Preservation Of Facial Function Research Articles

Management and Outcomes of Facial Nerve Hemangiomas: A Systematic Review of the Literature

Abstract Objectives To conduct a systematic review of facial nerve hemangiomas (FNH), focusing on patient characteristics, management options, and treatment outcomes. Design A systematic review was performed following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, utilizing PubMed, EMBASE, Scopus, and Cochrane databases from inception to December 31, 2022. Setting Literature sourced from various databases providing information on FNH cases. Participants A total of 176 patients with FNH were included in the study, identified from 40 articles meeting inclusion criteria. Main Outcome Measures Patient demographics, lesion characteristics, preoperative symptoms, surgical approaches, and postoperative outcomes, including House-Brackmann (HB) grades. Results Among the 1,682 initially identified articles, 40 were included in the final review. From these, a total of 176 patients (mean age = 42.7 ± 12.8, 51.1% male) were included for analysis. Bivariate analysis showed that patients with longer preoperative symptom duration and facial nerve sacrifice had significantly greater postoperative HB Grades (p < 0.001). Additionally, a strong positive correlation was observed between pre- and postoperative HB Grades (Spearman's rho = 0.649). Multivariable linear regression analysis showed that both facial nerve sacrifice (β = 0.86, 95% confidence interval [CI]: 0.38–1.34; p < 0.001) and greater preoperative HB Grades (β = 0.36, 95% CI: 0.20–0.53; p < 0.001) were associated with significantly greater postoperative HB Grades, but preoperative symptom duration did not persist as a significant predictor of postoperative HB Grades. Conclusions FNHs are rare lesions of the skull base affecting the temporal bone. Our findings highlight the role of preoperative facial nerve function and intraoperative preservation of the facial nerve in predicting postoperative outcomes. Timely resection of lesions that prioritizes facial nerve preservation is critical to achieving optimal patient outcomes.

Subclassification of Koos grade 4 vestibular schwannoma: insights into tumor morphology for predicting postoperative facial nerve function.

Koos grade 4 vestibular schwannoma (KG4VS) is a large tumor that causes brainstem displacement and is generally considered a candidate for surgery. Few studies have examined the relationship between morphological differences in KG4VS other than tumor size and postoperative facial nerve function. The authors have developed a landmark-based subclassification of KG4VS that provides insights into the morphology of this tumor and can predict the risk of facial nerve injury during microsurgery. The aims of this study were to morphologically verify the validity of this subclassification and to clarify the relationship of the position of the center of the vestibular schwannoma within the cerebellopontine angle (CPA) cistern on preoperative MR images to postoperative facial nerve function in patients who underwent microsurgical resection of a vestibular schwannoma. In this paper, the authors classified KG4VSs into two subtypes according to the position of the center of the KG4VS within the CPA cistern relative to the perpendicular bisector of the porus acusticus internus, which was the landmark for the subclassification. KG4VSs with ventral centers to the landmark were classified as type 4V, and those with dorsal centers as type 4D. The clinical impact of this subclassification on short- and long-term postoperative facial nerve function was analyzed. In this study, the authors retrospectively reviewed patients with vestibular schwannoma who were treated surgically via a retrosigmoid approach between January 2010 and March 2020. Of the 107 patients with KG4VS who met the inclusion criteria, 45 (42.1%) were classified as having type 4V (KG4VSs with centers ventral to the perpendicular bisector of the porous acusticus internus) and 62 (57.9%) as having type 4D (those with centers dorsal to the perpendicular bisector). Ventral extension to the perpendicular bisector of the porus acusticus internus was significantly greater in the type 4V group than in the type 4D group (p < 0.001), although there was no significant difference in the maximal ventrodorsal diameter. The rate of preservation of favorable facial nerve function (House-Brackmann grades I and II) was significantly lower in the type 4V group than in the type 4D group in terms of both short-term (46.7% vs 85.5%, p < 0.001) and long-term (82.9% vs 96.7%, p = 0.001) outcomes. Type 4V had a significantly negative impact on short-term (OR 7.67, 95% CI 2.90-20.3; p < 0.001) and long-term (OR 6.05, 95% CI 1.04-35.0; p = 0.045) facial nerve function after surgery when age, tumor size, and presence of a fundal fluid cap were taken into account. The authors have delineated two different morphological subtypes of KG4VS. This subclassification could predict short- and long-term facial nerve function after microsurgical resection of KG4VS via the retrosigmoid approach. The risk of postoperative facial palsy when attempting total resection is greater for type 4V than for type 4D. This classification into types 4V and 4D could help to predict the risk of facial nerve injury and generate more individualized surgical strategies for KG4VSs with better facial nerve outcomes.

Partial superficial parotidectomy for pleomorphic adenoma of the parotid gland: Early post-operative outcomes

IntroductionThere has been historical controversy regarding the extent of resection in the management of pleomorphic adenomas. This study aims to evaluate the extent of surgery and short-term postoperative outcomes of partial superficial parotidectomy (PSP) for the management of pleomorphic adenomas at a tertiary, high-volume center. MethodsA retrospective chart review of patients who underwent PSP was performed. Variables included demographics, pre-operative facial nerve function, operative techniques, postoperative complications/facial nerve function, and recurrence. Results151 adults who underwent PSP for pleomorphic adenoma from January 1st, 2000 to December 31st, 2022 were identified. Median age was 55 (IQR 40–66) years with females representing 74 % of the cohort. Median tumor size at presentation was 1.8 (IQR 1.3–2.3) cm. Baseline facial nerve function was excellent for most patients (House-Brackmann I, 99 %). Most patients underwent a superficial inferior parotidectomy (88 %). Modified Blair incision (70 %) was the most common incision. Intraoperatively, the facial nerve was identified in 149 (99 %) patients. The main trunk was identified in 126 (85 %) patients. No patient had tumor spillage. Only two patients required parotid bed reconstruction. The most common complication was ear numbness (60 %). Postoperatively, 114 patients were House-Brackmann grade I at both preoperative and postoperative assessment, 8 went from grade I to II, and 1 went from grade VI to II (Bell's palsy that resolved to grade II following surgery). Median follow-up was 1(IQR 1–5) month. ConclusionPSP is efficacious in the management of pleomorphic adenomas with preservation of facial nerve function, and minimal post-operative complications. Future study is needed to assess long term recurrence risk.

Delayed facial palsy after resection of vestibular schwannoma: does it influence long-term facial nerve functional outcomes?

OBJECTIVE Delayed facial palsy (DFP) is a common and unique complication after resection of vestibular schwannoma (VS). Few studies have focused on the clinical question of whether patients with DFP can be expected to have the same long-term prognosis in terms of facial nerve function as those without DFP based on their facial nerve function immediately postoperatively. This study aimed to clarify the clinical impact of DFP on the long-term functional status of the facial nerve after VS resection. METHODS The authors retrospectively reviewed patients with sporadic VS who were treated surgically via a retrosigmoid approach between January 2002 and March 2020. DFP was defined as de novo deterioration of facial nerve function by a House-Brackmann (HB) grade ≥ I more than 72 hours postoperatively. The incidence of DFP after VS resection and its impact on long-term facial nerve function were analyzed. RESULTS DFP developed in 38 (14.3%) of 266 patients who met the inclusion criteria. The median latency until DFP onset postoperatively was 8.5 days. When facial nerve function was normal immediately postoperatively, the rate of preservation of favorable facial nerve function (HB grade I or II) at 24 months postoperatively was 100% for all patients regardless of whether they developed DFP. In contrast, when facial nerve dysfunction was present immediately postoperatively, the rate of preservation of favorable facial nerve function at 24 months postoperatively was significantly lower in patients with DFP than in those without DFP (77.8% vs 100% in patients with HB grade II immediately postoperatively, p = 0.001; 50.0% vs 90.3% in those with HB grade III immediately postoperatively, p = 0.042). DFP development had a significantly negative impact on the long-term functional status of the facial nerve postoperatively when age, tumor size, and HB grade immediately postoperatively were taken into account (OR 0.04, 95% CI 0.01–0.20; p &lt; 0.001). CONCLUSIONS DFP can be a minor complication when normal facial nerve function is observed immediately after surgery. However, when facial nerve dysfunction is present immediately after surgery, even if mild, the long-term prognosis for facial nerve function is significantly worse in patients with DFP than in those without DFP.

An Investigation Into Whether the Facial Nerve and Auditory Nerve can be Protected by Removal of the Posterior Wall of the Internal Auditory Canal Under 30° Neuroendoscopy During Vestibular Schwannoma Surgery.

The aim of this study was to evaluate the surgical technique of microresection of vestibular schwannoma by removing the posterior wall of the internal auditory canal (IAC) under neuroelectrophysiological monitoring and 30° neuroendoscopy, with respect to the protection of facial and auditory nerve function. Forty-five cases of microscopic resection of auditory neuromas were performed through a posterior approach to the inferior occipital sigmoid sinus using a 30° neuroendoscope to assist in the removal of the posterior wall of the IAC during surgery. Patients underwent cranial enhancement magnetic resonance imaging examination and functional assessment of the facial and auditory nerves before and after surgery, and clinical data were collected for retrospective analysis. All tumors were removed in 41 patients, and most of the tumors were removed in 4 patients. The facial nerve was anatomically preserved in 43 patients (95.6%), and the percentage of facial nerve function preservation (House-Brackmann grade I-II) was 84.4%. Forty patients (88.9%) had anatomical preservation of the auditory nerve, with a 66.7% functional preservation rate. At 3 to 39 months of follow-up, 45 patients were reviewed with 3.0T-enhanced magnetic resonance imaging, and no tumor recurrence was observed in any of the patients. Microscopic resection of auditory neuroma through the posterior approach of the inferior occipital sigmoid sinus with intraoperative use of 30° neuroendoscopic assistance to abrade the posterior wall of the IAC can eliminate dead space in certain anatomical areas during surgery and minimize surgical damage to the facial and auditory nerves, which is the basis for preservation of facial and auditory nerve function.

Monitoring Cochlear Nerve Action Potential for Hearing Preservation in Medium/Large Vestibular Schwannoma Surgery: Tips and Pitfalls.

The diagnosis of large vestibular schwannomas (VS) with retained useful hearing has become increasingly common. Preservation of facial nerve (FN) function has improved using intraoperative EMG monitoring, hearing preservation remains challenging, with the recent use of cochlear nerve action potential (CNAP) monitoring. This prospective longitudinal series of VS with useful hearing operated on using a retrosigmoid approach included 37 patients with a mean largest extrameatal VS. diameter of 25 ± 8.7 mm (81% of Koos stage 4). CNAP was detected in 51% of patients, while auditory brainstem responses (ABR) were present in 22%. Patients were divided into two groups based on the initial intraoperative CNAP status, whether it was present or absent. FN function was preserved (grade I-II) in 95% of cases at 6 months. Serviceable hearing (class A + B) was preserved in 16% of the cases, while 27% retained hearing with intelligibility (class A-C). Hearing with intelligibility (class A-C) was preserved in 42% of cases when CNAP could be monitored in the early stages of VS resection versus 11% when it was initially absent. Changes in both the approach to the cochlear nerve and VS resection are mandatory in preserving CNAP and improve the rate of hearing preservation.

Intracanalicular vestibular schwannomas: facial and hearing outcomes according to the location of the tumor in relation to the nerves of the internal auditory canal.

The objective was to evaluate whether the position of the nerves within the internal auditory canal (IAC) has any effect on preoperative and postoperative cochlear and facial nerve function in patients with intracanalicular vestibular schwannoma (VS) resected through the retrosigmoid transmeatal approach. Forty-four patients with sporadic intracanalicular VS, from a series of 710 patients with VS who underwent operations from January 1993 to April 2022, were retrospectively reviewed. The pattern of displacement of the cranial nerves and tumor within the IAC was recorded. Tumors were divided into 2 types: type T1A lesions had only anteriorly displaced nerves, and type T1B had posteriorly displaced vestibular nerves and anteriorly displaced facial and cochlear nerves. Differences in surgical outcomes between groups in terms of facial nerve function and hearing preservation were evaluated. Thirty-five cases (79.5%) were T1A tumors and 9 were T1B (20.5%). Gross-total resection and anatomical preservation of the facial and cochlear nerves were achieved in all patients. Postoperatively, all patients with T1A VS maintained normal facial nerve function; however, among T1B VS patients, 6 (67%) retained House-Brackmann grade I, 2 worsened to grade II, and 1 worsened to grade III at 6 months (p = 0.006). The 27 T1A VS patients with serviceable hearing maintained this status, and an additional patient with nonserviceable hearing improved to serviceable hearing; among T1B VS patients, only 2 of the 5 patients with serviceable hearing remained as such, 2 evolved to nonserviceable hearing, and 1 lost hearing after surgery (p = 0.0022). T1B VS patients had a 24-fold risk of facial nerve deterioration (relative risk [RR] 25.2, 95% CI 1.42-448.57, p = 0.028) and a 32-fold risk of hearing deterioration (RR 32.7, 95% CI 1.93-553, p = 0.016) after surgery. In intracanalicular VS, postoperative cochlear and facial nerve function are directly related to the location of the tumor in relation to the nerves, with worse outcomes in cases where the tumor is located between the vestibular and facial-cochlear nerves.

Management of Vestibular Schwannoma

Background Vestibular schwannoma (VS) is considered histologically a benign tumor and is currently preferred over the older term (Acoustic neuroma) as it usually arises from the inferior division of the vestibular nerve and not the acoustic nerve in the cerebellopontine angle. VS were one of the most common intra cranial tumors, comprising 8-10% of tumors in most series. Annual incidence is probably about 1.5 cases per 100,000 population, over the past couple decades this estimate has increased and the typical size at the initial diagnosis has decreased as a result of the advances in the MRI scans &amp; CT scan qualities, (VS) is found to be occurring among middle age groups with no gender prevalence in the fourth or fifth decade. Aim of the Work To evaluate the VS management especially partial resection of large VS followed by gamma knife. Patients and Methods This study is a retrospective prospective study. This study was carried out at Al-Demerdash University hospital, the authority of specialized institutes and teaching hospitals and international medical Centre (Gamma knife department). Time of the study: from March 2019 till March 2021. Results In this study we found that according to the demographic, characteristics &amp; personal history of the study group, it is noted that vestibular shwannoma is common among middle aged group (mean =41 years), with no substantial difference between genders (53% F &amp; 47% M), we found that as regard the clinical picture, most of patients suffered from hearing loss as a complaint (88%) of about 3.5 months duration (median IQR) while all the patients (100%) had a sensory neural sensory loss and verified by PTA, SDT &amp; word discrimination, tinnitus &amp; unsteadiness were found in 70% &amp; 50% respectively. This study has some limitations which are small populations of patients with vestibular schwannoma who generally have short follow-up. We include patients with heterogeneous tumors in regard to size and hearing status. Further studies needed with large populations to establish our results. Conclusion We concluded that considering the good tumor growth control and facial nerve function preservation as well as the possibility of preserving serviceable hearing and the low number of complications, subtotal resection followed by Gamma knife can be the treatment option of choice for large Vestibular schwannoma.

Symptoms: Sudden Sensorineural Hearing Loss and Aural Fullness

Symptoms: Sudden Sensorineural Hearing Loss and Aural Fullness

Outcomes and Prognostic Factors in the Treatment of Intracanalicular Vestibular Schwannomas Using Gamma Knife Stereotactic Radiation.

No gold standard has been developed for the therapy of intracanalicular vestibular schwannomas (IVS). Options for treatment include a conservative approach, microsurgery, or radiosurgery. Although the efficacy of these treatment has been well-documented, little is known about the determinants of outcome in IVSs following radiosurgery. Therefore, we examined the results in relation to age, gender, tumor volume, distance to fundus, microcyst existence, and radiosensitivity in this group. In addition, we investigated possible predictors of facial nerve function and hearing preservation. Ninety-four patients with unilateral IVS were included in the evaluation (52 women and 42 males). The patients were separated into younger and older age groups based on their median age (55 years). The median IVS volume was 138 mm3, microcysts were identified in 16 tumors, and 63 tumors were adjacent to the fundus. The data were analyzed using Statistica software package ver. 13.3. At final follow-up, a statistically significant decrease in tumor volume and no statistically significant decline in hearing were noted, but no differences between age groups were found. The sex had no effect on overall tumor growth control, facial nerve preservation, or hearing preservation. Localization of IVS close to the fundus and the presence of tumor microcysts had no effect on the control of tumor growth, preservation of hearing, and sparing of facial nerve following radiosurgery. Cochlear dose had no influence on hearing preservation. Higher tumor volume was associated with its pseudoprogression during early follow-up and a greater risk of hearing loss. Age, sex, tumor volume, proximity to the fundus, and the existence of a microcyst were not predictive of radiosensitivity nor preservation of facial nerve function and hearing, based on the findings. There was no effect of cochlear dose on hearing. Initial greater tumor volume was associated with an increased probability of tumor pseudoprogression.

527 Multicentric Evaluation of Stereotactic Radiosurgery for Koos Grade IV Vestibular Schwannoma in Young Patients

INTRODUCTION: Koos IV vestibular schwannoma (VS) are preferably treated by surgery. However, SRS can be an alternative for patients with contraindications or who refuse surgery. SRS for Koos IV patient younger than 45 years old has not been previously studied and could be associated with more complications. METHODS: This is a retrospective multicentric study, performed under the International Radiosurgery Research Foundation. Patients 45 years old, treated primarily for a Koos IV VS with single-session SRS, presenting with non life-threatening or incapacitating symptoms, with a follow-up ≥1 years were included. RESULTS: 176 patients with a median age of 36 years (IQR 9) and a median tumor volume of 9.3 cm3 (IQR 4.7) were included. Before SRS, serviceable hearing, facial nerve weakness (House-Brachman &gt;1) and trigeminal neuropathy was present in 51.7%, 8.5%, and 34.1% respectively. The median prescription dose was 12Gy (IQR 0.5). At a median follow-up of 3.1 years (IQR 4.5), tumor stability and regression were 38.9% and 54.3%, respectively. The 5- and 10-year progression-free rate was 90.9% and 86.7%. Early tumor enlargement occurred in 10.9% of cases. The probability of serviceable hearing preservation at 5- and 10-years was 56.8% and 45.2%, respectively. The probability of improvement or preservation of facial nerve function was 95.7% at 5 and 10-years. Adverse radiation effects were noted in 19.9%, 6 of them where managed with surgical resection of the VS. New-onset hydrocephalus occurred in 4.0%. CONCLUSIONS: Single-session SRS in selected Koos IV VS can be an alternative to surgery in a selected group of patients 45 years old. Long-term follow-up is warranted.

Influence of clinical and neurophysiological parameters on the function outcome of the facial nerve after vestibular schwannoma surgery

Introduction: Vestibular schwannomas are benign neoplasms of the nerve seath, and they represent the third most common endocranial tumour, following the meningioma and the pituitary adenomas. The primary symptoms of vestibular schwannomas are hearing loss, tinnitus as well as a balance disorder. The therapy of vestibular schwannoma consists of observation, surgery and radiosurgery. The majority of patients who are good candidates for surgery are already affected by significant hearing impairment, thus one of the primary goals of the surgery is the preservation of facial nerve function. Aim: To analyze the outcome of facial nerve function one-year post-surgery using clinical and neuropsychological parameters. Material and methods: This study analyzed the patient's clinical status on admission along with the neuroradiological characteristics of tumours and the neurophysiological intraoperative parameters and their effect on the facial nerve function in the early postoperative period as well as one year after the surgery using the House–Brackmann scale. Results: A total of 30 patients who underwent surgery from January 1st 2015 to December 31st 2018 at the Clinical Centre of Serbia, Neurosurgery Clinic for vestibular schwannomas were examined. The median age of the patients was 51 years. Hearing loss was present in all patients. Sensitivity drop in the innervation region of n. trigeminus was present in 7 (23.3%) patients, as was tinnitus. Cerebellar symptomatology (76%) was present in the highest percentage of patients. Conclusion: We can conclude that the most important aspects of the facial nerve function are the preoperative state of the facial nerve and the electrophysiological parameters. Although the radical procedure of surgery led to an immediate postoperative outcome, it was not significant for the ultimate outcome of treatment. Thus, radical surgery may be considered to carry the same risk of definitive impairment of the facial nerve function, just like a combination treatment with subtotal resection and stereotaxic radiosurgery.

A Study on the Role of Intraoperative Corticobulbar Motor Evoked Potentials for Improving Safety of Cerebellopontine Angle Surgery in Elderly Patients

Preservation of facial nerve function (FNF) during neurosurgery for cerebellopontine angle (CPA) tumors is paramount in elderly patients. Corticobulbar facial motor evoked potentials (FMEPs) allow assessment intraoperatively of the functional integrity of facial motor pathways, thus improving safety. We aimed to evaluate the significance of intraoperative FMEPs in patients 65 years and older. A retrospective cohort of 35 patients undergoing CPA tumors resection was reported; outcomes of patients aged 65-69 years vs. ≥70 years were compared. FMEPs were registered both from upper and lower face muscles, and amplitude ratios (minimum-to-baseline, MBR; final-to-baseline, FBR; and recovery value, FBR minus MBR) were calculated. Overall, 78.8% of patients had a good late (at 1 year) FNF, with no differences between age groups. In patients aged ≥70 years, MBR significantly correlated with late FNF. At receiver operating characteristics (ROC) analysis, in patients aged 65-69 years, FBR (with 50% cut-off value) could reliably predict late FNF. By contrast, in patients aged ≥70 years, the most accurate predictor of late FNF was MBR, with 12.5% cut-off. Thus, FMEPs are a valuable tool for improving safety in CPA surgery in elderly patients as well. Considering literature data, we noticed higher cut-off values for FBR and a role for MBR, which suggests an increased vulnerability of facial nerves in elderly patients compared to younger ones.

Vestibular Schwannoma Surgery with Endoscope-Assisted Retrolabyrinthine Approach under Modified Reinforced Continuous Intraoperative Monitoring for Hearing Preservation: Experience of 33 Cases in a Single Center.

Surgery for vestibular schwannoma includes various techniques such as the middle cranial fossa, suboccipital, translabyrinthine, and retrolabyrinthine approaches. The retrolabyrinthine approach does not impair the labyrinth and allows postoperative hearing preservation. Previously, we reported an endoscope-assisted retrolabyrinthine approach under reinforced continuous intraoperative monitoring for preservation of hearing and facial nerve function. However, the hearing preservation rate was relatively low in patients with long-wave V latency in the auditory brainstem response or poor otoacoustic emission response under this approach. Thus, the hearing preservation rate in such patients remains to be improved. To overcome this limitation, we modified the previous approach. In 26 of the 33 consecutive cases (79%) over the last three years, preservation of hearing equivalent to that before surgery or improved hearing was achieved. Postoperative deafness was observed in only two of the 33 cases (6%). According to previous reports, the rate of hearing preservation using the retrolabyrinthine approach is approximately 30-50%. Therefore, we have achieved a higher hearing preservation rate than that previously reported using the endoscopy-assisted retrolabyrinthine approach under reinforced continuous intraoperative monitoring. These improvements in our department are considered to be helpful for hearing preservation.

Management of Vestibular Schwannoma with Normal Hearing

Introduction: This work aimed to study the management of vestibular schwannoma (VS) patients with normal hearing (NH). Methods: A retrospective study was undertaken in a Quaternary referral center for skull base pathologies. Among 4,000 VS patients 162 met our strict audiological criteria for NH. These patients were divided into 2 management groups, wait and scan (W&S) (45/162, 25%) and operated patients (123/162, 75%), and 6 patients were included in both groups. Results: Our management strategy achieved the goals for treatment of VS. First goal, all tumors were completely removed except for 2 intentional residuals. Second goal, facial nerve (FN) function preservation (House Brackmann I, II, and III) was 95.9%. Third goal, possible hearing preservation (HP) attempts occurred in (50/122) (40.9%) with an HP rate in 44% of the patients. Additionally, there were only 2 cases of postoperative complications with no CSF leakage. The prospect of HP in NH patients did not differ with respect to tumor size. However, patients with normal preoperative ABR seemed to have better chances of HP and good FN function and vice versa. HP rate was superior for the MCFA as opposed to the RS + RLA. W&S group demonstrated hearing stability in 88.9% of the patients and FN function stability of HB I in 100% of the patients. Conclusions: Surgical resection is a reasonable and definitive management option for VS with NH. Nevertheless, choosing to manage cases with observation remains an appropriate management option for NH patients. ABR might be considered as an adjuvant tool indicating better prognosis for HP.

Presence of a fundal fluid cap on preoperative magnetic resonance imaging may predict long-term facial nerve function after resection of vestibular schwannoma via the retrosigmoid approach.

Preservation of neurological function is a priority when performing a resection of a vestibular schwannoma (VS). Few studies have examined the radiographic value of a fundal fluid cap-i.e., cerebrospinal fluid in the lateral end of a VS within the internal auditory canal-for prediction of postoperative neurological function. The aim of this study was to clarify whether the presence of a fundal fluid cap on preoperative magnetic resonance images has a clinical impact on facial nerve function after resection of VSs. The presence of a fundal fluid cap and its prognostic impact on long-term postoperative facial nerve function were analyzed. A fundal fluid cap was present in 102 of 143 patients who underwent resection of sporadic VSs via the retrosigmoid approach. Facial nerve function was acceptable (House-Brackmann grade I-II) immediately after surgery in 82 (80.4%) patients with a fundal fluid cap and in 26 (63.4%) of those without this sign. The preservation rate of facial nerve function increased in a time-dependent manner after surgery in patients with a fundal fluid cap but plateaued by 3 months postoperatively in those without a fundal fluid cap; the difference was statistically significant at 12 months (96.1% vs 82.9%, p = 0.013) and 24 months (97.1% vs 82.9%, p = 0.006) after surgery. The presence of a fundal fluid cap had a significantly positive effect on long-term facial nerve function at 24 months after surgery when tumor size and intraoperative neuromonitoring response were taken into account (OR 5.55, 95% CI 1.12-27.5, p = 0.034). Neuromonitoring-guided microsurgery for total resection of VSs is more likely to be successful in terms of preservation of facial nerve function if a fundal fluid cap is present. This preoperative radiographic sign could be helpful when counseling patients and deciding the treatment strategy.

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.

Application of Subperineural Resection Technique in Vestibular Schwannomas: Surgical Efficacy and Outcomes in 124 patients.

ObjectiveWe aimed to explore the application and prospects of the subperineural resection technique for tumor separation and removal under the perineurium during surgery for vestibular schwannomas (VSs).MethodsThis study retrospectively analyzed 124 patients with VSs who underwent surgery via a retrosigmoid approach from July 2015 to October 2020 in the Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University. The data will be discussed with regard to the following aspects: clinical features, surgical strategies, tumor resection extent, facial–acoustic function preservation, and postoperative complications.ResultsGross total resection (GTR) of the tumor was achieved in 104 patients, with a GTR rate of 83.9%, and subtotal resection (STR) of the tumor was achieved in 20 patients. There was no significant difference in facial and acoustic nerve functional preservation between GTR and STR, as well as in tumor resection between solid and cystic tumors. The retention rate reached 97.6% in terms of complete anatomical facial nerve preservation. Facial nerve function was assessed using the House–Brackmann (HB) grading score. Consequently, HB grades of I–II, III–IV, and V–VI were determined for 96 (77.4%), 25 (20.2%), and 3 (2.4%) cases, respectively, 1 week postoperatively and accounted for 110 cases (88.7%), 13 cases (10.5%), and 1 case (0.8%), respectively, at 6 months. Fifteen of 35 (42.9%) patients with serviceable hearing before the operation still had serviceable hearing at 6 months postoperatively. There were 5 cases of cerebellar or brainstem bleeding after the operation, and one patient died. Multivariate logistic regression analysis showed that older age (≥60 years, p = 0.011), large tumor (>3 cm, p = 0.004), and cystic tumor (p = 0.046) were independent risk factors associated with the extent of adhesion between the tumor and the brainstem and facial–acoustic nerve.ConclusionWe successfully applied the subperineural resection technique to a large series of patients with VSs and achieved satisfactory results. Accurate identification of the perineurium and subperineural resection of the tumor can effectively reduce the disturbance of the facial–acoustic nerve during the operation and provide an intuitive basis for judging the tumor boundary. The subperineural resection technique may be conducive to improving the rate of total tumor resection and facial–acoustic nerve functional preservation in the surgical treatment of VSs.

Preservation of facial nerve function after resection of vestibular schwannoma

The objective of this study was to provide a comprehensive assessment of reported outcomes for facial nerve preservation after vestibular schwannoma surgery. Most data regarding facial nerve function in patients undergoing microsurgical resection of vestibular schwannomas predominantly include series performed at a single institution. In an effort to minimise individual surgeon or institutional bias, we performed an analysis of the published literature on facial nerve outcomes following microsurgical resection of vestibular schwannomas. Materials and methods. We identified a total of 296 studies involving over 25,000 patients that included outcome data for facial nerve function of vestibular schwannoma patients treated surgically. Data regarding surgical approach, tumour size, patient age, and use of intra-operative monitoring were extracted and correlated with facial nerve function after surgery. Patients with preoperative facial nerve dysfunction (House-Brackmann score III or higher) were excluded and ‘facial nerve preservation’ was defined as grade I or II House-Brackmann function at last follow-up visit. Results. A total of 79 articles reporting on 11,873 patients met our inclusion criteria contributing to our analysis. Patients treated with the middle cranial fossa approach had a trend towards higher overall facial nerve preservation rate (85 %), compared to the translabyrinthine approach (81 %, p = 0.07), and did statistically better than the retrosigmoid approach (78 %, p &lt; 0.0001). Patients with an average tumour size &lt; 20 mm had significantly improved facial nerve preservation rates, compared to larger tumours (90 % vs. 67 %, p &lt; 0.0001). Patients under 65 years of age had a lower facial nerve preservation rate (71 % vs. 84 %, p &lt; 0.001). Finally, the use of intra-operative monitoring improved the facial nerve preservation rate (76 % vs. 71 %, p &lt; 0.001). Conclusion. Factors that appear to be associated with facial nerve preservation after microsurgical resection of a vestibular schwannoma include tumour size &lt;20 mm, use of the middle fossa approach and use of neuromonitoring during surgery. These data provide a summary assessment of the published literature regarding facial nerve preservation after microsurgical resection of vestibular schwannoma.

Clinical Benefits of Facial Nerve Monitoring during Cerebellopontine Angle Surgery

Background: The surgery of cerebellopontine angle tumours has remarkably progressed over the last 2 decades due to improved microsurgical techniques. The primary operative goals are microscopic total removal of the tumour while securing the adjacent cranial nerves. Facial Nerve plays a critical role in facial muscles function and one’s cosmetic appearance, and its weakness can have profound implications on a patient’s quality of life. Aim of the Study: To assess the impact of monitoring techniques on the preservation of facial nerve function during cerebellopontine angle tumours surgery. Patients and Methods: This is a prospective study. This study was conducted on 30 cases (2 groups, each had 15 patients) with CPA lesions that had undergone surgical excision of these lesions performed by retrosigmoid approach (Group A: the patients were operated under continuous intraoperative facial nerve monitoring (IOFNM) and Group B: the patients were operated without IOFNM). They were operated upon in neurosurgery departments at Al-Azhar university hospitals between August 2019 and August 2021. Results: This study showed that excellent facial nerve function (HB Grade I and II) was higher in group A than group B, immediately and at 6-month post op (80% and 93% VS 53.3% and 66.7%). Intermediate (HB Grade III and VI) and Poor (HB Grade V and VI) facial nerve function was higher in group B than group A; both immediately and 6-month postop (46.7% and 33.3% VS 20% and 6.6%). However, no statistically significant P-Value between both groups. Conclusion: We concluded that IOFNM can help, but cannot guarantee, the preservation of facial nerve. Furthermore, it is merely a technical adjunct and does not replace surgical skills, knowledge of anatomy and experience.