Congenital Malformations of the Temporal Bone

Objective: To evaluate the auditory efficacy of Bonebridge implantation in patients with bilateral congenital malformation of external and middle ear. Methods: Eleven cases (6 males and 5 females) had unilateral Bonebridge implantation. The age ranged from 8 to 26 and the average age was 16.9. Seven to ten days after operation, the first fitting was undergone. In acoustic sound field, the average auditory thresholds were respectively measured for unaided ears and Bonebridge implanted ears by pure tone auditory (PTA, 0.25, 0.5, 1, 2 and 4 kHz). For the group over 12-year-old, MSTM was applied to evaluate speech discrimination score (SDS). For the other cases, MLNT was used as the test material. The auditory efficacy post Bonebridge implantation would be analyzed and evaluated by comparing the differences between unaided ears and Bonebridge implanted ears. Results: The bone conduction audibility threshold after Bonebridge implantation was as well as the preoperative. The auditory threshold with Bonebridge aided was improved to 25-35 dB HL, when compared to that of the unaided ears in the sound field. The SDS in the group over 12-year-old was improved about 50%; the efficacy was slightly limited for the other two cases (both less than 12 years old). Statistical analysis showed that there were significant differences between unaided ears and Bonebridge implanted ears in the sound field and SDS(P<0.05). Conclusions: The auditory efficacy of Bonebridge is significant and noticeable in patients with bilateral congenital malformation of external and middle ear. Bonebridge provides a new and effective way for patient with congenital malformation of external and middle ear to reconstruct hearing.

Cochlear implantation (CI) is a safe and beneficial surgery for children with congenital inner ear malformations, with the exception of cochlear nerve aplasia. The combination of microtia with middle and inner ear abnormalities is extremely uncommon and sufficiently severe to make a surgical approach to the cochlea difficult. We report herein the case of a 2-year-old girl who presented with profound bilateral sensorineural hearing loss, congenital aural atresia, microtia, and inner ear malformations. High-resolution computed tomography revealed poor development of the bilateral middle ear spaces, absence of the incus and stapes, aberrant courses of facial nerves, aplastic lateral semicircular canals, and covered round windows. With intraoperative imaging assistance, sequential bilateral CI was performed using a transmastoid approach with no complication. We propose that CI is feasible in patients with severe external and middle ear malformations. However, major malformations increase the risk of complications. As the facial nerve and cochlea are difficult to locate due to the lack of important anatomical landmarks, detailed planning and adequate preparation, including review of the preoperative imaging data, and the use of facial nerve monitoring and intraoperative imaging are very important. In addition, experienced surgeons should perform CI to ensure the success of the operation.

Hypothesis: There is a positive correlation between type and intensity of combined congenital ear malformations and results of surgical reconstruction. Background: Combined congenital malformations of external and middle ear pose a lot of surgical problems and demand adequate skill and planned, fractioned therapy. The goals of these operations are: limited number of operations with minimal complications, well cosmetic result, hearing improvement and easier use of hearing aid, removal of congenital cholesteatoma, preservation of labyrinth and facial nerve. Methods: The aim of this work is to present the experience in treating patients with combined malformations of external and middle ear. In the period between 1992 and 2001 seventeen patients with this type of congenital malformations were operated. Classical dilemma who operates first, plastic surgeon or otosurgeon is solved here by complete otosurgical treatment with reduced number of operations. Results: Totally 36 operation was performed, two reoperations were made in four patients, and also three operations in three patients for the reconstruction of deformity of auricle. In seven patients costal rib cartilage was used for auricular framework. Reoperations were done during the course of auricular reconstruction (14 operations), or because of meatal restenosis (five operations), or cartilage graft necrosis (one case). Atresia was adequately solved in 14 patients, while in three cases connective tissue meatal restenosis was found. The results of reconstruction of auricular malformation were aesthetically good in 13 patients and sufficient in four patients. Conclusion: We found positive correlation between external ear and middle ear deformity, and the results of reconstruction, as well. Two thirds of patients have hearing threshold level under 30 dB, while the threshold in other patients is 30-40 dB. Residual airbone gap amounting about 20 dB was universally present.

Assessing outer and middle ear status in neonates and young infants is a challenging task for audiologists and medical professionals. Although standard tests such as 226-Hz tympanometry are used successfully to evaluate the function of the outer and middle ear in older children and adults, they are not diagnostically accurate for young infants less than 7 months of age (Kei & Zhao, 2012). Sweep frequency impedance (SFI) is a new emerging technique which can provide useful information about the dynamic behaviour of the outer and middle ear in neonates and young infants. From this dynamic behaviour, the resonance frequency and mobility of the outer ear and middle ear in young infants can be measured. While there are limited case reports and pilot studies exploring the use of SFI with neonates (Murakoshi et al., 2013; Murakoshi, Zhao, & Wada, 2012), further systematic investigation in the clinical applications of SFI in neonates and young infants is essential before SFI can be used as a diagnostic tool for detecting conductive conditions in this population. The present research study aimed to (1) establish normative SFI data for healthy Australian neonates, (2) measure the effect of ear canal static pressure on the dynamic behaviour of the outer and middle ear in healthy newborns, (3) investigate the developmental characteristics of SFI measures in infants from birth to 6 months of age, (4) compare SFI measures obtained from healthy Australian Aboriginal infants with that obtained from Caucasian infants, and (5) evaluate the test performance of SFI against individual and test battery reference standards. Normative SFI data were developed for healthy Australian neonates (Chapter 2). The results revealed two regions of resonance, with the first resonance occurring at 287 Hz, possibly related to outer ear canal wall movement, and the second resonance occurring at 1236 Hz, possibly related to middle ear resonance. The effect of ear canal static pressure on the dynamic behaviour of 122 ears of 86 healthy newborns and 10 ears of 10 newborns with middle ear dysfunction was studied using SFI (Chapter 3). Application of either a positive or negative static pressure to the ear canal of healthy newborns increased the resonance frequency but decreased the mobility of the outer ear and middle ear. In contrast, in ears with middle ear dysfunction, the resonance of the middle ear was absent with no mobility of the middle ear under various static pressures. Application of negative pressure up to minus 200 daPa resulted in collapsed ear canals in more than 90% of ears. Developmental characteristics of SFI data were obtained from 83 healthy infants from birth to 6 months using a cross-sectional study design (Chapter 4). Mean resonance frequency of the outer ear increased from 279 Hz at birth to 545 Hz at 4 months, while the mobility of the outer ear decreased with age. In comparison, the mean resonance frequency and mobility of the middle ear did not change significantly with age from birth to 6 months. Despite Australian Aboriginal children having a higher prevalence of otitis media than Caucasian children, very few studies have compared the acoustic-mechanical properties of the outer and middle ear between Aboriginal and Caucasian neonates. SFI data from 40 ears of 24 Aboriginal neonates were compared with that from 160 ears of 119 Caucasian neonates (Chapter 5). Despite passing the test battery, Aboriginal neonates had significantly lower resonance frequencies of the outer and middle ear than Caucasian neonates. Furthermore, 22.5% of Aboriginal neonates showed no middle ear resonance, indicating the possibility of subtle conductive conditions not detected by the test battery. The predictive accuracy of SFI in identifying conductive conditions in neonates against 4 single reference standards [automated auditory brainstem response (AABR), high frequency tympanometry (HFT), transient evoked otoacoustic emissions (TEOAE), and distortion product otoacoustic emissions (DPOAE)] and 5 test batteries standards (HFT+DPOAE, HFT+TEOAE, DPOAE+TEOAE, DPOAE+AABR and TEOAE+AABR) was evaluated (Chapter 6). The predictive accuracy of SFI was highest when measured against the HFT+DPOAE test battery reference standard, with an area under the receiving operating characteristic curve (AROC) of 0.87. The corresponding sensitivity was 86% and specificity was 88%, with positive likelihood ratio of 7 and negative likelihood ratio of 0.2. Since SFI is an accurate and valid measure of outer and middle ear function in neonates, it may be used for both screening and diagnostic assessments in neonates. In conclusion, this thesis has not only confirmed the feasibility of testing neonates and young infants using the SFI technique, but it has also expanded the clinical application of SFI to detecting conductive conditions in this population. While the SFI technology has shown promising results when assessing young infants, further research is needed to improve the instrumentation and test protocol for screening and diagnostic purposes.

Teratoma is a germ cell tumor, which is rare behind the ear. We described a rare case of retroauricular teratoma accompanied with congenital malformation of external and middle ear and cholesteatoma of middle ear in a 13-years-old girl. Congenital microtia and ankylotia of right ear was found since childhood, suppuration occurred repeatedly behind the right ear 1 year ago. Temporal bone CT and MRI scan revealed congenital malformation of middle ear and cholesteatoma of middle ear. Cystic mass containing a tooth was found intraoperatively. The pathological results showed that it was benign cystic teratoma. It showed no evidence of recurrence on the patient during 3 months follow-up.

US and MRI anatomy of fetal ear

Objective: To analyze the clinical characteristics and appropriate surgical procedures, and discuss the classification of congenital middle ear malformation. Methods: All cases were from the Center of Otorhinolaryngology, the Sixth Medical Center of Department of PLA General Hospital. All of these cases, including 26 male patients (ears) , 10 female patients (11 ears) , aged from 7 to 57 years old, had normal external auditory canal, tympanic membrane, conductive hearing loss, type A tympanogram and negative Gelle's test. Tympanoplasty was performed in all cases. The deformity was classified to three types,i.e., Type I (stapes foot plate mobility): Ⅰa, ossicular chain deformity with normal stapes suprastructure; Ⅰb, ossicular chain deformity with abnormal stapes suprastructure; Type Ⅱ (stapes foot plate fixation): Ⅱ a,normal ossicular chain, Ⅱ b, ossicular chain malformation; and Type Ⅲ: vestibular window osseous atresia or undeveloped, or with round window atresia. The malformation of type Ⅱ and Ⅲ may be accompanied with abnormal facial nerve. In addition, the papers on middle ear malformation published from 1982 to 2017 were analyzed retrospectively. The clinical data of 451 ears malformation were summarized. Results: According to the revisional classification criteria in 37 ear samples from our hospital, 20 ears were type I. 6 type Ⅰa cases were used PORP (partial ossicular replacement prosthesis) to reconstruct the ossicular chain; 14 type Ⅰb cases were used TORP (total ossicular replacement prosthesis) to reconstruct the ossicular chain. For the 5 ears of type Ⅱ, 2 of which were type Ⅱ a and 3 were type Ⅱ b. 4 ear samples of type Ⅱ were implanted with Piston ossicular prosthesis, 1 was implanted with TORP in which the ossificated foot plate was removed with periosteum preserved. 12 ear samples were type Ⅲ, with vestibular window osseous atresia, facial nerve malformation, and stapes suprastructure malformation. The pistons ossicular prosthesis were implanted in vestibular window in 3 ears with facial nerve covering vestibular window partially. The surgery had to be given up in 5 ears, and TORP was implanted in 4 ears at the opening with preserved periosteum at the beginning of the tympanic scala because of facial nerve covering vestibular window totally. 30 ears with complete follow-up data had no sensorineural hearing loss and the average air-bone conduction decreased 23.3±10.7 dB (P<0.05).There were 234 ears of type Ⅰ in 451 ears of congenital middle ear malformation reported in the literature. 113 of which were type Ⅰa, the basic surgery was ossicular chain shaking and artificial or autogenous PORP implantation. Type Ⅰb was 121 ears, with autogenous or artificial TORP and PORP. Type Ⅱ was125 ears, including type Ⅱa 22 ears, Ⅱb 60 ears, and no subclassification for 43 ears. The surgery of type Ⅱ was the same as otosclerosis. The vestibular window atresia of type Ⅲ was 92 ears, the surgery of 17 ears had to be abandoned, the other ears underwent vestibular window, promontory or semicircular canal opening to reconstruct hearing with Piston, autogenous or artificial TORP. Conclusion: Referring to the classification of congenital middle ear malformation combining with appropriate surgical materials and methods, otologists can better understand and choose appropriate surgical method to the middle ear malformation.

Classification of facial nerve aberration in congenital malformation of middle ear: Implications for surgery of hearing restoration

Deafness gene variants play a key role in inner ear malformations. However, the relationship between congenital middle ear malformations and common deafness genes (GJB2, SLC26A4, and mtDNA) in profound sensorineural hearing loss (SNHL) child patients remains poorly investigated. Here we showed that there was no statistical significance in the total mutation frequency of the three common deafness genes in the middle ear malformation group (21.2%, 41/193) in comparison with the normal middle ear and inner ear group (21.0%, 116/553) (χ2 = 0.0061, p = 0.940). Moreover, the mutation ratio of GJB2 and SLC26A4 in the middle ear malformation group (18.7%, 36/193; 2.6%, 5/193) was not significantly different from that in the normal middle ear and inner ear group (17.7%, 98/553; 2.4%, 13/553) (χ2 = 0.084, p = 0.772; χ2 = 0.0000, p = 1.000). The mutation ratio of GJB2 235delC and GJB2 79G>A in the middle ear malformation group (8.8%, 17/193; 8.8%, 17/193) was almost the same to that in the normal middle ear and inner ear group (8.6%, 48/553; 6.7%, 37/553) (χ2 = 0.0030, p = 0.957; χ2 = 0.9556, p = 0.328). The high jugular bulb subgroup analysis also showed the same results. Our findings suggested that GJB2, SLC26A4, and mtDNA mutations might not be related to the middle ear malformations in profound SNHL child patients. Anat Rec, 303:594-599, 2020. © 2019 American Association for Anatomy.

Objective To discuss the safety and efficacy of simultaneous procedures of vibrant soundbridge implantation and auricular reconstruction with congenital external and middle ear malformation. Methods This is a retrospective study, including 6 patients, 5 boys and 1 girl, aged 7-12 years. All patients received simultaneous operations of vibrant soundbridge implantation and auricular reconstruction. The mean preoperative air conduction threshold was 64.8 dB HL at 0.5, 1, 2, and 4 kHz. The VSB was placed in the third stage of auricle reconstruction, if the soft tissue expansion was performed; otherwise, the VSB was implanted in the second stage. The satisfaction with reconstructed auricle, surgical complications, hearing improvement and speech discrimination scores were evaluated 6 months after surgery. Results All patients and their families reported satisfaction with their reconstructed auricle. There was no complications, including cartilage framework exposion, infection, hematoma, skin flap necrosis, facial paralysis, tinnitus, vertigo or others. Post-operatively, mean VSB-aided hearing threshold was 36.7 dB HL, which was reduced by 28.1 dB HL. The mean speech discrimination scores measured in a sound field with a presentation level of 65 dB SPL and 80 dB SPL were improved. Conclusions The simultaneous operations of auricle reconstruction and Vibrant Soundbridge implantation is an alternative method for patients with congenital microtia and atresia. Key words: Hearing loss, conductive; Middle ear implant; Congenital microtia

To evaluate hearing outcomes and postoperative complications among patients with middle and external ear malformations undergoing active middle ear implantation with Vibrant Soundbridge® (VSB). Review of the literature. Studies published in English, Portuguese, or Spanish at the following databases: PubMed, MEDLINE, Scopus, Web of Science, EMBASE, and Cochrane Library were searched. The search strategy yielded a total of 141 potentially relevant studies. Of these, ten were included in this analysis. The mean preoperative air conduction threshold was 66.7 ± 6.2 dB. The mean air-bone gap was 46 ± 7.7 dB. VSB implantation resulted in mean hearing gain of 40.5 ± 7.1 dB in the air-conduction thresholds among the evaluated frequencies. The speech recognition index if the Floating Mass Transducer (FMT) was placed in the short process was 86.0% ± 9.6%, with significant difference when compared to long process coupling (p = 0.035) and the round window coupling (p = 0.048). Bone conduction thresholds did not worsen in any of the studies included in the present review. VSB implantation resulted in a mean hearing gain of 40 dB at air conduction thresholds.

The mammalian ear is a complex structure divided into three main parts: the outer; middle; and inner ear. These parts are formed from all three germ layers and neural crest cells, which have to integrate successfully in order to form a fully functioning organ of hearing. Any defect in development of the outer and middle ear leads to conductive hearing loss, while defects in the inner ear can lead to sensorineural hearing loss. This review focuses on the development of the parts of the ear involved with sound transduction into the inner ear, and the parts largely ignored in the world of hearing research: the outer and middle ear. The published data on the embryonic origin, signalling, genetic control, development and timing of the mammalian middle and outer ear are reviewed here along with new data showing the Eustachian tube cartilage is of dual embryonic origin. The embryonic origin of some of these structures has only recently been uncovered (Science, 339, 2013, 1453; Development, 140, 2013, 4386), while the molecular mechanisms controlling the growth, structure and integration of many outer and middle ear components are hardly known. The genetic analysis of outer and middle ear development is rather limited, with a small number of genes often affecting either more than one part of the ear or having only very small effects on development. This review therefore highlights the necessity for further research into the development of outer and middle ear structures, which will be important for the understanding and treatment of conductive hearing loss.

The maturation of the external and middle ear in the human infant has significant effects on the interpretation of measured ear-canal responses to acoustic stimuli. A tutorial section is presented of power-based response functions, accompanied by a hierarchy of stimulus specifications contrasting pressure-based and power-based responses. An experimental section follows on reflectance tympanometry, the aims of which are to introduce and assess the feasibility of the technique and to discuss implications for tests of hearing development. A tympanometric measurement of admittance is used with an estimate of ear-canal area to calculate a so-called reflectance tympanogram as a function of frequency and static pressure in the ear canal. Selected results on 226 Hz reflectance tympanograms are reported for normal-hearing adults and for infants of age 3 to 6 mo with both normal and flat 226 Hz admittance tympanograms. A multifrequency reflectance tympanogram is reported for an adult. Measured at ambient ear-canal pressure, the acoustic external- and middle-ear responses of infants of age 1 to 6 mo are compared with those of adults. The admittance level is influenced by the ear-canal area, the interplay of compliant- and inertance-controlled effects in the middle ear, and the presence of losses. Ear-canal area is a major factor in distinguishing infant from adult responses. Energy reflectance provides a measure of middle-ear power transmission that is approximately independent of probe placement in the ear canal and that varies with maturation. These power-based responses, measured at ambient pressure, are contrasted with tympanometric measurements. Reflectance tympanometry is defined and easily measured in infants and adults. Some infants with flat 226 Hz tympanograms have energy reflectance in the normal range at higher frequencies (2 to 4 kHz). Acoustic measurements of power-based responses in the ear canal-reflectance, admittance, and impedance-provide insight into the maturation of the external and middle ear. Reflectance tympanometry tests the relative accuracy underlying the tympanometric measurement of compensated eardrum admittance and may have clinical utility.

It is well known that the incidence of carcinoma in the external and middle ear is very low and that the prognosis is poor, especially for middle ear carcinomas.During the past 15 years, 11 patients with carcinoma of the middle or external ear have been treated in the Department of Otolaryngology of Hokkaido University Hospital. Seven carcinomas were in the external auditory canal and four in the middle ear. The histopathologic diagnosis was squamous cell carcinoma in eight, and adenoid cystic carcinoma in three patients. Therapy was mainly a combination of irradiation and surgical resection. Three patients also received CDDP.Our results revealed that the prognosis for external ear carcinoma is much better than for middle ear carcinoma. All four patients with middle ear carcinoma died, but five of the seven patients with external ear carcinoma are alive and free of the disease, at least one and a half year after surgery.Carcinoma of the external ear canal tended to show radial extension, involving the soft tissues adjacent to the canal rather than extending longitudinally towards the middle ear.The principal factor in the poor prognosis of middle ear carcinoma is ascribed to the destruction of the skull base, while that of the external auditory canal is deep invasion of the soft tissue around the canal.

On the basis of strong research, universal newborn screening should be performed before age 1 month with repeat or follow-up testing for those who do not pass performed before age 3 months and intervention started before age 6 months. On the basis of strong research and consensus statement, tympanostomy tubes should be considered for individuals with bilateral persistent middle ear effusion for 3 months or greater and a documented conductive hearing loss. On the basis of consensus statement, all children with suspected hearing loss should have an age appropriate hearing test. On the basis of strong research, the most common form of congenital hearing loss is genetic. Most of this is nonsyndromic hearing loss.