Incidence and Risk Factors of Delayed Facial Palsy After Vestibular Schwannoma Resection.

BACKGROUND: Preservation of facial nerve function following vestibular schwannoma surgery is a high priority. Even those patients with normal to near-normal function in the early postoperative period remain at risk for delayed facial palsy (DFP). OBJECTIVE: To evaluate the incidence and prognosis of DFP and to identify risk factors for its occurrence. METHODS: A retrospective cohort study of 489 patients who underwent vestibular schwannoma resection at our institution between 2000 and 2014. Delayed facial palsy was defined as deterioration in facial function of at least 2 House-Brackmann (HB) grades between postoperative days 5 to 30. Only patients with a HB grade of I to III by postoperative day 5 were eligible for study inclusion. RESULTS: One hundred twenty-one patients with HB grade IV to VI facial weakness at postoperative day 5 were excluded from analysis. Of the remaining 368, 60 (16%) patients developed DFP (mean 12 days postoperatively, range: 5-25 days). All patients recovered function to HB grade I to II by a mean of 33 days (range: 7-86 days). Patients that developed DFP had higher rates of gross total resections (83% vs 71%, P = .05) and retrosigmoid approaches (72% vs 52%, P < .01). There was no difference in recovery time between patients who received treatment with steroids, steroids with antivirals, or no treatment at all (P = .530). CONCLUSION: Patients with a gross total tumor resection or undergoing a retrosigmoid approach may be at higher risk of DFP. The prognosis is favorable, with patients likely recovering to normal or near-normal facial function within 1 month of onset.

Long-term quality of life in patients with vestibular schwannoma: an international multicenter cross-sectional study comparing microsurgery, stereotactic radiosurgery, observation, and nontumor controls.

OBJECT: The optimal treatment for sporadic vestibular schwannoma (VS) is highly controversial. To date, the majority of studies comparing treatment modalities have focused on a narrow scope of technical outcomes including facial function, hearing status, and tumor control. Very few publications have investigated health-related quality of life (HRQOL) differences between individual treatment groups, and none have used a disease-specific HRQOL instrument. METHODS: All patients with sporadic small- to medium-sized VSs who underwent primary microsurgery, stereotactic radiosurgery (SRS), or observation between 1998 and 2008 were identified. Subjects were surveyed via postal questionnaire using the 36-Item Short Form Health Survey (SF-36), the 10-item Patient-Reported Outcomes Measurement Information System short form (PROMIS-10), the Glasgow Benefit Inventory (GBI), and the Penn Acoustic Neuroma Quality-of-Life (PANQOL) scale. Additionally, a pool of general population adults was surveyed, providing a nontumor control group for comparison. RESULTS: A total of 642 respondents were analyzed. The overall response rate for patients with VS was 79%, and the mean time interval between treatment and survey was 7.7 years. Using multivariate regression, there were no statistically significant differences between management groups with respect to the PROMIS-10 physical or mental health dimensions, the SF-36 Physical or Mental Component Summary scores, or the PANQOL general, anxiety, hearing, or energy subdomains. Patients who underwent SRS or observation reported a better total PANQOL score and higher PANQOL facial, balance, and pain subdomain scores than the microsurgical cohort (p < 0.02). The differences in scores between the nontumor control group and patients with VS were greater than differences observed between individual treatment groups for the majority of measures. CONCLUSIONS: The differences in HRQOL outcomes following SRS, observation, and microsurgery for VS are small. Notably, the diagnosis of VS rather than treatment strategy most significantly impacts quality of life. Understanding that a large number of VSs do not grow following discovery, and that intervention does not confer a long-term HRQOL advantage, small- and medium-sized VS should be initially observed, while intervention should be reserved for patients with unequivocal tumor growth or intractable symptoms that are amenable to treatment. Future studies assessing HRQOL in VS patients should prioritize use of validated disease-specific measures, such as the PANQOL, given the significant limitations of generic instruments in distinguishing between treatment groups and tumor versus nontumor subjects.

The significance of intraoperative electromyographic "lateral spread" in predicting outcome of microvascular decompression for hemifacial spasm.

OBJECTIVES: During microvascular decompression (MVD) of the facial nerve for hemifacial spasm (HFS), an abnormal muscle response can be recorded upon stimulation of the facial nerve, also known as the lateral spread response. This response may vanish after MVD and has been associated with a successful outcome. The purpose of this study was to determine if resolution of lateral spread correlated with the elimination of HFS in a single surgeon's experience. Design and SETTING: (1) Retrospective analysis of 38 patients undergoing MVD with intraoperative electromyography for HFS. (2) Meta-analysis of studies from the literature. MAIN OUTCOME MEASURE: Presence or absence of HFS and any complications. RESULTS: Lateral spread response was seen in 36 patients; 20 patients had full resolution. Of these, 15 patients became HFS free, and 5 five patients still had some degree of HFS. Sixteen patients had a persistent lateral spread response despite a technically successful MVD; 11 of these became spasm free, and 5 still suffered from some degree of facial twitching. Analyzing 16 studies reporting a total of 1301 patients, a significant correlation (p < 0.0001) between response cessation and resolution of HFS was found. CONCLUSION: The role of monitoring lateral spread response as a predictor for clinical outcome is limited.

Herpes simplex meningitis after removal of a vestibular schwannoma: case report and review of the literature.

OBJECTIVE: We present a case of postoperative herpes simplex type 1 viral meningitis after retrosigmoid craniotomy and uncomplicated removal of a vestibular schwannoma. This is a very rare complication that can mimic aseptic meningitis and could lead to devastating consequences for the patient, if unrecognized. PATIENT: A healthy 49-year-old woman underwent retrosigmoid craniotomy and resection of a 2.4-cm vestibular schwannoma. She developed worsening headache and low-grade fever on postoperative Day 10 and underwent lumbar puncture showing a lymphocyte predominant pleocytosis. Polymerase chain reaction was positive for herpes simplex type 1 virus; bacterial cultures were negative. The patient subsequently developed a pseudomeningocele and mild hydrocephalus. INTERVENTION: The patient was readmitted to the hospital, started on corticosteroids, and a lumbar drain was placed. She completed a 14-day course of antiviral therapy (4 d intravenous as an inpatient and 10 d oral outpatient therapy). RESULTS: At 1 month follow-up, she was completely asymptomatic, and her pseudomeningocele had resolved. CONCLUSION: The diagnosis of herpes simplex viral meningitis should be suspected in clinical cases of postsurgical meningitis with a lymphocyte predominant pleocytosis and negative bacterial cultures. Antiviral therapy should be initiated immediately after confirmatory polymerase chain reaction testing to avoid potential long-term sequelae of a herpes simplex infection of the central nervous system.

Magnetic resonance imaging surveillance following vestibular schwannoma resection.

OBJECTIVES/HYPOTHESIS: To describe the incidence, pattern, and course of postoperative enhancement within the operative bed using serial gadolinium-enhanced magnetic resonance imaging (MRI) following vestibular schwannoma (VS) resection and to identify clinical and radiologic variables associated with recurrence. STUDY DESIGN: Retrospective cohort study. METHODS: All patients who underwent microsurgical resection of VS between January 2000 and January 2010 at a single tertiary referral center were reviewed. Postoperative enhancement patterns were characterized on serial MRI studies. Clinical follow-up and outcomes were recorded. RESULTS: During the last 10 years, 350 patients underwent microsurgical VS resection, and of these, 203 patients met study criteria (mean radiologic follow-up, 3.5 years). A total of 144 patients underwent gross total resection (GTR), 32 received near-total resection (NTR), and the remaining 27 underwent subtotal resection (STR); 98.5% of patients demonstrated enhancement within the operative bed following resection (58.5% linear, 41.5% nodular). Stable enhancement patterns were seen in 24.5% of patients, regression in 66.0%, and resolution in only 3.5% of patients on the most recent postoperative MRI. Twelve patients recurred a mean of 3.0 years following surgery. The average maximum linear diameter growth rate among recurrent tumors was 2.3 mm per year. Those receiving STR were more than nine times more likely to experience recurrence compared to those undergoing NTR or GTR (P < .001). Nodular enhancement on the initial postoperative MRI was associated with a 16-fold increased risk for future recurrence compared to those with linear patterns (P = .008). Among those with nodular enhancement on baseline postoperative MRI, a maximum linear diameter of ≥ 15 mm or volume of ≥ 0.4 cm(3) was associated with an approximate five-fold increased risk for future growth (P < .02). CONCLUSIONS: Persistent nonspecific radiologic enhancement within the postoperative field is common, making the diagnosis of tumor recurrence challenging. Factors including completeness of resection and baseline postoperative MRI findings provide valuable information regarding risk for recurrence, which may assist the clinician in determining an appropriate postoperative MRI surveillance schedule. Future studies using standardized terminology and consistent study metrics are needed to further refine surveillance recommendations.