Audiologic Outcomes After Vestibulotomy in Patients With Congenital Absence of the Oval Window.

OBJECTIVE: To examine the clinical features and surgical outcomes in patients with congenital absence of the oval window (CAOW), and to investigate the potential factors that affect audiologic results. STUDY DESIGN: A retrospective chart review. SETTING: A tertiary academic center. PATIENTS AND INTERVENTION: A total of 17 ears among 16 patients were confirmed to have CAOW. Among them, 13 ears underwent vestibulotomy for hearing reconstruction. Clinical parameters associated with the hearing outcomes were analyzed. MAIN OUTCOME MEASURES: A mean air-bone gap (ABG) after 6-month and long-term follow-up was compared with preoperative measurements. RESULTS: Intraoperative findings showed that anomalies of the malleus or incus were observed in 11 ears (64.7%), stapes anomalies were present in all ears (100%), and facial nerve anomalies were present in 10 ears (58.8%). Because of unfavorable facial nerve anomalies, hearing reconstruction was aborted in four cases (23.5%). In the hearing reconstruction group, the mean ABG at 6 months postoperation was significantly reduced after compared with the preoperative value (44.0 ± 8.4 dB versus 58.8 ± 9.1 dB, p = 0.006). After dividing ears into a success subgroup (ABG ≤ 30 dB, seven ears) and non-success subgroup (ABG > 30 dB, six ears), the use of a drill during vestibulotomy was significantly related to a poor hearing outcome (100% versus 16.7%, p = 0.015). The long-term follow-up result (mean, 60 mo) revealed no deterioration compared with the 6-month postoperative result. Five ears (29.4%) underwent revision surgery, and three of them showed ABG improvements. No serious complications were reported. CONCLUSION: Vestibulotomy is an effective and safe option for hearing restoration in patients with CAOW, particularly when the use of a drill is not required. The long-term audiologic outcome is also reliable.

Fenestration of the facial nerve by the stylomastoid artery.

BACKGROUND: Anatomic landmarks such as the tympanomastoid suture line, posterior belly of the digastric muscle, tragal pointer, and styloid process can assist the parotid surgeon in identifying and preserving the facial nerve. Vascular structures such as the posterior auricular artery and its branch, the stylomastoid artery, lay in close proximity to the facial nerve and have been proposed as landmarks for the identification of the facial nerve. In this case report, we describe an anatomic variation in which the stylomastoid artery has fenestrated the main trunk of the facial nerve, dividing it in two. METHODS: Two patients underwent parotidectomy (one for a pleomorphic adenoma, the second for a parotid cyst) through a standard anterograde approach with identification of the usual facial nerve landmarks. RESULTS: The appearance of the main trunk of the facial nerve was unusual in both patients due to its being fenestrated by the stylomastoid artery. The stylomastoid artery was divided, and the remainder of the facial nerve dissection was performed uneventfully with subsequent resection of the parotid mass in both patients. CONCLUSIONS: In rare instances, the stylomastoid artery can penetrate through the common trunk of the facial nerve. This is an important anatomic variant for the parotid surgeon to be aware of, as it can increase the difficulty of facial nerve dissection.

[Analysis of the effect of different facial nerve managements applied to tumor resection in the jugular foramen region].

Objective:To summarize the results of different facial nerve management modalities applied to tumor resection in the jugular foramen region. Methods:The clinical data of 54 patients with tumors in the jugular foramen region who underwent surgery from January 2015 to March 2023 were retrospectively analyzed: 18 males and 36 females; Age ranges from 21 to 67 years, with an average age of 44.4 years; and median follow-up time: 12 months. The House-Brackmann（HB） grading system was applied to assess the patients' facial nerve function before surgery, 1-2 weeks after surgery and at the final follow-up （HBⅠ-Ⅱ grade for good function）: 42 cases with preoperative HB grades Ⅰ-Ⅱ; partial facial nerve transposition（9 cases）, complete facial nerve transposition（28 cases）, and facial nerve excision and re-construction（17 cases） were used, respectively（stage Ⅰor Ⅱ）. Relevant factors affecting postoperative facial nerve function were analyzed. Results:Postoperative pathology confirmed 39 cases of paraganglioma, 9 cases of nerve sheath tumor, 3 cases of meningioma, and 1 case each of fibromucinous sarcoma, chondrosarcoma, and intravascular myofibroma. Facial nerve function after partial facial nerve transposition was HB grade Ⅰ-Ⅱ in 89%（8/9）; after complete facial nerve transposition was HB grade Ⅰ-Ⅱ in 86%（24/28） in 28 cases; after facial nerve severance and reconstruction was HB grade Ⅰ-Ⅱ in 2/7（Stage Ⅰ） and 0/3（Stage Ⅱ）, respectively. Tumor size and surgical approach were correlated with postoperative facial nerve function in patients with facial nerve transposition（P<0.05）. There was no statistically significant difference in facial nerve function after complete and partial facial nerve transposition（P>0.05）. Conclusion:Intraoperative stretching of the facial nerve may be an important factor affecting facial nerve function during surgical treatment of tumors in the jugular venous foramen region; for patients with facial nerve dissection, facial nerve reconstruction should be adopted according to the situation, aiming at the recovery of facial nerve function.

[Clinical analysis of transcranial facial nerve bridging with interpositional graft for the treatment of facial nerve injury].

Objective:To retrospectively analyze the effectiveness of transcranial facial nerve bridging in the treatment of facial nerve dysfunction. Methods:A retrospective analysis was conducted on 27 patients with facial nerve dysfunction who underwent transcranial facial nerve bridging at the Eye, Ear, Nose, and Throat Hospital affiliated with Fudan University from 2017 to 2022. The main collected data includes the patient's age, gender, primary lesion, damaged location, interval from facial paralysis to surgery, and preoperative and postoperative House-Brackmann（HB） scale for facial nerve function. Statistical comparisons were made between the average HB level of patients before and after surgery. Results:A total of 27 patients included 17 males and 10 females. The average age of patients during surgery is（42.50±3.38） years old. Primary lateral skull base diseases include trauma（n=3）, tumors（n=22）, and infections（n=2）. The duration of facial paralysis varies from 6 months to 5 years. Statistics analysis has found that the average postoperative HB score of patients who underwent transcranial facial nerve bridging was significantly lower at（3.750 ± 0.183） compared to preoperative（4.875±0.168）. The proportion of patients with good facial nerve function increased significantly from 7.4% before surgery to 42.9% after surgery. Conclusion:Transcranial facial nerve bridging surgery with interpositional graft has a significant effect on improving facial nerve function in patients with facial nerve injury. Further research is still needed to evaluate the long-term effectiveness of this surgery, to determine the optimal patient selection criteria and postoperative rehabilitation strategies.

[The assessment of facial nerve function].

The assessment of facial nerve function plays a crucial role in the diagnosis and treatment of facial nerve disorders.The assessment system for facial nerve function is primarily categorized into subjective and objective systems.While the subjective assessment system is relatively simple, it lacks accuracy as it can be influenced by the subjectivity of evaluator.Whereas, the objective system offers higher precision and stability, providing more quantitative information. In recent years, benefited with advancements in computer vision and artificial intelligence,we have witnessed increasingly accurate,stable and intelligent facial nerve assessment systems gradually implemented in clinical practice.When selecting a specific facial nerve assessment system,factors such as clinical scenarios,assessment objectives,patient characteristics should be considered.

[Postoperative effect analysis of different surgical techniques used in facial nerve reconstruction].

Objective:To investigate the factors and efficacy of different surgical techniques used in facial nerve（FN） reconstruction. Methods:A retrospective analysis was conducted on 24 patients who underwent facial nerve reconstruction surgery in our department from January 2016 to January 2021. The duration of total facial nerve paralysis was less than 18 months. The study included 5 surgical techniques, including 6 cases of FN anastomosis（Group A）, 5 cases of FN grafting（sural nerve or great auricular nerve）（Group B）, 5 cases of side-to-end facial-hypoglossal nerve anastomosis（Group C）, 4 cases of side-to-end FN grafting（sural nerve or great auricular nerve） hypoglossal nerve anastomosis（Group D）, and 4 cases of dual nerve reanimation（Group E）. The postoperative follow-up period was ≥1 year. Results:The HB-Ⅲ level of FN function at 1 year after surgery was 83.3%（5/6） in group A, 60.0%（3/5） in group B, 40.0%（2/5） in group C, 25.0%（1/4） in group D, and 50.0%（2/4） in group E. In patients without multiple FN repair, the incidence of synkinesis was 15.0%（3/20）, while no cases of synkinesis were observed in patients with dual nerve reanimation. The patients who underwent hypoglossal-facial side-to-end anastomosis showed no hypoglossal nerve dysfunction. Conclusion:Different FN repair techniques result in varying postoperative FN function recovery, as personalized repair should be managed. Among the various techniques, FN end-to-end anastomosis after FN transposition is recommended as to reduce the number of anastomotic stoma, while hypoglossal-facial side-to-end anastomosis is advocated as to prevent postoperative hypoglossal nerve dysfunction. Additionally, dual nerve repair can effectively improve smile symmetry and reduce synkinesis, which enhances patients' quality.

[Effect analysis of facial nerve decompression surgery in the treatment of Bell's palsy and Hunt syndrome].

Objective:To summarize and analyze the effect of facial nerve decompression surgery for the treatment of Bell's palsy and Hunt syndrome. Methods:The clinical data of 65 patients with facial nerve palsy who underwent facial nerve decompression in our center from October 2015 to October 2022 were retrospectively analyzed, including 54 patients with Bell's palsy and 11 patients with Hunter syndrome. The degree of facial paralysis（HB grade） was evaluated before surgery, and ENoG, pure tone audiometry, temporal bone CT and other examinations were completed. All patients had facial palsy with HB grade V or above after conservative treatment for at least 1 month, and ENoG decreased by more than 90%. All patients underwent facial nerve decompression surgery through the transmastoid approach within 3 months after onset of symptoms. The recovery effect of facial nerve function after surgery in patients with Bell's palsy and Hunter syndrome was summarized and analyzed. In addition, 15 cases in group A（operated within 30-60 days after onset） and 50 cases in group B（operated within 61-90 days after onset） were grouped according to the course of the disease（the interval between onset of symptoms and surgery） to explore the effect of surgical timing on postoperative effect. Results:There was no significant difference between the two groups of patients with Chi-square test（P=0.54） in 42 patients（77.8%, 42/54） with Bell's palsy and 7 patients（63.6%, 7/11） in patients with Hunter syndrome who recovered to grade Ⅰ-Ⅱ. According to the course of the disease, 10 cases（66.7%, 10/15） in group A recovered to grade Ⅰ-Ⅱ after surgery. In group B, 39 patients（78.0%, 39/50） recovered to grade Ⅰ-Ⅱ after surgery, and there was no statistically significant difference between the two groups by Chi-square test（P=0.58）. Conclusion:Patients with Bell's palsy and Hunter syndrome can achieve good results after facial nerve decompression within 3 months of onset, and there is no significant difference in the surgical effect between the two types of patients.

[Clinical characteristics and prognosis of two anastomosis techniques in the treatment of facial nerve defects].

Objective:To investigate the characteristics and prognosis of two anastomosis techniques in repairing facial nerve defects. Methods:A retrospective analysis was conducted on 30 patients who underwent facial nerve anastomosis（direct or rerouting） for facial nerve defects in our department from January 2012 to December 2021. Among them, 21 were male and 9 were female, with an average age of（37.53±11.33） years, all with unilateral onset. Preoperative House-Brackmann（H-B） facial nerve function grades were Ⅳ in 2 cases, Ⅴ in 9 cases, and Ⅵin 19 cases. The duration of facial paralysis before surgery was within 6 months in 21 cases, 6-12 months in 6 cases, and over 1 year in 3 cases. The causes of facial paralysis included 14 cases of cholesteatoma, 6 cases of facial neurioma, 6 cases of trauma, and 4 cases of middle ear surgery injury. Surgical approaches included 9 cases of the middle cranial fossa approach, 8 cases of labyrinthine-otic approach, 7 cases of mastoid-epitympanum approach, and 6 cases of retroauricular lateral neck approach. Results:All patients were followed up for more than 2 years. The direct anastomosis was performed in 10 cases: 6 cases with defects located in the extratemporal segment and 4 cases in the tympanic segment. Rerouting anastomosis was performed in 20 cases: 11 cases with defects located in the labyrinthine-geniculate ganglion, 4 cases from the internal auditory canal to the geniculate ganglion, 3 cases in the internal auditory canal, and 2 cases in the horizontal-pyramid segment. Postoperative H-B facial nerve grades were Ⅱ in 2 cases, Ⅲ in 20 cases, and Ⅳ in 8 cases, with 73.3%（22/30） of patients achieving H-B grade Ⅲ or better. Conclusion:Both direct and rerouting anastomosis techniques can effectively repair facial nerve defects, with no significant difference in efficacy between the two techniques. Most patients can achieve H-B grade Ⅲ or better facial nerve function recovery. Preoperative facial nerve function and duration of facial paralysis are the main prognostic factors affecting the outcome of facial nerve anastomosis.

[Facial nerve protection in surgery for rare tumors of the internal auditory canal].

Objective:To explore strategies for preserving facial nerve function during surgeries for rare tumors of the internal auditory canal. Methods:A total of 235 cases of internal auditory canal tumors treated between 2010 and 2023 were included, encompassing vestibular schwannomas, cavernous hemangiomas, meningiomas, and other rare tumors. Various data, including clinical presentations, imaging classifications, and treatment processes, were meticulously analyzed to delineate the characteristics of rare tumors and assess pre-and postoperative facial nerve function. Results:Among all internal auditory canal tumors, vestibular schwannomas accounted for 91.9%. In rare tumors, facial nerve schwannomas constituted 5.3%, cavernous hemangiomas 26.3%, meningiomas 15.8%, and arterial aneurysms 10.5%. Significantly, patients with cavernous hemangiomas displayed pronounced invasion of the facial nerve by the tumor, in contrast to other tumor types where clear boundaries with the facial nerve were maintained. During surgery, individualized approaches and strategies for facial nerve protection were implemented for different tumor types, involving intraoperative dissection, tumor excision, and facial nerve reconstruction. Conclusion:Preservation of the facial nerve is crucial in the surgical management of rare tumors of the internal auditory canal. Accurate preoperative diagnosis, appropriate timing of surgery, selective surgical approaches, and meticulous intraoperative techniques can maximize the protection of facial nerve function. Personalized treatment plans and strategies for facial nerve functional reconstruction are anticipated to enhance surgical success rates, reduce the risk of postoperative facial nerve dysfunction, and ultimately improve the quality of life for patients.

[Diagnosis and treatment of 68 cases of traumatic facial nerve paralysis].

Objective:To summarize the clinical characteristics and therapeutic effect of traumatic facial nerve palsy. Methods:Sixty-eight cases of traumatic facial nerve palsy were retrospectively analyzed from January 2015 to May 2023. Results:The median course of disease was 33 days. The facial nerve function of the patients was grade HB-Ⅱin 2 cases, grade HB-Ⅲ in 4 cases, grade HB-Ⅳin 16 cases, grade HB-Ⅴ in 37 cases（38 ears）, and grade HB-Ⅵ in 9 cases. 42 cases occurred immediately after injury and 26 cases were delayed. CT examination of temporal bone revealed longitudinal fractures in 51 cases（52 ears） , transverse fractures in 6 cases and mixed fractures in 4 cases. No definite temporal bone fracture was found in the remaining 7 cases. The segments of facial nerve injury in 49 cases（50 ears） were geniculate ganglion and adjacent, in 7 cases were vertical segment, in 7 cases were horizontal segment, in 2 cases were horizontal segment and vertical segment; and the other 3 cases could not be evaluated. Conservative treatment with glucocorticoids was used in 23 ears and surgery was used in 46 ears. Patients were followed up 6-24 months after treatment, including 20 cases of grade HB-Ⅰ, 19 cases of grade HB-Ⅱ, 23 cases（24 ears） of grade HB-Ⅲ, 4 cases of grade HB-Ⅳ, and 1 case of grade HB-Ⅴ.One patient was lost to follow-up. After treatment, the facial nerve function of patients was significantly improved（P<0.05）, and there were significant differences between conservative treatment group and surgical treatment group in the course of facial nerve palsy, the ratio of facial palsy immediately after injury, the nerve function before treatment and the nerve function after treatment（P<0.05）. There were no significant differences in age, sex, hearing condition, temporal bone fracture, facial nerve injury segment and rate of favorable neurologic outcomes（P>0.05）. The comparison of patients with neurodegeneration rate>90% and ≤90% showed that the facial nerve function of patients with neurodegeneration rate>90% before treatment was significantly worse（P<0.05）, but there was no significant difference between the facial nerve function after treatment（P>0.05）. There was no significant difference in facial nerve function between middle fossa approach group and mastoid approach group（P>0.05）. Conclusion:Patients with traumatic facial nerve palsy should be evaluated individually. Patients with mild facial nerve palsy, low neurodegeneration rate and short course of disease can be treated conservatively and followed up closely. Patients with severe facial nerve palsy, high neurodegeneration rate and more than 6 weeks of disease can be actively considered surgery. Good prognosis can be obtained by correct evaluation and treatment.

[Analysis of clinical manifestations and imaging features of facial nerve schwannomas].

Objective:To explore the clinical manifestations and imaging characteristics, and to clarify the imaging value in the diagnosis of facial nerve schwannomas. Methods:Retrospectively analyze the data of 23 patients with facial nerve schwannomas confirmed by surgery and pathology in the Department of Otorhinolaryngology of the First Affiliated Hospital of the Air Force Military Medical University from September 2020 to September 2022, including 8 males and 15 females, aged 18-66 years old. Summarize and analyze their clinical symptoms, specialized examinations, and imaging findings. Results:The clinical manifestations were facial nerve paralysis in 15 cases（2 cases of HB Ⅳ, 6 cases of HB Ⅴ, 7 cases of HB Ⅵ）, hearing loss in 14 cases（5 cases of conductive deafness, 2 cases of mixed deafness, and 7 cases of severe sensorineural hearing loss）, 8 cases tinnitus, 7 cases ear pain, 4 cases dizziness, 4 cases headache, 2 cases ear pus, and parotid gland tumors in 6 cases presenting as local masses. Endoscopic examination revealed 8 cases of external ear canal tumors and 3 cases of intratympanic tumors. Combining temporal bone HRCT, MRI enhanced scanning, and CPR imaging techniques, 1 case involved the internal auditory canal segment, 2 cases in the tympanic segment, 6 cases in the parotid gland area. A total of 14 cases involved two or more segments of the internal auditory canal segment, the labyrinthine segment, geniculate ganglion, the tympanic segment, and the mastoid segment. When the tumors were large, adjacent structures were involved. It was found that 8 cases invaded the external auditory canal and tympanic cavity, ossicles were displaced or bony destruction; 3 cases invaded the jugular foramen area, and 1 case grew to the middle cranial fossa region with temporal lobe brain parenchymal compression. Conclusion:The clinical manifestations of facial nerve schwannomas are diverse. The combination of various imaging techniques will be conducive to topical and qualitative diagnosis and provide an important basis for treatment strategies.

[Cochlear implantation through retro-facial approach with congenital microtia malformation with facial nerve deformity: a case report].

The difficulty of cochlear implantation in patients with congenital microtia is usually increased due to the vague anatomical marks and facial nerve malformation. The common types of facial nerve malformation include facial nerve bony cover loss, aberrant position, and bifurcation malformation. Bifurcation malformation may obscure the oval window, press against stapes, and bifurcate in the vestibular window while obscuring the round window. It is important to correctly identify the facial nerve and choose a reasonable surgical approach to avoid postoperative complications. This article describes a case of profound sensorineural hearing loss due to facial nerve malformation in our institution. The patient underwent cochlear implantation through the retro-facial approach. There was no facial nerve injury or dysfunction symptoms such as facial paralysis and hemifacial spasm 2 years after the operation, and the cochlear implant works well. The score of the categories of the auditory performance（CAP） questionnaire was 7, and the score of the speech intelligibility rating（SIR） questionnaire was 4. When the round window cannot be exposed through the facial recess approach during surgery, the retro-facial approach is a feasible method. To avoid facial nerve injury, a thin-section CT of the temporal bone should be performed before the middle and inner ear surgery for patients with facial nerve malformation, and the intraoperative facial nerve monitor should be used to clarify the course of the facial nerve to avoid injury.

Refining the predictive value of preoperative apparent diffusion coefficient (ADC) by whole-tumor analysis for facial nerve outcomes in vestibular schwannomas.

BACKGROUND: Apparent diffusion coefficient (ADC) in MRI has been shown to correlate with postoperative House-Brackmann (HB) scores in patients with vestibular schwannoma despite limited methodology. To rectify limitations of single region of interest (ROI) sampling, we hypothesize that whole-tumor ADC histogram analysis will refine the predictive value of this preoperative biomarker related to postoperative facial nerve function. METHODS: Of 155 patients who underwent resection of vestibular schwannoma (2014-2020), 125 patients were included with requisite clinical and radiographic data. After volumetric analysis and whole-tumor ADC histogram, regression tree analysis identified ADC cutoff for significant differences in HB grade. Outcomes were extent of resection, facial nerve function, hospital length of stay (LOS), and complications. RESULTS: Regression tree analysis defined three quantitative ADC groups (× 10-6 mm2/s) as high (> 2248.77; HB 1.7), mid (1468.44-2248.77; HB 3.1), and low (< 1468.44; HB 2.3) range (p 0.04). The mid-range ADC group had significantly worse postoperative HB scores and longer hospital LOS. Large tumor volume was independently predictive of lower rates of gross total resection (p <0.0001), higher postoperative HB score (p 0.002), higher rate of complications (p 0.04), and longer LOS (p 0.003). CONCLUSIONS: Whole-tumor histogram yielded a robust regression tree analysis that defined three ADC groups with significantly different facial nerve outcomes. This likely reflects tumor heterogeneity better than solid-tumor ROI sampling. Whole-tumor ADC warrants further study as a useful radiographic biomarker in patients with vestibular schwannoma who are considering surgical resection.

GFP-labeled Schwann cell-like cells derived from hair follicle epidermal neural crest stem cells promote the acellular nerve allografts to repair facial nerve defects in rats.

BACKGROUND: Acellular nerve allografts (ANAs) have been successfully applied to bridge facial nerve defects, and transplantation of stem cells may enhance the regenerative results. Up to now, application of hair follicle epidermal neural crest stem cell-derived Schwann cell-like cells (EPI-NCSC-SCLCs) combined with ANAs for bridging facial nerve defects has not been reported. METHODS: The effect of ANAs laden with green fluorescent protein (GFP)-labeled EPI-NCSC-SCLCs (ANA + cells) on bridging rat facial nerve trunk defects (5-mm-long) was detected by functional and morphological examination, as compared with autografts and ANAs, respectively. RESULTS: (1) EPI-NCSC-SCLCs had good compatibility with ANAs in vitro. (2) In the ANA + cells group, the GFP signals were observed by in vivo imaging system for small animals within 8 weeks, and GFP-labeled EPI-NCSC-SCLCs were detected in the tissue slices at 16 weeks postoperatively. (3) The facial symmetry at rest after surgery in the ANA + cells group was better than that in the ANA group (p < 0.05), and similar to that in the autograft group (p > 0.05). The initial recovery time of vibrissal and eyelid movement in the ANA group was 2 weeks later than that in the other two groups. (4) The myelinated fibers, myelin sheath thickness and diameter of the axons of the buccal branches in the ANA group were significantly worse than those in the other two groups (P < 0.05), and the results in the ANA + cells group were similar to those in the autograft group (p > 0.05). CONCLUSIONS: EPI-NCSC-SCLCs could promote functional and morphological recovery of rat facial nerve defects, and GFP labeling could track the transplanted EPI-NCSC-SCLCs in vivo for a certain period of time. These may provide a novel choice for clinical treatment of peripheral nerve defects.

Dengue-associated longitudinally extensive transverse myelitis.

We diagnosed a patient with dengue fever who developed acute onset of sensorimotor quadriparesis with bladder involvement, and facial nerve involvement. Despite initial negative results in routine investigations and cerebrospinal fluid analysis, spinal MRI confirmed longitudinally extensive transverse myelitis. The aetiological workup was negative, prompting an investigation into the presence of dengue in the cerebrospinal fluid, which returned positive. This case underscores the importance of considering rare neurological complications in dengue, the value of advanced diagnostic techniques and the potential effectiveness of tailored interventions in challenging cases.

Diagnostic Challenges and Imaging Considerations for Intraparotid Facial Nerve Schwannoma: A Case Report and Literature Review.

BACKGROUND A mass in the parotid gland usually indicates parotid gland neoplasia. Warthin tumors or pleomorphic adenomas are common differential diagnoses. Less frequently, other differential diagnoses and sites of origin are considered. Schwannomas are rare, benign tumors in the head and neck region. Even more rarely, these tumors occur in the intraparotid course of the facial nerve. In the following, we report about 2 patients in whom a mass in the right parotid gland was found incidentally during magnetic resonance imaging (MRI). CASE REPORT We reviewed data from the literature on intraparotid facial nerve schwannomas (IPFNS) and compared them with those from our cases. The focus was on data such as clinical history, clinical symptoms, electroneurography, and various imaging modalities, such as ultrasonography and MRI combined with diffusion-weighted imaging. CONCLUSIONS It is challenging to distinguish facial nerve schwannomas from other neoplasms. Patient's history, clinical symptoms, MRI examination with diffusion-weighted imaging, and high-resolution ultrasound imaging are decisive factors for diagnosis and should be performed when IPFNS is suspected. Diagnosis and therapy for IPFNS remain challenging. A wait-and-scan approach could be an option for patients with small tumors and good facial nerve function. On the other hand, patients with advanced tumors associated with limited facial nerve function can benefit from surgical approaches or stereotactic radiosurgery.

[Analysis of the outcome of 12 cases of facial nerve tumors].

Objective:This study aims to provide a comprehensive summary of the pathogenesis, screening modalities, treatment strategies, repair modalities and preliminary results associated with facial nerve tumors. Methods:A retrospective analysis was conducted on the clinical data of 12 patients with facial nerve tumors who were admitted to our department between May 2018 and February 2023. The study population consisted of 5 males and 7 females, with ages ranging from 35 to 90 years. Clinical symptoms observed in these patients included facial nerve palsy, hearing loss, tinnitus, headache, and otalgia, etc. The severity of facial nerve dysfunction was assessed using the House-Brackmann（H-B） facial nerve function classification, with 3 cases classified as grade Ⅰ, 4 cases as grade Ⅲ, 2 cases as grade Ⅳ, and 3 cases as grade Ⅴ. There was a total of 11 patients who presented with hearing loss. Among these patients, 7 cases were diagnosed with conductive hearing loss, 2 cases with sensorineural hearing loss, and 2 cases with mixed hearing loss. The selection of the observation or surgical route for tumor localization was based on clinical symptoms, facial nerve function grading, and imaging examination results including temporal bone CT and enhanced MRI. Specifically, the location of the tumor was selected for observation or the best surgical route: 2 cases were followed up for observation, 1 case underwent biopsy, and 9 cases underwent tumor resection（7 cases of trans-mastoid approach, 2 cases of combined parotid-mastoidal approach）, concurrent repair of the facial nerve（4 cases of auricular nerve grafting, 3 cases of facial nerve diversion anastomosis, 2 cases of peroneal nerve grafting）. （4 cases of auricular nerve graft, 3 cases of facial nerve diversion anastomosis and 2 cases of peroneal nerve grafting）. Periodic postoperative evaluation of facial nerve function was conducted. Results:1-year follow-up was available. Intraoperatively, it was observed that 66.7%（6 out of 9） of the facial nerve tumors were present in multiple segments. Among these segments, the vertical segment had the highest proportion, accounting for 77.8%（7 out of 9）, followed by the labyrinthine segment/geniculate ganglion with 66.7%（6 out of 9） and the horizontal segment with 55.6%（5 out of 9）. Postoperative pathology confirmed 8 cases with nerve sheath meningioma, Ⅰ with seminal fibroma and 1 with hemangioma. Postoperative facial nerve function was graded as H-B grade I in one patient）, grade Ⅲ in three, grade Ⅳ in four, grade Ⅴ in 2, and grade Ⅵ in 2 patients. The auditory outcomes following surgery are as follows: 8 individuals experienced postoperative hearing loss, while 2 individuals demonstrated postoperative hearing preservation. Conclusion:In the case of patients presenting with facial nerve palsy as their initial symptom, it is imperative to consider the potential presence of a facial nerve tumor. To determine the appropriate course of action, it is necessary to ascertain the size and location of the tumors through imaging examinations. This information will aid in the decision making process regarding whether surgical intervention is warranted, and so, the most suitable approach. Additionally, the choice of repair method during the operation should be guided by the extent of facial nerve defect.