Surgical decision-making in superior canal dehiscence syndrome with concomitant otosclerosis.

OBJECTIVE: The diagnosis and management of Superior Canal Dehiscence Syndrome (SCDS) with concomitant otosclerosis can be a challenge. Otosclerosis can mask SCDS symptoms and stapes surgery may reveal or exacerbate vestibular symptoms. Our aim is to present four cases of SCDS with concomitant otosclerosis and thereby informing the reader about the possibility of this dual occurrence and its implications for treatment. CASES: Four patients with SCDS and concomitant otosclerosis are presented. Two patients underwent surgical treatment for both SCDS and otosclerosis and two patients opted for conservative management. OUTCOMES: The main differences between surgically and non-surgically treated cases are the presence of autophony and pressure-induced vertigo and a more severe experience of symptoms in surgically treated cases. Surgically treated cases achieved a sizeable reduction in postoperative air-bone gap and resolution of vestibular symptoms. CONCLUSION: The subjective severity of symptoms in combination with shared decision-making is key in determining the appropriate treatment plan for SCDS and concomitant otosclerosis.

Cochlear Otosclerosis and Secondary Hydrops (Ménière's Syndrome).

ABSTRACT: This article discusses a case of cochlear otosclerosis leading to secondary hydrops and near-complete hearing loss. Histopathological examination revealed advanced multifocal otosclerosis in both temporal bones, with specific focus on cochlear invasion and significant bone resorption. The severity of the case ruled out surgical intervention due to the risk of further hearing loss. The article emphasizes the challenges in managing otosclerosis-related hydrops and highlights the potential use of advanced imaging techniques for diagnosis. The study underscores the complexity of otosclerosis-induced hearing loss, contributing to the understanding of this pathology and its impact on auditory function.

An Endoscopic Procedure for the Simultaneous Treatment of both Otosclerosis and Malleus Fixation.

To report the case of the simultaneous treatment of otosclerosis and malleus fixation through an entirely endoscopic transcanal approach. A targeted transcanalar epitympanotomy with annular bony ridge conservation was planned preoperatively, with 3D CT localization of the fixed part of the malleus head. The upper part of the malleus head and the superior ossified ligament of the malleus were drilled. A 0.6 mm stapedotomy was performed and a piston inserted. The patient's recovery was uneventful, with closure of the air-bone gap on her postoperative audiogram, associated with an overclosure in 500Hz, 1kHz, 2 kHz and 4 kHz. Laryngoscope, 134:2411-2414, 2024.

Endoscopic Findings on Facial Nerve Anatomy During Exclusive Endoscopic Stapedotomy: Clinical Considerations and Impact on Surgical Results.

BACKGROUND: Variations along the facial nerve (FN) course present considerable challenges in the surgical treatment of otosclerosis, often complicating the procedure. Existing knowledge of its tympanic tract and its implications primarily comes from microscopical procedures. This study aims to assess endoscopic findings of FN anatomy in a healthy tympanic cavity and its impact on the stapedotomy procedure, focusing on the risk of complications and functional hearing outcomes. METHODS: A retrospective study on exclusive endoscopic stapedotoplasties between October 2014 and October 2021 at our Otorhinolaryngology University Department was carried out. An evaluation of intraoperative endoscopic findings reviewed in surgical descriptive and/or video records was conducted to assess their potential negative impact on the surgery. Demographic data, preoperative and postoperative hearing thresholds, as well as intraoperative and postoperative complications were analyzed. RESULTS: One hundred fifty-seven subjects were included. A FN partially overhanging the oval window was observed in 7.3% (n=12): 10 prolapsing with bony canal dehiscence and 2 without any detected dehiscence. Each procedure was successfully completed without any issues related to the anomalous anatomy, and in no case, switching to the microscope for the handling of the prosthesis near the dehiscent nerve was required. No facial paralysis occurred, with an early- or long-term postoperative House-Brackman grade of 1 (n=157, 100%). Only 3/157 patients (1.9%) showed a sensorineural threshold reduction of ≥20 dB HL, but a significant air-bone gap improvement was observed (mean closure of 18.36 dB HL, P -lt; .0001). CONCLUSION: The endoscope promotes a concrete description of tympanic FN anatomy, and endoscopic stapes surgery appears to be a safe and viable option when dehiscent or prolapsed FNs reduce the footplate's exposure.

Vertigo Associated with Otosclerosis and Stapes Surgery-A Narrative Review.

Otosclerosis is a pathological condition affecting the temporal bone, and is characterized by remodelling of the labyrinthine bone tissue through a dynamic process of osteolysis and osteogenesis. This condition progressively leads to hearing loss, tinnitus, and vertigo. Stapedotomy, a surgical procedure involving the removal of the stapes superstructure and its replacement with a prosthesis, is the treatment of choice to improve hearing in individuals with otosclerosis. However, vestibular dysfunction is a significant complication associated with this procedure, which can occur intraoperatively or postoperatively, ranging from the immediate postoperative period to weeks, months, or even years after surgery. This paper aims to provide a comprehensive review of the most important causes of vertigo associated with otosclerosis and stapes surgery with the goal of minimizing the incidence of this complication. Understanding the underlying factors contributing to vertigo in this context is crucial for the prevention and effective management of vertigo in patients undergoing stapedotomy.

Otosclerosis under the magnifying glass.

Otosclerosis is a bone condition affecting the stapes bone within the otic capsule, and its exact cause is still unknown. It is characterized by a lack of proper remodeling of newly formed vascular and woven bone, leading to the development of abnormal osteons and the formation of sclerotic bone. Bilateral otosclerosis is seen in 80% of patients and 60% of otosclerosis patients have a family history of the condition. The etiology of this disease is still unknown, there are lots of theories to explain it. The histopathological (HP) studies of otosclerosis showed that osteoblasts, osteoclasts, vascular proliferation, fibroblasts, and histiocytes were observed in the stapes footplate. The onset of the symptoms occurs by the early third decade of life, usually it doesn't start later. In otosclerosis, the energy exerted by sound at the level of the tympanic membrane is reduced in the inner ear due to the fixation and rigidity of the ossicular chain, leading to hearing loss, especially for low frequencies. The primary clinical symptom of otosclerosis is conductive hearing loss but it is important to note that sensorineural hearing loss and mixed hearing loss can also occur as secondary symptoms of the condition. Another symptom present in patients with otosclerosis is tinnitus. The paper carried out a retrospective study of 70 patients diagnosed with otosclerosis in the Department of Otorhinolaryngology of Emergency City Hospital, Timisoara, Romania, between January 2021 to December 2022. Tissue fragments were processed at Service of Pathology by standard Hematoxylin-Eosin staining. The HP diagnosis was completed using Masson's trichrome staining, Giemsa histochemical staining, and immunohistochemical (IHC) reactions with anti-cluster of differentiation (CD)20, anti-CD3, anti-CD4, anti-CD8, anti-CD34, and anti-CD31 antibodies. The microscopic examination showed a chronic diffuse inflammatory infiltrate that consisted predominantly of mature T-lymphocytes, immunohistochemically positive for CD3, CD4 and CD8. There were also present rare CD20-positive B-lymphocytes. Among the lymphocytes, relatively numerous mast cells were identified, highlighted histochemically by the Giemsa staining. They had numerous purple-violet intracytoplasmic granules. In the connective tissue support, a relatively rich vascular network was identified, consisting of hyperemic capillaries, highlighted immunohistochemically with anti-CD31 and anti-CD34 antibodies. Bone tissues trabeculae showed extensive areas of fibrosis. The collagen fibers were highlighted by Masson's trichrome staining, being stained in green, blue, or bluish green.

The Impact of Surgical Expertise on the Cost-Effectiveness of Stapes Surgery.

INTRODUCTION: Otosclerosis is the primary cause of conductive hearing loss with normal otoscopy. As the condition worsens, certain patients may develop a sensorineural component. Patients with successful surgeries may still need hearing aids, which creates a dilemma for health professionals as there are insufficient data to make informed decisions. This study investigated the influence of the surgeon's proficiency level, individual patient factors (e.g., age at the time of intervention and survival rates), and surgery costs on the cost-effectiveness of stapes surgery. METHODS: We performed a cost-effectiveness analysis using an adapted Markov model incorporating annual all-cause mortalities. In addition, we introduced sensitivity analyses to address the effects of surgical expertise on adults with bilateral conductive hearing loss due to otosclerosis. A model was developed based on a decision tree with treatment options and complication scenarios for otosclerosis patients undergoing stapes surgery or receiving hearing aids. Annual all-cause mortality was considered. A sensitivity analysis was performed assigned to different training levels ("experts" and "less experienced") to simulate the effects of surgical experience on the cost-effectiveness of surgical outcomes. Successful surgery was defined as closing of the air-bone gap to 10 dB or less. Based on published data, "experts" were simulated with a 93.7% success rate, and "less experienced" were manufactured with a 68.9% success rate. RESULTS: Stapes surgery provides improved quality of life (QoL) compared to hearing aids with lower cumulative costs up to 87 years of age in the case of "expert" surgeons and up to 78 years of age, when performed by "less experienced" surgeons. CONCLUSIONS: Primary stapes surgery is highly cost-effective and delivers improved QoL compared to hearing aids with lower cumulative costs. Additionally, undergoing stapes surgical training remains highly cost-effective.

Cochlear implantation in advanced otosclerosis: utility of pre-operative radiological assessment in predicting intra-operative difficulty and final electrode position.

OBJECTIVE: This study aimed to determine if pre-operative radiological scoring can reliably predict intra-operative difficulty and final cochlear electrode position in patients with advanced otosclerosis. METHOD: A retrospective cohort study of advanced otosclerosis patients who underwent cochlear implantation (n = 48, 52 ears) was compared with a larger cohort of post-lingually deaf adult patients (n = 1414) with bilateral hearing loss and normal cochlear anatomy. Pre-operative imaging for advanced otosclerosis patients and final electrode position were scored and correlated with intra-operative difficulty and speech outcomes. RESULTS: Advanced otosclerosis patients benefit significantly from cochlear implantation. Mean duration of deafness was longer in the advanced otosclerosis group (19.5 vs 14.3 years; p < 0.05). CONCLUSION: Anatomical changes in advanced otosclerosis can result in increased difficulty of surgery. Evidence of pre-operative cochlear luminal changes was associated with intra-operative difficult insertion and final non-scala tympani position. Nearly all electrodes implanted in the advanced otosclerosis cohort were peri-modiolar. No reports of facial nerve stimulation were observed.

Otosclerosis: audiometric results and quality of life after stapedectomy with interposition or CO2 laser-calibrated stapedotomy without interposition.

BACKGROUND: The surgical treatment of otosclerosis consists of the replacement of the stapes using a piston. AIMS/OBJECTIVES: The objective of this study is to assess the audiometric results and quality of life (QOL) of patients who underwent surgery for otosclerosis by stapedectomy with fascia interposition (STIP) or by stapedotomy using CO2 laser (SLaser) without fascia interposition. MATERIAL AND METHODS: Ninety-one patients operated on for otosclerosis by STIP (40 patients) and by SLaser (51 patients) were included. Audiometric results were graphically displayed using the Amsterdam Hearing Evaluation Plot and were compared to the Common Otology Database (COD) comprising 660 patients. The patients' QOL was assessed with an otological validated survey. The significance level was p < .05. RESULTS: There was no significant difference in hearing improvement between SLaser and STIP-operated patients. There was no significant difference between our results and that of COD. QOL was significantly improved (+3.5/10) postoperatively for both STIP and SLaser in both social and professional fields. CONCLUSIONS AND SIGNIFICANCE: By comparing QOL and hearing gain of STIP and SLaser, our results suggest that both surgical techniques are a safe and successful treatment for otosclerotic stapes fixation. Further studies aiming at comparing larger series may confirm and refine these results.

Audiometric and Self-Reported Outcomes in Patients with Otosclerosis and a Small Air-Bone Gap after Stapes Surgery.

INTRODUCTION: The main determinant in deciding on stapes surgery in patients with otosclerosis is the degree of hearing loss, specifically the size of the preoperative air-bone gap (ABG). The debate over the minimum ABG centers on the risk-to-benefit ratio of stapes surgery in patients with small ABG (sABG). The aim of this study was to measure the audiological outcomes and self-assessed satisfaction in a group of otosclerosis patients with an sABG who underwent stapedotomy. METHODS: There were 83 patients with preoperative sABG ≤25 dB HL (mean of 500, 1,000, 2,000, 4,000 Hz) included in this study. Audiometry was performed before surgery and 6 months and 12-36 months after surgery. Self-reported patient outcomes before and after surgery were collected using questionnaires. RESULTS: At the 6-month follow-up, the ABG was closed within 10 dB in 63 (78.8%) cases. Preoperatively, tinnitus was present in 70% of patients, of which 66% reported that tinnitus was a moderate or severe problem. Postoperatively, 71% of patients experienced a significant reduction in tinnitus severity and 34% of them reported complete disappearance. The self-report outcomes relating to quality of life and hearing reflected a good level of satisfaction in most patients. CONCLUSION: The possibility of reducing bothersome tinnitus after stapes surgery, and thus improving the patient's quality of life, should be taken into account when making a decision on stapes surgery in these patients.

Retrospective Study of 157 Patients with Otosclerosis to Evaluate Association Between Carhart Notch on the Preoperative Bone-Conduction Audiogram and Postoperative Hearing and Balance Evaluated by the Vestibular Disorders Activities of Daily Living Scale.

BACKGROUND A Carhart notch in the pure tone audiogram can be an indicator of stapes fixation in otosclerosis. This retrospective study of 157 patients with otosclerosis aimed to evaluate the association between the presence of a Carhart notch on the preoperative bone-conduction audiogram and postoperative hearing and balance evaluated by the Vestibular Disorders Activities of Daily Living scale. MATERIAL AND METHODS Patients with suspected otosclerosis based on medical history and audiometric tests were considered. The analysis included 157 consecutive patients who underwent surgery in the years 2016 to 2019, in whom the diagnosis of otosclerosis was confirmed during surgery. Carhart notch was defined as an impairment in the bone conduction threshold of ≥7.5 dB for 2000 Hz frequencies above the mean thresholds at higher and lower adjacent frequencies. The Vestibular Disorders Activities of Daily Living subjective scale was used in the preoperative period and 4 and 12 months after surgery. RESULTS The preoperative presence of Carhart notch and progressive sensorineural hearing loss were statistically significantly correlated with more common onset of tinnitus and then dizziness (P=0.006). Preoperative vertigo was observed in patients who had Carhart notch observed in the preoperative audiometric test. This vertigo more commonly coexisted with profound sensorineural hearing loss and minor or no improvement in average values of bone conduction after surgery (P=0.002). CONCLUSIONS Preoperative Carhart notch on audiogram and the severity of sensorineural hearing loss were associated with tinnitus and vertigo. However, preoperative Carhart notch was not associated with persistent postoperative tinnitus in patients with cochlear otosclerosis.

Radiological parameters and audiometric findings in otosclerosis: is there any relationship?

OBJECTIVE: The role of high-resolution computed tomography scans in otosclerosis remains uncertain. There is a debate over the relationship between radiological and audiometric findings among patients. METHOD: Pre-operative audiometry and high-resolution computed tomography findings from 40 ears with surgically confirmed otosclerosis were compared. High-resolution computed tomography scan data regarding the characteristics of the disease foci, the endosteal extension and the occurrence of internal auditory canal diverticula were obtained. The influence of each radiological variable on the simple pure tone average, the high-frequency pure tone average and the bone-conduction pure tone average were investigated. RESULTS: Cases with endosteal extension (p = 0.047) and a higher number of affected sites within the otic capsule had a worse bone-conduction pure tone average, although it was only significant for the latter (p = 0.006). Those without concomitant retrofenestral disease (p = 0.019) had better simple pure tone average. CONCLUSION: The number of sites of involvement and concomitant retrofenestral disease seem to significantly impact audiometric findings in otosclerosis.

Association Between Postoperative Vertigo and Hearing Outcomes After Stapes Surgery for Otosclerosis.

OBJECTIVE: During the postoperative period, most patients with otosclerosis report vertigo and/or nausea caused by interventions within the inner ear. The aim of this study was to evaluate both early and late vertigo associated with hearing improvement after stapes surgery for otosclerosis. METHODS: The analysis included 170 patients admitted to the hospital undergoing their first surgery for otosclerosis. Audiological diagnostics, surgical techniques, and symptoms reported by the patients were all analyzed. RESULTS: A statistical correlation and an unfavorable influence of late, undesired symptoms, such as vertigo, nausea/vomiting, and nystagmus, on final hearing improvement after surgical treatment of otosclerosis were found. Prostheses that were too long or placed too deep within the inner ear space were the most frequent cause of both vertigo and lack of hearing improvement observed after stapedotomy. CONCLUSIONS: A significant negative influence on bone conduction thresholds, particularly at 2000 Hz, was associated with vestibular symptoms persisting for 7 days after the surgery. Symptoms of impaired bony labyrinth function after stapedotomy, persisting for more than 1 year, were associated with insufficient reduction of the air-bone gap and worse improvement in bone conduction thresholds at 1000 and 2000 Hz. The cause of both problems was related to a prosthesis that was too long or placed too deep in the inner ear during stapedotomy.

Cochlear Implantation in Far Advanced Otosclerosis: A Systematic Review and Meta-Analysis.

OBJECTIVE: To evaluate speech outcomes and facial nerve stimulation (FNS) rates in patients with far advanced otosclerosis (FAO) after cochlear implantation. METHODS: A systematic review was performed using standardized methodology of Medline, EMBASE, PubMed, Cochrane, and Web of Science databases. Studies were included if adults with FAO underwent cochlear implantation. Exclusion criteria included concurrent otologic history (e.g., Meniere's disease, superior canal dehiscence), non-English-speaking implant users, case reports, abstracts, and letters/commentaries. Bias was assessed using the Newcastle-Ottawa Scale for cohort studies and the National Institute of Health Scale for case series. The primary outcome measure was speech discrimination and the secondary outcomes were rates of partial insertion and FNS. RESULTS: Twenty-seven studies evaluated cochlear implantation in FAO. Due to the heterogeneity of testing methods, statistical pooling of speech discrimination was not feasible, but qualitative synthesis indicated a positive effect of implantation. Pooled rates of FNS were 18% (95% confidence interval, CI 12%-27%) and the rate of partial insertion was 10% (95% CI 7%-15%). CONCLUSION: Cochlear implantation in FAO demonstrates significant gains in speech discrimination scores with higher rates of FNS and partial insertion. Laryngoscope, 133:1288-1296, 2023.

Are there differences in revision stapes surgery outcomes between university and county clinics? A study from the quality register for otosclerosis surgery in Sweden.

PURPOSE: The aim of the study was to investigate hearing outcomes in stapes revision surgery with regard to the type of clinic (university clinic or county clinic). Furthermore, the aim was to investigate the risk of complications with a focus on tinnitus, hearing deterioration, and taste disturbance 1 year after surgery. METHODS: The study is based on data from the Swedish Quality Register for Otosclerosis Surgery (SQOS). Two study protocols were completed by the surgeon, and a questionnaire was distributed to the patients 1 year after surgery. A total of 156 revisions were available for analysis with both preoperative and postoperative audiometry data. RESULTS: Seventy-five percent of the patients reported better to much better hearing 1 year after revision surgery. An air bone gap ≤ 20 dB postoperatively was seen in 77% of the patients. Four percent had hearing deterioration ≥ 20 dB PTA4 AC. Eleven percent had worsened or newly developed tinnitus, 5% had taste disturbance, and 3% had dizziness 1 year after surgery. Preoperative and postoperative hearing did not differ between patients operated on in university vs. county clinics. CONCLUSIONS: Revision surgery in otosclerosis is a challenge for otologists, but no differences in hearing outcomes between university and county clinics were found in this nationwide study. The risk of hearing deterioration and deafness is higher than in primary stapes surgery, and revision surgery should be recommended primarily in cases with a large air-bone gap and moderate to severe preoperative hearing loss.

Otopathologic and Computed Tomography Correlation of Internal Auditory Canal Diverticula in Otosclerosis.

INTRODUCTION: Internal auditory canal (IAC) diverticula, also known as IAC cavitary lesions or anterior cupping of the IAC, observed in otopathologic specimens and high-resolution computed tomography (CT) scans of the temporal bone are thought to be related to otosclerosis. Herein, we examined the usefulness of CT scans in identifying diverticula and determined whether IAC diverticula are associated with otosclerosis on otopathology. METHODS: One hundred five consecutive specimens were identified from the National Temporal Bone Hearing and Balance Pathology Resource Registry. Inclusion criteria included the availability of histologic slides and postmortem specimen CT scans. Exclusion criteria included cases with severe postmortem changes or lesions causing bony destruction of the IAC. RESULTS: Ninety-seven specimens met criteria for study. Of these, 42% of the specimens were from male patients, and the average age of death was 77 years (SD = 18 yr). IAC diverticula were found in 48 specimens, of which 46% were identified in the CT scans. The mean area of the IAC diverticula was 0.34 mm 2 . The sensitivity and specificity of detecting IAC diverticula based on CT were 77% and 63%, respectively. Overall, 27% of specimens had otosclerosis. Histologic IAC diverticula were more common in specimens with otosclerosis than those without (37.5% versus 16%; p = 0.019). Cases with otosclerosis had a greater mean histologic diverticula area compared with nonotosclerosis cases (0.69 mm 2 versus 0.14 mm 2 ; p = 0.001). CONCLUSION: IAC diverticula are commonly found in otopathologic specimens with varied etiologies, but larger diverticula are more likely to be associated with otosclerosis. The sensitivity and specificity of CT scans to detect IAC diverticula are limited.

Hearing Improvement in the Patients Operated on Otosclerosis by Right-Handed Surgeons.

BACKGROUND: Otosclerosis is a disease of the osseous labyrinth. The disease causes 5% to 9% of all cases of hearing loss and 18% to 22% of conductive hearing loss. The treatment of choice is a surgery. The hearing improvement after the operation is determined by various factors. AIMS/OBJECTIVES: The aim of the analysis is to determinate changes in hearing after stapedoplasty in view of surgery side in the patients operated on otosclerosis by right-handed surgeons. MATERIAL AND METHODS: The analysis involved patients hospitalized and operated on otosclerosis between 2012 and 2018. Only patients with their first middle ear surgery due to otosclerosis were included in the study. The patients were operated by 2 right-handed surgeons who used the same surgical technique and had similar experience in otosclerosis surgery. The study included patients who were divided into 2 groups: with self-tightening prosthesis and with manually tightening prosthesis. RESULTS: The procedure performed by right-handed operators on the left side using prostheses requiring manual fixation on the incus was associated with poorer audiometric results compared to the results of surgeries on the right side. In patients with the self-tightening prostheses, the audiometric improvement of hearing was bilaterally comparable independently from operation side. CONCLUSION: (1) The dependence of hearing improvement on the surgery side was demonstrated in cases of surgeries performed on the left ear by right-handed surgeons, particularly with manually tightening prosthesis. (2) Self-tightening prostheses in stapedotomy limit the human factor, reducing the risk of complications after otosclerosis surgery and provide repeatable hearing improvement.

Comparison of different oval window sealing materials in stapes surgery: systematic review and meta-analysis.

OBJECTIVE: To compare the efficacy and safety characteristics of different materials used for oval window sealing during stapedotomy. METHODS: A systematic review was conducted according to the PRISMA guidelines. Published international English literature from January 1, 2000 to December 2021 was screened, checking for studies that compared different materials utilization in patients undergoing stapedotomy surgery for otosclerosis or congenital stapes fixation. Data related to the efficacy and safety of each material were extracted. The primary outcome measure was the air-bone gap (ABG) closure after surgical intervention. RESULTS: Six studies were included in the metanalysis. Because of the heterogeneity of the treatments adopted, we assessed the use of the fat compared to all other treatments, and the use of the gelfoam compared to all other treatments. In the former analysis (fat vs others) we did not identify differences in ABG closure between the groups (p = 0.74), with a low heterogeneity of the results (I2 = 28.36%; Hedge's g = 0.04, 95% CI - 0.19 0.27); similarly, we did not identify differences between the use of gelfoam and other treatments (p = 0.97), with a low heterogeneity of the results (I2 = 28.91%; Hedge's g = 0.00, 95% CI - 0.20 0.21). CONCLUSIONS: Numerous options are available for oval window sealing during stapedotomy, with acceptable safety and effectiveness profiles. Based on the current data, no definitive recommendation can be made regarding the choice of one material over another, and the convenience of sealing over no sealing at all.

Cochlear Implant Outcomes in Patients With Otosclerosis: A Systematic Review.

OBJECTIVE: This study aimed to establish hearing outcomes after cochlear implantation in patients with otosclerosis. MATERIALS AND METHODS: We conducted a systematic review and narrative synthesis. Databases searched were as follows: MEDLINE, PubMed, Embase, Web of Science, Cochrane Collection, and ClinicalTrials.gov . No limits were placed on language or year of publication. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. RESULTS: Searches identified 474 abstracts and 180 full texts, with 68 studies meeting the inclusion criteria and reporting outcomes in a minimum of 481 patients with at least 516 implants. Patient-reported outcome measures (PROMs) were reported in five studies involving 51 patients. Intraoperative adverse events/surgical approach details and preoperative radiological assessment were reported in 46 and 38 studies, respectively. The methodological quality of included studies was modest, predominantly consisting of case reports and noncontrolled case series with small numbers of patients. Most studies were Oxford Centre for Evidence Based Medicine grade IV. DISCUSSION: Access to good rehabilitation support is essential to achieving the good hearing outcomes and PROMs that can be expected by 12 months after implantation in most cases. There was a significant association between the radiological severity of otosclerosis and an increase in surgical and postoperative complications. Postoperative facial nerve stimulation can occur and may require deactivation of electrodes and subsequent hearing detriment. CONCLUSIONS: Hearing outcomes are typically good, but patients should be counseled on associated surgical complications that may compromise hearing. Modern diagnostic techniques may help to identify potentially difficult cases to aid operative planning and patient counseling. Further work is needed to characterize PROMs in this population.