Facial nerve injury in acoustic neuroma (vestibular schwannoma) surgery: etiology and prevention.
ABSTRACT Facial nerve injury associated with acoustic neuroma surgery has declined in incidence but remains a clinical concern. A retrospective analysis of 611 patients surgically treated for acoustic neuroma between 1973 and 1994 was undertaken to understand patterns of facial nerve injury more clearly and to identify factors that influence facial nerve outcome. Anatomical preservation of the facial nerve was achieved in 596 patients (97.5%). In the immediate postoperative period, 62.1% of patients displayed normal or near-normal facial nerve function (House-Brackmann Grade 1 or 2). This number rose to 85.3% of patients at 6 months after surgery and by 1 year, 89.7% of patients who had undergone acoustic neuroma surgery demonstrated normal or near-normal facial nerve function. The surgical approach appeared to have no effect on the incidence of facial nerve injury. Poor facial nerve outcome (House-Brackmann Grade 5 or 6) was seen in 1.58% of patients treated via the suboccipital approach and in 2.6% of patients treated via the translabyrinthine approach. When facial nerve outcome was examined with respect to tumor size, there clearly was an increased incidence of facial nerve palsy seen in the immediate postoperative period in cases of larger tumors: 60.8% of patients with tumors smaller than 2.5 cm had normal facial nerve function, whereas only 37.5% of patients with tumors larger than 4 cm had normal function. This difference was less pronounced, however, 6 months after surgery, when 92.1% of patients with tumors smaller than 2.5 cm had normal or near normal facial function, versus 75% of patients with tumors larger than 4 cm. The etiology of facial nerve injury is discussed with emphasis on the pathophysiology of facial nerve palsy. In addition, on the basis of the authors' experience with these complex tumors, techniques of preventing facial nerve injury are discussed.
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ABSTRACT: For large (≥30 mm) or giant (≥40 mm) vestibular schwannomas (VSs) for which microsurgical removal is the main treatment option, complete tumour resection and the preservation of acceptable facial nerve function can be safely and successfully achieved via the retrosigmoid approach. We performed a meta-analysis to provide a reliable estimate of functional outcome and postoperative complications for patients treated surgically for large VSs. We conducted a comprehensive search in Pubmed, Embase and the Chinese National Knowledge Infrastructure (CNKI) databases to identify publications that included only patients in whom the VSs were >3.0 cm in maximal diameter and microsurgically removed by a retrosigmoid approach. Pooled estimates of proportions with corresponding 95 % confidence intervals were calculated using the Freeman-Tukey double arcsine transformation. This meta-analysis revealed that the pooled proportion of gross total resections was 79.1 % (95 % CI, 64.2-90.8 %; I (2) = 95.4 %). By combining microsurgical techniques with continuous electrophysiological monitoring, the anatomical preservation of the facial nerve at the end of surgery was achieved in 88.8 % (95 % CI, 83.6-93.2 %; I (2) = 76.1 %) of the patients. The pooled proportion of good postoperative facial nerve function (House-Brackmann (HB) grades I-II) was 62.9 % (95 % CI, 50.0-74.9 %; I (2) = 91.1 %). Cerebrospinal fluid leakage was reported in 7.8 % (95 % CI, 4.8-11.4 %; I (2) = 49.8 %) of the patients. The mortality rate was 0.87 % (95 % CI, 0.22-1.78 %; I (2) = 4.9 %). Our meta-analysis revealed that for large VSs, very favourable results can be obtained using the retrosigmoid approach with minimal mortality, especially with respect to anatomical and functional facial nerve preservation.Neurosurgical Review 06/2013; · 1.97 Impact Factor
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ABSTRACT: Vestibular schwannomas (VS) or acoustic neuromas are benign tumors arising from Schwann cells of the vestibular branch of the eighth cranial nerve. The tumor was first described 1910 by Henschen, who provided evidence that it originates from the Schwann cells. Nevertheless, the term acoustic neuroma was commonly used. The National Institute of Health decided in 1992 in a Consensus Development Conference: “The term vestibular schannoma is preferred over acoustic neuroma as these tumors are composed of Schwann cells and typically involve the vestibular rather than the acoustic division of the eighth cranial nerve.” Therefore, we will use the term of VS, although acoustic neuroma is still more common in the literature.Otolaryngologic Clinics of North America 04/2012; 45(2):xiii-xv. · 1.46 Impact Factor
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ABSTRACT: OBJECTIVES/HYPOTHESIS: Evaluation of long-term patient-perceived functional outcomes and quality of life (QOL) related to communication and eating with an emphasis on voice, speech production, and swallowing after cerebello-pontine angle (CPA) surgery. STUDY DESIGN: Prospective cross-sectional study. METHODS: The MD Anderson Dysphagia Inventory (MDADI), Voice Handicap Index (VHI), and Facial Clinimetric Evaluation (FaCE) surveys were distributed to patients who underwent CPA surgery between January 2008 and December 2010. Immediate postoperative cranial nerve function extracted from medical records was compared to long-term patient-perceived function and associated QOL. RESULTS: There was a 61% response rate with a mean postoperative period of 31.6 months (range 15-49). The presence of facial palsy in the postoperative period and the corresponding House-Brackmann (H-B) score were the strongest predictors of patient-perceived long-term function and QOL in all three domains (P <.005). Postoperative vagal palsy by comparison was not associated with long-term disturbance of voice or speech function. Postoperative dysphagia had a particularly large association with perceived long-term facial function and related QOL (P <.0005), with a smaller but significant impact on perceived swallow outcome (P <.05). After adjusting for other variables, the postoperative H-B score remained a significant predictor of perceived long-term facial and voice function and related QOL. CONCLUSIONS: Patients with severe facial dysfunction following surgery to the CPA are at increased risk for long-term self-reported difficulties with communication and eating, even with improvement of vagal function. Speech and swallow therapy should therefore be provided to these patients whether or not they also have pharyngeal dysphagia or voice disturbance. LEVEL OF EVIDENCE: 2b. Laryngoscope, 2013.The Laryngoscope 06/2013; · 1.98 Impact Factor