Facial Schwannoma Research Articles

Facial Nerve Schwannomas of the Cerebellopontine Angle: The Mayo Clinic Experience

Background There is often controversy regarding the optimal management for patients with facial nerve schwannomas (FNSs) of the cerebellopontine angle (CPA). Methods The clinical and radiological outcomes in 14 patients with CPA FNS were retrospectively reviewed. Results Patients underwent resection with anatomic nerve preservation (n = 3), facial-hypoglossal nerve anastomosis (n = 4), gamma knife radiosurgery (GKS) (n = 6), or observation (n = 1). A total of 83% of tumors that underwent GKS were stable or decreased in size. No patient who underwent resection showed evidence of tumor recurrence; the tumor under observation remained unchanged with normal facial function at the time of the last follow-up. Facial function was decreased in 57%, stable in 14%, and improved in 29% of those who underwent microsurgery. A total of 67% of patients who underwent GKS had stable facial function. Serviceable hearing was maintained in 50% of patients in the GKS group and 67% of the tumor resection group. Mean and median follow-up was 48 and 43 months, respectively (range, 12 to 95 months). Conclusion Observation should be the primary management when encountered with FNS of the CPA in those with good neurologic function. Microsurgery or radiosurgery may be used in those with poor facial function or tumor progression.

Rare Lesions of the Cerebellopontine Angle and Internal Auditory Canal

Objectives: Vestibular and facial nerve schwannomas, meningiomas, and vascular loop account for a majority of lesions occurring in the CPA and IAC. However, other lesions are encountered in this location in less than 1% of cases. The aim of the study is to describe our experience with these rare lesions that can mimic a vestibular schwannoma. For each lesion, the management is discussed.

Facial Schwannoma: Results of a Large Case Series and State-of-the-Art Review

Objective: To report a series of 53 cases of facial schwannoma, review the current literature, and present a management algorithm.

Extradural Subtemporal Transpetrosal Approach to Facial Nerve Schwannoma

Objective:Facial nerve schwannoma (FNS) are rare tumors usually presenting as a cerebellopontine angle (CPA) mass. Rarely, FNS can present as significant mass in the middle cranial fossa. They are usually approached using intradural procedures; however, we decompressed the tumor through an extradura

Facial Nerve Schwannomas Presenting as Occluding External Auditory Canal Masses

Introduction: Facial nerve schwannomas are rare tumors of the lateral skull base. Treatment options for these tumors include observation, stereotactic radiation, and microsurgical removal. Erosion of the bony posterior canal from the descending segment of an entirely intratemporal tumor is an unusual growth pattern. With tumor in the external canal, a unique set of clinical challenges arises. We discuss the management strategies for facial schwannomas with this unusual growth pattern in patients of two disparate ages.

Facial Schwannomas: Various Presentations and their Management with Literature Review

Facial schwannomas or neuromas are rare entity. They often are confused with vestibular schwannomas on imaging, especially if they are limited to the cisternal segment of the facial nerve. Awareness regarding this entity is paramount for the early diagnosis and correct management which may differ from patient to patient. We share the different clinical presentations of this rare benign tumour and discuss their management strategies in light of the affected segment of the nerve. The results were analyzed along with review of literature. Three cases of facial schwannomas were analyzed retrospectively during last 4years and their presentation, imaging, preferred surgical approaches, intra-operative findings and post grafting results are discussed. All three patients underwent surgical excision with sural nerve cable grafting and have no recurrence till date. However, the facial paresis remained the same in one of the cases while improvement was observed in two patients. The improvement was delayed in one patient as documented by electromyography of facial muscles. Facial schwannomas are slow growing tumours with low incidence. Usual presentations can sometimes be masked. Appropriate management decision needs to be arrived after considering three determinants i.e. the patient's age, hearing status and the severity of facial paresis (House-Brackmann grading). Nerve reconstruction after excision should be performed in each case and sometimes the results may be delayed. It is thus important to keep a close surviellance during the follow up and to perform the electrophysiological tests frequently so as to detect the earliest signs of regeneration (which can be delayed up to 18months).

Facial Nerve Outcomes in Facial Nerve Schwannomas

To better understand the characteristics and outcomes of facial nerve schwannomas (FNSs) over a 30-year period. Retrospective study. Subspecialty practice at a tertiary hospital. Fifty-six patients diagnosed with FNS over a 30-year period. Preoperative data (audiologic data, facial nerve [FN] function, and patient symptoms), intraoperative data (tumor location, total versus subtotal resection, and FN status), and postoperative data (audiologic data, FN function, and recurrence) were collected. Mann-Whitney and χ2 analyses were done to determine which factors correlated with poor FN outcomes (defined as House-Brackmann ≥ 4). Of the 56 patients in this study, 53 (94.6%) underwent surgical resection of their FNS. Of those patients, 45 (84.9%) underwent total resection, and 8 (15.1%) underwent subtotal resection. Subtotal resection was associated with a statistically significant decreased risk of having postoperative HB grade ≥ 4 (odds ratio, 0.09; 95% confidence interval, 0.01-0.77; p = 0.028). Of those undergoing a subtotal resection, no patient had further tumor growth seen on postoperative magnetic resonance imaging (average time of last magnetic resonance imaging since operation, 44.9 mo). Tumor location was not statistically associated with poor FN outcome (all p > 0.05). Preoperative FN paralysis was the only preoperative clinical finding statistically associated with poor FN outcomes (p = 0.004). We have identified multiple characteristics of FNS as well as multiple factors associated with increased statistical risk of poor FN outcomes.

A case of facial nerve schwannoma found during surgery having a preoperative diagnosis of parotid pleomorphic adenoma

A case of facial nerve schwannoma found during surgery having a preoperative diagnosis of parotid pleomorphic adenoma

The intraparotid facial nerve schwannoma: a diagnostic and management conundrum

ObjectivesThe aims of the study were (1) to review the management strategy and clinical outcomes of all intraparotid facial nerve (FN) schwannomas (PFNSs) treated at a single tertiary academic center from 1975 to 2010 and (2) to summarize all previously reported cases of PFNS in the international literature. Study designA retrospective cohort study and literature review. MethodsFifteen patients were diagnosed and treated at the authors' institution from 1975 to 2010. In addition, 124 published cases were systematically reviewed. ResultsThe most common presentation of PFNS was a painless parotid mass with normal FN function. Eccentric, loosely attached intraparotid tumors underwent gross total resection with nerve preservation granting satisfactory postoperative FN function, whereas “inseparable” intraparotid tumors were observed in 8 cases with stable long-term size. Lesions that extended into the fallopian canal underwent complete resection with FN sacrifice and nerve grafting in 10 cases, whereas 1 patient received subtotal resection of the intraparotid portion with stereotactic radiotherapy targeting the intratemporal component. ConclusionsIntraparotid FN schwannomas present similar to other primary salivary gland neoplasms, making an early diagnosis challenging. Intraoperative recognition of gross tumor characteristics and early histologic diagnosis with strategic biopsy are critical. Information including tumor location and extent, preoperative FN function, and the gross relationship between the tumor and the FN may guide the surgeon toward an optimal treatment plan emphasizing long-term neurologic preservation.

Revised Surgical Strategy to Preserve Facial Function After Resection of Facial Nerve Schwannoma

Early nerve-sparing tumor resection is designed to minimize facial deficits associated with facial nerve schwannomas. This report aimed to determine optimal treatment approaches and timing in patients with facial nerve schwannomas, especially those with good facial function. Clinical decision making is complicated in patients with good facial nerve function because classical surgical treatment consists of excision of the tumor along with the involved nerve segment, followed by grafting or primary anastomosis, which can result in permanent facial deficits. Since 1995, we have conducted a nerve-preserving technique on 15 patients with facial nerve schwannomas to obtain better results after our experience with the 10 patients who underwent tumor resection and/or facial nerve reconstruction before 1995 and evaluated the surgical outcomes of all 25 patients between 1990 and 2008. The House-Brackmann (HB) grading system for facial nerve function was used to assess preoperative and postoperative functions with follow-up magnetic resonance imaging to monitor for tumor recurrence. At the final functional assessment, 7 patients had no change in facial function, 2 had improved, and 6 had worsened. Specifically, 4 patients had normal facial function, 8 had HB Grade II, and 3 had HB Grade III. To date, no clinical or radiologic evidence of recurrence has been detected in any of the patients, all of whom underwent postoperative enhanced magnetic resonance imaging at least 3 years after surgery. Facial nerve-preserving technique is recommended for resection of facial nerve schwannomas, especially in patients with good preoperative facial function. Compared with the resection-and-reconstruction technique, this method can prevent delays in presurgical deterioration of the neural fascicle and may result in better postoperative facial function.

Hearing Preservation With the Middle Cranial Fossa Approach for Neurofibromatosis Type 2

To examine hearing preservation rates, facial nerve outcomes, and tumor recurrence rates in patients with neurofibromatosis Type 2 undergoing a primary middle cranial fossa approach for vestibular schwannoma removal. Retrospective chart review. Private practice tertiary neurotology referral center. All patients with neurofibromatosis Type 2 undergoing attempted hearing preservation via a middle cranial fossa approach for removal of vestibular schwannoma from January 1, 2000, to June 1, 2010. Primary middle cranial fossa approach for removal of vestibular schwannoma. Preoperative, postoperative, and change in hearing thresholds, word recognition scores, and American Academy of Otolaryngology-Head and Neck Surgery hearing class, House-Brackmann facial nerve grade, and tumor recurrence. Class A or B hearing according to the American Academy of Otolaryngology-Head and Neck Surgery was maintained in 50% of cases, whereas 63.6% had Class A, B, or C hearing, with an average word recognition score of 93.8% at an average follow-up period of 32.5 months. Facial nerve outcomes were excellent; 75% of cases maintained House-Brackmann Grade 1, whereas 94.3% had Grade 1 or 2 at an average of 25 months after surgery. Tumor growth within the surgical field was observed radiographically in 59% of cases. In patients with neurofibromatosis Type 2, proactive treatment of smaller tumors provides a chance to maintain serviceable hearing and obtain tumor control for extended periods. When examining hearing outcomes, it is important to use word recognition scores, in addition to American Academy of Otolaryngology-Head and Neck Surgery hearing class, to better assess functionality. Although facial nerve outcomes tend to be favorable, the growth of new tumors, including facial schwannomas, may occur within the surgical field. Continued surveillance with serial magnetic resonance scans after surgery is mandatory.

Two Cases of Intraparotid Facial Nerve Schwannoma

Intraparotid facial nerve schwannomas are rare, their preoperative diagnosis is difficult, and there are controversies about how to proceed when they are suspected intraoperatively. We present two cases of intraparotid facial nerve schwannoma that were diagnosed during parotid surgery, and describe the procedure and follow-up performed.

Evolution in the management of facial nerve schwannoma

To design a treatment algorithm based on experience with facial nerve schwannomas (FNS) over a 30-year period. Retrospective chart review. Seventy-nine patients with facial nerve schwannomas seen from 1979 through 2009 at a tertiary referral private otologic practice were categorized by treatment modality. Interventions included surgical resection with grafting, bony decompression, observation, or stereotactic radiation. Outcome measures included House-Brackmann facial nerve grade before and after intervention as well as change in facial nerve grade, tumor size, involved segments of nerve, time to intervention. Thirty-seven patients (46.8%) ultimately underwent surgical excision with grafting or primary anastomosis, 21 (26.6%) underwent bony decompression alone, 15 (19.0%) were managed with observation only, and 6 (7.6%) had stereotactic radiation. Through 1995, 85% of cases had surgical resection and none had observation only. Of the 52 patients seen after 1995, 27% had surgical resection and grafting, 33% had bony decompression, 29% were managed with observation alone, and 11% had radiotherapy. Facial nerve grade was maintained or improved over the follow-up period (mean time = 3.9 years) in 78.9% of the decompression group and 100% of the observation and radiation groups compared to 54.8% of the resection group (P ≤ .012). Surgical resection and grafting, once widely accepted and practiced, has in many cases given way to observation, bony decompression, or stereotactic radiation. A wide armamentarium of options is available to the neurotologist treating facial nerve schwannomas with the ability to preserve facial function for a longer period of time.

Facial Schwannoma Treatment via Cyberknife or Decompression

Objective: Microsurgical excision of facial nerve schwannomas frequently results in facial paresis or paralysis of House-Brackmann Grade III or higher. This study’s objectives are: 1) describe alternatives to microsurgical excision of facial nerve schwannomas, specifically wide fallopian canal decompression and Cyberknife radiosurgery; and 2) describe clinical outcomes of these alternative therapies. Method: This is a case-control study of all patients undergoing excision, wide fallopian canal decompression, or Cyberknife radiosurgery at a tertiary academic referral center between 2002 and 2011. Main outcome measures were pre- and posttreatment facial nerve function, tumor control, and speech reception thresholds. Results: Eleven patients were identified (3 wide decompression, 2 Cyberknife treated, 4 observation, and 2 microsurgical excision), and mean posttreatment follow-up was 35 months. When compared with excision, all of the cases undergoing nonexcision treatments resulted in facial nerve function stable or improved, no tumor growth, and no changes in speech reception thresholds. Conclusion: While surgical excision of facial nerve schwannomas may be indicated in cases of poor facial function and impending complications, wide bony decompression, observation, and Cyberknife radiosurgery should be considered as alternative treatments to excision for patients with normal or good facial function who wish to maintain preoperative hearing thresholds.

Case 171: Facial Nerve Hemangioma

The patient’s imaging features, especially the honeycomb pattern of ossific changes in the geniculate fossa, were virtually pathognomonic for ossifying hemangioma of the facial nerve.

Toxicity of Gamma Knife Radiosurgery in the Treatment of Intracranial Tumors in Patients With Collagen Vascular Diseases or Multiple Sclerosis

To assess toxicity in patients with either a collagen vascular disease (CVD) or multiple sclerosis (MS) treated with intracranial radiosurgery. Between January 2004 and April 2009, 6 patients with MS and 14 patients with a CVD were treated with Gamma Knife radiosurgery (GKRS) for intracranial tumors. Treated lesions included 15 total brain metastases in 7 patients, 11 benign brain tumors, 1 low grade glioma, and 1 cavernous malformation. Toxicities were graded by the Radiation Therapy Oncology Group Acute/Late Radiation Morbidity Scoring Criteria. "Rare toxicities" were characterized as those reported in the scientific literature at an incidence of <5%. Median follow-up time was 16 months. Median dose to the tumor margin was 13.0 Gy (range, 12-21 Gy). Median size of tumor was 5.0 cm(3) (range, 0.14-7.8 cm(3)). Of the 14 patients with CVD, none experienced a Grade 3 or 4 toxicity or a toxicity characterized as rare. Of the 6 patients with MS, 3 experienced rare toxicities, and two of these were Grade 3 toxicities. Rare complications included a patient experiencing both communicating hydrocephalus and facial nerve palsy, as well as 2 additional patients with motor cranial nerve palsy. High-grade toxicities included the patient with an acoustic neuroma requiring ventriculoperitoneal shunt placement for obstructive hydrocephalus, and 1 patient with a facial nerve schwannoma who experienced permanent facial nerve palsy. Interval between radiosurgery and high-grade toxicities ranged from 1 week to 4 months. Our series suggests that patients with MS who receive GKRS may be at increased risk of rare and high-grade treatment-related toxicity. Given the time course of toxicity, treatment-related edema or demyelination represent potential mechanisms.

Dermoid cyst in the facial nerve—A unique diagnosis

Facial nerve paralysis in children may occur as a complication of infections, trauma, or rarely from benign or malignant tumors of the facial nerve. We present the first reported case of a dermoid tumor in the facial nerve causing facial paralysis in a child. Case report at a tertiary Children's Hospital. A 9-month-old was referred to our institution for evaluation of persistent, complete right sided facial paralysis three months after receiving a diagnosis of Bell's palsy. A workup at our institution including MRI and CT revealed marked widening of the facial canal in the mastoid segment consistent with facial nerve schwannoma or hemangioma. Surgical exploration via mastoidectomy and facial nerve decompression revealed keratinous material containing hair that had fully eroded the facial nerve, disrupting it completely. The entire tumor was removed along with the involved segment of facial nerve, and the missing facial nerve segment was cable grafted. Histological examination of the tumor confirmed a ruptured dermoid cyst in the facial nerve. Facial nerve tumors are rare causes of facial paralysis in children, accounting for fewer than 10% of cases of facial paralysis in the pediatric population. Dermoid cyst can occur throughout the head and neck region in children, but a dermoid tumor in the facial nerve has not been described in the literature prior to this report. This represents a new and uncommon diagnostic entity in the evaluation of facial nerve paralysis in children. Appropriate imaging studies and pathology slides will be reviewed.

Arachnoid cyst in the internal auditory canal causing fluctuating facial paresis in a child

A lesion restricted to the internal auditory canal (IAC) proves to be a vestibular schwannoma in its early natural history more than 90% of the time. While meningiomas and facial nerve schwannomas constitute most of the remaining pathologies in this region, there are few reports of rare lesions like cavernomas, haemangiomas, lipomas, epidermoids and arachnoid cysts (ACs) [9]. Literature reveals that the incidence of lesions limited to the IAC is lesser in the paediatric age group than in adults. In this first-of-its-kind report in indexed paediatric literature, we describe an arachnoid cyst in the IAC rendered singular by the fluctuant clinical course of the facial paresis that its biological behaviour had effected. In the previous two reports in children [16, 17], the ACs had presented with progressive cranial nerve dysfunction.

Facial Nerve Schwannoma Involving Middle Cranial Fossa: When the Unilateral Sensorineural Hearing Loss Guide to the Correct Diagnosis

The Facial Nerve Schwannoma is a rare tumor and it seldom involved the middle cranial fossa. Facial nerve schwannoma has various manifestations, including facial palsy but unfortunately facial nerve is very resistant to compression and often facial nerve paralysis or a facial weakness are not present. We present a case of giant facial nerve schwannoma involved the middle cranial fossa without facial nerve paralysis. In these cases the unilateral hearing loss (if present) guide to a correct diagnosis.

Schwannomas along Different Segments of Facial Nerve: Case Series with Review of Literature

ABSTRACTFacial nerve schwannomas are rare conditions which can mimic many other conditions. A series of patients with facial nerve schwannomas were treated in our department, all of whom had a delay in diagnosis resulting in a significant morbidity. This prompted us to present this rare case series of schwannomas along different segments of facial nerve and also review the literature on such tumors—the different presentations, work-up issues in management and rehabilitation. A wide text and PubMed English literature-based search was done on the existing literature on facial nerve schwannomas and the summary presented. Facial nerve schwannomas can have multiple clinical presentations with or without a facial paresis. Only a high degree of clinical suspicion and early imaging can lead to this diagnosis. An early diagnosis of facial nerve schwannoma is important as the morbidity associated with the condition as well as the surgery increases with the delay in diagnosis.