Exoscope-Assisted Stapedotomy: Evaluation of Safety and Efficacy.

OBJECTIVE: Evaluate the safety and efficacy of exoscope-assisted stapedotomy. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary care neurotology clinic. PATIENTS: Adult patients with otosclerosis undergoing stapedotomy. INTERVENTIONS: Primary stapedotomy. MAIN OUTCOME MEASURES: Evaluation of audiologic outcomes, including pure-tone average, bone-conduction thresholds, word recognition score, and air-bone gap. Complications, need for scutum removal, and length of surgery were also evaluated. RESULTS: A total of 47 patients were identified, and 24 patients underwent surgery with the microscope and 22 with the exoscope. There were significant improvements in pure-tone average, mean bone-conduction thresholds, and air-bone gap for both groups. There was no difference in preoperative or postoperative audiologic status for either group. There was no difference in rates of dysgeusia, chorda tympani nerve damage, dizziness, or facial paresis in either group. CONCLUSIONS: This study indicates similar audiologic outcomes, complication profiles, and visualization when comparing exoscopic and microscopic stapedotomy. Demonstrated here, exoscopic stapedotomy can be safely performed in a transcanal manner.

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.

Comparison of dislocation rates of Teflon and Titanium stapes prostheses: a retrospective survival analysis on 855 patients.

BACKGROUND: Stapes prosthesis dislocation is the first cause of revision stapes surgery. To our knowledge, there is no data about stability of the incus attachment of manual crimped prosthesis of different materials. This study aimed to compare the dislocation incidence between titanium and fluoroplastic stapes prostheses. METHOD: A monocentric retrospective cohort study was conducted between January 2013 and June 2022 in a tertiary-care center. All patients that underwent a primary stapes surgery with manually crimped fluoroplastic or titanium prostheses were included. Prosthesis dislocation from the incus was identified intraoperatively or with CT scan. The incidence of stapedial prosthesis dislocation over time was estimated using the Kalbfleisch and Prentice survival analysis method. Other indications for revision surgery prior to prosthesis dislocation were considered as competing events. Differences in the cumulative incidence functions between the fluoroplastic group and the titanium group was assessed using the Gray's test. RESULTS: Eight hundred and fifty-five patients underwent primary stapes surgery during the study period. Fluoroplastic prosthesis was used in 758 (88.7%) cases and titanium prosthesis in 97 (11.3%) cases. Median follow-up was 51.7 months (28.4-80.1). Dislocation was observed in 23 (3.0%) patients with fluoroplastic prosthesis and none (0.0%) in the titanium group. The probability of prosthesis dislocation at two years after surgery was 3.5% in the Teflon group and 0.0% in the Titanium group. No significant difference was found in the cumulative incidence of prosthesis dislocation between the fluoroplastic group and the titanium group (p = 0.12). CONCLUSIONS: Despite lack of statistical power, our results suggest a trend in a more stable incus attachment of manually crimped titanium stapes prosthesis compared to fluoroplastic over time. Further prospective randomized studies could be valuable to assess our findings.

[Revision surgery after stapedectomy]. / Revisionsoperationen nach Stapesplastik.

Revision stapes surgery is considered to be significantly more demanding than primary stapes surgery, both in terms of the indication and the surgical approach. This article reviews common indications for revision after stapedectomy as well as the surgical approaches and intraoperative findings. A distinction is made between revision surgeries, which are usually carried out because of conductive hearing loss a long time after stapes surgery, and acute or subacute revisions that become necessary in the immediate postoperative course. With the shortening of postoperative observation times under inpatient conditions as a result of increasing economization and the associated shift of the immediate postoperative phase to the outpatient setting, the recognition of postoperative irregularities is also becoming increasingly important for otorhinolaryngologists in private practice, even if they do not perform these highly specialized interventions themselves.

The impact of injury of the chorda tympani nerve during primary stapes surgery or cochlear implantation on taste function, quality of life and food preferences: A study protocol for a double-blind prospective prognostic association study.

BACKGROUND: The chorda tympani nerve (CTN) is a mixed nerve, which carries sensory and parasympathetic fibres. The sensory component supplies the taste sensation of the anterior two-thirds of the ipsilateral side of the tongue. During middle ear surgery the CTN is exposed and frequently stretched or sacrificed, because it lacks a bony covering as it passes through the middle ear. Injury may cause hypogeusia, ageusia or altered taste sensation of the ipsilateral side of the tongue. To date, there is no consensus regarding which type of CTN injury (sacrificing or stretching), during middle ear surgery, leads to the least burden for the patient. METHODS: A double-blind prospective prognostic association study was designed in a single medical centre in the Netherlands to determine the effect of CTN injury on postoperative taste disturbance and quality of life. 154 patients, who will undergo primary stapes surgery or cochlear implantation will be included. The taste sensation, food preferences and quality of life of these patients will be evaluated preoperatively and at one week, six weeks and six months postoperatively using the Taste Strip Test, Electrogustometry, supplementary questionnaire on taste disturbance, Macronutrient and Taste Preference Ranking Task, Appetite, Hunger and Sensory Perception questionnaire and Questionnaire of Olfactory Disorders to assess the association of these outcomes with CTN injury. Evaluation of olfactory function will only take place preoperatively and at one week postoperatively using the Sniffin' Sticks. The patient and outcome assessor are blinded to the presence or absence of CTN injury. DISCUSSION: This study is the first to validate and quantify the effect of chorda tympani nerve injury on taste function. The findings of this study may lead to evidence-based proof of the effect of chorda tympani injury on taste function with consequences for surgical strategies. TRIAL REGISTRATION: Netherlands Trial Register NL9791. Registered on 10 October 2021.

Positive and negative post stapedotomy effects on cervical VEMP recordings; a STROBE analysis.

AIMS: The primary goal of the present study was to compare the pre- and post-stapedotomy elicitation and waveform characteristics of both air- and bone-conduction (AC-, BC-) cervical vestibular evoked myogenic potentials (cVEMPs) through an individualized approach. A possible association between audiological characteristics, such as AC- and BC- pure tone audiometry thresholds and air-bone gap and the production of cVEMPs before and after stapedotomy was also investigated. MATERIAL AND METHODS: Twenty-five ears were subjected to full audiological evaluation as well as AC- and BC-cVEMPs pre- and post-stapedotomy. Four subgroups were studied; consistently present/absent, post-operatively disappeared and restored cVEMPs. RESULTS: Post-stapedotomy changes in cVEMP elicitability did not reach significance for either AC-cVEMP (OR=5.41, 95% CI 0.88-33.36, P=0.06) or BC-cVEMP (OR=2.40, 95% CI 0.42-13.60, P=0.3). Normal or abnormal AC-cVEMPs were equally subject to post-operative changes (OR=1.95, 95% CI 0.32-12.01, P=0.5), as were BC-cVEMPs (OR=3.75, 95% CI 0.66-21.25, P=0.1). Neither the audiological characteristics nor the surgical outcome, in terms of ABG results, were relevant to the presence or absence of AC- and BC-cVEMPs before or after stapedotomy. CONCLUSIONS: The presumed changes brought to the sacculus by stapedotomy are minor and beyond the diagnostic abilities of either AC-cVEMPs or BC-cVEMPs, both in terms of cVEMPs elicitability and waveform characteristics. In individual cases, however, which may deserve further investigation, cVEMPs may reappear or disappear after stapedotomy probably following minor changes toward a lower or higher vestibular system resistance for pressure and sound transmission.

Cerebrospinal Fluid Leak During Stapes Surgery: The Importance of Temporal Bone CT Reconstructions in Oblique Anatomically Oriented Planes.

Stapes gusher is a massive flow of perilymph and cerebrospinal fluid leak that fills the middle ear immediately after surgical opening of the labyrinth, such as during stapedectomy. Stapes gusher usually occurs as the result of a congenital malformation that causes an abnormal communication between the perilymphatic space and the subarachnoid space involving the internal auditory canal or the cochlear duct. To date, the potential risk of stapes gusher cannot be assessed preoperatively, as there are not pathognomonic signs suggestive of this complication. However, high-resolution computed tomography scan (HRCT) of the temporal bone can provide information that may help recognizing patients at risk. Recently, an anatomic evaluation of the inner ear with oblique reformation at HRCT has been described. This reformation offers a new and more detailed topographic vision of temporal bone structures compared to the classic axial and coronal planes and may help identifying anatomical alterations otherwise not visible. In this article, we present a case of stapes gusher and the role of preoperative HRCT with oblique reformation in its prevention.

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.

Chorda tympani injury during endoscopic versus microscopic stapes surgery: a randomized controlled clinical trial.

OBJECTIVES: The aim of this study was to compare the incidence of chorda tympani nerve (CTN) injury between endoscopic and microscopic stapes surgery. METHODS: This randomized controlled clinical trial included 88 patients who were randomly divided into two groups: endoscopic stapedotomy group (n = 44) and microscopic stapedotomy group (n = 44). The incidence of chorda tympani nerve (CTN) injury after surgery was determined by both subjective taste testing and chemical taste tests, before and after surgery. The results were compared between the two groups. RESULTS: The total number of patients who were identified as having CTN affection (based on the chemical testing) was 16 out of 88 (18.2%). The incidence was significantly lower in the endoscopic group (n = 2) than the microscopic group (n = 14) (p = 0.019). CONCLUSION: Altered taste as a result of iatrogenic CTN injury can affect the patients' quality of life. Endoscopic ear surgery offers better visualization, less need for extensive manipulation of the chorda tympani, and consequently decreased incidence of CTN injury.

Subjective and Objective Taste Change After Stapes Surgery Systematic Review and Meta-Analysis.

INTRODUCTION: Iatrogenic injury to the chorda tympani (CT) is a well recognized, although potentially underestimated, consequence of stapes surgery. This study aims to review the currently available literature to determine the incidence and prognosis of taste disturbances in these patients. DATA SOURCES: PubMed, Embase, and Cochrane Library databases. METHODS: Databases were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Search terms included (chorda tympani OR gustatory OR taste OR chemosensory OR dysgeusia OR nervus intermedius) AND (ear surgery OR middle ear OR stapes OR stapedectomy OR stapedotomy). Patients with prospective data collection including preoperative data were further divided by methodology into "objective" and "subjective" assessments of taste dysfunction. A systematic review was performed for all included studies, with meta-analysis using a random-effects model was used for those with comparable methodology and patient populations. RESULTS: Initial search yielded 2,959 articles that were screened according to inclusion and exclusion criteria. Once duplicates were removed, seven studies were identified, representing 173 patients with subjective testing (all seven studies) and 146 with objective testing (five studies). Eighty of 173 patients (46.2%) noted a disturbance in taste at early follow-up, whereas as 26 of 173 (15.0%) noted long-term problems. Objective methodology and result reporting were heterogenous and not amenable to pooled meta-analysis for all studies included. CONCLUSION: Changes in taste occur relatively frequently after stapedectomy. Surgeons should continue to counsel prospective patients as to the risks of both short- and long-term taste disturbances.

Unexpected Branch Malformation of the Facial Nerve during Stapes Surgery: Comparison between Intraoperative and Radiographic Findings.

The aim of this study was to determine the prevalence of facial nerve (FN) bifurcation in patients who undergo stapes surgery, and to ascertain the correlation between the intraoperative and radiographic findings in cases where an unexpected branch malformation for patients undergoing stapes surgery. Patients who underwent stapes surgery were retroactively examined for confirmed FN bifurcation. Among the 887 patients, 10 had a bifurcated FN confirmed during surgery and had a preoperative high-resolution computed tomography (HRCT) scan. The HRCT scans were examined by two radiologists who were blinded to the operational findings. The diagnostic accuracy of HRCT imaging was examined along with their preoperative audiometry. In total, 887 patients underwent stapes surgery and among them the prevalence of FN bifurcation was 1.13%. These 10 patients had a 1:1 male-female ratio with a mean age of 17.9 ± 7.0 years. From a surgical review, all cases had bifurcation at the horizontal segment of FN, including 1 case of FN trifurcation. The diagnostic difference between HRCT imaging and intraoperation observations for malformations in the middle ear varies widely depending on the location, ranging from 0% to 90%. The prevalence of incus and stapes malformations was high in both imaging and operation findings (≥60%). The detection rate of abnormal positioning and bifurcation of the FN during HRCT imaging was 30% and 0%, respectively. The mean air-bone gap hearing threshold for patients was significantly improved from 42.3 dB preoperatively to 15.6 dB postoperatively without any complications. These results showed that it is extremely difficult to predict the FN bifurcation prior to surgery with a detection rate of 0%. The diagnostic difference between HRCT imaging and intraoperation observations for malformations of different parts of the middle ear varies widely. These results highlight the importance of being vigilant in regard to FN anatomical variation during stapes surgery for any unexpected malformations that are not detected during HRCT evaluation. In addition, the surgical outcomes for these patients were optimal when treatment was performed by senior surgeons.

Predictive Patient Factors for Poor Outcomes Following Stapedotomy for Otosclerosis.

OBJECTIVE: To assess patient-related risk factors associated with poor outcomes following stapedotomy for otosclerosis. STUDY DESIGN: Retrospective study. SETTING: Academic tertiary care center. METHODS: Retrospective chart review of 107 patients with otosclerosis who underwent stapedotomy between 2013 and 2020. Demographics, comorbidities, and smoking history were obtained. Preoperative and postoperative audiogram data, including air-bone gap (ABG), and complications were collected. Data were analyzed using t test and Fischer's exact test for continuous and categorical variables, respectively. RESULTS: Among 107 patients, 29.5% were smokers and 70.1% non-smokers. Overall, the average ABG-gain 3-months postoperatively was 20.2 dB, and intraoperative and postoperative complications were 3.74 and 13.1%, respectively. Those with a history of otologic procedures had a lower mean ABG gain at 3 months compared with those without previous otologic surgery (14.4 dB versus 20.4 dB, p = 0.018). The average ABG gain at 3-months was not significantly different between those with current, former, or no smoking history, respectively (13.5 versus 18.1 versus 20.6, p = 0.08). Current smokers had 4.5 times greater odds of complications compared with non-smokers, although not statistically significant (95% CI 0.9-22.8, p = 0.1912). CONCLUSION: Age and history of otologic procedures as independent risk factors did impact hearing outcomes among our patient cohort; however, smoking history did not. Future prospective studies are required to further investigate complication rates by various modifiable risk factors, such as smoking status, body mass index (BMI), and obstructive sleep apnea (OSA) with continuous positive airway pressure (CPAP) use, for stapedotomy surgeries.

Taste impairment after endoscopic stapes surgery: Do anatomic variability of chorda tympani and surgical technique matter? : Post-operative dysgeusia after EStS.

PURPOSE: To investigate how the anatomical configuration of the oval window region (OWR) influences the management of the chorda tympani (ChT) and the curetting of adjacent bony structures, in a setting of patients undergoing endoscopic stapes surgery (EStS); to assess the incidence of early and late post-operative dysgeusia and to identify anatomical and surgical factors influencing taste function after EStS. METHODS: Surgical video recordings of 48 patients undergoing EStS for otosclerosis between January 2019 and July 2020 were retrospectively revised, to classify the anatomical variability of selected middle ear structures and the management strategies for the ChT. Clinical records of included patients were reviewed for subjective early and late post-operative taste impairment using a 5-point Likert-scale. RESULTS: The most common configuration of the OWR was type III. The extension of the bony curettage resulted inversely proportional to the exposure of the OWR. The long-term rate of preserved post-operative taste function was 85%. Displacement of the ChT was necessary in 43/48 cases (90%), mostly medially (36/48, 75%). CONCLUSION: Bone curetting during EStS does not correlate with post-operative taste impairment. Despite 100% ChT preservation rate, dysgeusia may occur in a minority of patients, with no apparent relationship to anatomical variability or intraoperative management of the ChT. The use of CO2 laser could have a role in increasing the risk of post-operative dysgeusia after EStS.

The Impact of the Frequency-Specific Preoperative Sensorineural Hearing Loss to Postoperative Overclosure of Bone Conduction in Stapedotomy.

OBJECTIVE: To evaluate the frequency-specific relationships between the preoperative sensorineural hearing loss and postoperative overclosure of bone conduction (BC) threshold after stapedotomy. METHODS: We conducted a retrospective analysis of 207 otosclerosis patients who underwent stapedotomy in our hospital. Pre- and postoperative audiometry were collected between patients with or without preoperative sensorineural hearing loss (SNHL) component (i.e., SNHL group and non-SNHL group, respectively). Overclosure rate (OR), deterioration rate (DR), and their significant values (i.e., SOR or SDR) were compared between the sub-groups at each frequency to access the frequency-specific outcomes. RESULTS: There were 69 patients in non-SNHL group and 138 patients in SNHL group. Postoperative success rate was similar in non-SNHL group and SNHL group. For frequency-specific outcomes, both the OR and SOR were significantly obvious in all SNHL subgroups than those in non-SNHL subgroups (p < 0.001), except at 4 kHz for SOR. Extent of overclosure and significant overclosure were more obvious in SNHL subgroups than those in non-SNHL subgroups (p < 0.01). The DR and SDR of BC were significantly obvious at 1k to 4 kHz in non-SNHL subgroups than those in SNHL subgroups (p < 0.01), however, not so for the extent of deterioration (p > 0.05). Frequency-specific success rate was similar at each frequency. CONCLUSION: Stapedotomy was efficient and safe in patients with or without SNHL component preoperatively. Frequency-specific overclosure effect was more obvious in all tone frequencies in SNHL subgroups than those in non-SNHL subgroups. For frequency-specific outcomes, about 50% BC with preoperative SNHL component at tone frequency meet postoperative significant overclosure effect, which was most obvious at low frequencies.

Primary stapedotomy: Influence of prosthesis diameter on hearing outcome.

OBJECTIVES: To evaluate the success rate of primary stapedotomy and to investigate the influence of prosthesis diameter on hearing outcome. MATERIAL AND METHODS: Retrospective medical chart review of 125 cases who underwent primary small fenestra stapedotomy, from January 2001 to December 2018. The study population was divided in two groups based on Teflon prosthesis diameter - .6mm (60%, N=75) and .4mm (40%, N=50). Pre- and postoperative (≥12 months) air-conduction (AC), bone conduction (BC) and air-bone gap (ABG) thresholds were compared. RESULTS: Postoperative ABG≤10dB and ≤20dB was achieved by 65.7% and 90% of the patients. A functional hearing (PTA-AC≤30dB) was achieved by 59.2% of patients. Sensorineural hearing loss (SNHL, worsening in BC-PTA>10dB) was identified in 7.2% of patients. Comparison of the .6mm- and .4mm-groups, revealed no differences regarding improvements in AC-PTA (22.4 vs. 20.7dB, p=.56), BC-PTA (3.4 vs. 2.3dB, p=.54) and ABG-PTA (19.1 vs. 18.4dB, p=.77). Hearing outcome evaluation identified similar postoperative success rate (.6mm, 79.7% vs. .4mm, 62%, p=.336) and comparable functional hearing (.6mm, 64% vs. .4mm, 52%; p=.197). The incidence of postoperative SNHL was similar between the two pistons (.6m, 5.3% vs. .4mm, 10%, p=.481). CONCLUSION: Primary small fenestra stapedotomy is an effective and safe procedure. A postoperative ABG within 10dB was achieved in 67.2% of patients and there was a reduced incidence of sensorineural hearing loss. Hearing outcome was not influenced by diameter of the selected prosthesis. Postoperative bone conduction hearing thresholds did not differ between the groups, which revealed no significant inner ear trauma caused by the larger piston. Although we did not find evidence to suggest one piston over the other, our results showed a trend toward better results with the larger prosthesis.