Acoustic Neuroma Surgery Research Articles

LATEST ADVANCES IN FACIAL NERVE INTRAOPERATIVE MONITORING FOR VESTIBULAR SCHWANNOMA - UP TO DATE 2024

Introduction: Vestibular schwannoma, a benign tumor of the eighth cranial nerve, can be treated with radiosurgery, microsurgery, or observation. This study aims to present advances in intraoperative monitoring techniques for preserving facial nerve function during acoustic neuroma surgeries. By sharing the latest evidence, we hope to influence clinical practices for the benefit of patients. Methodology: Thus, we conducted a comprehensive literature review using the Scopus database, we searched for articles published from 2018 to 2023 using the keywords "facial paralysis," "acoustic neuroma," and "intraoperative monitoring." Results: The use of electromyographic parameters in the pre, intra, and post-resection monitoring of vestibular schwannoma provides valuable indicators of both the functional state of the facial nerve and the tumor adherence. This information plays a crucial role in making safe decisions regarding the extent of tumor resection while minimizing the risk of facial nerve damage during surgery. Supramaximal stimulation of the facial nerve in proximity to the tumor is of utmost importance to preserve facial function. However, the presence of a separate intermediate nerve poses challenges in accurately detecting false positives. Therefore, monitoring the facial nerve during surgery becomes essential to prevent potential injuries and to predict both short- and long-term outcomes. Conclusion: Intraoperative electrophysiological facial nerve monitoring is a crucial strategy to reduce postoperative facial paralysis. While the best technique is still under debate, several options exist to enhance monitoring efficacy and patient safety. By staying informed, clinicians can make better decisions to improve patient outcomes.

Translabyrinthine approach in acoustic neuroma surgery – case report

Introduction. Acoustic neuroma is a benign tumor that arises from the glial Schwann sheath junction of the vestibulocochlear nerve. It has an incidence of 1:100000 population. Despite the fact that this is a rare tumor, it accounts for approximately 6% of all intracranial tumors and 80% of tumors localized in cerebellopontine angle. Treatment of acoustic neuroma is represented by “Wait and Scan” monitoring, radiologic and surgical treatment. The latter remains the primary treatment for acoustic neuroma and consists of 3 main approaches: retrosigmoid approach, middle cranial fossa approach and translabyrinthine approach. Until now, in our country, acoustic neuroma surgery was done only by retrosigmoid approach. Case presentation. The first translabirinthine surgery for acoustic neuroma in our country was done on 09.12.2021 on a 60-year-old patient who, during preparation for cochlear implant surgery, was accidentally diagnosed with 3rd grade right acoustic neuroma, according to Koos classification. Patient had cophosis on the right ear and moderate hearing loss in the left ear. During the surgery, a gross total resection of the tumor was accomplished. The patient was discharged from the medical institution on 20.12.2021 in a satisfactory condition. Magnetic resonance imaging performed 3 months and 1 year after the surgery showed no complications or tumor remnants. Conclusion. The current report, which describes an accidental diagnosis of acoustic neuroma during preparation for a cochlear implantation surgery, resulted in acoustic neuroma surgery through the translabyrinthine approach. This serves as an eloquent example of why it is necessary to perform initially a magnetic resonance examination in cases of sensorineural hearing loss or tinnitus. The translabyrinthine approach in acoustic neuroma surgery allows for the removal of tumors of any size without affecting the brain, especially the cerebellum. In our case, where the patient had cophosis on the side of the tumor, this was the most appropriate surgical approach.

Surgical outcome of Acoustic Neuroma Surgery in a Malaysian Tertiary Hospital

INTRODUCTION: Acoustic neuroma (AN) or vestibular schwannoma, is a benign, slow-growing tumour that arises from the Schwann cell of the vestibular branch of the vestibulocochlear nerve. Treatment options are mainly conservative or surgical excision. The aim of this study is to describe the clinical characteristics of AN and the surgical outcomes in a Malaysian tertiary hospital. MATERIALS AND METHOD: Records of 73 patients who were diagnosed with AN from January 2008 until December 2019 were retrieved. All patients were analyzed for demographic data and clinical characteristics. In all 52 patients underwent AN surgery and had normal preoperative facial nerve function. A descriptive analysis was used for the surgical outcomes of each patient. RESULTS: The median age of patients was 51.5 (15.8 SD). Hearing levels pre-operatively were severe to profound in 74.0% of the patients, followed by moderate to severe in 15.1%, mild to moderate in 6.8%, and mild hearing loss in 2.7%. Retrosigmoid (48.1%) was the most common surgical approach used, followed by translabyrinthine (44.2%) and middle cranial fossa (MCF) (7.7%). The translabyrinthine approach is associated with the least incidence of facial nerve paresis postoperatively (21.2%) when compared to the retrosigmoid and middle cranial fossa approaches (40.4%). However, there was no significant association between surgical approaches and facial nerve outcome (p=0.07). CONCLUSION: AN surgery is a safe procedure, regardless of the surgical approach used. There was a significant relationship between tumour size and facial nerve outcome.

To the origins of surgery for acoustic neuromas

Acoustic neuroma is one of the most common tumors of the posterior cranial fossa. Its removal is always a challenge for the neurosurgeon and the patient. The history of surgery for acoustic neuromas is inextricably linked with the history of neurosurgery in general. The modern surgical community must know history and be able to use it. Only then will the development of surgery lead to the preservation of the quality of life of patients. In the history of surgery for acoustic neuromas, the stages of its development are clearly visible from the description of the clinical picture through the study of the anatomy of the cerebellopontine angle to modern microsurgical removal.

Clinical characteristics and risk factors for new-onset cervicogenic headache following elective craniotomy.

Clinical characteristics and risk factors for new-onset cervicogenic headache following elective craniotomy.

Assessment of the distribution and volume of air chambers around the inner auditory canal on high-resolution computed tomography scans of the temporal bone.

Assessment of the distribution and volume of air chambers around the inner auditory canal on high-resolution computed tomography scans of the temporal bone.

Untargeted Metabolomic Analysis in Endolymphatic Sac Luminal Fluid from Patients with Meniere's Disease.

Dysfunction of the endolymphatic sac (ES) is one of the etiologies of Meniere's disease (MD), the mechanism of which remains unclear. The aim of the present study was to explore the molecular pathological characteristics of ES during the development of MD. Metabolomic profiling of ES luminal fluid from patients with MD and patients with acoustic neuroma (AN) was performed. Diluted ES luminal fluid (ELF) samples were obtained from 10 patients who underwent endolymphatic duct blockage for the treatment of intractable MD and from 6 patients who underwent translabyrinthine surgery for AN. ELF analysis was performed using liquid chromatography-mass spectrometry before the raw data were normalized and subjected to subsequent statistical analysis by MetaboAnalyst. Using thresholds of P ≤ 0.05 and variable important in projection > 1, a total of 111 differential metabolites were screened in the ELF, including 52 metabolites in negative mode and 59 in positive mode. Furthermore, 15 differentially altered metabolites corresponding to 15 compound names were identified using a Student's t-test, including 7 significant increased metabolites and 8 significant decreased metabolites. Moreover, two differentially altered metabolites, hyaluronic acid (HA) and 4-hydroxynonenal (4-HNE), were validated to be upregulated in the epithelial lining of the ES, as well as in the subepithelial connective-tissue in patients with MD comparing with that in patients with AN. Among these differentially altered metabolites, an upregulated expression of HA detected in the ES lumen of the patients with MD was supposed to be associated with the increased endolymph in ES, while an increased level of 4-HNE found in the ELF of the patients with MD provided direct evidence to support that oxidative damage and inflammatory lesions underlie the mechanism of MD. Furthermore, citrate and ethylenediaminetetraacetic acid were detected to be decreased substantially in the ELF of the patients with MD, suggesting the elevated endolymphatic Ca2+ in the ears with chronic endolymphatic hydrops is likely to be associated with the reduction of these two chelators of Ca2+ in ES. The results in the present study indicate metabolomic analysis in the ELF of the patients with MD can potentially improve our understanding on the molecular pathophysiological mechanism in the ES during the development of MD.

Is There a Plateau to the Learning Curve for Acoustic Neuroma Resection?-Experience and Outcomes from a Single Interdisciplinary Team Over Thirty Years.

Objective The evolution of acoustic neuroma (AN) care continues to shift focus on balancing optimized tumor resection and control with preservation of neurological function. Prior learning curve analyses of AN resection have demonstrated a plateau between 20 and 100 surgeries. In this study of 860 consecutive AN surgeries, we investigate the presence of an extended learning curve tail for AN resection. Methods A retrospective cohort study of AN resections by a single interdisciplinary team between 1988 and 2018 was performed. Proportional odds models and restricted cubic splines were used to determine the association between the timing of surgery and odds of improved postoperative outcomes. Results The likelihood of improved postoperative House-Brackmann (HB) scores increased in the first 400 procedures, with HB 1 at 36% in 1988 compared with 79% in 2004. While the probability of a better HB score increased over time, there was a temporary decrease in slope of the cubic spline between 2005 and 2009. The last 400 cases continued to see improvement in optimal HB outcomes: adjusted odds of HB 1 score were twofold higher in both 2005 to 2009 (adjusted odds ratio [aOR]: 2.11, 95% confidence interval [CI]: 1.38-3.22, p < 0.001) and 2010 to 2018 (aOR: 2.18, 95% CI: 1.49-3.19, p < 0.001). Conclusion In contrast to prior studies, our study demonstrates the steepest growth for learning, as measured by rates of preservation of facial function outcomes (HB 1), occurs in the first 400 AN resections. Additionally, improvements in patient outcomes continued even 30 years into practice, underlining the importance of lifelong learning.

Retracted: Analysis of Related Factors Affecting Facial Nerve Function after Acoustic Neuroma Surgery.

[This retracts the article DOI: 10.1155/2022/5194566.].

Prediction of hearing preservation after acoustic neuroma surgery based on SMOTE-XGBoost.

Prior to the surgical removal of an acoustic neuroma, the majority of patients anticipate that their hearing will be preserved to the greatest possible extent following surgery. This paper proposes a postoperative hearing preservation prediction model for the characteristics of class-imbalanced hospital real data based on the extreme gradient boost tree (XGBoost). In order to eliminate sample imbalance, the synthetic minority oversampling technique (SMOTE) is applied to increase the number of underclass samples in the data. Multiple machine learning models are also used for the accurate prediction of surgical hearing preservation in acoustic neuroma patients. In comparison to research results from existing literature, the experimental results found the model proposed in this paper to be superior. In summary, the method this paper proposes can make a significant contribution to the development of personalized preoperative diagnosis and treatment plans for patients, leading to effective judgment for the hearing retention of patients with acoustic neuroma following surgery, a simplified long medical treatment process and saved medical resources.

Symptom: Runny Nose Six Years After Acoustic Neuroma Surgery

Symptom: Runny Nose Six Years After Acoustic Neuroma Surgery

Analysis of Related Factors Affecting Facial Nerve Function after Acoustic Neuroma Surgery.

Objective To investigate the factors affecting facial nerve function after acoustic neuroma surgery and to provide theoretical reference for clinicians to preserve facial nerve function better after surgery. Methods A retrospective cohort study was conducted to analyze the correlation between postoperative facial nerve function and surgical approach, age, sex, tumor size and adhesion degree of facial nerve in 152 patients with acoustic neuroma. Results In the choice of surgical approach, there was no significant difference in the anatomy of the complete facial nerve in labyrinth path, retrosigmoid sinus path, and middle cranial fossa path. There was no statistically significant difference between the middle cranial fossa path and the retrosigmoid sinus path in facial nerve function preservation 7 days after surgery. The difference between middle cranial fossa path and labyrinthine path was statistically significant (P < 0.01). There were statistically significant differences between labyrinth path and retrosigmoid sinus path (P < 0.05). Logistic multivariate regression analysis showed that the operative approach and the degree of adhesion between tumor and facial nerve were the risk factors affecting functional preservation of facial nerve 7 days after surgery. Age and the degree of adhesion between tumor and facial nerve were the risk factors for functional preservation of facial nerve 1 year after operation. Conclusion The facial nerve function injury in patients with acoustic neuroma may be related to the choice of surgical approach, the adhesion degree of tumor and facial nerve, and their age. Clinicians need to comprehensively evaluate the risk factors before surgery, so as to achieve individualized treatment to protect the integrity of postoperative facial nerve function of patients.

Analysis of readmissions data among frail and non-frail patients presenting for acoustic neuroma

The incidence of acoustic neuromas in the United States is 1.09 per 100,000 with 23,739 newly diagnosed cases in the years 2004 to 2010. Because the recent literature has supported that frailty can serve as a more accurate predictor of patient outcomes when evaluated with age, and is an important variable to consider in the course of patient treatment. The objective of this study was to compare the outcomes of frail patients who had undergone surgery for acoustic neuroma with their non-frail counterparts.The authors conducted a retrospective cohort study of geriatric patients receiving cranial neurosurgery for acoustic neuroma between 2016 and 2017 by using the Nationwide Readmission Database. A total of 396 frail patients and 402 non-frail patients were identified through the database of undergoing surgery for acoustic neuroma. Frail patients had statistically higher rates of readmission (p < 0.01), post-operative infection (p < 0.01), facial paralysis (p < 0.01), urinary tract infection (p < 0.01), hydrocephalus (p < 0.01), and dysphagia (p < 0.01). These post-op morbidities likely led to the increased length of stay (p < 0.01), non-routine discharge (p < 0.01), and all payer cost seen in frail patients (p < 0.01). However, no significant difference was found between frail and non-frail patients with regards to CSF leak, post hemorrhagic anemia, myocardial infarction, and mortality. Patient frailty status is a significant predictor of poor outcomes in the postoperative sequelae of acoustic neuroma surgery. Further, models including patient frailty plus age outperformed those using age alone for prediction of several postoperative complications.

The Strategy of Facial Nerve Preservation in Acoustic Neuroma Surgery via Suboccipital Retrosigmoid Approach

Acoustic neuroma is a common intracranial tumor, with a prevalence of 80~90% in the lesions of cerebellopontine angle. Microsurgical removal remains its main therapy, and the retrosigmoid approach continues to be the most widely employed strategy for the surgical resection of acoustic neuromas, with preservation of facial nerve to be the important goal. In order to preserve the facial nerve, the facial nerve's function should be evaluated accurately before and after the operation. The course of the facial nerve and its variation in cerebellopontine cistern and internal auditory canal should be well understood. Adequate drilling of the posterior wall of the internal auditory canal is necessary. Sufficient decompression of intracranial pressure and the tumor is imperative. The principle of subperineural and bidirectionary dissection should be followed. The use of bipolar coagulation should decrease to the greatest extent, and facial nerve monitoring should be used throughout exposing and removal of the acoustic neuroma.

The role of gold weight implants in the management of paralytic lagophthalmos.

Background/aimThe study aims to evaluate the usage of gold weight implants and monitor complaints and comfort of patients.Materials and methodsA hundred and ninety-one implantations performed between January 2009 and January 2019 were analyzed. Seventy-eight patients included in this study The average age of the patients was 51.3 ± 14.5 years. Forty-five (57.7%) of them were male and 33 (42.3%) female. Patient satisfaction was measured with a questionnaire containing the most common complaints related to gold weight in the literature through telephone surveys.ResultsThe average follow-up time was 74.5 months. Ninety-three-point-five percent of subjects had operational causes, among which the most widespread was acoustic neuroma (44.9%). The average time between facial paralysis and implantation was 141.1 days. Implantation was performed 26.6 days on average after acoustic neuroma surgery and 3.2 days on average after temporal zone malignancy surgery. Thirty-eight patients had their implants removed over either complication (n = 14) or recovery (n = 24). Recovery was the fastest after facial nerve decompression (mean= 4.75 ± 3.6 (2–10) months) and the slowest after 7–12 cranial nerve transfer (mean= 18.3 ± 8.2 (3–31) months). Twenty-six-point-nine percent (n = 21) of patients had complications, of which the most common was extrusion (n = 10). The overall satisfaction rate was 88.5% with the highest in visual acuity and the lowest in continuous requirement for artificial tear. ConclusionThe gold weight implantation is an effective, reversible, and easy procedure significantly reducing complaints regarding paralytic lagophthalmos. Early implementation may be beneficial for ocular complications. A dynamic facial reanimation could terminate need of implant.

Impact of extent of internal acoustic meatus tumor removal using translabyrinthine approach for acoustic neuroma surgery

Many studies have investigated the surgical outcome and predictive factors of acoustic neuroma using different approaches. The present study focused on large tumors due to the greater likelihood of internal acoustic meatus involvement and the greater application of surgical intervention than radiosurgery. There have been no previous reports on outcomes of internal acoustic meatus tumor removal. We investigated the impact of the extent of internal acoustic meatus tumor removal using a translabyrinthine approach for large acoustic neuroma surgery and predictive factors of tumor control. This retrospective study reviewed 104 patients with large cerebellopontine angle tumor >3 cm treated by translabyrinthine approach microsurgery. Predictive factors of postoperative facial palsy, tumor control, and extent of internal acoustic meatus tumor removal were assessed. The mean tumor size was 38.95 ± 6.83 mm. Postoperative facial function showed 76.9% acceptable function (House-Brackmann grade 1 or 2) six months after surgery. The extent of internal acoustic meatus tumor removal was a statistically significant predictor factor of poor postoperative facial function. Younger age, larger tumor size needing radiosurgery, and more extensive removal of tumor were associated with better tumor control. More extensive internal acoustic meatus tumor removal was associated with poor postoperative facial function and better tumor control.

Long-term Dysphagia following Acoustic Neuroma Surgery: Prevalence, Severity, and Predictive Factors

Abstract Background Acoustic neuroma (AN) may compress the cerebellum and brainstem and may cause dysfunction of bulbar cranial nerves. Objective To describe swallowing function outcomes in the late postoperative period after AN surgery. Methods This cohort study included patients operated on between 1999–2014, with a mean follow up of 6.4 ± 4.5 years. The swallowing function was assessed through the functional oral intake scale (FOIS). The primary outcome was defined by scores 5 to 1, which implied oral feeding restriction or adaptation. Risks factors were identified through multivariate logistic regression. Results 101 patients were evaluated. As many as 46 (45.5%) presented dysphagia on the late postoperative period. Women comprised 77.2%, and the mean age was 47.1 ± 16.0 years (range 19–80). Dysphagic patients presented more type II neurofibromatosis (NF II) (32.6% vs. 10.9%, p = 0.007), larger tumors (3.8 ± 1.1 vs. 3.1 ± 1.0 cm, p &lt; 0.001), partial resection (50.0% vs. 85.5%, p &lt; 0.001) and needed more surgeries (≥2, 39.1% vs. 18.2%, p = 0.019). Important peripheral facial palsy (PFP) (House–Brackmann [HB] grade ≥3) was present before the surgery on 47.5% and worsened on 55.4%. Postoperative PFP (p &lt; 0.001), but not preoperative PFP, was predictive of postoperative dysphagia. On multivariate analysis, the following factors were risk factors for dysphagia: NF II (OR 5.54, p = 0.034), tumor size (each 1 cm, OR 2.13, p = 0.009), partial resection (OR 5.23, p = 0.022) and postoperative HB grade ≥3 (OR 12.99, p = 0.002). Conclusions Dysphagia after AN surgery is highly correlated to postoperative facial motor function. NF II, tumor size, and extent of resection were also predictive of this morbidity in the late postoperative period.

Electrophysiological mapping and assessment of facial nerve functioning during acoustic neuroma operations.

BackgroundElectrophysiological monitoring is used routinely to protect the facial nerve during acoustic neuroma surgery. This study aimed to clarify the relationship between the facial nerve’s electrophysiological monitoring parameters and its function after surgery.MethodsFifty-two patients with acoustic neuroma who underwent surgery were included. After localizing the facial nerve, its monitoring results during surgeries performed at our center were analyzed. Postoperative nerve functioning was correlated with the stimulation threshold of the facial nerve’s proximal segment, proximal-to-distal amplitude ratio of the facial nerve, and proximal stimulation amplitude. Receiver-operating characteristic curves of the three parameters were calculated.ResultsElectrical stimulation accurately described the facial nerve’s anatomic distribution after the depth of anesthesia was assessed via accessory nerve stimulation. The data recorded after resection showed that a higher proximal-to-distal amplitude ratio was associated with better facial nerve functioning (P=0.037). A lower stimulation threshold of the proximal segment correlated with better facial nerve functioning (P=0.038).ConclusionsThe most sensitive index to predict postoperative nerve functioning is the facial nerve’s proximal-to-distal amplitude ratio. Accessory nerve stimulation can determine the appropriate depth of anesthesia, Electromyography (EMG) monitoring of the facial nerve during acoustic neuroma surgery can protect it effectively.

Peripheral Inflammatory Blood Markers in Diagnosis of Glioma and IDH Status.

Objective Gliomas are the most common intracranial tumors. Histopathology and neuroimaging are the main modalities used for diagnosis and treatment response monitoring. However, both are expensive and insensitive methods and can cause neurological deterioration. This study aimed to develop a minimally invasive peripheral inflammatory biomarker for diagnosis of glioma, its grade, and isocitrate dehydrogenase (IDH) status. Materials and Methods Patients undergoing surgery for glioma, acoustic neuroma, and meningioma between January 2019 and December 2019 were included. Preoperative neutrophil/lymphocyte ratio (NLR), derived NLR (dNLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio (LMR), eosinophil/lymphocyte ratio (ELR), and prognostic nutritional index (PNI) were calculated. Histopathology and immunohistochemistry (IHC) staining were done postoperatively. Results A total of 154 patients of glioma, 36 patients of acoustic neuroma, 58 patients of meningioma, and 107 healthy controls were included. dNLR showed the maximum area under the curve (AUC) (0.656639) for diagnosis of glioma from other tumors and among combinations. dNLR +NLR showed the maximum AUC (0.647865). Maximum AUC for glioblastoma multiforme (GBM) versus other grades and among combinations was shown by NLR (0.83926). NLR + dNLR had the maximum AUC (0.764794). NLR showed significant p value in differentiating IDH wild from IDH mutant GBM. Conclusion dNLR has the maximum diagnostic value in diagnosing glioma from other tumors. NLR (AUC = 0.83926) showed the highest accuracy for GBM diagnosis and may be a parameter in predicting the grade of glioma; also, it has maximum diagnostic value in differentiating IDH wild GBM from IDH mutant GBM. These peripheral inflammatory parameters may prove to be sensitive and cost-effective markers for glioma diagnosis, predicting grade of glioma, monitoring of treatment response, and in predicting recurrence.

The Transmastoid Retrolabyrinthine Approach in Acoustic Neuroma Surgery: Our Experience in 189 Patients.

This study aimed to describe our experience with the retrolabyrinthine or infralabyrinthine approach in acoustic neuroma surgery, and to discuss its advantages, limitations, complications, and the outcomes of hearing and facial function preservation. This study was a retrospective analysis of all acoustic neuroma cases, operated with a retrolabyrinthine approach in our hospital. This study was conducted at a tertiary university hospital. In total, 189 patients underwent hearing preservation and acoustic neuroma surgery, operated through the retrolabyrinthine approach, in our department. The average age was 43.6 years; there were 105 women and 84 men. All patients had unilateral tumors, 99 occurring in the right ear and 90 in the left ear. A retrolabyrinthine approach was performed in all 189 patients to remove vestibular schwannoma. All tumors graded I and II using Koos tumor grading with serviceable hearing when the speech reception threshold (SRT) was better than 50 dB, and word recognition scores of 50% or higher. Considering the 189 patients, good exposure of the internal auditory canal was possible in all patients, with total removal of the tumor in all patients, even though it was necessary to sacrifice the posterior canal in 12 of the cases, all classified as Koss II. Hearing was preserved in 49.73% of patients; 1% had permanent grade II House-Brackmann facial paralysis. The retrolabyrinthine approach showed security during facial nerve manipulation, small chance of morbidity, and good proportion of hearing preservation when tumor are up to Koss I and II classification.