman's coefficient was employed considering ossicular chain change degree with patient's age by the time of surgery, perimatrix thickness and histological degree of inflammation, correlations were not established. CONCLUSION: Our findings indicate that ossicular chain changes are practically universal when a cholesteatoma is present. We didn't find correlations related with bone erosion and cholesteatoma's histological findings.
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Humanos , Adolescente , Adulto , Criança , Colesteatoma da Orelha Média/patologia , Ossículos da Orelha/parasitologia , Otite Média/patologia , Fatores Etários , Doença Crônica , Estudos Transversais , Colesteatoma da Orelha Média/cirurgia , Colesteatoma da Orelha Média/complicações , Ossículos da Orelha/cirurgia , Otite Média/cirurgia , Otite Média/etiologia , Índice de Gravidade de DoençaRESUMO
Background: The diagnosis of lesions of ossicular chain plays a vital role in ear surgery, especially surgery for hearing rehabilitation.Objective: The purpose of this study was to assess the value of the virtual CT of the temporal bone in the diagnosis of lesions of the ossicular chain. Subject and Method: A prospective study was carried out in the National ETN Hospital. 117 patients between 15 and 54 years of age with suspected ossicular chain lesions underwent CT of the temporal bone before surgery. Result: Using CT of the temporal bone identified 90 patients (76.92%) with ossicular chain lesions, 27 patients (23.08%) without ossicular chain lesions. The positive diagnosed value of CT of the temporal bone was rather high with p=0.87. The negative diagnosed value of CT was p=0.76.The rate of false diagnosis was 0.24. Conclusion: CT of the temporal bone proved to be effective for diagnosing ossicular erosion. This study demonstrates the value of virtual CT of the temporal bone in the diagnosis of the ossicular chain with p-value = 0.84.
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Objective Using curved planar reformation(CPR)to delineate the ossicular chain(OC)in one image and evaluate its clinical application. Methods HRCT of temporal bone was performed in 122 cases(165 ears).The CPR of OC was then performed.The main parameters were as follow:collimation 0.5mm,pitch 0.875,reformation interval 0.2~0.3mm,reformation matrix 1024?1024.Results (1)CPR of normal OC were performed on 80 ears,the three ossicles and its joints could be showed on one image clearly.(2)Clincal application(72cases):in 39 cases of temporal bone trauma,OCs were normal in 21 cases and abnormal in 18 cases.Subluxation or dislocation of malleoincudal joint(MIJ)(5,5) and incudostapedial joint(ISJ)(5,6),dislocation of MIJ and ISJ with rotation of incus(1 case),fracture of manubrium of malleus(1 case) were found respectively.In 16 cases of external auditory canal dysplasia(EACD),the most commonly associated type of OC deformity was absence of manubrium of malleus(10 cases)。Absence of OC associated with coarctation of middle ear cavity(3 cases) and fusion of the malleus and incus associated with absence of long process of incus represented in 1 case.Congenital ossicular anomalies without associated EACD were found in 2 cases.The long processes of the incus of both side were absent in 1 case.Incudostapedial disconnection was demonstrated in 1 case due to improper development of the long process of the incus.In 15 cases of chronic otitis media(COM),6 cases were complicated cholesteatoma.Destruction of OC was demonstrated in 6 cases.Conclusion CPR of OC with multislice spiral CT is an effective method in the diagnosis of conductive hearing loss.
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Objective: To analyze the diagnosis and therapeutic effect of the middle ear abnormalities.Method: 65 ears from 1967 to 1996 were reviewed. The degrees of the ossicular abnormalities were analyzed,operative effect were valued. Result:In the 65 ears,incus abnormalities was 57 ears (87.7%),stapes was 55 ears(84.6%), mixed malformation was dominant. 47 ears were operated with ossicular chain reconstruction. 44 ears(93.6%) had hearing improvement, 32ears (68.1%) had obviously improvement (>20 dB). They werefollowed up over one year, 44 ears had steadily heraring and had not any complications. Conclusion:If diagnosisand interference were all proper, operation would obtain good result.
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Objective (1)To observe the imaging features of the normal anatomic structures of middle ear using CT virtual endoscopy.(2)To study morphologic changes of ear ossicles and auditory ossicular chain of patients with conductive deafness.Methods CTVE of the auditory ossicular chain was performed on GE Hispeed CT/I with 1.0 mm slice thickness at pitch 1, bone algorithm, voltage 140 kV, electric current 170~220 mA, 9.6 cm field of view.Results CTVE could clearly demonstrate the normal auditory ossicular chain and its anatomic details. The demonstration rate of CTVE images in detecting the malleus-incus joint was 100%(162/162), in detecting "L"type incus-stapes joint was 80%(130/162), in detecting the anterior and posterior stapes footplate was 73%(121/162); CTVE could well display the destruction of auditory ossicular chain in otitis media and cholesteatoma and could acurately show the malformation of the auditory ossicular chain.Conclusion CTVE can quickly, non-invasively, three-dimensionally display the middle ear auditory ossicular chain, can provide direct and reliable imaging information for discovering the cause of a disease of conductive deafness.