Chorda Tympani Injury Research Articles

Comparison of Endoscopic and Microscopic Surgery for the Treatment of Acquired Cholesteatoma by EAONO/JOS Staging.

Cholesteatoma is a benign tumor of the middle ear. Tympanoplasty is performed to remove cholesteatoma, prevent recurrence, and avoid complications. Previously, microscopy was used for tympanoplasty; however, endoscopy has become increasingly popular for this procedure. The effectiveness of endoscopy and the appropriate candidacy for endoscopic ear surgery remain controversial. In this retrospective chart review study, we enrolled 107 patients with cholesteatoma who underwent tympanoplasty and compared the microscopic approach (71 patients) and the endoscopic approach (36 patients) at different stages to clarify the benefits of using endoscopy and to determine candidacy for endoscopic ear surgery. Approach selection, complication rate, recurrence rate, and postoperative hearing threshold were compared between microscopic and endoscopic approaches in stages I, II, and III. Endoscopy was used more often than microscopy for early-stage (stage I) cholesteatoma (p = 0.005) and less frequently for advanced-stage (stage II) cholesteatoma (p = 0.02). Endoscopy surgery resulted in chorda tympani injury less often than microscopic surgery (p = 0.049); however, there were no significant differences between these two groups in terms of recurrence rate or postoperative hearing outcome. Endoscopy is particularly useful for early-stage cholesteatoma, and both approaches show no difference in hearing outcome in stage I and II; nevertheless, further research is required to determine an appropriate approach for more advanced stages (stage III).

Microscopic versus Endoscopic Stapes Surgery – A Meta-Analysis

Abstract Background The microscope is the conventional method used by ear surgeons to view the middle ear structures, allowing for binocular vision and the freedom of both hands. Its main disadvantage is the need for an unobstructed, direct view of the operating area. The end-aural incision, drilling of the bony auditory canal, and regular repositioning of the patient and the surgeon are a few examples of how the operation has to adapt to the microscope. Nevertheless, the microscope has proven itself as the tool of choice in stapes surgery with reliable outcomes. Objective to compare endoscopic and microscopic interventions in stapes surgery regarding intraoperative and post-operative outcomes. Patients and Methods The review was a meta analytic & systematic review that included randomized controlled trials (RCT), case series and retrospective studies which studied the comparison of microscopic and endoscopic stapes surgery, 15 articles published between 2014 and 2020 were included in our study. Data Sources Medline databases (PubMed, Medscape, ScienceDirect. EMF-Portal) and all materials available in the Internet till 2020. Results Our results showed that the injury to the chorda tympani nerve was significantly higher in microscopic vs endoscopic groups. And also as regard the operative times, it was significant longer in microscopic vs. endoscopic groups. But there is no significant difference as regarde pain, dizziness, perforation of tympanic membrane, delayed conductive hearing & post-operative Air- bone gap improvement and taste disturbance between both groups. Conclusion Endoscopic stapes surgeries are technically feasible, safe and promising. Overall, our study indicates endoscopic and microscopic stapes surgery has similar audiological success, with some data suggesting a lower risk of chorda tympani injury and postoperative taste disturbance with the endoscope. Endoscopic stapes surgery appears to be a reasonable alternative to microscopic stapes surgery, with similar complications (chorda tympani nerve injury, pain, Perforation of tympanic membrane, taste disturbance, Dizziness, and delayed conductive hearing). Shorter operative times shorter and lower postoperative air-bone gap were found in endoscopic stapes surgery. Superior visibility with the endoscope was consistently reported in all the studies. This meta-analysis of the current evidence supports the use of endoscopic techniques for stapes surgery.

Modified stapes surgery for otosclerosis: An evaluation of auditory results and postoperative complications.

The senior author Shiao, had introduced a modified version of the traditional stapes surgery, called minimally traumatic stapes surgery (MTSS), and explored its effectiveness in reducing postoperative vertigo. However, MTSS exhibited no significant breakthrough in terms of audiometric results. Building upon the original MTSS through slight modifications and the use of the Medtronic Big Easy ® Piston as the prosthesis, this study evaluates a refined version of the original MTSS technique. In particular, this research sought to investigate the impact of this refined approach on hearing outcomes and postoperative complications among patients diagnosed with otosclerosis. This research comprehensively examined the medical records of individuals diagnosed with otosclerosis who underwent MTSS. The postoperative outcomes assessed encompassed hearing outcomes and the occurrence of any new complications. Overall, 95 patients diagnosed with otosclerosis (comprising 106 affected ears) underwent MTSS. Significant improvements in both the average air conduction threshold (40 ± 16.82 dB after vs 60 ± 14.56 dB before surgery; p < 0.0001) and average air-bone gap (11.99 ± 7.24 dB after vs 29.65 ± 9.47 dB before surgery; p = 0.003) were observed after the surgery. Conversely, no significant change in the average bone conduction threshold was observed after the procedure (28 ± 13.81 dB after vs 29 ± 12.31 dB before surgery; p = 0.149). Among the 106 affected ears, 102 showed postoperative air-bone gap measurements <20 dB, indicating an impressive 96.2% overall hearing improvement. Notably, only a few postoperative complications were observed, including vertigo, chorda tympani injury, facial weakness, and a slight hearing deterioration. The refined MTSS technique promoted significant postoperative hearing improvements with minimal complications. This approach showed potential for addressing the surgical challenges in Asian patients with otosclerosis, emphasizing the importance of further research on this advanced procedural method.

Primary Endoscopic Stapedotomy

Background: Otosclerosis is a progressive disease of the otic capsule which presents with conductive hearing loss with an intact tympanic membrane. The description of the disease was first given by Valsalva in 1704. Since then, several techniques are described for otosclerosis. All these procedures have traditionally been performed with microscope. New modifications of surgical techniques have been introduced time to time. The concept of minimally invasive surgical techniques has sprung up lately. Recent advances in optics such as high-definition endoscopes have revolutionized the surgeries in otology. Aim: The study aimed to study the feasibility of primary endoscopic stapedotomy. Objectives: (1) The objectives of the study were to evaluate Air-bone gap (ABG) closure in primary endoscopic stapedotomy and (2) to study intra- and post-operative complications in primary endoscopic stapedotomy. Methodology: Thirty patients with otosclerosis underwent stapedotomy using the standard 0.4 mm 18 cm endoscope and high-definition camera system. Results: Of the 30 cases, 17 were males and 13 were females, with a mean age of 39.84 years. A minimal removal of posterosuperior bony canal wall was required in 21 (70%) cases. The average operative time was 65 min. Among intraoperative complications, chorda tympani injury was seen in 2 (6%) cases, and incus subluxation and stapes footplate subluxation in 1 (3%) case each. Pure-tone audiograms done at an interval of 4 months demonstrated improvement across the three speech frequencies (500–2000 Hz) (50.2 dB vs. 23.7 dB). The average postoperative ABG was within 10 dB in twenty (66%) ears and between 10 and 25 dB in the rest ten (33%) ears. Conclusion: Endoscopic stapedotomy is a good alternative tool to conventional operating microscope. It offers better visualization, less trauma while elevating tympanomeatal flap flap, lesser bone curettage, and provides equivalent results.

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.

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. 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. 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. Netherlands Trial Register NL9791. Registered on 10 October 2021.

Outcome of classical and reversal stapedotomy in otosclerosis

Classical and reversal stapedotomy both are exclusively done in otosclerosis but definite information regarding surgical advances, postoperative results, complications and information about how and in which patients these surgical techniques should exclusively be used are a source of continuous discussions. This prospective observational study was conducted in the Department of Otolaryngology-Head &amp; Neck Surgery, Bangabandhu Sheikh Mujib Medical University, Shahbagh, Dhaka from July 2019 to December 2020 o compare the outcomes of classical and reversal stapedotomy in patients with otosclerosis. Total 28 cases of otosclerosis who underwent stapedotomy were divided in to two groups i.e. Group A (classical stapedotomy) &amp; Group B (reversal stapedotomy) with 14 patients in each group. All patients were followed up post-operatively up to 3 months with Pure-tone audiometry (PTA). There is no significant difference between classical and reversal stapedotomy approach in terms of hearing improvement and complications. Chorda tympani injury was the main complication in both the groups. Regarding hearing gain and complications there was no significant difference between classical and reversal stapedotomy approach. BSMMU J 2022; 15(2): 121-126

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

ObjectivesThe aim of this study was to compare the incidence of chorda tympani nerve (CTN) injury between endoscopic and microscopic stapes surgery.MethodsThis 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.ResultsThe 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).ConclusionAltered 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.

Role of the endoscope in cochlear implantation: A systematic review.

To review the role of the endoscope in cochlear implantation (CI). MEDLINE, ScienceDirect, Google Scholar and the Cochrane Library databases, as well as other sources, were searched by two independent reviewers. Studies including patients undergoing either exclusively endoscopic or endoscopically assisted CI were eligible for inclusion. Endoscopic CI approaches and postoperative complications were the primary outcomes. Secondary endpoints included the degree of round window (RW) microscopic visualisation according to St Thomas' Hospital classification and type of cochleostomy for electrode insertion in the scala tympani (ST). Fourteen studies met the inclusion criteria comprising 191 endoscopic or endoscopically assisted CI cases. The endoscope was used for better visualisation of the RW across all included studies, facilitated the insertion of the electrode in the ST and spared a mastoidectomy in a number of cases. No facial nerve palsy was reported in any of the studies. The most common complication was external auditory canal/tympanic membrane tear followed by chorda tympani injury. The microscopic CI approach is still the gold standard. The endoscope facilitates the recognition of the RW area and leads to successful and safe implantation, particularly in difficult anatomical scenarios, ear malformations and advanced otosclerosis. Endoscopically assisted CI procedures offer the opportunity to avoid a posterior tympanotomy and reduce the risk of facial nerve injury. To date, the lack of long-term data does not permit the widespread adoption of completely endoscopic CI procedures without a mastoidectomy.

Endoscopic Stapedotomy: A Systematic Review.

Stapes surgery has evolved from its origins in 1956. Microscopic assisted stapedotomy remains the most common technique but the introduction of endoscopic ear surgery has led to some units using this new approach. The endoscope delivers a wide angled, contextual view of the stapes, and associated pathology. This systematic review provides a critical analysis of the current published endoscopic data, allowing comparison to the established microscopic technique. Six databases (PubMed, Medline, Cochrane database, AMED, EMBASE, and CINAHL) were searched for studies within the last 10 years. English language articles including 5 or more cases were included. Primary outcomes included audiological results and reported complications. Data was extracted according to PRISMA guidelines. Thirteen papers were identified comprising 361 endoscopic stapes surgeries. Postoperative temporary facial nerve weakness was reported in 3 patients (0.8%) which all resolved within 4 weeks. Chorda tympani injury occurred in 21 cases (5.8%) and vertigo in 61 (16.9%). The audiometric outcomes of endoscopic stapes surgery were available for 259 patients and showed air bone gap closure rates of 71.4% (0-10 dB), 25.9% (11-20 dB), 2.3% (21-30 dB), and 0.4% (>30 dB). Endoscopic stapes surgery has similar audiometric outcomes compared to the traditional microscopic approach with air bone gap closure values of <20 dB in 97.3% of cases. However, the complication rates of chorda tympani damage, postoperative dysguesia, and tympanic membrane perforation for endoscopic stapes surgery are high. Caution should therefore be taken before undertaking stapes surgery with the endoscopic technique. Further studies are required to prove superiority over well established existing microsurgical methods.

Endoscopic Stapedectomy: Collective Experience From a Large Australian Center.

Endoscopic stapes surgery is a technically demanding procedure that is increasing in popularity. Surgical outcomes and complication rates have been demonstrated to be comparable to traditional microscopic techniques. The surgical outcomes for patients undergoing stapes surgery performed by the Sydney Endoscopic Ear Surgery Research Group are presented. Retrospective review from prospectively gathered database. Tertiary referral centers. A retrospective case review of patients undergoing endoscopic stapes surgery performed by four surgeons between February 2015 and July 2019 was carried out. Sixty nine patients were identified, and assessed for demographics, functional results, and postoperative complications. Endoscopic stapedotomy. Postoperative hearing results. Sixty eight of 69 patients (98.6%) achieved an air-bone gap (ABG) closure of less than 20 dB. Sixty of 69 patients (87%) achieved and ABG closure of less than 10 dB. The average improvement of the ABG over four frequencies achieved was 26.5 dB (range, 0-61). Postoperative complications were infrequent and self-limiting. Six patients experienced dysgeusia without obvious chorda tympani injury, four patients developed short lived vertigo, and two patients experienced tinnitus. Endoscopically assisted stapes surgery represents a safe alternative to traditional microscopic techniques, with similar morbidity and audiological outcomes.

Endoscopic transcanal stapedotomy: Our experiences at a tertiary care teaching hospital of Eastern India

Introduction: Although operating microscope is used worldwide for stapes surgery, the use of endoscopes would provide much benefit such as good panoramic view of middle ear and easy accessibility of the oval window area, stapes, and facial nerve. Objective: We aimed to analyze our experiences of endoscopic transcanal stapedotomy performed at a tertiary care teaching hospital of Eastern India. Materials and Methods: This prospective study was done at the Department of Otorhinolaryngology between March 2017 and April 2019. The patients were diagnosed as having otosclerosis with fulfilling the selection criteria. All underwent endoscopic transcanal stapedotomy. Results: Out of 52 patients those underwent endoscopic transcanal stapedotomy, there were 28 females and 24 males. The mean age was 32.40 years. The mean operation time was 35.43 min. The mean preoperative air–bone gap (ABG) was 34.84 dB, whereas the mean postoperative ABG was 9.81 dB. Tympanomeatal flap tear was seen in one case. One case showed chorda tympani injury and two patients presented with vertigo after surgery. No other complications were seen after endoscopic stapedotomy. Conclusion: The important advantages of endoscopic stapedotomy are good-quality visualization with identification of vital parts of the middle ear cleft, minimal handling to the chorda tympani nerve with almost no curettage of the scutum. The development of endoscopic ear surgery techniques promises the change the way we approach for stapes surgery. The wide field view of endoscope helps the surgeon to visualize better the middle ear recess, especially oval window niche and stapes.

Endoscopic Versus Microscopic Middle Ear Surgery: A Meta-analysis of Outcomes Following Tympanoplasty and Stapes Surgery.

This meta-analysis compares the efficacy and safety of endoscopic and microscopic approaches to tympanoplasty and stapes surgery, two common middle ear procedures. A comprehensive electronic search of PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library was conducted for studies published from the year 1960 through June 2018. Article selection and screening proceeded according to the strategies outlined in the standard Preferred Reporting Items for Systematic Reviews and Meta-analysis statement. Studies were assessed for quality using the Newcastle-Ottawa Scale and the Jadad scale depending on the presence of randomization. Bias was analyzed using funnel plots. For each outcome measure, a forest plot was generated and a pooled relative risk or risk difference was calculated to assess significance. Twenty-one studies met the inclusion criteria, 16 tympanoplasty (1,323 ears) and 5 stapes surgery (283 ears). The nonrandomized studies scored moderately well but the randomized studies were of low quality with respect to the Newcastle-Ottawa Scale and the Jadad Scale, respectively. With respect to tympanoplasty, statistical analysis demonstrated that the endoscopic approach had significantly lower canalplasty rates, better cosmetic outcomes, and shorter operative times. Furthermore, endoscopic compared to microscopic methods were similar in terms of audiological outcome, graft success rate, and complication rate. Among stapes surgeries, the endoscopic approach demonstrated a significantly decreased incidence of postoperative pain and chorda tympani injury but was similar to the microscopic approach with respect to audiological outcome, postoperative dizziness, and operative time. Though the merits of endoscopic techniques are becoming more well known, there are still concerns regarding their efficacy and safety. An analysis of the current literature suggests that audiological, functional, and safety outcomes are similar, if not superior, for the endoscopic approach to both tympanoplasty and stapes surgery compared to the microscopic approach. With respect to tympanoplasty, patients undergoing the endoscopic approach had lower canalplasty rates, better cosmetic outcomes, and shorter operative times. Among stapes surgeries, patients in the endoscopic group had a lower incidence of postoperative pain and injury to the chorda tympani. This meta-analysis of the current evidence supports the use of endoscopic techniques for tympanoplasty and stapes surgery.

Delayed facial palsy after tympanomastoid surgery: A report of 15 cases

ObjectiveTo analyze potential etiology and outcomes of delayed facial palsy (DFP) after tympanomastoid surgery. MethodsFifteen cases of DFP out of 1582 cases after tympanomastoid surgery were reviewed, and the potential causes and outcomes were analyzed. Results9 out of 15 patients (60%) had fallopian canal dehiscence and facial nerve exposure in contrast to 323 of 1567 patients (20.6%) without DFP, with significant difference (P<0.01). Chorda tympani was cut or overstretched in 4 cases. There were two cases with herpes labialis and IgM antibody against varicella-zoster virus. All patients fully recovered within two months. ConclusionFallopian canal dehiscence and facial nerve exposure was a risk factor of DFP after tympanomastoid surgery, and chorda tympani injury and viral reactivation may be triggering factors of DFP. The outcomes DFP after tympanomastoid surgery were excellent.

Stapes Surgery Outcomes: The Practice of 35 Years

Stapes Surgery Outcomes: The Practice of 35 Years

Cutting the chorda tympani: not just a matter of taste

Chorda tympani injury as a complication of middle-ear surgery has been extensively studied with regard to its effects upon taste. However, the chorda tympani also carries parasympathetic fibres to the salivary glands of the oral cavity. To date, little has been reported about the effect of chorda tympani section upon salivary function. Tertiary care centre. We report a case series of three patients with bilateral chorda tympani lesions. Chorda tympani function was assessed using 'taste strips' and unstimulated sialometry. A careful history of oral symptoms was taken. All patients showed transient or permanent bilateral ageusia of the anterior two-thirds of the tongue, and a decreased resting salivary flow rate. In addition, all patients suffered from transient or persistent, distressing xerostomia. Taste disorders may occur after middle-ear surgery but they are mostly transient, even when the chorda tympani nerves are sectioned bilaterally. In contrast, bilateral chorda tympani lesions may lead to severe, persistent and distressing xerostomia. Based on this neglected aspect of chorda tympani function, we emphasise the importance of preserving the chorda tympani whenever possible.

Isolated chorda tympani injury following petrous temporal fracture

Petrous temporal fractures account for nearly a fifth of all skull base fractures but are associated with taste disturbance in only 2% of cases. Chorda tympani injuries almost invariably occur in association with other nerve injuries. We present a rare case of an isolated chorda tympani injury associated with a petrous temporal fracture. Our observations suggest that the gustatory fibres in this nerve are segregated into groups subserving different taste modalities.

Chorda tympani injury: Operative findings and postoperative symptoms

Chorda tympani injury: Operative findings and postoperative symptoms

Chorda tympani injury: Operative findings and postoperative symptoms

This study aims to assess whether operative findings of chorda tympani nerve (CTN) trauma correlate with postoperative symptoms. A prospective study was conducted over 2 years on 140 middle ear operations analyzing taste disturbances. The operations were subdivided into myringoplasty/tympanoplasty (56 cases), mastoidectomy (64 cases), and tympanotomy (20 cases). Twenty-one (15%) patients reported taste disturbance. Altered taste was most reported (n=15, 71%) with loss of taste reported by 29% (n=6). Symptoms were most observed in the tympanotomy group (45%). Stretching of the CTN was associated with more symptoms than nerve transection. Recovery was complete in 76% (n=16) of the symptomatic cases by 12 months. Patients who undergo middle ear surgery should be thoroughly counseled with respect to CTN injury and symptoms regardless of the type of damage to the nerve. This study highlights the high incidence of postoperative alterations in taste after middle ear surgery, especially in non-diseased ears, and that CTN transection results in fewer symptoms than CTN stretching.

11:40 AM: Chorda Tympani Injury Operative Findings and Post-Op Symptoms

11:40 AM: Chorda Tympani Injury Operative Findings and Post-Op Symptoms

Expression of Activating Transcription Factor 3 and Growth-associated Protein 43 in the Rat Geniculate Ganglion Neurons after Chorda Tympani Injury

The purpose of this study was to evaluate the degree of damage in the geniculate ganglion and its target organ as a result of chorda tympani (CT) injury. We performed unilateral transection of the rat CT and examined expression of the activating transcription factor 3 (ATF3), a neuronal injury marker, and the growth-associated protein 43 (GAP-43), a regeneration-associated molecule. The mean proportion of ATF3-immunoreactive (ir) neurons in the geniculate ganglion was: 32% at 3 days after CT injury, but these neurons were never detected in the naive ganglion. Using in situ hybridization, the mean percentage of GAP-43 mRNA-labeled neurons (signal: noise ratio S 10) was observed to have increased significantly to 60% for 1-7 days after CT injury, while that in the naive ganglion was <15%. The results of morphological studies using scanning electron microscopy and immunohistochemistry indicated that atrophic change and reduction of protein gene-product 9.5-ir fibers in the denervated papillae, mainly in the intragemmal region, were observed after CT injury. Increase in GAP-43 mRNA, suggesting CT axonal regeneration, may have a role in recovery from taste disorders. However, this regenerative process may be involved in abnormal activity in the axotomized neurons or the adjacent intact neurons and so one must not disregard the existence of injured geniculate ganglions when considering the treatment of diseases that cause CT injury.