Selection of inner ear fenestration strategy and surgical effect of patients with oval window atresia accompanied by facial nerve aberration

Objective: To conclude the clinical features and the postoperative efficacy of congenital middle ear malformation treated with Malleostapedotomy (MS), and to explore the security and effectiveness of MS surgery. Methods: The clinical data of 17 patients (18 ears) with congenital middle ear malformation undergoing MS procedure were analyzed. There were 10 males (11 ears) and 7 females (7 ears), aged from 7 to 48 years. The imaging examination, pure-tone audiometry, intraoperative findings and postoperative hearing improvement of these patients were analyzed and summarized, and software SPSS23.0 was used for statistical analysis. Rusults All the 17 patients (18 ears) presented with hearing loss since childhood on the affected sides. Preoperative high resolution CT (HRCT) of the temporal bone revealed definite malformations in 9 ears (6 ears with incus long process dysplasia and 3 ears with anterior and posterior crus dysplasia). Before surgery, the mean bone conductive hearing threshold at 500, 1 000, 2 000 and 4 000 Hz was (15.6±10.2) dB HL, the mean air conductive hearing threshold was (60.6±9.7) dB HL, and the mean air-bone gap was (45.0±8.9) dB. During the surgery, all 18 ears were found to be accompanied by absence or hypoplasia of incus long process. 12 ears had stapes fixation, 6 ears had oval window atresia. All patients were treated with MS procedure by using Piston. The patients were followed up for 3 months to 1 year. The mean bone conductive hearing threshold was (14.7±8.8) dB HL. The mean air conductive hearing threshold was (37.7±11.6) dB HL, and the mean air-bone gap was (23.0±8.0) dB. There were statistically significant differences in the mean air conductive hearing threshold and mean air-bone gap before and after surgery (P<0.05). While there were no statistically significant differences in the mean bone conductive hearing threshold before and after surgery (P=0.550). Conclusions: MS procedure is safe and reliable in patients with congenital middle ear malformation of incus long process dysplasia, stapes fixation or oval window atresia. HRCT is useful in evaluating the major deformity of ossicular chain and facial nerve deformity. However, it is not enough to evaluate the joint of incus-stapes and oval window atresia. MS surgery in middle ear malformation requires advanced surgical experience and skills. The hearing improvement can be significant, even though some air-bone gap after surgery exist.

Isolated oval window atresia (OWA) is a rare cause of congenital conductive middle ear deafness and may be overlooked owing to the normal appearance of the external ear. This anomaly has been previously described, although the published numbers with both imaging and surgical findings are few. Our aim is to correlate the imaging features of OWA with intraoperative findings. This is a single-centre retrospective evaluation of patients who were diagnosed with OWA and who received surgery from January 1999 to July 2006. No new case was diagnosed after 2006 to the time of preparation of this manuscript. High resolution computed tomography (HRCT) imaging of the temporal bones of the patients were retrospectively evaluated by 2 head and neck radiologists. Images were evaluated for the absence of the oval window, ossicular chain abnormalities, position of the facial nerve canal, and other malformations. Imaging findings were then correlated with surgical findings. A total of 9 ears in 7 patients (two of whom with bilateral lesions) had surgery for OWA. All patients had concomitant findings of absent stapes footplate with normal, deformed or absent stapes superstructure and an inferiorly displaced facial nerve canal. HRCT was sensitive in identifying OWA and associated ossicular chain and facial nerve abnormalities, which were documented surgically. OWA is a rare entity that can be diagnosed with certainty on HRCT, best visualised on coronal plane. Imaging findings of associated middle ear abnormalities, position of the facial nerve canal, which is invariably mal-positioned, and associated deformity of the incus are important for presurgical planning and consent.

The purpose of this study is to categorize anomalous tympanic facial nerve (FN) on high-resolution computed tomography (HRCT) and to determinate the significance of associated temporal bone anomalies and congenital syndromes without microtia in patients with hearing loss. A retrospective analysis of HRCT findings in 30 temporal bones in 18 patients with anomalous FN was performed. Abnormalities of the tympanic FN were categorized as follows: category 1: FN medially positioned, but above the oval window; category 2: FN in the oval window niche; and category 3: FN below the oval window. Potential associated findings that were assessed included stapes abnormalities, oval window atresia, and inner ear anomalies, as well as the presence of a known congenital syndrome with hearing loss. The most common type of anomalous tympanic FN was category 1 (67%, n = 20), following by group 2 (20%, n = 6) and group 3 (13%, n = 4). Stapes anomalies were detected in 77% of temporal bones (n = 23), oval window atresia was detected in 43% of temporal bones (n = 13), and inner ear anomalies were detected in 70% of temporal bones (n = 21). Anomalous tympanic facial nerves in temporal bone with conductive hearing loss were often (60%) not associated with oval window atresia. The combination of aberrant tympanic FN and inner ear anomalies was significantly (P = .038) associated with a known congenital syndrome (6 patients), including CHARGE syndrome, oculo-auriculo-vertebral spectrum, Pierre-Robin sequences, and Down syndrome. Therefore, an anomalous tympanic FN in conjunction with inner ear anomalies appears to be a biomarker for certain congenital syndromes with hearing loss in the absence of microtia.

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.

Isolated congenital middle ear malformation (CMEM) contributes significantly to congenital hearing loss and growth problems. This study aims to compare 0.1-mm isotropic ultra-high-resolution CT (U-HRCT) and conventional high-resolution CT (HRCT) for assessing isolated CMEM, using surgical exploration as the standard. This single-center retrospective study included patients with surgically confirmed isolated CMEM who underwent U-HRCT or HRCT from January 2015 to April 2025. Middle ear abnormalities were identified based on operative outcomes and 4 subtypes were classified via the Teunissen standard. Two neuroradiologists blinded to surgical outcomes reviewed CT images for 10 subtle structural abnormalities and specific subtypes. The comparison of U-HRCT and HRCT in terms of interobserver and intraobserver agreement and detection of structural abnormalities and subtypes of CMEM were analyzed. The U-HRCT and HRCT groups included 61 patients (69 ears) and 37 patients (44 ears), respectively. U-HRCT exhibited significantly higher interobserver and intraobserver agreement and stronger concordance with surgical findings for all 10 abnormalities compared with HRCT. It also showed superior diagnostic sensitivity for CMEM (100.0% versus 90.9%; P = .013) and outperformed HRCT in differentiating clinical subtypes (0.774 versus 0.352; P<.001). U-HRCT achieved accuracies exceeding 0.85 in identifying all abnormalities and outperformed HRCT in detecting specific abnormalities including abnormal long process of the incus, lenticular process, abnormal stapes superstructure, stapes footplate fixation, and oval window atresia (P < .05). Isotropic 0.1-mm U-HRCT significantly outperforms conventional HRCT in diagnosing CMEM, differencing subtypes, and detecting subtle abnormalities, supporting its clinical superiority for precise preoperative evaluation.

To compare preoperative temporal bone high-resolution computed tomography (HRCT) readings to intraoperative findings during exploratory tympanotomy for suspected cases of isolated congenital middle ear malformations (CMEMs) and summarize the malformations that can and cannot be diagnosed with HRCT. A retrospective study was conducted. All cases were confirmed as isolated CMEMs during surgery. Detailed clinical records were reviewed, with a focus on imaging and surgical findings. One hundred and thirty-two patients and 145 ears were reviewed. Ninety cases (62.1%) could be identified as isolated CMEMs and at least one as middle ear anomaly using preoperative HRCT. Fifty-five cases (37.9%) were reported to be completely normal and the patients underwent exploratory tympanotomy to determine the final diagnosis. Stapes fixation, either alone or associated with other ossicular chain anomalies, contributed to 53.1% of the cases. Most cases of aplasia or dysplasia of the ossicular chain, for example, aplasia/dysplasia of the long process of the incus, aplasia of the stapes' superstructure, and atresia of the oval window were easily identified in preoperative HRCT. However, fixation of the ossicular chain can be elusive in HRCT, and exploratory tympanotomy is needed for a definitive diagnosis. HRCT provides helpful preoperative clinical information in CMEM and may obviate the need for middle ear exploration in some cases. The negative findings (anomalies that are difficult to identify through preoperative HRCT) and the positive findings (anomalies that are relatively easy to identify through preoperative HRCT) were summarized.

Introduction: Since in 1995 the first case of absence of stapes was described, several cases were reported. However, its etiology remains unknown. Some authors suggest a genetic cause, without excludingthe possibility of embryopathy due to infections or chemical agents. The existence of an associated palatal cleft, in this case, reinforces the hypothesis of a multifactorial origin. Objective: Describe a rare condition in order to know how to suspect it. This condition is frequently associated with facial nerve malposition, that difficult the surgery and so, the most frequenttreatment is providing hearing aids or a bone anchored hearing aid. Case report: We present a case of a 10 years old girl who complains of left hearing loss since childhood, accompanied by tinnitus and frequent left ear otorrhea episodes. We studied symptoms, complementary exams, treatment and course. Discussion and conclusions: A middle ear malformation should be suspected with the presence of a history of conductive hearing loss since birth or more frequently between the 7 and 12years old, fixed-type, which often affects conversational or low frequencies, which are more intense than other acquired hearing loss, with no history of ear infections or without improvement despite different kinds of treatments, and witha family history of hearing loss. Conclusion: Congenital absence of stapes and oval window associated with anomalous course of the facial nerve is a rare entity. It presents as a conductive hearing loss non-progressive with 60 dB tone airthreshold, often presented during childhood. Diagnosis is based on clinical suspicion by a correct medical history and audiological examination, confirmed by Computed Tomography (CT) scan. The anomalous course of the facial nerve supports the diagnosis and guides treatment. Initial treatment with hearing aids provides good hearing gain with adequate adaptation.

Facial nerve abnormalities and congenital middle ear malformations originate in similar developmental stages and are often concomitant. Preoperative recognition of such a condition is desirable to prevent any damage, but it is often difficult. Here, we report two cases of middle ear malformations associated with facial nerve abnormalities, describe the computed tomography (CT) appearance, and discuss its preoperative detectability. Case 1 was a 40-year-old female with a facial nerve abnormality associated with stapes ankylosis. She underwent stapes surgery. The facial nerve was hanging over the footplate of the stapes. Case 2 was a 32-year-old female with a facial nerve abnormality associated with stapes ankylosis. She underwent an exploratory tympanotomy. The facial nerve was branched. The branches emerged from the incudo-malleolar joint, ran between the chorda tympani nerve and the incus, and ran into the temporal bone inside the canaliculus chorda tympani. For both cases, the facial nerve branches were detectable with high-resolution CT (HRCT) in the mastoid segment and were confirmed during surgery. For Case 2, the facial nerve was also visible with HRCT as soft tissue shadows in the tympanic portion on the lateral side of the stapes. These two cases highlighted the critical role of preoperative CT imaging in detecting subtle features of facial nerve anomalies, such as nerve branching in the mastoid segment or soft tissue shadows around ossicles.

BACKGROUND:The aim of this study is to evaluate the indications and efficacy of facial nerve decompression through an endoscopic transcanal approach for patients with traumatic facial paralysis.Methods:This single-center retrospective study included 11 patients with traumatic facial paralysis from February 2018 to April 2019. We compared the facial nerve and auditory function before and after operation so as to reveal the feasibility and effect of the surgical approach.Results:All 11 patients have successfully received facial nerve decompression through endoscopic transcanal approach. Facial nerve function was objectively evaluated by electroneurography test and House-Brackmann facial nerve grading system. All patients were graded HB-VI with electroneurography ≥ 95% before surgery. The recovery of facial nerve function was good (HB-I or II) (90.9%) a year after surgery with only one case (9.1%) for HB-III. Preoperative high-resolution computed tomography showed that 1 patient had ossicular chain interruption, which was confirmed during operation. Meanwhile, 2 patients with air-bone gap >35 dBHL and whose computed tomography failed to diagnose were found with ossicular chain interruption during operation. The air-bone gap of patients with normal ossicular chain connection was all <30 dBHL. The average air-bone gap was reduced from 27.5 ± 10.1 dBHL to 7.8 ± 3.3 dBHL after operation.Conclusion:Preoperative high-resolution computed tomography combined with localization test can accurately estimate the location of facial nerve injury. Facial nerve decompression through endoscopic transcanal approach can decompress the geniculate ganglion to pyramidal segment of facial nerve, which is suitable for patients with traumatic facial paralysis of this segment. In addition, air-bone gap >35 dBHL may indicate the ossicular chain interruption when it is difficult to be completely judged by high-resolution computed tomography.

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

View Video S1 Laryngoscope, 131:E961–E965, 2021

Oval window atresia: A novel surgical approach and pathognomonic radiological finding

Dear Editor,&#x0D; &#x0D; The tympanic membrane and the ossicular chain contribute roughly 28 dB in hearing gain. In chronic suppurative otitis media, loss of tympanic membrane and lysis of the ossicular chain are significant causes of hearing loss.1 Through the years, hearing impairment has been augmented using various devices such as ear trumpets, carbon hearing aids, vacuum tube and transistor hearing aids, bone anchored hearing aids, and cochlear implants.2 This case report describes how a cotton wick was used to amplify sound.&#x0D; &#x0D; Case Report&#x0D; A 65-year-old man consulted for hearing loss. He had a childhood history of recurrent ear discharge and hearing loss and was diagnosed with chronic suppurative otitis media. At age 55, he underwent tympanomastoidectomy of the left ear. While surgery stopped the left ear discharge, there was complete hearing loss in this ear. For this reason, he opted not to have surgery on the right ear. There was subsequent recurrent ear disease of the right ear. He would clean his ear with a cotton wick and apply antibiotic drops during bouts of ear discharge. He observed that leaving the ear wick with a few drops of topical otic preparations (polymyxin-neomycin-steroid or ofloxacin) would lessen the frequency of ear discharge and improve his hearing. He found that morning application and positioning of the cotton wick in his right ear using tweezers and a toothpick allowed him to hear adequately to conduct his daily activities as an architect. (Figure 1, 2) The fear of hearing loss from another surgery, cost of a commercial hearing aid, and great utility of a simple cotton wick made him continue his practice for these ten years.&#x0D; Examination of the right middle ear without the cotton wick showed thickened mucosa, absent malleus and incus structures, a patent Eustachian tube and a near – total tympanic membrane perforation. There was no keratinous material or foul smelling discharge. (Figure 3) Pure tone audiometry confirmed that with the cotton wick, the right air-bone gap decreased at 500 hz, 1kHz, 2Kh and 4KHz by 30db, 40dB, 35dB and 25dB respectively. (Table 1)&#x0D; DISCUSSION&#x0D; At different anatomic levels, mechanical sound energy is amplified and transmitted to the functional parts of the ear. The tympanic membrane and oval window ratio of 21:1 and malleus-incus lever mechanism ratio of 1.3:1 provide a 28 dB amplification of conductive hearing.1 This gain is reflected by frequency specific air-bone gaps, which can range between 25-40 dB. With the contribution from the external ear, the overall conductive gain is 60 dB.1,3 Damage to the auditory system often results in a loss of hearing sensitivity that is frequency – specific. The presence of a frequency – specific wide air-bone gap suggests ossicular chain discontinuity among patients with chronic otitis media.4 Narrowing of the air-bone gap, which in this case was provided by insertion of the cotton wick, may lead to at least partial restoration of ossicular coupling.&#x0D; The ability of the cotton wick to improve hearing may be attributed to its possession of characteristics for sound conduction and acoustic impedance, such as stiffness, resistance and mass. The effectiveness of the cotton wick was reported to be dependent on its positioning in the ear; the patient would have to insert the wick down to the level of the promontory or oval window, occasionally blow his nose, or reposition the cotton wick to achieve an acceptable hearing level. However, for a patient with completely deaf contralateral ear, a 32.5 dB gain in hearing is very pronounced and significant. &#x0D; The hearing gain produced by the cotton wick only amplified the air conductive component of hearing but not bone conduction. While it afforded amplification of sound and a route of medicine administration, it may also have contributed to sensorineural hearing loss brought about by ototoxicity of medications and thickening of the oval and round window from chronic irritation. For this reason, utmost caution must be advised before considering use of a “cotton wick” to amplify hearing in this manner-- a practice we do not endorse.&#x0D; The cotton wick may have served as a vibrating piston on top of the oval window which amplified hearing. Such a mechanism may conceivably prognosticate potential gain from a contemplated tympanoplasty in the same way that the “paper patch test”5 predicts simple myringoplasty outcomes. Having said that, the diagnostic utility of such a cotton wick requires further investigation before potential clinical applications such as prognostication of tympanoplasty are theorized. Could future studies show that a preoperative cotton wick (or equivalent device) may approximate potential gains from a good tympanoplasty with ossiculoplasty in a patient with total tympanic perforation and ossicular chain loss?&#x0D; &#x0D; Sincerely,&#x0D; Ryner Jose D. Carrillo, MD, MSc&#x0D; Precious Eunice R. Grullo, MD, MPH&#x0D; Maria Luz M. San Agustin, RN, MClinAudio&#x0D; &#x0D;

Oval window atresia (OWA) is a rare otologic condition often associated with a maximal conductive hearing loss, and variable ossicular and facial nerve canal (FNC) anomalies, which have contributed to suboptimal middle ear surgical outcomes. No grading scheme exists to detail the spectrum of associated temporal bone anomalies in OWA; therefore, our objectives were to complete an audiometric and radiographic review to characterize audiometric patterns of hearing loss, and refine the classification system for OWA to determine suitability for middle ear surgery. A retrospective audiometric and radiographic review was conducted at a pediatric tertiary care institution. Patients with OWA identified on temporal bone computerized tomography (CT) scans obtained from 01/2010 to 06/2024 were included. Audiological, radiological, and patient factors were analyzed. Thirty-one patients (48 ears) with OWA were identified. Across frequencies, the air-bone gap decreased significantly as frequency increased (ANOVA with pairwise comparisons, p < 0.001) due to a worsening of bone conduction thresholds and improvement in air conduction thresholds. The FNC was abnormal in 43/48 ears and was determined to overlay the oval window in 6 ears. Additional anomalies included inferiorly displaced, dehiscent, and duplicated canals. Ossicular anomalies were reported in 46/48 ears, and stapedial anomalies were most common. Our findings indicate OWA may manifest audiometrically with consistent and specific hearing loss characterized by a 60-80 dB ABG at lower frequencies that decreases above 2 kHz. CT findings of OWA show considerable variability. We propose a new classification system for OWA based on facial nerve position as this directly influences middle ear surgical feasibility.

Computed tomography is the technique of choice to study the malformations of the auricle, external auditory canal (EAC) and middle ear. The best image quality with the lowest radiation dose can be achieved when high-end Cone Beam CT scanners are used. The 125 μm spatial resolution images they provide are crucial in the detection of subtle ossicular and oval/round window malformations. Knowledge of the embryology helps to understand which malformations can be found and atresia and stenosis of the EAC are the most frequently found malformations of the outer ear. First Branchial Cleft Anomalies are rare and are best studied using MR. Middle ear malformations can develop in association with or in the absence of EAC deformities. Anomalies of the ossicles, facial nerve, oval window, round window, etc., can all be studied in detail with CT. However, MR is needed for the detection of congenital middle ear cholesteatomas and for cholesteatomas which are caused by congenital middle ear malformations and their resulting bad middle ear aeration. Inner ear malformations normally are not associated with middle and outer ear anomalies and high-resolution MR is the best adapted technique to detect vestibular, cochlear and cochleovestibular nerve malformations. New classifications of the labyrinthine malformations and VIIIth nerve malformations are used and their goal is to warn the surgeon for potential hazards during surgery and especially when cochlear implantation is considered. Finally the outer, middle and inner ear can be involved together in syndromes and therefore both MR and CT are often required in these patients. In this chapter the embryology and most frequent malformations of the outer, middle and inner ear will be discussed as well as the contemporary imaging techniques that should be used.KeywordsSemicircular CanalExternal Auditory CanalCochlear ImplantationBranchial ArchInternal Auditory CanalThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.