Evolution in the management of facial nerve schwannoma

Long-term follow-up results of facial nerve schwannoma with good facial nerve function: a multicenter study

PURPOSE

Facial nerve schwannomas (FNSs) are rare intracranial tumors, and the optimal management of these tumors remains unclear. We investigated the long-term follow-up results of FNS with good facial nerve function.

METHODS

At nine medical centers in the Korean Facial Nerve Study Group, 43 patients undergoing observation periods longer than 12 months for FNS with good facial nerve function (House-Brackmann grade ≤ II) were enrolled, and clinical and radiographic data were obtained for these cases.

RESULTS

The mean follow-up period was 63 months. In the majority of cases, tumors involved multiple segments (81.4%) and only eight cases were confined to a single site. There were no cases where the tumor was confined to the extratemporal region. Tumor size increased slightly, with an average estimated change of 0.48 mm/year. Twenty (46.5%) of 43 patients showed no change in tumor size. Seven patients (16.3%) showed worsening House-Brackmann (H-B) grade, of which two patients deteriorated from H-B grade I to II, four worsened to grade III, and one deteriorated to grade IV. The remaining 36 patients (83.7%) showed no change in facial nerve function. There was no difference in H-B grade according to tumor size at the time of diagnosis or change in tumor size.

CONCLUSION

We conducted a large-scale observational study of FNS with good facial nerve function. Our study showed that many patients maintained facial nerve function during long-term follow-up. Conservative management with regular examination and imaging can be an appropriate option for managing FNS with good facial nerve function.

Surgical results for one-stage VII/VIII schwannoma resection and hemihypoglossal-facial neurorrhaphy

BACKGROUND

This retrospective study evaluated the outcomes of patients undergoing one-stage resection of VII/VIII schwannomas and hemihypoglossal-facial neurorrhaphy via the translabyrinthine approach (TLA).

METHODS

The study encompassed ten consecutive patients with unilateral hearing loss (six women, four men, mean age: 49.5 ± 12.1 years) who underwent surgery. The cohort included two patients with vestibular schwannomas (VSs), four with facial nerve schwannomas (FNSs) (two originating from the geniculate ganglion of the facial nerve and two from the cerebellopontine angle), one with VS regrowth, and three with residual VSs. Preoperative facial nerve function, assessed using the House-Brackmann (HB) scale, was Grade V in one and Grade VI in nine patients. The mean preoperative duration of facial paralysis was 7.5 ± 6.9 months.

RESULTS

All patients underwent gross total resection. Postoperatively, one patient experienced cerebrospinal fluid leaks, which were successfully managed with lumbar drains and surgical revisions. At follow-up, facial nerve function improved in all patients: HB Grade V to III in one, HB Grade VI to III in one, HB Grade VI to IV in seven, and Grade VI to V in one. No tumor recurrence was observed during the follow-up period (mean duration: 16.6 ± 9.3 months), and no patient had hemilingual atrophy.

CONCLUSION

The TLA for one-stage resection of VII/VIII schwannomas and facial nerve reconstruction is effective in treating both regrowth and residual VSs and FNSs in the cerebellopontine angle or petrosal bone in patients with severe preoperative facial palsy. This technique facilitates simultaneous tumor removal and nerve anastomosis, thereby reducing the need for multiple surgical interventions in patients with hearing loss and compromised facial nerve function.

Task force of the Brazilian Society of Otology - evaluation and management of peripheral facial palsy

OBJECTIVE

To review key evidence-based recommendations for the diagnosis and treatment of peripheral facial palsy in children and adults.

METHODS

Task force members were educated on knowledge synthesis methods, including electronic database search, review and selection of relevant citations, and critical appraisal of selected studies. Articles written in English or Portuguese on peripheral facial palsy were eligible for inclusion. The American College of Physicians' guideline grading system and the American Thyroid Association's guideline criteria were used for critical appraisal of evidence and recommendations for therapeutic interventions.

RESULTS

The topics were divided into 2 main parts: (1) Evaluation and diagnosis of facial palsy: electrophysiologic tests, idiopathic facial palsy, Ramsay Hunt syndrome, traumatic peripheral facial palsy, recurrent peripheral facial palsy, facial nerve tumors, and peripheral facial palsy in children; and (2) Rehabilitation procedures: surgical decompression of the facial nerve, facial nerve grafting, surgical treatment of long-term peripheral facial palsy, and non-surgical rehabilitation of the facial nerve.

CONCLUSIONS

Peripheral facial palsy is a condition of diverse etiology. Treatment should be individualized according to the cause of facial nerve dysfunction, but the literature presents better evidence-based recommendations for systemic corticosteroid therapy.

Facial Reanimation After Intratemporal Facial Nerve Schwannoma Resection: A Systematic Review

Objective: To systematically analyze the outcomes of reanimation techniques that have been described for patients undergoing non-fascicle sparing resection of intratemporal facial schwannomas. Methods: A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines of the PubMed, MEDLINE, and Cochrane Central Register of Controlled Trials databases. Results: Eight hundred forty studies were screened with 22 meeting inclusion criteria comprising 266 patients. Most facial nerve reanimations (81.2%) were performed using an interposition nerve graft. The remaining patients underwent hypoglossal-facial nerve transposition (13.9%), primary anastomosis (3.4%), and free muscle transfer (0.1%). Of the reported interposition grafts, the two most utilized were the great auricular (113/199) and sural (86/199) nerves. Interposition nerve grafts resulted in significantly better outcomes in facial nerve function postoperatively than hypoglossal-facial transposition (3.48 vs. 3.92; p < 0.01). There was no difference between interposition grafts. Conclusion: This study systematically reports that interposition nerve grafts, after resection of intratemporal facial schwannoma, result in superior outcomes than hypoglossal-facial nerve transposition in these patients.

Endoscopic approach to geniculate ganglion: a multicentric experience

PURPOSE

A variety of lesions could arise from the GG area, or extend into this region from adjacent sites. The management of perigeniculate lesions includes observation, surgery, and radiation, according to the nature, the size of the lesion, and the accompanying symptoms. Preliminary experiences on the exclusive transcanal endoscopic approach to the GG area have shown safety and feasibility avoiding of any postauricular incision, or brain manipulation. The experience from two referral centers on patients treated for a GG lesion with a totally endoscopic approach is herein reported.

METHODS

Data about patients who underwent exclusive endoscopic approach to the GG area at the Otolaryngology Departments of the University Hospitals of Modena and Bologna between May 2017 and February 2022 were retrospectively collected.

RESULTS

The total number of patients included in our study was 11. 10 patients (91%) had progressive unilateral facial paralysis and 1 patient (11%) presented with chronic otorrhea. The mean largest diameter of the treated lesions was of 8 mm. The resection was extended to the fundus of the IAC in 2 patients (expanded approach). The remaining 9 patients (82%) underwent partial ossicular replacement prosthesis (PORP). No major complications occurred. Facial nerve outcomes were good in all patients and the mean ABG worsened from 12 dB pre-operatively to 22 dB post-operatively.

CONCLUSIONS

The exclusively endoscopic approach to GG lesions represents a viable alternative to traditional microscopic approaches and may be included in the armamentarium of ear surgeons.

Characteristics and Management of Facial Nerve Schwannomas and Hemangiomas

OBJECTIVES

To characterize facial nerve (FN) schwannomas (FNSs) and FN hemangiomas (FNHs) and their clinical features and management strategies, and to describe the results of cable nerve grafting after FN sectioning during tumor removal.

METHODS

This retrospective study included 84 FNS cases and 42 FNH cases managed between July 1989 and July 2020 at a quaternary referral center for skull base pathology. Clinical details, locations, management, and results of cable nerve grafting at 1 year and during an average period of 3.12 years were evaluated. Sural nerve interpositioning was performed for patients who experienced FN paralysis for less than 1 year and underwent nerve sectioning during tumor removal.

RESULTS

FNSs more often involved multiple segments compared with FNHs. The cerebellopontine angle and the mastoid segments were involved in 16 (19.1%) and 34 (40.5%) FNS cases, respectively; however, the cerebellopontine angle and the mastoid segments were involved in 0 and 7 (16.7%) FNH cases, respectively. Sectioned nerves of 99 patients (78.6%) were restored using interposition cable grafting. At the last follow-up evaluation, 56.3% of FNSs and 60.7% of FNHs attained House-Brackmann (HB) grade III. Lower preoperative HB grades were associated with poorer postoperative outcomes. For FNSs, the mean HB grades were 4.13 at 1 year postoperatively and 3.75 at the last follow-up evaluation ( p = 0.001); however, for FNHs, the mean HB grades were 4.04 postoperatively and 3.75 at the last follow-up evaluation. Therefore, extradural coaptation yielded better outcomes.

CONCLUSION

FNSs can occur along any part of the FN along its course, and FNHs are concentrated around the area of geniculate ganglion. The results of cable inter positioning grafts are better in patients with preoperative FN-HB-III or less when compared with higher grades. The outcome of the interpositioning continues to improve even after 1 year in extradural coaptation.

Long-term outcomes of stereotactic radiosurgery for intracranial schwannoma in neurofibromatosis type 2: a genetic analysis perspective

PURPOSE

Neurofibromatosis type 2 (NF2) is intractable because of multiple tumors involving the nervous system and is clinically diverse and genotype-dependent. Stereotactic radiosurgery (SRS) for NF2-associated schwannomas remains controversial. We aimed to investigate the association between radiosurgical outcomes and mutation types in NF2-associated schwannomas.

METHODS

This single-institute retrospective study included consecutive NF2 patients with intracranial schwannomas treated with SRS. The patients' types of germline mutations ("Truncating," "Large deletion," "Splice site," "Missense," and "Mosaic") and Halliday's genetic severity scores were examined, and the associations with progression-free rate (PFR) and overall survival (OS) were analyzed.

RESULTS

The study enrolled 14 patients with NF2 with 22 associated intracranial schwannomas (median follow-up, 102 months).　The PFRs in the entire cohort were 95% at 5 years and 90% at 10-20 years. The PFRs tended to be worse in patients with truncating mutation exons 2-13 than in those with other mutation types (91% at 5 years and 82% at 10-20 years vs. 100% at 10-20 years, P = 0.140). The OSs were 89% for patients aged 40 years and 74% for those aged 60 years in the entire cohort and significantly lower in genetic severity group 3 than in the other groups (100% vs. 50% for those aged 35 years; P = 0.016).

CONCLUSION

SRS achieved excellent PFR for NF2-associated intracranial schwannomas in the mild (group 2A) and moderate (group 2B) groups. SRS necessitates careful consideration for the severe group (group 3), especially in cases with NF2 truncating mutation exons 2-13.

A Large Intratemporal Facial Nerve Schwannoma Presenting as an Occluding External Auditory Canal Mass

Facial nerve schwannomas are rare, benign, slow-growing tumors that can occur in any segment of the facial nerve, although 71% of cases are intratemporal. Surgical resection can lead to facial nerve injury. Facial function recovery after reanimation is usually not better than House-Brackmann (HB) grade III. Thus, for cases of intratemporal facial nerve schwannomas (IFNSs) with favorable facial function (HB grade I or II), observation by periodic magnetic resonance imaging is the mainstay of management. Here, we present a case of a large IFNS with normal facial function in which the mass fully occluded the external auditory canal. The occlusion caused squamous debris to accumulate, potentially leading to cholesteatoma. Faced with this therapeutic dilemma, we chose surgical resection with the patient's informed consent. Stripping surgery was achieved with normal postoperative facial function. There was no postoperative facial paralysis or recurrence at 2-year follow-up. We describe the experience of diagnosis and treatment process for this case, and discuss the possibility of total resection of the tumor with preserving the integrity of facial nerve.

Detection of the Moment of Nerve Decompression Using Continuous Monitoring of Evoked Facial Nerve Electromyograms in a Patient with Facial Nerve Schwannoma: Case Report

Facial nerve function improvement is a challenging goal in facial nerve schwannoma (FNS) surgery. Intraoperative continuous monitoring of evoked facial nerve electromyograms (CFN-EMGs) is performed in acoustic neuroma surgery to preserve facial nerve function. CFN-EMGs were applied in decompression surgery for FNS with severe facial paresis. A 39-year-old woman presented with a sudden onset of vertigo, left hearing disturbance, and severe left facial palsy with House-Brackmann (HB) grade 5. FNS was strongly suspected based on the patient's clinical course and magnetic resonance imaging findings, and the patient underwent surgical decompression of the internal auditory canal (IAC) to improve facial nerve function 9 weeks after onset. CFN-EMG responses suddenly improved after removing the posterior wall of the IAC and incising its dura matter. Since the patient's facial nerve paresis improved to HB grade 2 after surgery, CFN-EMGs could detect the moment of facial nerve decompression. This would be the first report to show that CFN-EMGs applied in decompression surgery for FNS could detect the effects of decompression during surgery in real-time. Thus, CFN-EMGs may be an effective monitoring method in decompression surgery for FNS.

Giant Facial Nerve Schwannoma with Extra-Temporal Involvement: A Series Of Two Cases

Facial nerve schwannoma is a rare benign tumor of temporal bone arising from the schwann cells with incidence of 0.8%. They can arise from any segment of facial nerve with geniculate ganglion being the most common and labyrinthine segment the second commonest site. Intra-temporal location is common while only 9% of the cases have extra-temporal or parotid gland involvement. Bony remodeling or scalloping of the facial canal and the surrounding bone is the classic radiological feature of schwannoma. However schwannomas of temporal bone location can show bony erosions. The management option depends on site, extent, facial nerve function and hearing status. Surgery is reserved for large tumors with poor facial functions, hearing loss and giddiness. Giant facial nerve schwannoma with extra-temporal involvement is a rare entity with only handful number of cases reported in the literature. We present a series of two cases of giant facial nerve schwannoma with parotid gland involvement.

Safety and Efficacy of Hypofractionated Stereotactic Radiosurgery in Facial Nerve Schwannoma

OBJECTIVE

In the current era of modern neurosurgery, the treatment strategies have been shifted to "nerve-preservation approaches" for achieving a higher facial and hearing function preservation rate following facial nerve tumors. We have conducted this novel report on determining the outcome of patients with facial nerve schwannomas (FNS) treated with hypofractionated stereotactic radiosurgery (hfSRS).

PATIENTS

Retrospective chart review of a prospectively maintained database search was conducted.

INTERVENTION

Patients who underwent hfSRS CyberKnife (Accuray Inc, Sunnyvale, CA, U.S.A.) for FNS were included.

MAIN OUTCOME MEASURES

Outcomes consisted of tumor control, facial and hearing nerve function as graded by House-Brackmann and American Academy of Otolaryngology-Head and Neck Surgery recommendations, and adverse radiation effects.

RESULTS

With an institutional board review approval, we retrospectively identified five patients with FNS (four intracranial [80%] and one extracranial [20%]) treated with hfSRS (2011-2019). Patients received definitive SRS in three patients (60.0%), whereas adjuvant to surgical resection in two patients (40.0%). A median tumor volume of 7.5 cm3 (range, 1.5-19.6 cm3) received a median prescription dose of 23.2 Gy (range, 21-25 Gy) administered in median of three fractions (range, three to five sessions). With a median radiographic follow-up of 31.4 months (range, 13.0-71.0 mo) and clinical follow-up of 32.6 months (range, 15.1-72.0 mo), the local tumor control was 100.0%. At the last clinical follow-up, the facial nerve function improved or remained unchanged House-Brackmann I-II in 80.0% of the patients, whereas the hearing nerve function improved or remained stable in 100.0% of the patients. Temporary clinical toxicity was observed in three patients (60.0%), which resolved. None of the patients developed adverse radiation effect.

CONCLUSION

From our case series, hfSRS in FNS seems to be safe and efficacious in terms of local tumor control, and improved facial and hearing nerve function.

Intratemporal Facial Nerve Schwannomas: A Review of 45 Cases in A Single Center

There are no established indications for facial nerve schwannoma treatment, including surgery, radiation and follow-up observation, and it is difficult to determine treatment policy uniformly. The treatment policy was examined from each treatment course. Data of patients with facial nerve schwannomas at our hospital from 1987 to 2018 were retrospectively examined. Their age, sex, clinical symptoms, tumor localization, treatment policies and outcomes were reviewed. In total, 22 patients underwent surgery and 1 patient underwent radiotherapy; 22 patients were followed up without treatment. After total resection, there were no tumor recurrences, and most patients had grade 3 or 4 postoperative facial paralysis. After subtotal resection, tumor regrowth was observed in four patients and reoperation was required in two patients. Facial nerve function was maintained in four patients and was decreased in two patients. During follow-up, six patients showed tumor growth. Only one patient had worsening facial nerve paralysis; four patients underwent facial nerve decompression owing to facial nerve paralysis during follow-up. If the tumor compresses the brain or it is prone to growth, surgery may be indicated, and when the preoperative facial nerve function is grade ≤ 3, consideration should be given to preserving facial nerve function and subtotal resection should be indicated. If the preoperative facial nerve function is grade ≥ 3, total resection with nerve grafting is an option to prevent regrowth. If there is no brain compression or tumor growth, the follow-up is a good indication, and decompression should be considered in facial nerve paralysis cases.

Facial Nerve Schwannoma Resection and Nerve Anastomosis in One Stage by Translabyrinthine Approach

Facial nerve schwannomas (FNS) are rare benign tumors that can develop in any segment of the facial nerve. Patients often experience facial palsy and hearing loss after FNS removal or even before surgery^1-3. Double-stage treatment is usually necessary for tumor resection and reconstruction of facial nerve function^4,5. This video describes the translabyrinthine approach for resection of the middle-posterior cranial fossa dumbbell FNS and end-to-side hypoglossal-facial nerve anastomosis in one stage. The case presented is of a 28-year-old female patient who suffered from right side hearing loss for 1.5 years, right facial paralysis for 2 months (House-Brackmann grade V), and a right middle-posterior fossa dumbbell FNS extending from right cerebellopontine angle area and internal auditory canal. Gross total resection of the tumor and hypoglossal-facial nerve end-to-side anastomosis were performed during the same procedure. Postoperative facial nerve function was House-Brackmann grade III at 6 months follow-up. The patient experienced no postoperative complications. This case demonstrates the advantages of the translabyrinthine approach for middle-posterior fossa dumbbell FNS. This approach helps in achieving tumor resection and nerve anastomosis in one stage by avoiding multiple surgical interventions for patients with hearing loss and impaired facial nerve function.The patient consented to surgery and the publication of her images.

Resection of a Dumbbell-Shaped Facial Nerve Schwannoma With Preservation of Facial Nerve Function Through the Extended Middle Fossa Approach: 2-Dimensional Operative Video

Facial nerve schwannomas are rare and can arise from any segment along the course of the facial nerve.1 Their location and growth patterns present as distinct groups that warrant specific surgical management and approaches.2 The management challenge arises when the facial nerve maintains good function (House-Brackmann grade I-II).3 Hence, a prime goal of management is to maintain good facial animation. In large tumors, however, resection with facial nerve function preservation should be sought and is achievable.4,5  While tumors originating from the geniculate ganglion grow extradural on the floor of the middle fossa, they may extend via an isthmus through the internal auditory canal to the cerebellopontine angle forming a dumbbell-shaped tumor. Despite the large size, they may present with good facial nerve function. These tumors may be resected through an extended middle fossa approach with preservation of facial and vestibulocochlear nerve function.  The patient is a 62-yr-old man who presented with mixed sensorineural and conductive hearing loss and normal facial nerve function. Magnetic resonance imaging (MRI) revealed a large tumor involving the middle fossa, internal auditory meatus, and cerebellopontine angle.  The tumor was resected through an extended middle fossa approach with a zygomatic osteotomy and anterior petrosectomy.6 A small residual was left at the geniculate ganglion to preserve facial function. The patient did well with hearing preservation and intact facial nerve function. He consented to the procedure and publication of images.  Image at 1:30 © Ossama Al-Mefty, used with permission. Images at 2:03 reprinted from Kadri and Al-Mefty,6 with permission from JNSPG.

Facial reanimation with interposition nerve graft or masseter nerve transfer: a comparative retrospective study

Both interposition nerve grafts and masseter nerve transfers have been successfully used for facial reanimation after irreversible injuries to the cranial portion of the facial nerve. However, no comparative study of these two procedures has yet been reported. In this two-site, two-arm, retrospective case review study, 32 patients were included. Of these, 17 patients (eight men and nine women, mean age 42.1 years) underwent interposition nerve graft after tumor extirpation or trauma between 2003 and 2006 in the Ear Institute, School of Medicine, Shanghai Jiao Tong University, China, and 15 patients (six men and nine women, mean age 40.6 years) underwent masseter-to-facial nerve transfer after tumor extirpation or trauma between November 2010 and February 2016 in Shanghai Ninth People's Hospital, China. More patients achieved House-Brackmann III recovery after masseter nerve repair than interposition nerve graft repair (15/15 vs. 12/17). The mean oral commissure excursion ratio was also higher in patients who underwent masseter nerve transfer than in patients subjected to an interposition nerve graft. These findings suggest that masseter nerve transfer results in strong oral commissure excursion, avoiding obvious synkinesis, while an interposition nerve graft provides better resting symmetry. This study was approved by the Institutional Ethics Committee, Shanghai Ninth People's Hospital, China (approval No. SH9H-2019-T332-1) on December 12, 2019.

Interposition Grafting of the Facial Nerve After Resection of a Large Facial Nerve Schwannoma: 2-Dimensional Operative Video

Facial nerve schwannomas can develop at any portion of the facial nerve.1 When arising from the mastoid portion of the facial nerve, the tumor will progressively erode the mastoid, giving the schwannoma an aggressive radiological appearance.1,2 The facial nerve is frequently already paralyzed, or no fascicles can be saved during resection. In these cases, end-to-end interposition grafting is the best option for facial reanimation.1,3-5 The healthy proximal and distal facial nerves are prepared prior to grafting. The great auricular nerve is readily available near the surgical site and represents an excellent graft donor with minimal associated morbidity.4,6 We demonstrate this technique through a case of a 48-yr-old male who presented with a complete right-sided facial nerve palsy due to a large facial schwannoma that invaded the mastoid and extended to the hypoglossal canal, causing hypoglossal nerve paralysis, and petrous carotid canal. His 4-yr follow-up showed no recurrent tumor with restored facial nerve function palsy to a House-Brackman grade III, and full recovery of his hypoglossal nerve function. The patient consented to the surgery and the publication of his image.

Surgical management of intraoperatively diagnosed facial nerve schwannoma located at internal auditory canal and cerebellopontine angle - our experiences of 14 cases

BACKGROUND

Facial nerve schwannomas located at internal auditory canal and cerebellopontine angle (IAC/CPA FNS) were diagnosed intraoperatively, it poses a therapeutic dilemma to the surgeon.

OBJECTIVE

To report our experience in managing IAC/CPA FNS and to propose a treatment strategy.

METHODS

A total of 14 patients with IAC/CPA FNS who were diagnosed intraoperatively and treated by operation between 2015 and 2019 were retrospectively studied.

RESULTS

Unilateral hearing loss was the most common symptom and all these patients had normal facial nerve function preoperatively. Surgical approaches used in these patients including translabyrinthine (2 cases), retrosigmoid (RS) (11 cases), and middle cranial fossa (MCF) approach (1 case). Eight patients underwent partial resection, three patients underwent subtotal resection and three patients had complete tumor removal with facial nerve reconstruction. All partial resection patients and two patients underwent subtotal resection achieved a long-term HB grade I facial nerve function. The long-term facial nerve function of patients underwent complete resection and nerve grafting was no better than HB grade III.1 of the eight patients underwent partial resection experienced tumor regrowth during the follow-up.

CONCLUSIONS

Partial or subtotal resection for IAC/CPA FNS may provide an opportunity of retaining excellent facial nerve function. Regular postoperative imaging is helpful to monitor the recurrence.

Preoperative Differences in Intracranial Facial Versus Vestibular Schwannomas: A Four Nerve Assessment

OBJECTIVES

Assesses whether preoperative functional testing can distinguish vestibular schwannomas from facial nerve schwannomas medial to the labyrinthine segment.

STUDY DESIGN

Retrospective cohort.

METHODS

Retrospectively review surgically managed intracranial facial and vestibular schwannomas between January 2015 and December 2019 at two tertiary care centers. Patients with neurofibromatosis 2 and surgery for recurrence were excluded. Preoperative functional testing to include House-Brackmann scores, electroneuronography (ENoG), cervical vestibular evoked myogenic potentials (cVEMP), caloric testing, acoustic brainstem responses (ABRs), acoustic reflexes, and audiograms was compared between the two groups of schwannomas.

RESULTS

Twelve facial and 128 vestibular schwannomas met inclusion criteria. In only one case was a facial schwannoma diagnosed preoperatively from imaging. No statistically significant difference was found in preoperative House-Brackmann scores, ENoG, cVEMP, caloric testing, ABRs, or acoustic reflexes. Pure tone average was worse in the vestibular schwannoma group (63 dB [95% CI: 58-68 dB] vs. 46 dB [95% CI: 34-58 dB], P = .01), and the difference was more apparent in the lower frequencies. Word recognition score was better in the facial schwannoma group (66% [95% CI: 45-86%] vs. 41% [95% CI: 34-47%], P = .02).

CONCLUSION

Specialized preoperative functional evaluation of the nerves of the internal auditory canal cannot reliably predict the presence of an intracranial facial schwannoma. Hearing is better in facial schwannomas, particularly in the lower frequencies. This should raise the index of suspicion for an intracranial facial schwannoma, especially in candidates for hearing preservation vestibular schwannoma surgery.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:2098-2105, 2021.

Management of facial nerve schwannoma: when is the timing for surgery

PURPOSE

Although the estimated prevalence is extremely low, facial nerve schwannoma (FNS) is the most common primary tumor of the facial nerve (FN). In the present study, the outcome of surgical management in 18 patients with FNS was analyzed and an appropriate time for surgery was proposed.

MATERIALS AND METHODS

A total of 18 patients with FNS who underwent surgical management by a single surgeon from 1999 to 2018 were retrospectively analyzed.

RESULTS

Among the 18 patients, five had no facial paralysis before surgery. Near-total removal was performed in three cases, and two cases were managed with decompression. In 13 cases with various degree of preoperative facial palsy, nerve continuity was lost during surgery. FN was reconstructed using cable graft in ten cases, direct anastomosis in one case, and facial-hypoglossal nerve transfer in one case. Facial reanimation surgery without FN reconstruction was performed in one case due to a long-standing facial paralysis before surgery. Preoperative House-Brackmann (H-B) grade in all patients was significantly worse as tumor size increased. The correlation was not observed between the duration and severity of preoperative facial palsy. Analysis of 12 patients who underwent FN reconstruction revealed that all patients with good preoperative facial function (H-B grade II-III) recovered to H-B grade III after surgery (7/7, 100%). However, patients with poor preoperative facial function (H-B grade IV or worse) had only a 40% (2/5) chance of improving to grade III after surgery. Preoperative tumor size and duration of facial palsy did not affect postoperative final facial function.

CONCLUSION

We suggest that H-B grade III facial palsy is the best time for surgical intervention, regardless of the tumor size or duration of facial palsy.

Effect of Anatomic Segment Involvement on Stereotactic Radiosurgery for Facial Nerve Schwannomas: An International Multicenter Cohort Study

BACKGROUND

Facial nerve schwannomas are rare, challenging tumors to manage due to their nerve of origin. Functional outcomes after stereotactic radiosurgery (SRS) are incompletely defined.

OBJECTIVE

To analyze the effect of facial nerve segment involvement on functional outcome for these tumors.

METHODS

Patients who underwent single-session SRS for facial nerve schwannomas with at least 3 mo follow-up at 11 participating centers were included. Preoperative and treatment variables were recorded. Outcome measures included radiological tumor response and neurological function.

RESULTS

A total of 63 patients (34 females) were included in the present study. In total, 75% had preoperative facial weakness. Mean tumor volume and margin dose were 2.0 ± 2.4 cm3 and 12.2 ± 0.54 Gy, respectively. Mean radiological follow-up was 45.5 ± 38.9 mo. Progression-free survival at 2, 5, and 10 yr was 98.1%, 87.2%, and 87.2%, respectively. The cumulative proportion of patients with regressing tumors at 2, 5, and 10 yr was 43.1%, 63.6%, and 63.6%, respectively. The number of involved facial nerve segments significantly predicted tumor progression (P = .04). Facial nerve function was stable or improved in 57 patients (90%). Patients with involvement of the labyrinthine segment of the facial nerve were significantly more likely to have an improvement in facial nerve function after SRS (P = .03). Hearing worsened in at least 6% of patients. Otherwise, adverse radiation effects included facial twitching (3 patients), facial numbness (2 patients), and dizziness (2 patients).

CONCLUSION

SRS for facial nerve schwannomas is effective and spares facial nerve function in most patients. Some patients may have functional improvement after treatment, particularly if the labyrinthine segment is involved.

Rare Diseases of the Salivary Glands and of Facial Nerve

Salivary gland diseases are rare. In the European Union (EU) a disease is considered to be rare if not more than 5 of 10,000 people are affected by it. According to estimates in Germany are about 4 million people with a rare disease. In the EU are about 30 million people with rare diseases [1]. In the present work most of the described diseases of salivary glands and of the facial nerve fall in this category. They form a very heterogeneous group whose treatment takes place mainly in specialized centers. Still, it is essential for the otolaryngologist to identify and to diagnose these diseases in order to initiate the right therapeutic steps. The work is a compilation of innate andacquired rare salivary gland disorders and of rare facial nerve disorders. The etiologies of inflammatory diseases, autoimmune disorders and tumors are taken into account. For the individual topics, the current literature, if available, was evaluated and turned into summarized facts. In this context the development of new processes, diagnostics, imaging and therapy are considered. Genetic backgrounds of salivary gland tumors and the trends in the treatment of tumorous lesions of the facial nerve are picked up. Furthermore, also rare diseases of the salivary glands in childhood are described. Some of them can occur in adults as well, but differ in frequency and symptoms. Due to the rarity of these diseases, it is recommended to tread these in centers with special expertise for it. Finally, the difficulties of initiation of studies and the problems of establishing disease registries concerning salivary gland disorders are discussed. This is very relevant because these pathologies are comparatively seldom.

Facial Nerve Schwannoma Extending to Jugular Foramen: A Case Report

Facial nerve schwannoma (FNS) is a benign, slow-growing schwannoma that originates from Schwann cells. Facial nerve schwannoma is the most common tumor of the facial nerve but rare and only accounts for 0.15% to 0.8% of intracranial neurinomas. It may be manifested as asymmetric hearing loss, facial palsy, and hemifacial spasm. A 56-year-old woman was transferred to our department, because of pain behind the right ear and spasm of the right lateral muscle for more than 2 years and pulsatile tinnitus for half a year. Based on the preoperative medical history, physical signs, and auxiliary examination, it was diagnosed with jugular foramen (JF) space-occupying lesion. We removed the tumor through the infratemporal fossa type A approach and found that the tumor originated from the facial nerve. After the tumor resection, sural nerve transplantation was performed. The patient demonstrated postoperative facial palsy (House-Brackman grade VI) and was smoothly discharged after good recovery. Facial nerve schwannoma rarely invades the JF, and the most common tumor in the JF is the glomus jugular tumor, followed by the posterior cranial schwannoma. They have common symptoms, making it difficult to obtain a correct diagnosis. Clinical data, medical history, and auxiliary examinations should be carefully analyzed to avoid misdiagnosis or mistreatment. Infratemporal fossa type A approach is an effective method for treating FNS of JF.

Long-Term Outcomes of Stereotactic Radiosurgery for Trigeminal, Facial, and Jugular Foramen Schwannoma in Comparison with Vestibular Schwannoma

Stereotactic radiosurgery (SRS) is known to provide excellent tumor control with functional preservation for vestibular schwannomas (VS), but its efficacy in the other major intracranial schwannomas including trigeminal (TS), facial (FS), and jugular foramen schwannomas (JFS) has not been established yet due to their rarity. We retrospectively analyzed data of 514 consecutive patients who had intracranial schwannomas (460 VS, 22 TS, 7 FS, and 25 JFS) and underwent SRS. The 5- and 10-year tumor control rates were 97% and 94% for VS, 100% and 100% for TS, 80% and 80% for FS, and 100% and 80% for JFS. Radiation-induced complications included one hydrocephalus for TS (4.5%), no cases for FS (0%), and one hydrocephalus and one lower palsy for JFS (8.0%). Through matched cohort analysis between patients with VS and each of the non-VS, we found no statistical difference in tumor control and radiation-induced adverse events. SRS seems to provide long-term tumor control with functional preservation for TS, FS and JFS and the efficacies are similar to VS.

Trends in the Management of Non-Vestibular Skull Base and Intracranial Schwannomas

The aim of this review is to analyze the latest trends in the management of non-vestibular skull base and intracranial schwannomas in order to optimize tumor control and quality of life. Non-vestibular cranial nerve schwannomas are rare lesions, representing 5–10% of cranial nerve schwannomas. Management decisions should be individualized depending on tumor size, location and associated functional deficits. Generally, large sized schwannomas exerting significant mass effect with increased intracranial pressure are treated surgically. In some cases, even after optimal skull base resection, it is not possible to achieve a gross total resection because tumor location and extent and/or to reduce morbidity. Thus, subtotal resection followed by stereotactic radiosurgery or fractioned radiotherapy offers an alternative approach. In certain cases, stereotactic radiosurgery or radiotherapy alone achieves good tumor control rates and less morbidity to gross total resection. Finally, given the slow growth rate of most of these tumors, observation with periodic radiographic follow-up approach is also a reasonable alternative for small tumors with few, if any, symptoms.

Intratemporal facial nerve schwannomas: multicenter experience of 80 cases

PURPOSE

To provide more data on the clinical presentation and natural evolution of facial nerve schwannomas and to provide guidance for therapeutic decision making.

METHODS

A retrospective case review of eighty patients diagnosed with a facial nerve schwannoma between 1990 and 2018 in ten tertiary referral centers in Europe was performed. Patients' demographics, symptomatology, audiometry, anatomical site (segments involved), size and whenever possible volume measurement were registered.

RESULTS

At presentation, transient or persistent facial palsy was the most common symptom, followed by hearing loss. The schwannoma involved more than one segment in the majority of the patients with the geniculate ganglion being most commonly involved. Initial treatment consisted of a wait and scan approach in 67.5%, surgery in 30% and radiation therapy in 2.5% of the patients. Tympanic segment schwannomas caused mainly conductive hearing loss and were more prone to develop facial palsy at follow-up. Internal auditory canal or cerebellopontine angle schwannomas presented with significantly more sensorineural hearing loss.

CONCLUSIONS

Although modern imaging has improved diagnosis of this tumor, choosing the best treatment modality remains a real challenge. Based on the literature review and current findings, more insights into the clinical course and the management of facial nerve schwannomas are provided.

Long-term results of Gamma Knife radiosurgery for facial nerve schwannomas

OBJECTIVE

Long-term outcomes of eleven cases of facial nerve schwannoma were evaluated and the related literature was reviewed to determine the efficacy of Gamma Knife radiosurgery for treating patients with facial nerve schwannoma.

METHODS

Eleven patients with facial nerve schwannoma (7 women and 4 men; mean age, 44.2 years; range, 19-73 years) underwent Gamma Knife radiosurgery. The most common symptoms were facial palsy (n = 10) and hearing loss (n = 7). Five patients presented with headache. Two patients had undergone prior resection. The patients' clinical and radiographic data were evaluated retrospectively.

RESULTS

For the 11 cases of facial nerve schwannoma, mean tumor volume was 3.1 cm³ (range, 0.4-7.4 cm³) and the mean marginal dose applied was 11.9 Gy (range, 11-13 Gy). The mean follow-up period was 84.3 months (range, 66-117 months). Tumor control was achieved in all patients. At the time of writing, four patients experienced tumor volume regression and the other seven were in stable condition. During follow-up, nine patients experienced no change in their facial function, two experienced deteriorated facial function, and none developed new facial palsy. Ten patients who had serviceable hearing prior to Gamma Knife radiosurgery retained their hearing.

CONCLUSIONS

Gamma Knife radiosurgery achieves excellent results with respect to tumor control for 7 years on average. In addition, Gamma Knife radiosurgery provides good results in facial nerve and hearing function at long term. Our series demonstrates that Gamma Knife radiosurgery is an effective and safe treatment for patients with either primary or residual facial nerve schwannoma.

Facial Schwannoma Management Outcomes: A Systematic Review of the Literature

OBJECTIVE

To evaluate facial nerve outcomes of various management strategies for facial schwannomas by assimilating individualized patient data from the literature to address controversies in management.

DATA SOURCES

PubMed-National Center for Biotechnology Information and Scopus databases.

REVIEW METHODS

A systematic review of the literature was performed for studies regarding facial schwannomas. Studies were included if they presented patient-level data, type of intervention, pre- and postintervention House-Brackmann (HB) grades, and tumor location by facial nerve segment.

RESULTS

Individualized data from 487 patients were collected from 31 studies. Eighty (16.4%) facial schwannomas were managed with observation, 25 (5.1%) with surgical decompression, 20 (4.1%) with stereotactic radiosurgery, 225 (46.2%) with total resection, and 137 (28.1%) with subtotal resection/stripping surgery. Stripping surgery/subtotal resection with good preoperative facial nerve function maintained HB grade 1 or 2 in 96% of cases. With a total resection of intradural tumors, preoperative HB grade did not significantly affect facial nerve outcome (n = 45, P = .46). However, a lower preoperative HB grade was associated with a better facial nerve outcome with intratemporal tumors (n = 56, P = .009). When stereotactic radiosurgery was performed, 40% of patients had improved, 35% were stable, and 25% had worsened facial function. Facial nerve decompression rarely affected short-term facial nerve status.

CONCLUSION

The data from this study help delineate which treatment strategies are best in which clinical scenarios. The findings can be used to develop a more definitive management algorithm for this complicated pathology.

Surgical Outcomes of Intratemporal Facial Nerve Schwannomas According to Facial Nerve Manipulation

OBJECTIVES

The aim of this study was to evaluate the preoperative and postoperative facial nerve (FN) function in patients with FN schwannoma (FNS) and analyze the duration of preoperative facial palsy according to the preoperative and postoperative facial function.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 29 patients with FNS who underwent surgery. We evaluated the FN function according to the type of FN manipulation and location of the anastomoses in the cable nerve graft, and we also analyzed the duration of facial palsy according to the facial function before and after surgery.

RESULTS

All 4 patients who underwent nerve-stripping surgery had the House-Brackmann (H-B) Grade III, 12 of 21 who underwent a cable nerve graft had the H-B Grade III or better postoperatively, and all 4 who underwent a hypoglossal facial crossover had the H-B Grade IV. Patients who underwent cable nerve grafting were more likely to have better FN function when the proximal anastomosis site was located in the internal auditory canal, geniculate ganglion, tympanic segment of FN, and distal end in the mastoid segment of FN. The duration of preoperative facial palsy was statistically shorter in patients with better postoperative facial function.

CONCLUSION

Surgery can be considered in patients with FNS who have the H-B Grade III or worse. A shorter duration of facial palsy prior to surgery resulted in better postoperative facial function.

Facial nerve schwannoma mimicking chronic suppurative otitis media: A case report

RATIONALE

Facial nerve schwannoma (FNS) is a rare slow-growing nerve sheath tumor derived from Schwann cells. FNS with normal facial nerve function may sometimes be misdiagnosed as otitis media because of similar ontological symptoms such as purulence, tympanic membrane damage, and hearing loss.

PATIENT CONCERNS

A 68-year-old woman was referred to our department because of otorrhea and hearing loss in the right ear for 20 years. Otoscopy revealed abundant purulent secretions deep in the right external auditory canal, and granulation proliferation in the posterior part of membranae tensa. Audiogram showed a right mixed hearing loss with an 85-dB pure-tone average and 35-dB air-bone gap.

DIAGNOSIS

This patient was misdiagnosed as chronic suppurative otitis media before surgery. During surgery, a mass was found, and intraoperative frozen section histopathology confirmed an FNS.

INTERVENTIONS

This patient was subjected to mastoidectomy for curing chronic suppurative otitis media initially. During surgery, a mass was found attached and widely extended into the tympanic and mastoid segments. We removed most part of the mass, however found the mass deriving from the vertical part of the facial nerve. Intraoperative frozen section histopathology confirmed an FNS. So we removed the incurs and malleus, and searched for the edge of the mass. The mass involved multisegments of facial nerve including the tympanic, vertical and pyramidal segments. The tumor was removed completely, and nerves were repaired using greater auricular nerves.

OUTCOMES

After surgery, the patient had facial nerve paralysis of House-Brackmann (HB) Grade VI. Facial function recovered to HB Grade III at 30 months after surgery. The patient was followed up for 5 years. She had a facial function of HB grade III at the most recent follow-up.

LESSONS

FNS is rare and tend to be misdiagnosed. It is important to combine the imaging modalities of computed tomography and magnetic resonance imaging to evaluate FNS before surgery. The primary goal of managing FNS is to maintain normal facial function as long as possible; therefore, tailored strategy should be taken for managing FNS.

The Natural History of Facial Schwannomas: A Meta-Analysis of Case Series

Objective  This study is to establish predictors of facial paralysis and auditory morbidity secondary to facial schwannomas by assimilating individualized patient data from the literature. Design  A systematic review of the literature was conducted for studies regarding facial schwannomas. Studies were only included if they presented patient level data, House-Brackmann grades, and tumor location by facial nerve segment. Odds ratios (OR) were estimated using generalized linear mixed models. Main Outcome Measures  Facial weakness and hearing loss. Results  Data from 504 patients were collected from 32 studies. The geniculate ganglion was the most common facial nerve segment involved (39.3%). A greater number of facial nerve segments involved was positively associated with both facial weakness and hearing loss, whereas tumor diameter did not correlate with either morbidity. Intratemporal involvement was associated with higher odds of facial weakness (OR = 4.78, p  < 0.001), intradural involvement was negatively associated with facial weakness (OR = 0.56, p  = 0.004), and extratemporal involvement was not a predictor of facial weakness (OR = 0.68, p  = 0.27). The odds of hearing loss increased with more proximal location of the tumor (intradural: OR = 3.26, p  < 0.001; intratemporal: OR = 0.60, p  = 0.14; extratemporal: OR = 0.27, p  = 0.01). Conclusion  The most important factors associated with facial weakness and hearing loss are tumor location and the number of facial nerve segments involved. An understanding of the factors that contribute most heavily to the natural morbidity can help guide the appropriate timing and type of intervention in future cases of facial schwannoma.

Management of Facial Nerve Schwannoma: A Multicenter Study of 50 Cases

Objective  In the management of facial nerve schwannoma (FNS), surgical tumor resection is now often being replaced with more conservative approaches, such as observation with serial imaging or stereotactic radiosurgery (SRS). Given the scarcity of these lesions, determining the optimal management of FNS remains challenging and subject of debate with multiple treatment approaches supported in the literature. Methods  A retrospective chart review was performed in two academic centers for patients diagnosed with FNS between 1996 and 2017. The clinical presentation, treatment modalities employed, tumor control rates, and facial nerve function (FNF) outcomes (House-Brackmann system) were assessed and analyzed. Results  The study comprised 50 adult patients. Initial treatment modalities included observation with serial clinicoradiologic review in 27 patients (54%), surgery in 17 patients (34%), and SRS in 6 patients (12%). The FNF were decreased in more than half of the patients who had surgery. Nonetheless, more than 80% of the patients who were initially managed with observation or SRS had stable or improved FNF. Conclusion  A prevailing trend toward more conservative treatment modalities for FNS has evolved over time, providing relatively long-term preservation of FNF. As there are multiple management options available, it is of paramount importance that the treating physician be familiar with all treatment modalities and outcomes and counsel patients appropriately. The surgery should be reserved for large tumors and poor FNF at initial presentation or follow-up while watchful observation with imaging is the treatment of choice for rest of the patients.

Intra-Orbital Meningioma Causing Loss of Vision in Neurofibromatosis Type 2: Case Series and Management Considerations

Objectives: Little evidence exists regarding the management of orbital meningioma causing vision loss in the setting of neurofibromatosis Type 2 (NF2). We review here our experience with patients at risk for blindness due to intra-orbital meningioma. Design/Setting/Participants/Main Outcome Measures: The charts of patients with NF2 presenting for evaluation of intra-orbital meningioma and vision impairment between 2008 and 2013 were retrospectively reviewed in accordance with institutional IRB policies. Patients with primarily extra-orbital tumors and minimal intra-orbital extension were excluded. Charts were analyzed for the presence and/or imaging progression of intra-orbital tumor, presence of other optic apparatus pathology, presence and/ or progression of vision impairment, and intervention performed (if any). Results: Seven patients with intra-orbital meningioma on MRI and bilateral vision loss and/or unilateral visual impairment due to tumor and contralateral blindness of any etiology were identified. Patients without salvageable vision in either eye were excluded (n = 3). Diagnosis of meningioma was obtained either by biopsy or based on imaging assessment. Conclusion: Conservative management of orbital tumors in NF2 may be preferred in asymptomatic patients but may not be acceptable in patients with progressive visual decline. Radiation is a reasonable option for meningiomas of the orbit and optic nerve sheath. Finally, although the benefit of cranial nerve decompression in NF2 for preservation of facial nerve and hearing has previously been established, the role of optic nerve decompression for preservation of vision in NF2 remains poorly defined.

Evaluation and Management of Facial Nerve Schwannoma

Facial nerve schwannomas are benign peripheral nerve sheath tumors that arise from Schwann cells, and most commonly present with facial paresis and/or hearing loss. Computed tomography and MRI are critical to diagnosis. Management decisions are based on tumor size, facial function, and hearing status. Observation is usually the best option in patients with good facial function. For patients with poor facial function, the authors favor surgical resection with facial reanimation. There is growing evidence to support radiation treatment in patients with progressively worsening moderate facial paresis and growing tumors.

Case analysis of temporal bone lesions with facial paralysis as main manifestation and literature review

OBJECTIVE

This study aims to discuss clinical characteristics, image manifestation and treatment methods of temporal bone lesions with facial paralysis as the main manifestation for deepening the understanding of such type of lesions and reducing erroneous and missed diagnosis.

METHODS

The clinical data of 16 patients with temporal bone lesions and facial paralysis as main manifestation, who were diagnosed and treated from 2009 to 2016, were retrospectively analyzed. Among these patients, six patients had congenital petrous bone cholesteatoma (PBC), nine patients had facial nerve schwannoma, and one patient had facial nerve hemangioma. All the patients had an experience of long-term erroneous diagnosis.

RESULTS

The lesions were completely excised by surgery. PBC and primary facial nerve tumors were pathologically confirmed. Facial-hypoglossal nerve anastomosis was performed on two patients. HB grade VI was recovered to HB grade V in one patient. The anastomosis failed due to severe facial nerve fibrosis in one patient. Hence, HB remained at grade VI. Postoperative recovery was good for all patients. No lesion recurrence was observed after 1-6 years of follow-up.

CONCLUSION

For the patients with progressive or complete facial paralysis, imaging examination should be perfected in a timely manner. Furthermore, PBC, primary facial nerve tumors and other temporal bone space-occupying lesions should be eliminated. Lesions should be timely detected and proper intervention should be conducted, in order to reduce operation difficulty and complications, and increase the opportunity of facial nerve function reconstruction.

Upfront Gamma Knife surgery for facial nerve schwannomas: retrospective case series analysis and systematic review

INTRODUCTION

Facial nerve schwannomas are rare tumors and account for less than 2% of intracranial neurinomas, despite being the most common tumors of the facial nerve. The optimal management is currently under debate and includes observation, microsurgical resection, radiosurgery (RS), and fractionated radiotherapy. Radiosurgery might be a valuable alternative, as a minimally invasive technique, in symptomatic patients and/or presenting tumor growth.

METHODS

We review our series of four consecutive cases, treated with Gamma Knife surgery (GKS) between July 2010 and July 2017 in Lausanne University Hospital, Switzerland. Clinical and dosimetric parameters were assessed. Radiosurgery was performed using Leksell Gamma Knife Perfexion. We additionally performed a systematic review, which included 23 articles and 193 treated patients from the current literrature.

RESULTS

The mean age at the time of the GKS was 44.25 years (median 43.5, range 34-56). Mean follow-up period was 31.8 months (median 36, range 3-60). Two cases presented with facial palsy and other two with hemifacial spasm. Pretherapeutically, House-Brackmann (HB) grade was II for one case, III for two, and VI for one. The mean gross tumor volume (GTV) was 0.406 ml (median 0.470 ml, range 0.030-0.638 ml). The mean marginal prescribed dose was 12 Gy at the mean 54% isodose line (median 50%, range 50-70). The mean prescription isodose volume (PIV) was 0.510 ml (median 0.596 ml, range 0.052-0.805 ml). The mean dose received by the cochlea was 4.2 Gy (median 4.1 Gy, range 0.1-10). One patient benefited from a staged-volume GKS. At last follow-up, tumor volume was stable in one and decreased in three cases. Facial palsy remained stable in two patients (one HB II and one HB III) and improved in two (from HB III to II and from HB VI to HB III). Regarding hemifacial spasm, both patients presenting one pretherapeutically had a decrease in its frequency and intensity after GKS. All patients kept stable Gardner-Robertson class 1 at last follow-up.

CONCLUSION

In our experience, RS and particularly GKS, using standard, yet low doses of radiation, appear to be a safe and effective therapeutic option in the management of these rare tumors. The results as from our systematic review are also encouraging with satisfactory rates of clinical stabilization and/or improvement and high rate of tumor control. Complications are infrequent and mostly transient.

Translabyrinthine approach to internal auditory meatus: A retrospective study

Background

Ear and the lateral skull base surgery is challenging and yet fascinating for a Neuro-otologist. A thorough knowledge of the complex anatomy is indispensable for the surgeon in order to provide the best possible care.

Methods

The aim of the study was to highlight the present day indications for translabyrinthine approach to IAM from a Neuro-otologist perspective.

Results

There were a total of 7 patients who underwent Translabyrinthine approach at our centre. In the present study we have reported cases of Vestibular Schwannoma, Facial nerve schwannoma, Cholesteatoma involving the IAM, Meniere's disease with refractory vertigo which were managed via translabyrinthine approach. We also encountered, probably the first reported case, tuberculoma of the IAM which was clinical suspected to be vestibular schwannoma.

Conclusion

The article presents different clinical situations where this approach can be suitably utilized and has been dealt with via a retrospective study encountered at our centre.

[The tumors of the ear]

Any cutaneous lesion of the outer ear must be managed jointly by a dermatologist and an ENT, regardless of the age of the patient. The presence of a malignant cutaneous carcinoma (Squamous cell carcinoma or melanoma) of the pavilion requires a minimum extension assessment by a cervical ultrasound, CT-scan and MRI will be prescribed according to the degree of infiltration and the presence of clinics signs (lymphadenopathy, facial paralysis, cognitive impairment). A polyp of the external auditory meatus must be systematically biopsied in consultation and, if necessary, in the operating room with fresh anatomopathological analysis. Any "otitis externa", which does not progress favorably under local treatment, must lead to eliminate a tumoral pathology of the external acoustic meatus or of the middle ear. Any suspicion of cholesteatoma should lead to an ENT consultation to confirm the diagnosis and consider its treatment to limit the auditory dysfunction. Any unilateral neurosensorial hearing loss or unilateral vestibular involvement with normal otoscopy should lead to eliminate a inner ear tumor by an MRI of the inner ear and the ponto-cerebellar angle in millimeter sections.

Surgical Management of Intrinsic Tumors of the Facial Nerve

BACKGROUND

Intrinsic tumors of the facial nerve are a rare entity. Dealing with this subset of tumors is challenging both in terms of decision making and surgical intervention.

OBJECTIVE

To review the outcomes of surgical management of facial nerve tumors and cable nerve graft interpositioning.

METHODS

A retrospective analysis was performed at a referral center for skull base pathology. One hundred fifteen patients who were surgically treated for facial nerve tumors were included. In case of nerve interruption during surgery, the cable nerve interpositioning technique was employed wherein the facial nerve palsy lasted for less than 1-yr duration. In cases of facial nerve palsy lasting for greater than 1 yr, the nerve was restituted by a hypoglossal facial coaptation.

RESULTS

Various degrees of progressive paralysis were seen in 84 (73%) cases. Sixty nine (60%) of the tumors involved multiple segments of the facial nerve. Sixty-two (53.9%) tumors involved the geniculate ganglion. Seventy four (64.3%) of the cases were schwannomas. Hearing preservation surgeries were performed in 60 (52.1%). Ninety one (79.1%) of the nerves that were sectioned in association with tumor removal were restituted primarily by interposition cable grafting. The mean preoperative House-Brackmann grading of the facial nerve was 3.6. The mean immediate postoperative grading was 5.4, which recovered to a mean of 3.4 at the end of 1 yr.

CONCLUSION

In patients with good facial nerve function (House-Brackmann grade I-II), a wait-and-scan approach is recommended. In cases where the facial nerve has been interrupted during surgery, the cable nerve interpositioning technique is a convenient and well-accepted procedure for immediate restitution of the nerve.

Facial Nerve Schwannomas Mimicking as Vestibular Schwannomas

Objective  The objective of this study was to identify preoperative and intraoperative findings that may aid in distinguishing facial nerve schwannomas (FNS) from vestibular schwannomas (VSs), particularly in cases limited to the internal auditory canal (IAC) and cerebellopontine angle (CPA). Study Design  This was a retrospective study. Setting  This study was set at a Tertiary Referral Center. Patients  Seventeen cases from October 2002 to July 2015 with an IAC/CPA mass presumed to be a VS who were found to have a FNS intraoperatively. Main Outcome Measures  The main outcome measures included preoperative presentation, intraoperative findings, and subsequent intervention. Results  Preoperative hearing loss and imbalance were seen in 70.5 and 64.7%, respectively. Suspicious intraoperative findings included: facial nerve incorporated intimately with the tumor capsule in 12 cases; spontaneous action potentials noted while drilling the bony IAC in 3 cases; and action potentials noted on stimulation of the entire tumor capsule in 10 cases. The mean long-term facial function was House-Brackmann grade II and the mean length of follow-up was 4.86 years. Conclusion  FNSs are rare and may be difficult to distinguish from VS preoperatively. Surgical findings that should raise concern include spontaneous action potentials during drilling the bony IAC, absence of a plane of dissection between the facial nerve and tumor, or stimulation of the tumor capsule.

A retrospective study on facial nerve schwannomas: a disease with a high risk of misdiagnosis and hearing loss

The objective is to increase awareness of facial nerve schwannomas (FNSs). Clinical data from 32 cases with FNSs who received surgical treatment from 2005 to 2015 were reviewed retrospectively. The clinical data included age, sex, presentations, duration, facial nerve function, temporal-bone high-resolution computed tomography (CT) and magnetic resonance imaging (MRI) findings, surgical approaches, and postoperative histopathological examination. 16 men and 16 women were included, aged 7-69 years. The average age at diagnosis was approximately 44 years. The mean duration of disease was 65 months, and the mean tumor diameter was 22.4 mm. A tendency of multisegment involvement was observed in 29 FNS cases. Geniculate ganglion and tympanic segments were the most commonly involved segments. Meanwhile, the incidence of misdiagnosis of this disease was 50%. We observed that when FNSs involved the proximal portion of genicular ganglion, the hearing function tended to be worse than when the FNSs only involved the genicular ganglion and/or its distal portion (p < 0.05); in such cases, the hearing loss tended to become more severe with a longer duration of the disorder (p < 0.05). Multiple segment involvement is common in patients with FNS. We need to be more aware of the hearing function when FNSs involve the proximal portion of genicular ganglion. Misdiagnoses of FNS are common, and patients can be misdiagnosed with Bell's palsy, otitis media, or other diseases. Image studies should be conducted for differential diagnosis. Once the decision to perform surgical resection was made, reconstruction of the facial nerve should be considered.

Stereotactic radiosurgery for non-vestibular cranial nerve schwanommas

Non-vestibular cranial nerve schwannomas (NVCNS) are rare lesions, representing <10 % of cranial nerve schwannomas. The optimal treatment for NVCNS is often derived from vestibular schwannomas experience. Surgical resection has been referred to as the first line treatment for those benign tumors, but significant complication rates are reported. Stereotactic radiosurgery (SRS) has arisen as a mainstay of treatment for many benign tumors, including schwanommas. We retrospectively reviewed the outcomes of NVCNS treated by SRS to characterize tumor control, symptom relief, toxicity, and the role of hypo-fractionation of SRS dose. Eighty-eight (88) patients, with ninety-five (95) NVCNS were treated with either single or multi-session SRS from 2001 to 2014. Local control was achieved in 94 % of patients treated (median follow-up of 33 months, range 1-155). Complications were seen in 7.4 % of cases treated with SRS. At 1-year, 57 % of patients had improvement or resolution of their symptoms, while 35 % were stable and 8 % had worsening or increased symptoms. While 42 % received only one session, results on local control were similar for one or multiple sessions (p = 0.424). SRS for NVCNS is a treatment modality that provides excellent local control with minimal complication risk compared to traditional neurosurgical techniques. Tumor control obtained with a multi-session treatment was not significantly different from single session treatment. Safety profile was also comparable for uni or multi-session treatments. We concluded that, as seen in VS treated with CK SRS, radiosurgery treatment can be safely delivered in cases of NVCNS.

Geniculate Ganglion Tumors: Clinical Presentation and Surgical Results

OBJECTIVE

Facial nerve tumors are rare lesions mostly located in the geniculate ganglion. This study aims to compare those tumors limited to the geniculate ganglion in terms of clinical features and postoperative outcomes.

STUDY DESIGN

Case series with chart review.

SETTINGS

University tertiary reference center.

SUBJECTS AND METHODS

Medical charts were reviewed for 17 patients who had surgery for geniculate ganglion tumor removal (10 hemangiomas, 6 schwannomas, 1 meningioma). Hemangiomas and schwannomas were compared for preoperative facial nerve function, hearing, tumor size, and postoperative outcomes.

RESULTS

Facial palsy was observed in all cases. Regarding the preoperative facial nerve function, severe facial palsy (House-Brackmann grades V and VI) was present in 70% of cases for hemangiomas and for no case of schwannoma (P = .01), although hemangiomas were significantly smaller tumors (P = .01). Hearing loss was observed in 4 cases (23.5%) and was related to tumor volume (P < .0001). A complete excision was achieved in all cases, and a facial nerve graft was performed immediately after interruption in 16 patients (94%). Postoperative facial nerve function was improved or stabilized in 94% of cases. A preoperative House-Brackman grade VI was shown as a negative factor for postoperative facial nerve function.

CONCLUSIONS

Differences in clinical presentations could help in establishing the good therapeutic option depending on the tumor type. Surgery, when indicated, is safe and effective, and postoperative outcomes are not related to tumor type.

Intracranial Facial Nerve Grafting in the Setting of Skull Base Tumors: Global and Regional Facial Function Analysis and Possible Implications for Facial Reanimation Surgery

BACKGROUND

Reconstructive surgeons may encounter patients presenting after intracranial facial nerve resection and grafting in the setting of skull base tumors, who inquire regarding progression, final facial function, and need for future operations. Study goals were to analyze global and regional facial function using established grading systems and videography, while examine variables possibly affecting outcomes.

METHODS

Between 1997 and 2012, 28 patients underwent intracranial nerve grafting. Fifteen were prospectively evaluated by three facial nerve physical therapists with the Facial Nerve Grading System 2.0 and the Sunnybrook Facial Grading Score for function and the Facial Disability Index for quality of life. Still photographs and videography were used to assess quality of motion and tone, while demographic and medical variables were analyzed regarding their effect on end results.

RESULTS

Average patient age was 41.9 years (range, 22 to 66 years), and there were 10 women and five men. Average time interval between nerve grafting and evaluations was 42.9 months (range, 12 to 146 months). Both grading scores demonstrated best outcomes in the periorbita and worst outcomes in the brow. Buccinator muscle tone also improved. The average total Facial Disability Index was 67.5 percent. Although not statistically significant, the data suggest that nerve gap length affected total resting symmetry and voluntary movement, whereas preoperative palsy and age may affect total resting symmetry. Perioperative radiation therapy, tumor type, donor nerve, and coaptation technique were not found to affect outcomes.

CONCLUSIONS

Intracranial facial nerve grafting largely provides better resting tone and facial symmetry, potentially improving end results of future intervention; however, overall voluntary facial motion is poor.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Management of intratemporal facial nerve schwannomas: The evolution of treatment paradigms from 2000-2015

Intratemporal facial nerve schwannoma (FNS) are rare benign tumors of the skull base. Many of these tumors will be detected during evaluation for symptoms suggestive of vestibular schwannoma. However, there are several signs and symptoms which can suggest the facial nerve as the origin of the tumor. Intratemporal FNS can be multiple, like “beads on a string”, or solitary lesions of the internal auditory canal. This variable tumor morphology necessitates multiple treatment options to allow patients the best chance of preservation of facial nerve function. Historically FNS were managed with resection of the nerve with cable grafting. However this leaves the patient with permanent facial weakness and asymmetry. Currently most patients find this outcome unacceptable, especially when they present with good to normal facial nerve function. Facial paralysis has a significantly negative impact on quality life, so treatment regimens that spare facial nerve function have been used in patients who present with moderate to good facial nerve function. Nerve sparing options include tumor debulking, decompression of the bony facial canal, radiosurgery, and observation. The choice of management depends on the degree of facial nerve dysfunction at presentation, hearing status in the affected ear, medical comorbidities and patient preference. Each treatment option will be discussed in detail and suggestions for patient management will be presented.