Local experience with radiosurgery for vestibular schwannomas and recommendations for management (original) (raw)

Radiosurgery for Vestibular Schwannomas

Journal of the Chinese Medical Association, 2005

Background: Radiosurgery has been established as an important alternative to microsurgery. We report our experience with radiosurgery for tumor control and the complications of unilateral vestibular schwannomas. Methods: We reviewed our early experience regarding clinical presentation, management and outcomes in 45 patients with acoustic schwannomas who underwent gamma knife stereotactic radiosurgery. The median follow-up period was 25 months (range, 6-48 months). Thirteen patients had undergone 1 or more previous resections before radiosurgery; 32 underwent radiosurgery as the first procedure. Median tumor volume was 4.5 mL (range, 0.5-30.0), and median radiotherapy dose was 11.5 Gy (range, 10.5-14.0 Gy). Results: Tumor control was achieved in 43 patients (95.6%). Loss of central contrast enhancement was a characteristic change and was noted in 29 patients (64.4%). Reduction in tumor size was shown in 15 patients (33.3%). Thirteen patients (28.9%) had good or serviceable hearing preoperatively, and in all of these, the preoperative status was retained immediately after radiosurgery. At follow-up, however, 10 patients (76.9%) had preserved hearing and 3 (23.1%) had reduced hearing on the treated side. Hearing in 1 patient that was not serviceable preoperatively later improved to a serviceable level. No patients had delayed facial palsy or lower cranial nerve dysfunction, but one had delayed trigeminal sensory loss. Conclusion: Radiosurgery achieved a high tumor control rate and a relatively low post-radiosurgical complication rate for acoustic neuromas. [

Hearing preservation after stereotactic radiosurgery for vestibular schwannoma: A systematic review

Journal of Clinical Neuroscience, 2009

Radiosurgery has evolved into an effective alternative to microsurgical resection in the treatment of patients with vestibular schwannoma. We performed a systematic analysis of the literature in English on the radiosurgical treatment of vestibular schwannoma patients. A total of 254 published studies reported assessable and quantifiable outcome data of patients undergoing radiosurgery for vestibular schwannomas. American Association of Otolaryngology-Head and Neck Surgery (AAO-HNS) class A or B and Gardner-Robertson (GR) classification I or II were defined as having preserved hearing. A total of 5825 patients (74 articles) met our inclusion criteria. Practitioners who delivered an average dose of 612.5 Gy as the marginal dose reported having a higher hearing preservation rate (612.5 Gy = 59% vs. >12.5 Gy = 53%, p = 0.0285). Age of the patient was not a significant prognostic factor for hearing preservation rates (<65 years = 58% vs. >65 years = 62%; p = 0.4317). The average overall follow-up was 41.2 months. Our data suggest that an overall hearing preservation rate of about 57% can be expected after radiosurgical treatment, and patients treated with 612.5 Gy were more likely to have preserved hearing.

Gamma Knife radiosurgery for vestibular schwannoma: clinical results at long-term follow-up in a series of 379 patients

Journal of neurosurgery, 2014

Since the 1990 s, Gamma Knife radiosurgery (GKRS) has become the first-line treatment option for small- to medium-size vestibular schwannomas (VSs), especially in patients without mass effect-related symptoms and with functional hearing. The aim of this study was to assess the safety and efficacy of GKRS, in terms of tumor control, hearing preservation, and complications, in a series of 379 consecutive patients treated for VS. Of 523 patients treated at the authors' institution for VS between 2001 and 2010, the authors included 379 who underwent GKRS as the primary treatment. These patients were not affected by Type 2 neurofibromatosis and had clinical follow-up of at least 36 months. Clinical follow-up (mean and median 75.7 and 69.5 months, respectively) was performed for all patients, whereas audiometric and quantitative radiological follow-up examinations were obtained for only 153 and 219 patients, respectively. The patients' ages ranged from 23 to 85 years (mean 59 year...

Hearing outcomes between multi-session and single-session radiosurgery for vestibular schwannoma: a single center study

Translational Cancer Research, 2018

Background: Hearing preservation rate after Gamma Knife radiosurgery (GKRS) for vestibular schwannoma (VS) remains low. The aim of this study was to study hearing outcomes between multisession and single session GKRS in patients with VS and determine prognostic factors associated with hearing preservation. Methods: A retrospective analysis of 561 consecutive patients with VS subjected to multisession (74 patients) or single session (487 patients) GKRS (from June 2011 to April 2015) was performed. Propensity score matching (PSM) based on patient age, gender, tumor volume and pre-GKRS hearing was used to compare the two groups. The tumor control rate and complications were evaluated, especially hearing preservation and its prognostic factors. Results: According to PSM, 29 patients from each group with similar characteristics were selected for the study. Patients' age, tumor volume, pre-GKRS pure tone average (PTA) and radiographic follow-up period were not significantly different between the two groups (P>0.05). The tumor control rate was 75.9% for the multisession group compared with 62.1% for the single session group (P=0.1142); 20 patients had a less than 20 dB change in PTA in multisession group, with the hearing preservation rate of 69.0% (20/29) compared with 65.5% (19/29) in single session group (P=0.08). Multivariate analysis revealed that linear internal auditory canal (IAC) length was the only significant predictor of hearing loss in the multisession group. At last follow-up, one patient complaining of sudden hearing loss was diagnosed with tumor bleeding 12 months after multisession GKRS. One patient from multisession group and two patients from single session group suffered from temporal facial numbness. Facial spasm developed in one patient after multisession GKRS. Conclusions: Our results supported that multisession GKRS could be an effective and safe treatment option for VS compared to single session GKRS. The hearing preservation rate after multisession GKRS was not superior to single session radiosurgery in our short-term follow-up study. However, patients with longer IAC length may benefit from multisession strategy in terms of hearing preservation.

Adults diagnosed with vestibular schwannomas and treated with stereotactic radiosurgery: a scoping review protocol

2021

Review question / Objective: This review aims to catalogue and collate information on outcome measures, study designs, and dose-related changes in hearing following stereotactic radiosurgery for adults diagnosed with sporadic Vestibular Schwannoma. Study designs to be included: Any peer-reviewed primary research publications will be eligible for inclusion. Information sources: Electronic databases. The following databases will be systematically searched to identify relevant studies: PubMed, PsycINFO, EMBASE, EMCare, Web of Science and Cochrane Library.

Outcomes After Treatment of Vestibular Schwannoma by 2 Different Modalities; Microsurgical and Radiosurgical Techniques

2015

Background The choice between microsurgery and radiosurgery for treatment of vestibular schwannoma (VS) is debatable. There are a lot of treatment schedules, but the widely accepted is to treat tumors larger than 2.5 cm surgically, while tumors less than 2.5 cm could be offered the radiosurgical treatment. The aim of this work was to assess efficacy and safety of surgery and radiosurgery in treatment of vestibular schwannoma. Methods The study was performed as a retrospective evaluation of 70 patients who had undergone vestibular schwannoma treatment during the period between June 2004 and June 2010. Patients with follow up less than one year and those subjected to previous vestibular schwannoma treatment were excluded from the study. The patients were classified into two groups; surgery group included 20 patients and radiosurgery groups included 50 patients. Patient records, treatment reports, and follow-up data were analyzed. The main outcome measures were magnetic resonance imagi...

Stereotactic radiosurgery for vestibular schwannoma: International Stereotactic Radiosurgery Society (ISRS) Practice Guideline

Journal of radiosurgery and SBRT, 2017

Objectives The aim of this systematic review was to develop International Stereotactic Radiosurgery Society (ISRS) consensus guideline statements for vestibular schwannoma. Methods A systematic review of the literature was performed up to April 2015. Results A total of 55 full-text articles were included in the analysis. All studies were retrospective, except for 2 prospective quality of life studies. Five-year tumour control rates with Gamma Knife radiosurgery (RS), single fraction linac RS, or fractionated (either hypofractionated or conventional fractionation) stereotactic radiation therapy (FSRT) were similar at 81-100%. The single fraction RS series (linac or Gamma Knife) with tumour marginal doses between 12 and 14 Gy revealed 5-year tumour control rates of 90-99%, hearing preservation rates of 41-79%, facial nerve preservation rates of 95-100% and trigeminal preservation rates of 79-99%.There were 6 non-randomized studies comparing single fraction RS versus FSRT. There was no...

Analysis of risk factors associated with radiosurgery for vestibular schwannoma

Journal of Neurosurgery, 2001

Object. The aim of this study was to identify factors associated with delayed cranial neuropathy following radiosurgery for vestibular schwannoma (VS or acoustic neuroma) and to determine how such factors may be manipulated to minimize the incidence of radiosurgical complications while maintaining high rates of tumor control. Methods. From July 1988 to June 1998, 149 cases of VS were treated using linear accelerator radiosurgery at the University of Florida. In each of these cases, the patient's tumor and brainstem were contoured in 1-mm slices on the original radiosurgical targeting images. Resulting tumor and brainstem volumes were coupled with the original radiosurgery plans to generate dose—volume histograms. Various tumor dimensions were also measured to estimate the length of cranial nerve that would be irradiated. Patient follow-up data, including evidence of cranial neuropathy and radiographic tumor control, were obtained from a prospectively maintained, computerized dat...

Stereotactic Radiosurgery versus Natural History in Patients with Growing Vestibular Schwannomas

Journal of Neurological Surgery Part B: Skull Base, 2015

Objective To describe our experience with stereotactic radiosurgery and its efficacy on growing tumors, and then to compare this result with the natural history of a similar cohort of non-radiation-treated lesions. Study Design A retrospective chart review and cohort comparison. Methods The long-term control rates of patients having undergone radiosurgery were collected and calculated, and this population was then compared with a group of untreated patients from the same period of time with growing lesions. Results A total of 61 patients with growing vestibular schwannomas treated with radiosurgery were included. After a mean of 160 months, we observed a control rate of 85.2%. When compared with a group of 36 patients with growing tumors who were yet to receive treatment (previously published), we found a corrected control rate or relative risk reduction of only 76.8%. Conclusion Radiosurgery for growing vestibular schwannomas is less effective than previously reported in unselected series. Although radiosurgery still has a role in managing this disease, consideration should be given to the actual efficacy that may be calculated when the natural history is known. We hope other centers will similarly report their experience on this cohort of patients.

Fractionated Stereotactic Radiosurgery and Preservation of Hearing in Patients with Vestibular Schwannoma: A Preliminary Report

Neurosurgery, 1999

OBJECTIVE: Microsurgery and stereotactic radiosurgery (SRS) for vestibular schwannomas are associated with a relatively high incidence of sensorineural hearing loss. A prospective trial of fractionated SRS was undertaken in an attempt to preserve hearing and minimize incidental cranial nerve injury. METHODS: Thirty-three patients with vestibular schwannomas were treated with 2100 cGy in three fractions during a 24-hour period using conventional frame-based linear accelerator radiosurgery. The median tumor diameter was 20 mm (range, 7-42 mm). Baseline and follow-up evaluations included audiometry and contrast-enhanced magnetic resonance imaging. End points were tumor progression, preservation of serviceable hearing, and treatment-related complications. RESULTS: Thirty-one patients (32 tumors) were assessable for tumor progression and treatment-related complications and 21 patients for preservation of serviceable hearing, with a median follow-up interval of 2 years (range, 0.5-4.0 yr). Tumor regression or stabilization was documented in 30 patients (97%) and tumor progression in 1 (3%). The patient with tumor progression remains asymptomatic and has not required surgical intervention. Five patients (16%) developed trigeminal nerve injury at a median of 6 months (range, 4-12 mo) after SRS; two of these patients had preexisting trigeminal neuropathy. One patient (3%) developed facial nerve injury (House-Brackmann Class 3) 7 months after SRS. Preservation of useful hearing (Gardner-Robertson Class 1-2) was 77% at 2 years. All patients with pretreatment Gardner-Robertson Class 1 to 2 hearing maintained serviceable (Class 1-3) hearing as of their last follow-up examination. CONCLUSION: Three-fraction SRS with a conventional stereotactic frame is feasible and well tolerated in the treatment of acoustic neuroma. This study demonstrates a high rate of hearing preservation and few treatmentrelated complications among a relatively high-risk patient cohort (tumors >15 mm or neurofibromatosis Type 2). Longer follow-up will be required to assess the durability of tumor control. (Neurosurgery 45:1299(Neurosurgery 45: -1307(Neurosurgery 45: , 1999