Audiologic Outcomes After Vestibulotomy in Patients With Congenital Absence of the Oval Window.

OBJECTIVE: To examine the clinical features and surgical outcomes in patients with congenital absence of the oval window (CAOW), and to investigate the potential factors that affect audiologic results. STUDY DESIGN: A retrospective chart review. SETTING: A tertiary academic center. PATIENTS AND INTERVENTION: A total of 17 ears among 16 patients were confirmed to have CAOW. Among them, 13 ears underwent vestibulotomy for hearing reconstruction. Clinical parameters associated with the hearing outcomes were analyzed. MAIN OUTCOME MEASURES: A mean air-bone gap (ABG) after 6-month and long-term follow-up was compared with preoperative measurements. RESULTS: Intraoperative findings showed that anomalies of the malleus or incus were observed in 11 ears (64.7%), stapes anomalies were present in all ears (100%), and facial nerve anomalies were present in 10 ears (58.8%). Because of unfavorable facial nerve anomalies, hearing reconstruction was aborted in four cases (23.5%). In the hearing reconstruction group, the mean ABG at 6 months postoperation was significantly reduced after compared with the preoperative value (44.0 ± 8.4 dB versus 58.8 ± 9.1 dB, p = 0.006). After dividing ears into a success subgroup (ABG ≤ 30 dB, seven ears) and non-success subgroup (ABG > 30 dB, six ears), the use of a drill during vestibulotomy was significantly related to a poor hearing outcome (100% versus 16.7%, p = 0.015). The long-term follow-up result (mean, 60 mo) revealed no deterioration compared with the 6-month postoperative result. Five ears (29.4%) underwent revision surgery, and three of them showed ABG improvements. No serious complications were reported. CONCLUSION: Vestibulotomy is an effective and safe option for hearing restoration in patients with CAOW, particularly when the use of a drill is not required. The long-term audiologic outcome is also reliable.

Bone-conduction hearing aid is effective in congenital oval window atresia.

BACKGROUND: Implantable bone-conduction hearing aids (BCHA) are effective in patients with congenital ear malformations.However, there is no large sample study to verify the efficacy of Bonebridge in patients with congenital oval window atresia. OBJECTIVES: To investigate efficiency of implantable bone-conduction hearing aids in Mandarin-speaking patients with congenital oval window atresia. MATERIAL AND METHODS: We retrospectively analyzed 15 patients, who were confirmed with either unilateral or bilateral congenital oval window atresia by temporal bone CT. All patients were implanted with a bone-conduction hearing device between July 2016 and July 2019 at Beijing Tongren Hospital, Capital Medical University. Pure tone audiometry (PTA), air-bone gap (ABG), speech discrimination scores (SDSs), and hearing thresholds were performed. RESULTS: Postoperative complications including facial paralysis were particularly rare. Unaided mean sound field threshold was 62.2 ± 10.5 dBHL and that with implantable bone-conduction hearing aids was 39.1 ± 13.2 dBHL (p < 0.01). The mean speech discrimination scores improved greatly (p < 0.01), specifically with regard to sentence and disyllabic words. CONCLUSIONS: Patients with congenital oval window atresia often show moderate to severe conductive hearing loss. Implantable bone-conduction hearing aids are considerably safe and stable for hearing rehabilitation. It is a novel treatment modality for Mandarin-speaking patients with congenital oval window atresia.

Oval window perilymph fistula in child with recurrent meningitis and unilateral hearing loss.

A 2-year-old boy presented to Ears, Nose and Throat (ENT) surgeons with unilateral hearing loss. Following a prodrome of upper respiratory tract infection (URTI), he developed two episodes of pneumococcal meningitis in quick succession. This case demonstrates an unusual cause of perilymph fistula diagnosed on imaging and confirmed surgically. He had failed the Newborn Hearing Screening Programme and was therefore referred to audiology, who confirmed profound sensorineural hearing loss in the right ear. MRI showed incomplete partitioning (type 1) of the right cochlea, suggesting cerebrospinal fluid (CSF) leak from the region of the stapes. Exploratory tympanotomy confirmed this, and proceeded to CSF leak repair, obliteration of the Eustachian tube, subtotal petrosectomy, abdominal fat grafting and blind sac closure. Although middle ear effusions are common; particularly in children with recent URTI, the possibility of otogenic CSF leak needs to be considered, especially in cases of recurrent meningitis.

Isolated Congenital Middle Ear Malformations: Comparison of Preoperative High-Resolution CT and Surgical Findings.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

CT Imaging Categorization and Biomarker Study of Anomalous Tympanic Segment of the Facial Nerves in Patients With Hearing Loss in the Absence of Microtia.

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.

Surgical Management for Dysplastic or Congenitally Absent Oval Window.

OBJECTIVE: To evaluate surgical findings and hearing results for patient's undergoing the described surgical approach for congenitally absent or dysplastic oval window (OW). STUDY DESIGN: The Institutional Review Board approved retrospective review of patients with conductive hearing loss (CHL) operated on from 1992 to 2016. SETTING: Academic tertiary center. PATIENTS: Patients with CHL, an intact tympanic membrane (TM), and without history of chronic infection underwent middle ear exploration. Eleven patients and 13 ears underwent an oval window drill-out (OWD) procedure. INTERVENTION: Eleven patients presented, all with dysplastic or congenitally absent oval window (CAOW). CHL was identified using audiometry and tuning forks, many patients also had preoperative computed tomography temporal bones. A transcanal approach was used and an OWD was performed with a variety of prostheses placed. MAIN OUTCOME MEASURE: Audiometric studies before and after intervention were compared with 12 month and long-term follow-up (1-22 yr). RESULTS: Preoperative air-bone gaps ranged from 40 to 60 dB and averaged 55.1 dB. Postoperative air-bone gaps ranged from 0 to 60 dB and averaged 24.1 dB. The preoperative pure-tone average (PTA) ranged from 55 to 99 dB and averaged 71.3 dB. Postoperative PTA ranged from 21 to 108 dB and averaged 49.6 dB. CONCLUSION: Dysplastic and CAOW are uncommon congenital major ear anomalies. OWD is a viable treatment option, though careful counseling is critical, as significant complications are possible, especially with facial nerve (FN) abnormalities. This series demonstrates successful closure of the air-bone gap for many patients with this technique.

[Vibrant soundbridge implantation of congenital atresia of oval window(with summary of nine cases].

Objective:To investigate the surgical effects of round window implantation of vibrant soundbridge(VSB)for patients with congenital oval window atresia.Method:Retrospectively analyze the clinical information of 9 cases of congenital oval window atresia as well as the pre-and post-operative hearing and speech results. Three of them had undergone or attempted the vestibulotomy but obtained poor results. All cases underwent round window implantation of VSB. Result:All patients obtained an improvement of 21-33 dBHL after implantation. In the speech recognition rate test, the average increase of disyllabic words was 62%, and 60% in the sentence test. During the follow-up of 51 months in average, 2 cases had a decline of auditory benefit and finally 1 case regained the improvement after reoperation. Conclusion:Round window implantation can get a fairly good result in congenital oval windows atresia cases.

Congenital oval or round window malformations in children: Surgical findings and results in 17 cases.

OBJECTIVES/HYPOTHESIS: To prospectively evaluate surgical findings and hearing results in children undergoing surgery for congenital oval or round window malformations (class IV malformations). STUDY DESIGN: A nonrandomized, nonblinded, case series of prospectively collected data. METHODS: Fourteen consecutive pediatric patients who underwent 17 surgical procedures for congenital oval or round window malformations in a tertiary referral center were included. Postoperative pure-tone audiometry was available in 15 cases. The surgical technique for repair of the ossicular chain was dictated by the surgical findings at the time of surgery. The majority of the cases underwent ossiculoplasty using a Teflon piston, bucket-handle prosthesis, or total ossicular replacement prosthesis. Associated surgical techniques included malleus relocation and oval window drill-out procedure. The main outcome measures were preoperative and postoperative hearing status using four-frequency (0.5, 1, 2, and 4 kHz) audiometry. Air-conduction thresholds, bone-conduction thresholds, and air-bone gap were measured. Postoperative audiometry was performed at 3, 6, 9, 12, 18, and 24 months after surgery and at a yearly interval thereafter. RESULTS: Postoperative air-bone gap closure to 10 dB or less was achieved in 47%. A postoperative air-bone gap closure to within 20 dB or less was achieved in 60%. Postoperative sensorineural hearing loss did not occur in this series. CONCLUSIONS: Middle ear surgery for class IV abnormalities is feasible, but success percentages are much lower compared to other types of congenital ossicular malformations. Surgeons should be particularly careful in case of facial nerve abnormalities on computed tomography or during middle ear exploration. LEVEL OF EVIDENCE: 4 Laryngoscope, 126:2552-2558, 2016.

Round window application of an active middle ear implant (AMEI) system in congenital oval window atresia.

CONCLUSION: Application of the Vibrant Soundbridge to the round window (RW) membrane can be utilized as an efficient therapy for congenital oval window (OW) atresia. OBJECTIVE: To report the surgical technique and auditory outcome of an active middle ear implant (AMEI) system used in patients with congenital OW atresia. METHODS: Nine subjects with congenital OW atresia (six males and three females, ranging in age from 5.5 to 25 years, average 12.5 years) were implanted with an AMEI (Vibrant Soundbridge) at the round window (RW-Vibroplasty). Five cases were diagnosed as having isolated congenital OW atresia while four patients presented with combined external/middle ear malformation. RESULTS: An improvement of 30 dB in average pure-tone air conduction thresholds (0.5-4 kHz) was achieved, with the high frequencies showing greater results. The subjects achieved postoperative speech recognition scores of 80-100% on the Computerized Mandarin Speech Test System (CMSTS) sentence test. Bone conduction thresholds were confirmed as stable in all subjects postoperatively. Decline in auditory benefit was noticed in two subjects, who then underwent revision surgery. One of these revision surgery patients then experienced stable hearing recovery, while the other patient's hearing declined.

Congenital malformation of the oval window: experience of radiologic diagnosis and surgical technique.

The aim of this study was to introduce and discuss the method of preoperative radiological diagnosis to the congenital absence or atresia of the oval window (OW), and the method of surgical treatment. From July 2010 through August 2014, patients with normal external canal and tympanic membrane but conductive hearing loss underwent high resolution CT scan (HRCT). The multi-planar reformation (MPR), a post-processing protocol, was used. The patients with diagnosis of OW atresia and malformed stapes preoperatively underwent surgical treatment. The vestibular drilled-out and promontory drilled-out technique was used to reconstruct the ossicular chain. In the preoperative radiological diagnosis, six patients (ears) were noted to have congenital absence or atresia of the oval window with malformed facial nerve (class 4) and two patients (ears) were found to have footplate fixation (class 2). In the surgical treatment of eight ears, the malformed structure was identified and the ossicular chain reconstruction was made in six ears. The coronal HRCT CT imaging and the MPR post-processing technique can provide us practical and definite information for surgical treatment, especially in the discrimination of OW atresia and the fixed stapedal footplate. The promontory drill-out technique, fenestration in the bottom of the basal turn, provides us a new method in the hearing reconstruction when the area of OW was fully covered by malformed facial nerve. This technique was first reported in the literature.

Bonebridge Implantation for Conductive Hearing Loss in a Patient with Oval Window Atresia.

The occurrence of oval window atresia is a rare anomaly with conductive hearing loss. Traditional atresia surgeries involve challenging surgical techniques with risks of irreversible inner ear damage. Recent reports on Bonebridge (Medel, Innsbruck, Austria), a novel implantable bone conduction hearing aid system, assert that the device is safe and effective for conductive hearing loss. We present a case of Bonebridge implantation in an eight-year-old girl with bilateral oval window atresia.

[About the surgical treatment of vestibular window abnormalities].

The objective of the present study was to develop the sparing strategy for the surgical treatment of the patients presenting with malformations of the vestibular window based on the results of the evaluation of synopty of the main clues of the internal and middle ears. This article contains the analysis of the effectiveness of the surgical treatment of 17 patients with malformations of the vestibular window operated during the period from 2008 till 2013. It presents the results of investigations into the topographic relationships between the principal structures of the internal and middle ears of special importance for the assessment of the possibilities for the surgical treatment of such patients with the minimal risk of development of postoperative complications. The results of the surgical treatment were estimated based on the data of audiological studies in the early and late postoperative periods. It was shown that none of the patients developed the symptoms of dizziness, unstable gait or sensorineural impairment of hearing in the immediate postoperative period. Good functional results in the form of the reduced bone-air interval (15.2±1.0 dB) were achieved in 13 patients. Nevertheless, the considerable decrease in the sound conductivity in the late postoperative period observed in 64.7% of the patients related to the closure of the vestibular fistula dictates the necessity of developing the novel techniques for its prevention.

Vestibulotomy with ossiculoplasty versus round window vibroplasty procedure in children with oval window aplasia.

OBJECTIVE: To review the surgical procedures and outcomes in children with bilateral oval window aplasia (OWA). STUDY DESIGN: Retrospective cohort review. SETTING: Tertiary referral center. PATIENTS: Children suffering from OWA between 1990 and 2010. INTERVENTION: Vestibulotomy with ossiculoplasty (V-OPL) or round window vibroplasty (RWV). MAIN OUTCOME MEASURES: Findings at radiology and surgery, preoperative and postoperative bone conduction (BC), air conduction (AC), and RWV-air conduction (RWV-AC) thresholds and speech discrimination scores (SDSs). RESULTS: Among 23 children, 11 underwent V-OPL and 8 RWV. Four children in the V-OPL group had aborted surgery and were excluded from the study. In all the remaining 19 children, the 6-month follow-up time showed postoperative AC and SDS values significantly better than the preoperative thresholds in both groups. At the 36-month long-term follow-up, AC and SDS were stable in the RWV group but showed a significant worsening in the V-OPL children compared with the 6-month follow-up results. Preoperative versus postoperative BC values showed a significant difference between the 2 groups at 36 months; 5 of the V-OPL group underwent revision following the same surgical principles, which did not result in improved outcome. CONCLUSION: In children with OWA, V-OPL provides modest long-term results and carries higher risks of BC degradation compared to RWV. Both procedures are technically challenging but considering the respective hearing results and morbidity of primary and revision surgery, we have abandoned the V-OPL procedure in favor of RWV. In infants and children younger than 5 years with OWA previously not considered candidates for hearing restoration, we consider RWV as the first-choice surgery. It has shown to provide significantly better hearing outcomes than traditional atresia surgery with minimal complication rate.

Oval window atresia: a novel surgical approach and pathognomonic radiological finding.

OBJECTIVES: The facial nerve usually occupies the oval window area in patients with oval window atresia. During exploration, if the facial nerve is discovered to lie in the oval window area, this is usually regarded as a contraindication for further surgical intervention. The aim of the present paper is to demonstrate the preoperative pathognomonic radiological sign and describe a new surgical approach for this difficult situation. METHODS: 3 patients and 4 ears were operated due to conductive hearing loss by the same surgeon in a tertiary referral center. Their clinical presentation, radiological findings, surgical findings and final outcomes were evaluated and correlated. RESULTS: Surgical findings were identical in all 4 ears: facial nerve was running over the oval window and tympanic portion was completely dehiscent. Incus long arm was medially displaced due to abnormal development of the stapes suprastructure. In each ear a successful vestibulotomy and teflon piston placement was achieved. Preoperative mean air-bone gap of 47.5dB was improved to 21.5dB. There were no complications. CONCLUSION: Oval window atresia is a rare middle ear anomaly usually regarded as a contraindication for surgical intervention. In this study we present a novel surgical approach with succesful results. However the best approach is to inform the family by showing the nerve on tomography, showing the operation video, informing the family about the sensorineural hearing loss and letting the family choose the treatment option.

The location of the mastoid portion of the facial nerve in patients with congenital aural atresia.

In order to investigate the location of the mastoid portion of the facial nerve in patients with congenital aural atresia and to assess its effect on the round window middle ear implant (MEI) transducer implantation approach, 70 patients with unilateral congenital aural atresia were examined by computer tomography (CT). The patients were divided into two groups based on their ages: 44 patients in Group A (2-12 years) and 26 patients in Group B (13-29 years). CT scans were reviewed for each patient. Based on the CT findings, the mastoid portion of the facial nerve's spatial configuration with respect to the oval and round windows was qualitatively recorded. Additionally, the exact location of the facial nerve was measured quantitatively. The results suggested that of the 70 deformed ears, 57 had facial nerves located at the round window, six at the oval window, and seven at the normal site. Of the 70 normal opposite ears, 63 had facial nerves located at the normal site, and the other seven had facial nerves located at the round window. Based on the quantitative measurements, the mastoid portion of the facial nerve was more anteriorly positioned in the deformed ears: 3.44-6.09 mm more anteriorly located in Group A and 4.35-7.41 mm more anteriorly located in Group B. In conclusion, in patients with congenital aural atresia, the dislocation of the facial nerve could have significant effects on the surgical approach to round window MEI transducer implantation.

Cochlear implantation in children with "CHARGE syndrome": surgical options and outcomes.

CHARGE syndrome is a rare, polymalformative disease, representing one of the major causes of associated blindness and deafness. Bilateral, severe-profound, sensorineural hearing loss is common in CHARGE children. Aim of this study is to present our results in children with "CHARGE syndrome" submitted to cochlear implantation (CI). The frequency of anatomic anomalies, possible variations in the surgical technique of CI, and the audiological/rehabilitative benefits attained in our patients are reported. we submitted 5 children affected by CHARGE syndrome with profound, bilateral, sensorineural hearing loss to CI. Otoacoustic emissions, auditory brainstem response, acoustic impedance testing, cranial computed tomography and magnetic resonance were carried out preoperatively in all children. CI was performed using the mastoidotomy-posterior tympanotomy approach in two cases, and the suprameatal approach in three children. Infant toddler-meaningful auditory integration scale was used to evaluate kid's audiological performance before and after CI. Intra-operatory findings and postsurgical complications were evaluated. Among our patients, intraoperative anatomical malformations were cochlear hypoplasia (100 %), ossicles malformations (100 %), semicircular canals aplasia (100 %), oval window atresia (60 %), round window atresia (40 %), widening of the aqueduct of the vestibule (20 %), and aberrant course of the facial nerve (20 %). No intra- or postoperative complication was recorded in relation to implant positioning. After a follow-up ranging from 1 to 4.5 years, only 2/5 patients used oral language as the sole mean of communication, 1 started utilizing oral language as the main mean of communication, while 2 patients did not develop any linguistic ability. In conclusion, CI in patients with CHARGE association is feasible and, despite results variability, it should be carried out in CHARGE children with severe hearing loss as soon as possible. Although the selection of a specific surgical technique does not seem to influence the audiological outcome, the suprameatal access is valuable when important surgical landmarks (i.e. lateral semicircular canal and incus) are absent.

Oval window niche height: quantitative evaluation with CT before stapes surgery for otosclerosis.

BACKGROUND AND PURPOSE: Stapes surgery for otosclerosis can be challenging when the oval window niche is narrow. We analyzed the reliability of CT to evaluate the height of the OWN and propose a quantitative criterion to distinguish normal and narrow OWNs. MATERIALS AND METHODS: Fifty-six patients were scheduled for primary stapes surgery and, with available preoperative CT scans, were prospectively enrolled in the study at a tertiary care hospital. OWN height was measured on coronal CT and qualitatively evaluated during surgery. CT findings and surgical observations were matched to determine the preoperative imaging criterion of a narrow OWN. RESULTS: OWN was found to be narrow during surgery in 8 of 56 patients (14%). On CT, mean OWN height measurement was 1.1 mm for the narrow group and 1.8 mm for the normal OWN surgical cases. The cutoff between normal and narrow OWN was computed at 1.3 mm by using discriminant analysis and at 1.4 mm with boxplot analysis. These CT cutoff values allowed a correct classification of "normal" and "narrow" OWN, compared with visual evaluation during surgery. CONCLUSIONS: Measurements of the OWN height provide an accurate and relevant evaluation of this region before otosclerosis surgery. A width below 1.4 mm should be considered at risk for technical difficulties during the stapes footplate approach.

Congenital oval or round window anomaly with or without abnormal facial nerve course: surgical results for 15 ears.

OBJECTIVES: To describe the audiometric results in a consecutive series of patients with congenital ossicular aplasia (Class 4a) or dysplasia of the oval and/or round window (Class 4b), which might include a possible anomalous course of the facial nerve. STUDY DESIGN: Retrospective chart study. SETTING: Tertiary referral center. PATIENTS: A tertiary referral center study with a total of 14 patients with congenital minor ear anomalies as part of a consecutive series (n = 89) who underwent exploratory tympanotomies (15 ears). MAIN OUTCOME MEASURES: Audiometric results. RESULTS: In 8 of 15 ears, ossicular reconstruction was attempted. In the short term (1 mo), there was a serviceable hearing outcome (air-bone gap closure to within 25 dB) in 4 ears. However, the long-term results showed deterioration because of an increased air-bone gap in all but 1 ear. No facial nerve lesion was observed postoperatively. CONCLUSION: Congenital dysplasia or aplasia of the oval and/or round window is an uncommon congenital minor ear anomaly. Classical microsurgical opportunities are rare in this group of anomalies. Newer options for hearing rehabilitation, such as the osseointegrated passive bone conduction devices, have become viable alternatives for conventional air conduction hearing devices. In the near future, upcoming active bone conduction devices might become the most preferred surgical option. In cases in which the facial nerve is only partially overlying the oval window, a type of malleostapedotomy procedure might result in a serviceable postoperative hearing level.

Labyrinthotomy or vestibulotomy in anatomic and congenital variations of the oval window and facial nerve.

OBJECTIVE: To present the results of our experience with labyrinthotomy or vestibulotomy in cases where the oval window is blocked by the facial nerve and in the presence of bilateral congenital agenesis of the oval window, respectively. STUDY DESIGN: Retrospective analysis of the records of the patients operated in two different centers. METHODS: Between 2007 and 2012, 5 ears of 4 patients who were operated on in two different clinics with a presumptive diagnosis of otosclerosis were included in the study. There were 3 female patients and 1 male. The ages ranged from 10 to 26 (mean 19 years). All patients had unilateral conductive hearing loss except 1 (10-year-old girl or patient 1). Pure tone averages were calculated at the frequencies 0.5, 1, 2 and 4 kHz both pre- and postoperatively according to the Committee on Hearing and Equilibrium 1995 Guidelines for the Evaluation of Results of Treatment of Conductive Hearing Loss. All patients underwent a middle ear exploration and postoperatively the initial audiological examination was performed after 6 months. RESULTS: Retrospective analysis revealed that vestibulotomy or labyrinthotomy was performed in 5 ears of 4 patients. Postoperative dizziness was encountered in 2 patients who had vestibulotomy due to oval window agenesis, which ceased spontaneously at 1 month postoperatively. The perioperative period was otherwise uneventful. None of the patients had sensorineural hearing loss or deterioration of hearing. There was a significant improvement in hearing after the operation. A 28-dB improvement in the mean air conduction pure tone thresholds was achieved. CONCLUSION: Vestibulotomy and labyrinthotomy are safe and effective procedures in terms of hearing restoration, which can be applied in cases of congenital agenesis of the oval window or obstruction of the oval window by the facial nerve.

Surgical treatment for congenital absence of the oval window with facial nerve anomalies.

Three patients with a middle ear malformation characterized by the absence of the oval window and complicated by facial nerve anomalies were treated by surgery. Hearing ability of all the patients was improved. A variety of facial nerve anomalies were observed. Fenestration of the vestibule above the facial nerve was performed in the case of 2 of the 3 patients. In the other patient, fenestration of the scala vestibuli below the facial nerve was performed. In the case of all the 3 patients, hearing ability improved after the surgery and remained stable for a long time. Surgery for this disease has been considered difficult because of a high risk of complications. Because all the 3 patients showed excellent long-term surgical results, we suggest that fenestration of the inner ear should be considered one of the main options for the management and treatment of an absent oval window associated with facial nerve anomalies.