Functional Preservation Of Facial Nerve Research Articles

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.

Letter to the Editor Regarding “Postoperative Functional Preservation of Facial Nerve in Cystic Vestibular Schwannoma”

Letter to the Editor Regarding “Postoperative Functional Preservation of Facial Nerve in Cystic Vestibular Schwannoma”

In Reply to the Letter to the Editor Regarding “Postoperative Functional Preservation of Facial Nerve in Cystic Vestibular Schwannoma”

In Reply to the Letter to the Editor Regarding “Postoperative Functional Preservation of Facial Nerve in Cystic Vestibular Schwannoma”

Anatomical vs Functional Preservation of Facial Nerve in a case of Petrous Apex Meningioma

Abstract not available&#x0D; Bang. J Neurosurgery 2021; 10(2): 216-222

Postoperative Functional Preservation of Facial Nerve in Cystic Vestibular Schwannoma

To retrospectively analyze clinical and surgical data of a consecutive series of 26 patients with unilateral cystic vestibular schwannomas. Tumors were classified as type A (central cyst) and type B (peripheral cyst) and as small (tumor diameter <3 cm) and large (tumor diameter >3 cm). All patients underwent microsurgical removal via retrosigmoid approach. The course of the facial nerve (FN) was classified as anterior, anterior-inferior, anterior-superior, and dorsal to the tumor's surface. Mean patient age was 53.5 years. Mean tumor size was 3.2 cm. There were 22 cases classified as type A and only 4 as type B. Total or near-total resection (>95%) was achieved in 16 cases (61.5%), subtotal removal (90%-95%) was achieved in 9 cases (34.6%), and partial removal (<90%) was achieved in 1 case (3.9%). Position pattern of FN was anterior-inferior in 10 cases (38.4%), anterior-superior in 10 cases (38.4%), anterior in 23.2% of 6 cases. At hospital discharge, FN function was House-Brackmann grade I-V in 9 (36%), 10 (38%), 3 (12%), 3 (12%), and 1 (4%) patients; at final follow-up, House-Brackmann grades I, II, III, and IV accounted for 18 (72%), 6 (24%), 1, and 1 cases. During follow-up ranging from 6 months to 10 years, reoperation for growing of residue was never necessary. According to the literature and the results of our series, microneurosurgery of cystic vestibular schwannomas is associated with good outcomes in terms of extent of resection and FN function. In particular, long-term FN function is much more satisfactory than short-term function. In most cases, microsurgery represents the treatment of choice of cystic vestibular schwannomas.

Extra-Arachnoidal Dissection for Excision of Giant Vestibular Schwannomas: Improved Facial Nerve Preservation

Abstract INTRODUCTION Surgical excision of giant vestibular schwannomas with preservation of facial nerve function remains a challenge. A modified surgical technique using an extra-arachnoid plane of dissection and limited meatal drilling is described here with the goal of improving the rated of functional preservation of facial nerve. METHODS The clinical material was analyzed for two groups: Group A patients of giant vestibular schwannomas operated between 2002 and 2009 with the “standard” surgical technique, Group B- patients of giant vestibular schwannomas operated between 2009 and 2015 using the new technique of pure extra-arachnoid dissection and limited meatal drilling. RESULTS Group A: Of the 115 patients in this group, total excision was possible in 103 (89.5%), near total excision in 7 (6%) and partial excision in 5 (4.3%) patients. Anatomical preservation of 7th nerve was achieved in 87.8% of patients. House and Brackman grade 1 and grade 2 facial nerve function was present in 68 (59.1%) patients, grade 3 in 10 (8.7%), grades 4 and 5 in 11 (9.6%), and 26 (22.6%) had grade 6 facial nerve involvement. Group B: Of the 127 patients operated by this technique, details and long term follow-up was available for 98 patients. Total excision was achieved in 70 (71.4%) patients, near total excision in 9 (9.2%), and subtotal excision in 19 (19.4%) cases. Four patients had repeat surgery and 14 patients underwent gamma knife radiosurgery. At follow-up, 78 (79.5%) patients had grade 1 and 2 facial nerve involvement, while 20 (20.4%) patients continued to have a poor function (grade 3-5). CONCLUSION Extra-arachnoid dissection and limited meatal drilling resulted in an improved rate of functional facial nerve preservation.

Systematic review and meta-analysis of the technique of subtotal resection and stereotactic radiosurgery for large vestibular schwannomas: a "nerve-centered" approach.

OBJECTIVE During the last decade, the primary objective for large vestibular schwannoma (VS) management has progressively shifted, from tumor excision to nerve preservation by using a combined microsurgical and radiosurgical approach. The aim of this study was to provide a systematic review and meta-analysis of the available literature regarding the combined strategy of subtotal resection (STR) followed by stereotactic radiosurgery (SRS) for large VSs. METHODS The authors performed a systematic review and meta-analysis in compliance with the PRISMA guidelines for article identification and inclusion using the PubMed, Embase, and Cochrane databases. Established inclusion criteria were used to screen all identified relevant articles published before September 2017 without backward date limit. RESULTS The authors included 9 studies (248 patients). With a weighted mean follow-up of 46 months (range 28-68.8 months), the pooled rate of overall tumor control was 93.9% (95% CI 91.0%-96.8%). Salvage treatment (second STR and/or SRS) was necessary in only 13 (5.24%) of 18 patients who experienced initial treatment failure. According to the House-Brackmann (HB) grading scale, functional facial nerve preservation (HB grade I-II) was achieved in 96.1% of patients (95% CI 93.7%-98.5%). Serviceable hearing after the combined approach was preserved in 59.9% (95% CI 36.5%-83.2%). CONCLUSIONS A combined approach of STR followed by SRS was shown to have excellent clinical and functional outcomes while still achieving a tumor control rate comparable to that obtained with a total resection. Longer-term follow-up and larger patient cohorts are necessary to fully evaluate the rate of tumor control achieved with this approach.

Dorsal displacement of the facial nerve in acoustic neuroma surgery: clinical features and surgical outcomes of 21 consecutive dorsal pattern cases.

In acoustic neuroma surgery, the facial nerve (FN) course varies among patients, but a dorsal pattern is rarely observed. We retrospectively reviewed and classified 556 acoustic neuromas operated on via a lateral suboccipital retrosigmoid (LSO) approach into two groups: dorsal (group D) and non-dorsal (group ND). The clinical features and outcomes including functional preservation of the FN, the extent of tumor resection, and the retreatment rate were compared. Among 556 cases, 21 (3.8%) patients with dorsal patterns were identified. No significant differences in clinical features or preoperative status were noted between groups D and ND. No significant differences in functional FN preservation were found between groups D and ND in the immediate postoperative period (90.5 and 83.0%, respectively) or 1-year postoperatively (95.2 and 97.0%, respectively). Compared with group ND, the extent of tumor resection was significantly less (p < 0.0001) and the retreatment rate was significantly higher in group D (hazard ratio, 33.6; 95% confidence interval [CI], 11.7-96.1; p < 0.0001). In one dorsal pattern case, surgical resection was abandoned based on the intraoperative findings. Dorsal displacement of the FN was accurately predicted with preoperative imaging evaluations in just two cases. Functional preservation of the FN during acoustic neuroma surgery is achievable if the FN runs along the dorsal side of the tumor. However, a dorsal pattern, especially when the FN is broadened, is clearly associated with less complete tumor removal and a higher rate of retreatment than typical pattern cases.

Facial nerve preservation with preoperative identification and intraoperative monitoring in large vestibular schwannoma surgery

Microsurgery is an option of choice for large vestibular schwannomas (VSs). Anatomical and functional preservation of facial nerve (FN) is still a challenge in these surgeries. FNs are often displaced and morphologically changed by large VSs. Preoperative identification of FN with magnetic resonance (MR) diffusion tensor tracking (DTT) and intraoperative identification with facial electromyography (EMG) may be desirable for improving functional results of FN. In this retrospective study, eight consecutive cases with large VS (≥30 mm in maximal extrameatal diameter) were retrospectively studied. FN DTT was performed in each case preoperatively. All the cases underwent microsurgical resection of the tumor with intraoperative FN EMG monitoring. Correctness of prediction for FN location by DTT was verified by the surgeon's inspection. Postoperative FN function of each patient was followed up. Preoperative identification of FN was possible in 7 of 8 (87.5 %) cases. FN location predicted by preoperative DTT agreed to surgical finding in all the 7 cases. FN EMG was helpful to locate and protect the FN. Total resection was achieved in 7 of 8 (87.5 %). All FNs were anatomically preserved. All cases had excellent facial nerve function (House-Brackmann Grade I-II). FN DTT is a powerful technique in preoperatively identification of FN in large VS cases. Continuous intraoperative FN EMG monitoring is contributive to locating and protecting FNs. Radical resection of large VSs as well as favorable postoperative FN outcome is available with application of these techniques.

Functional outcome and postoperative complications after the microsurgical removal of large vestibular schwannomas via the retrosigmoid approach: a meta-analysis

For large (≥30mm) or giant (≥40mm) vestibular schwannomas (VSs) for which microsurgical removal is the main treatment option, complete tumour resection and the preservation of acceptable facial nerve function can be safely and successfully achieved via the retrosigmoid approach. We performed a meta-analysis to provide a reliable estimate of functional outcome and postoperative complications for patients treated surgically for large VSs. We conducted a comprehensive search in Pubmed, Embase and the Chinese National Knowledge Infrastructure (CNKI) databases to identify publications that included only patients in whom the VSs were >3.0cm in maximal diameter and microsurgically removed by a retrosigmoid approach. Pooled estimates of proportions with corresponding 95% confidence intervals were calculated using the Freeman-Tukey double arcsine transformation. This meta-analysis revealed that the pooled proportion of gross total resections was 79.1% (95% CI, 64.2-90.8%; I (2) = 95.4%). By combining microsurgical techniques with continuous electrophysiological monitoring, the anatomical preservation of the facial nerve at the end of surgery was achieved in 88.8% (95% CI, 83.6-93.2%; I (2) = 76.1%) of the patients. The pooled proportion of good postoperative facial nerve function (House-Brackmann (HB) grades I-II) was 62.9% (95% CI, 50.0-74.9%; I (2) = 91.1%). Cerebrospinal fluid leakage was reported in 7.8% (95% CI, 4.8-11.4%; I (2) = 49.8%) of the patients. The mortality rate was 0.87% (95% CI, 0.22-1.78%; I (2) = 4.9%). Our meta-analysis revealed that for large VSs, very favourable results can be obtained using the retrosigmoid approach with minimal mortality, especially with respect to anatomical and functional facial nerve preservation.

Therapeutic strategy for large vestibular schwannomas

Management of large vestibular schwannoma (VS) remains a difficult problem for which the extent of tumor resection and the role of radiosurgery continue to be the subject of debate. To develop an optimal therapeutic strategy for large VS, various treatment options within the avenues of microsurgery and radiosurgery were evaluated and compared. The authors carefully reviewed the clinical data of 50 surgical cases of large VS, defined as tumors with an average diameter over 3 cm in magnetic resonance imaging (MRI). All patients underwent microsurgery as the primary treatment. Gross total removal (GTR) was achieved in nine patients (18%), near total removal (NTR) in 8 (16%), radical subtotal removal (R-STR) in 31 (62%), and subtotal removal (STR) in 2 (4%). Among the 33 patients with R-STR and STR, eight had undergone adjuvant radiosurgery for the residual mass. Average tumor volume and diameter were 26.8 cm(3) (13.5-55.1) and 36.4 mm (30.0-47.2), respectively. The mean follow-up duration was 113 months (58-167). The tumor control rate and facial nerve function according to the extent of removal were analyzed. The overall tumor control rate was 82%. Perfect tumor control was achieved after NTR and R-STR with adjuvant radiosurgery. However, 11% (1 of 9) of GTR patients and 32% (8 of 25) of R-STR-only and STR patients showed recurrence or regrowth. Overall favorable outcome of facial nerve function (H-B grade 1 or 2) was achieved in 78% of the patients. The facial nerve preservation rate was inversely proportional to the extent of tumor removal. NTR or R-STR with adjuvant radiosurgery might be acceptable therapeutic options for large VS in terms of achieving good tumor control and functional preservation of facial nerve.