Facial Schwannoma Research Articles

Facial Nerve Schwannomas: Presentation and Our Results of Treatment Comparing Three Techniques

The facial nerve schwannoma (FNS) is a tumor originated from Schwann cells. It may appear in any part of the nerve, from its origin in the cerebellopontine angle to its extracranial branches in the parotid space. Objectives: the present study aims to present different forms of presentation, evolution and management of facial schwannomas and compare the results of the three therapeutic modalities (observation, radiotherapy and surgery) used in our observation. Material and methods: A retrospective review of all facial schwannomas cases in neuro-otology’ service at the National Institute of Neurology and neurosurgery Manuel Velasco Suarez from 2005 to 2014 have been considered for this study. Results: 12 patients consisting 9 women and 3 men in the age group of 27-82 years, with an average age of 51.3 years were identified for this study. At the beginning all the cases have showed some degree of peripheral facial paralysis as per the House- Brackmann scale (HB). They are graded into three categories: 16.6% (2) cases in grade II and V; 25% (3) of cases as grade III and 5 and 41.6% (4) cases as grade VI. Three therapeutic modalities including observation with MRI studies in 3 cases (25%), radiotherapy in 4 (33.3%) cases and surgery in 5 (41.6%) cases have been adopted. The procedure consisting of microsurgical resection alone, microsurgical resection more nerve repair with sural nerve graft inginter position (SNI) or just terminal anastomosis of the facial nerve without nerve interposition. Conclusions: The facial nerve schwannomas are manifested in different ways. Most patients with sudden and recent facial palsy recover from this disease after a systemic steroid use. The study concludes that the treatment should always be aimed to preserving the facial and auditory function.

Multicystic Facial Nerve Neurinoma: A Case Report

Facial nerve neurinoma (FNN) can present as masses in the internal auditory canal or cerebellopontine angle and may mimic an acoustic neurinoma. A 44-year-old male presented with a huge facial schwannoma extending into both the middle cranial fossa and the cerebellopontine angle but without manifesting facial nerve palsy. Neurological examination on admission revealed no deficits except for speech disturbance. Magnetic resonance images (MRIs) showed a multicystic tumor extending into the middle cranial fossa and the cerebellopontine angle, with destruction of the petrous bone. The tumor was totally grossly removed. Histological examination identified schwannoma. Facial nerve palsy is one of the most typical symptoms in patients with facial schwannoma, but is not always manifested even if the tumor extends into both the middle cranial fossa and the cerebellopontine angle. They must be differentiated both clinically and radiologically from acoustic neurinomas. J Med Cases. 2015;6(8):350-352 doi: http://dx.doi.org/10.14740/jmc2241w

Stripping surgery in intratemporal facial nerve schwannomas with poor facial nerve function

To report stripping surgery in intratemporal facial nerve schwannomas (FNS) with poor facial nerve function. We attempted stripping surgery to completely remove intratemporal FNS with nerve intact in 17 patients, and succeeded in 12 cases. Clinical features of the tumors and the surgical approach were discussed. Multi-segment involvement was present in 10 cases (58.8%). The tumors were completely removed in all cases, and facial nerve integrity was preserved in 12 patients (70.6%). Six of 12 cases (50.0%) with nerve intact obtained acceptable facial nerve recovery, two of which recovered to Grade II, compared to 2 of 5 cases (40%) with nerve grafting. Multi-segment involvement was more common in FNS. Stripping surgery could remove tumor completely with nerve intact in majority patients, and it seemed to obtain better outcomes of facial nerve.

Gamma Knife surgery for facial nerve schwannomas.

The aim of this study was to evaluate the tumor control rate and functional outcomes after Gamma Knife surgery (GKS) among patients with a facial nerve schwannoma. The authors reviewed the radiological data and clinical records for 14 patients who had consecutively undergone GKS for a facial nerve schwannoma. Before GKS, 12 patients had facial palsy, 7 patients had hearing disturbance, and 5 patients had undergone partial or subtotal tumor resection. The mean and median tumor volumes were 3707 mm(3) and 3000 mm(3), respectively (range 117-10,100 mm(3)). The mean tumor margin dose was 13.2 Gy (range 12-15 Gy), and the mean maximum tumor dose was 26.4 Gy (range 24-30 Gy). The mean follow-up period was 80.7 months (range 2-170 months). Control of tumor growth was achieved in all 12 (100%) patients who were followed up for longer than 2 years. After GKS, facial nerve function improved in 2 patients, remained unchanged in 9 patients, and worsened in 3 patients. All patients who had had serviceable hearing at the preliminary examination maintained their hearing at a useful level after GKS. Other than mild tinnitus reported by 3 patients, no other major complications developed. GKS for facial nerve schwannomas resulted in excellent tumor control rates and functional outcomes. GKS might be a good primary treatment option for patients with a small- to medium-sized facial nerve schwannoma when facial nerve function and hearing are relatively preserved.

Stereotactic radiosurgery for facial nerve schwannomas: A preliminary assessment and review of the literature

Objective. Facial nerve schwannomas (FNS) are rare tumors, and their appropriate management remains the subject of considerable debate. This report details the results of a series of patients with FNS treated with stereotactic radiosurgery (SRS) at the University of Virginia. Methods. We performed a retrospective review of the clinical and imaging outcomes of 5 patients who underwent Gamma Knife RS (GKRS) for small-to-medium-sized (< 5 mL) FNS at our institution. The study population consisted of 3 males and 2 females with a median age of 35 years. All patients presented with varying degrees of facial palsy and/or hearing dysfunction. Tumor volumes at GKRS ranged from 0.1 to 5 (median = 0.8) mL. The median maximum radiosurgical dose and tumor margin dose were 24 Gy and 12 Gy, respectively. Results. After a median follow-up period of 12 (range, 6–36) months, three tumors were radiographically smaller and two remained stable. Facial function improved in three patients, remained stable in one patient, and slightly declined from House–Brackmann grade I to II in one patient. Hearing function was preserved in three patients and deteriorated in two patients, one from Gardner–Robertson grade I to II and the other from serviceable hearing grade II to III. Conclusion. SRS appears to offer a reasonable rate of facial nerve preservation and tumor control for patients with small-to-medium-sized FNS. Considering the published outcomes achieved with resection, RS may be the preferred first-line treatment for these tumors.

Long-term outcomes of facial nerve schwannomas with favorable facial nerve function: tumor growth rate is correlated with initial tumor size

ObjectiveThe study aimed to report long-term outcomes of facial nerve schwannomas (FNS) with favorable facial nerve function by observation, and to discuss about the relationship between initial tumor size and tumor growth. Methods21 facial nerve schwannoma cases with favorable facial nerve function were managed by observation. They were divided into larger size group (size ≥10mm) and smaller size group (size <10mm) according to initial tumor size. ResultsThey were followed up for 6.4±1.7years. 18 of 21 cases (85.7%) maintained House–Brackmann Grade III or better. Growth rate of the tumors in larger size group was 72.7%, much higher than 10% in smaller size group (p<0.05). ConclusionsObservation was feasible for most FNS with favorable facial nerve function, and growth rate of the tumors was associated with tumor size.

Intraparotid facial Nerzve Schwannoma : A rare case report

Intraparotid facial nerve schwannomas are extremely rare neoplasm that presents challenge in diagnosis and management as they are rarely diagnosed preoperatively. We sought to gain insight into clinical presentation, appropriate diagnostic and management modalities which is a matter of debate. Here we present a rare case of intraparotid facial nerve schwannomas diagnosed intra-operatively and managed with surgical excision.

Facial nerve schwannoma: A case report and review of the literature.

A vestibular schwannoma, often termed an acoustic neuroma, is a type of benign primary intracranial tumor of the myelin-forming cells of the vestibulocochlear nerve. The typical clinical presentation often includes ipsilateral sensorineural hearing loss/deafness, vertigo and tinnitus. In the present study, the case of a young male patient who presented with recurrent unilateral facial palsy without hearing impairment is presented. The patient was diagnosed with vestibular schwannoma and received steroidal treatment with prednisolone for two weeks. The patient’s facial weakness recovered three weeks following treatment, however, the tumor subsequently grew. The patient then underwent Gamma Knife radiosurgery with a margin dose of 13 Gy. Six months after the radiosurgery, the tumor was stable without progression, and the patient’s facial nerve function and hearing remained intact.

Schwannome du nerf facial : rapport de 16 cas

But de la presentation To describe the characteristics, diagnosis, management and outcomes of facial nerve schwannomas (FNSs). Materiel et methodes Patients whose outpatient diagnosis was facial nerve tumor and whose intraoperative identification was FNS between 2002 and 2012 were studied. Preoperative data (audiologic data, facial nerve [FN] function, and patient symptoms, tumor location on imaging data), intraoperative data (total versus subtotal resection, and FN status), and postoperative data (audiologic data, FN function, and recurrence) were collected. Resultats Surgical removal was performed in 16 patients whose FNS were confirmed histologically and 5 patients decided on follow-up. Facial paralysis and hearing loss presented commonly. The FNS involved mostly the geniculate segment, following internal auditory canal. 16 patients were operated on, of them 14 total resection, and 2 subtotal resection. The translabyrinthine approach was performed in 9 cases, the middle fossa approach was performed in 5 cases of which 1 combined with transmastoid approach, and the TM approach was performed in 2 cases. One-stage facial nerve repair was performed in 11 cases, of them 5 facial-hypoglossal nerve anastomosis and 6 sural nerve graft. These patients showed better facial function (mainly HB grades III–IV). Partial removal kept the facial function at grade II. Conclusion The symptoms of FNS are related to its location, the patients complained mainly facial paralysis and hearing loss. MRI is indispensable for the differential diagnosis, subtotal removal may be a better choice for VS-like FNS. One-stage facial repair can give a good FN outcome.

Facial nerve schwannomas presenting as occluding external auditory canal masses: a therapeutic dilemma.

To present a series of patients with facial nerve schwannomas (FNSs) presenting as occluding external auditory canal (EAC) masses. Retrospective case series. Four patients were identified with mastoid segment FNSs occluding the EAC. Three patients presented with conductive hearing loss (CHL), and the fourth presented with facial paralysis, later developing CHL. One patient underwent conservative debulking, removing the EAC component only. Two patients were managed nonoperatively with periodic cleaning of entrapped keratin. The fourth patient received radiation therapy. Facial nerve function, canal cholesteatoma formation, and hearing. Among the patients managed with serial cleaning of entrapped keratin, one maintained normal facial function and one worsened to House-Brackmann II/VI. Facial function worsened to House-Brackmann II/VI in the patient who underwent surgical debulking. The fourth patient, who received radiation, developed complete facial paralysis. All patients accumulated keratin medial to the tumor, and all had CHL. When evaluating an EAC tumor, it is important to obtain imaging before biopsy because biopsy of a schwannoma can result in paralysis. EAC occlusion by a schwannoma presents a challenging management issue, particularly when cholesteatoma forms between the tumor and the tympanic membrane. The primary goal is maintaining normal facial function as long as possible and avoiding secondary ear canal complications. The presence of canal occlusion limits the choice of stereotactic radiation because this leads to a month-long period of tumor swelling and cutaneous sloughing. Resection and grafting are indicated when substantial facial weakness or twitch develops.

The best candidates for nerve-sparing stripping surgery for facial nerve schwannoma.

Clinical decision making for facial nerve schwannoma is particularly complicated in patients with good facial nerve function; however, an early nerve-sparing tumor resection stripping technique minimizes facial deficits associated with treatment. The present study characterized the optimal candidate for this nerve-sparing surgical strategy in patients with good facial function. Retrospective study. Nerve-sparing stripping surgery was performed on 28 patients with facial nerve schwannoma. The House-Brackmann grading system was used to assess pre- and postoperative facial function. We retrospectively analyzed pre- and postoperative facial function, duration of facial palsy, tumor size, and location and number of involved segments. The data were analyzed using Fisher exact test and independent t tests. Of the 28 patients, 18 successfully underwent stripping surgery and 16 had a favorable outcome. Favorable postoperative facial function was associated with good preoperative facial function (House-Brackmann grade [HBG] ≤II); small, localized tumors; and tumors located in the geniculate ganglion and/or its proximal portion. Patients with facial nerve schwannoma who have good preoperative facial function (HBG ≤2), tumor located in the proximal portion of the geniculate ganglion, and small tumors (<2 cm) involving one or two facial nerve segments can be the best candidates for nerve-sparing stripping surgery. 4

Facial Nerve Schwannomas: Manchester Skull Base Team Experience

Objective: There is no consensus for the management of facial nerve schwannomas (FNS). We aim to provide a structured approach to their management based on a large series over a 19-year period. Study Design: Retrospective review. Patients/material and Methods: Overall 28 FNS patients were included in the study. Mean age at diagnosis was 46.4 years (range, 22-73). Mean duration of follow-up was 48 months (range, 3-144). Results: Facial weakness was the presenting symptom in 16 patients (57%). Most patients had multisegment involvement; the internal acoustic canal (IAC) was most commonly affected (68%). Fourteen patients were initially managed conservatively; 14 patients received primary surgical intervention. Two patients failed conservative management due to deterioration in facial nerve function and underwent surgery. No patients opted for stereotactic radiotherapy. Ten patients had primary nerve grafting (HB score outcome III/IV in 7/10 patients after mean follow-up of 34 months) and five patients had a staged VII/XII transposition (HB outcome IV in 2/4 patients and HB outcome V in the other two patients [mean follow-up of 25 months, one patient missing data]). Conclusions: The philosophy of our unit in managing FNS is to preserve facial function wherever possible. There is strong evidence from this study that such an approach is valid given the high proportion of patients who had preservation of facial function over the follow-up period and the small number of tumors that showed significant growth.

Small Vestibular Schwannomas Presenting with Facial Nerve Palsy

To describe the surgical management and convalescence of two patients presenting with severe facial nerve weakness associated with small intracanalicular vestibular schwannomas (VS). Retrospective review. Two adult female patients presenting with audiovestibular symptoms and subacute facial nerve paralysis (House-Brackmann Grade IV and V). In both cases, post-contrast T1-weighted magnetic resonance imaging revealed an enhancing lesion within the internal auditory canal without lateral extension beyond the fundus. Translabyrinthine exploration demonstrated vestibular nerve origin of tumor, extrinsic to the facial nerve, and frozen section pathology confirmed schwannoma. Gross total tumor resection with VIIth cranial nerve preservation and decompression of the labyrinthine segment of the facial nerve was performed. Both patients recovered full motor function between 6 and 8 months after surgery. Although rare, small VS may cause severe facial neuropathy, mimicking the presentation of facial nerve schwannomas and other less common pathologies. In the absence of labyrinthine extension on MRI, surgical exploration is the only reliable means of establishing a diagnosis. In the case of confirmed VS, early gross total resection with facial nerve preservation and labyrinthine segment decompression may afford full motor recovery-an outcome that cannot be achieved with facial nerve grafting.

Diagnostic Dilemma of Bell's Palsy: Case of Facial Nerve Schwannoma Presenting as Acute Bell's Palsy (P3.329)

Diagnostic Dilemma of Bell's Palsy: Case of Facial Nerve Schwannoma Presenting as Acute Bell's Palsy (P3.329)

Intraoperatively Diagnosed Cerebellopontine Angle Facial Nerve Schwannoma

This study aimed to report our experience in the management of patients with intraoperatively diagnosed intracranial facial nerve schwannomas (FNSs) and propose a decision-making strategy. Twenty-three patients with FNS of the internal auditory canal and/or cerebellopontine angle operated on between 1992 and 2012 were identified. Preoperatively, all cases have been radiographically diagnosed as vestibular schwannomas. Operative procedures consisted of total tumor resection with grafting in 43.4% of patients, near-total resection leaving behind the tumor capsule overlying the facial nerve in 21.7%, total tumor resection with preservation of anatomic continuity of the facial nerve in 13%, and subtotal resection in 4.3%. Four patients (17.4%) underwent bony decompression with no tumor removal. Management of FNS diagnosed at surgery represents a significant clinical challenge. We considered total tumor resection with grafting when patients presented with preoperative facial nerve palsy (≥ grade III). Both subtotal and near-total tumor removal can be performed in patients with preoperative good facial function and/or large tumors with brainstem compression. Patients with small tumors who were selected for hearing preservation surgery can be considered for bony decompression. Fascicle preservation surgery may be an option when a clear cleavage plane between the tumor and the facial nerve is found.

Subtotal resection of facial nerve schwannoma is not safe in the long run

Conclusions: Subtotal resection of facial nerve schwannoma (FNS) could obtain favorable facial nerve function recovery, but has a high recurrence rate in the long run. Subtotal resection with about 95% tumor resected could be considered in the elderly with good facial nerve function, but is not recommended for younger patients. Subtotal resection with about 70–80% tumor resected should be replaced by complete tumor removal and nerve grafting. Objectives: To present long-term follow-up results of subtotal resection of FNS and discuss the indications for subtotal resection. Methods: We performed subtotal resection of FNS in 15 cases and they were followed up for 7 years on average. Results: In all, 93.3% of cases finally gained normal or near-normal facial nerve function (House-Brackmann (HB) grade I or II) and one case maintained grade III. Tumor recurrence or regrowth was noted in four cases (26.7%) during follow-up. Recurrence was observed in 10% of cases who had about 95% tumor resected and in 60% of cases who had 70–80% tumor resected.

Unusual acute hearing loss after gamma knife surgery for a facial schwannoma

A 34-year-old female patient suffering from right-sided facial palsy presented to our hospital. Her hearing range was within normal limits. She had undergone GKS after receiving a diagnosis of facial nerve schwannoma (FNS). On the fourth day after GKS, the patient experienced sudden onset hearing loss on the right side without aggravation of the facial palsy. Intravenous corticosteroids were administered, and her hearing function improved gradually over the course of 15 days. This is the first case report of hyperacute hearing loss after GKS for FNS.

Surgical findings to differentiate between facial nerve schwannoma and vestibular schwannoma.

ObjectivesFacial nerve schwannomas may be misdiagnosed as vestibular schwannomas (VSs) if the tumor is confined to the internal auditory canal (IAC) without involvement the geniculated ganglion or labyrinthine segment of facial nerve. Because facial nerve schwannomas may be misdiagnosed as VSs, we investigated the differences between the two.MethodsThe study included 187 patients with a preoperative diagnosis of VS. Of these, six were diagnosed with facial nerve schwannomas during surgery. We reviewed the preoperative evaluations and surgical findings of facial nerve schwannomas mimicking VSs.ResultsNo useful preoperative predictors are available for facial nerve schwannomas mimicking VSs. Facial nerve schwannomas are usually confined to the IAC. After opening the dura of the IAC, a facial nerve schwannoma can be diagnosed after identifying a normal-appearing nerve located lateral to the tumor. When this was the case, we performed facial nerve preservation surgery or decompression.ConclusionFacial nerve schwannomas can be differentiated from VSs by identifying specific findings during surgery.

側頭骨内に発生した顔面神経海綿状血管腫例

We report herein on a rare case of cavernous hemangioma of the facial nerve. The patient was a 75-year-old woman with a first episode of facial nerve paralysis who was being treated with steroid pulse therapy. However, the paralysis failed to improve and had become exacerbated during the previous few years. Ultimately her facial score was 0/40 points by the Yanagihara method. CT imaging demonstrated a tumor at the tympanic to horizontal part of the facial nerve. MRI imaging demonstrated an enhanced lesion measuring 4×7×7 mm. A facial nerve schwannoma was suspected, and the tumor was totally removed via the transmastoid approach. Based on the histopathological examination the diagnosis was a cavernous hemangioma of facial nerve origin.

Translabyrinthine resection of neurofibromatosis type 2 associated vestibular and facial schwannomas, repair of facial nerve, and placement of auditory brainstem implant

We present video of gross-total resection of a large cerebellopontine angle tumor consisting of both vestibular and facial schwannoma components via the translabyrinthine route in a patient with neurofibromatosis type 2. The facial nerve is reconstructed using a greater auricular nerve graft, and an auditory brainstem implant is placed. Prior to surgery the patient had no facial nerve function on the operative side and had lost useful hearing. He also had usable vision only on the ipsilateral side and had contralateral vocal cord paralysis. The video can be found here: http://youtu.be/IOkEND-0vhI .