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Kang H, Ji SY, Kim C, Koo J, Song J, Choi BY, Hwang K, Han JH. Hearing preservation after stereotactic radiosurgery for sporadic intracanalicular vestibular schwannomas classified as Koos grade 1. Cancer Med 2024; 13:e6990. [PMID: 38348957 PMCID: PMC10839155 DOI: 10.1002/cam4.6990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 12/19/2023] [Accepted: 01/22/2024] [Indexed: 02/15/2024] Open
Abstract
INTRODUCTION The mechanism of hearing loss following stereotactic radiosurgery (SRS) for vestibular schwannomas (VSs) remains unclear. There is conflicting evidence regarding cochlear nerve damage by transient volume expansion of VSs after radiosurgery and radiation-induced cochlear damage. This study aimed to investigate whether there is a specific patient population that can achieve definite hearing preservation after SRS for VSs. METHODS A total of 37 consecutive patients with sporadic unilateral intracanalicular VSs and serviceable hearing (Gardner-Roberson [G-R] class I or II) were treated with SRS from 2009 to 2023. This is a retrospective study. Survival analysis with Cox regression for hearing deterioration was performed. RESULTS The median age was 55 years old. The median tumor volume was 0.089 cm3 , and the median marginal dose was 12.0 Gy. Nonserviceable hearing deterioration occurred in 9 patients (24.3%), with a median onset of 11.9 months after SRS. The actuarial rates of serviceable hearing preservation were 86%, 82%, and 70% at 1, 2, and 3 years after SRS, respectively. In a multivariate analysis, only baseline pure tone average > 30 dB increased the risk of nonserviceable hearing deterioration with significant hazard ratio. There were 13 patients with petit VSs whose tumor volume was smaller than 0.05 cm3 , and 11 of them were treated by a 4-mm single shot with a marginal dose of 12 Gy. None of the 13 patients had nonserviceable hearing deterioration. CONCLUSIONS Petit VSs that can be treated with 4-mm single or double shots with a marginal dose of 12 Gy may achieve hearing preservation after SRS.
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Affiliation(s)
- Ho Kang
- Department of NeurosurgerySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
| | - So Young Ji
- Department of NeurosurgerySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
| | - Chae‐Yong Kim
- Department of NeurosurgerySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
| | - Ja‐Won Koo
- Department of OtorhinolaryngologySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
| | - Jae‐Jin Song
- Department of OtorhinolaryngologySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
| | - Byung Yoon Choi
- Department of OtorhinolaryngologySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
| | - Kihwan Hwang
- Department of NeurosurgerySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
| | - Jung Ho Han
- Department of NeurosurgerySeoul National University Bundang Hospital, Seoul National University College of MedicineSeongnam‐siKorea
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Puataweepong P, Dhanachai M, Swangsilpa T, Sitathanee C, Ruangkanchanasetr R, Hansasuta A, Pairat K. Long-term clinical outcomes of stereotactic radiosurgery and hypofractionated stereotactic radiotherapy using the CyberKnife ® robotic radiosurgery system for vestibular schwannoma. Asia Pac J Clin Oncol 2021; 18:e247-e254. [PMID: 34310064 DOI: 10.1111/ajco.13592] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 03/04/2021] [Indexed: 11/30/2022]
Abstract
AIM The study aimed to evaluate the long-term clinical outcomes of patients with vestibular schwannoma (VS) treated with stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (HSRT) with frameless robotic whole-body radiosurgery system (CyberKnife® ). METHODS This retrospective analysis of prospectively collected data included 123 consecutive patients with VS treated at the Radiosurgery center, Ramathibodi Hospital, Bangkok, Thailand. SRS was recommended for patients with unserviceable hearing and Koos grade I-III tumors, and HSRT for patients with serviceable hearing or Koos grade III-IV tumors. Between March 2009 and December 2015, 23 patients (19%) were treated with SRS, whereas 100 (81%) received HSRT. The commonly used regimen was 12 Gy in one fraction for SRS and 18 Gy in three fractions for HSRT. RESULTS After a median follow-up of 72 months (range: 12-123 months), the 5-year and 8-year progression-free survival (PFS) rates for the whole cohort were 96% and 92%, respectively. The PFS was not significantly different between the SRS and HSRT groups (p = 0.23). Among 28 patients with serviceable hearing in the HSRT group, the 5-year and 8-year hearing preservation rates were 87% and 65%, respectively. The rate of nonauditory complications was 14%. Koos grade III/IV was a predictor of disease progression and was associated with nonauditory complications. CONCLUSION SRS and HSRT with the CyberKnife® system provided excellent long-term tumor control with a low rate of nonauditory complications. HSRT may result in acceptable hearing preservation rates.
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Affiliation(s)
- Putipun Puataweepong
- Radiation and Oncology Unit, Department of Radiology, Ramathibodi Hospital, Faculty of Medicine, Mahidol University, Bangkok, Thailand
| | - Mantana Dhanachai
- Radiation and Oncology Unit, Department of Radiology, Ramathibodi Hospital, Faculty of Medicine, Mahidol University, Bangkok, Thailand
| | - Thiti Swangsilpa
- Radiation and Oncology Unit, Department of Radiology, Ramathibodi Hospital, Faculty of Medicine, Mahidol University, Bangkok, Thailand
| | - Chomporn Sitathanee
- Radiation and Oncology Unit, Department of Radiology, Ramathibodi Hospital, Faculty of Medicine, Mahidol University, Bangkok, Thailand
| | - Rawee Ruangkanchanasetr
- Radiation and Oncology Unit, Department of Radiology, Ramathibodi Hospital, Faculty of Medicine, Mahidol University, Bangkok, Thailand
| | - Ake Hansasuta
- Department of Surgery, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Kumuthinee Pairat
- Radiosurgery Center, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
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Time-based Assessment of Hearing Preservation Rates After Microsurgical Resection of Vestibular Schwannomas: A Systematic Review. Otol Neurotol 2021; 41:679-685. [PMID: 32150025 DOI: 10.1097/mao.0000000000002598] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine short- and intermediate-term hearing preservation rates after microsurgical resection of vestibular schwannoma (VS). DATA SOURCES Systematic review of the Ovid, Cochrane, EMBASE, and Web of Science databases. STUDY SELECTION This study was restricted to full-text English-language articles detailing VS resection via the middle cranial fossa or retrosigmoid approaches. Documentation of pre- and posttreatment hearing outcomes with American Academy of Otolaryngology-Head and Neck Surgery, Gardner-Robertson, or word recognition score scales, as well as time to follow-up were required. Duplicate data sets, studies with >10% of patients with neurofibromatosis two, previous or nonsurgical VS treatment, case reports with <five patients, or studies detailing decompressive surgery were excluded. DATA EXTRACTION Two authors independently performed full-text reviews to determine study eligibility. Discrepancies were settled by consensus. "Class A/B, I/II" hearing was defined as AAO-HNS Class A or B, Gardner-Robertson Class 1 or 2, or PTA ≤ 50 dB with word recognition score ≥ 50% on audiogram. DATA SYNTHESIS Pooled estimates of preserved Class A/B, I/II hearing at last postoperative follow-up. CONCLUSIONS Of 1323 reports, 14 were utilized in analyses yielding data from 2,977 patients. Mean follow-up was 52.5 months (SD = 19.9). Class A/B, 1/2 hearing was preserved at last follow-up in 57% of patients. Meta-regression revealed that resection through the middle cranial fossa was associated with preservation of serviceable hearing. Moreover, when preserved in the immediate postoperative period, it seems to be stable over time.
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Cesme DH, Alkan A, Gultekin MA, Sari L, Alkan G, Seyithanoglu MH, Hatiboglu MA. Evaluation of Brainstem Subcortical Auditory Pathways with Diffusion Tensor Imaging After Gamma Knife Radiosurgery in Intracanalicular Vestibular Schwannoma. Medeni Med J 2021; 36:7-13. [PMID: 33828884 PMCID: PMC8020186 DOI: 10.5222/mmj.2021.15564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/04/2021] [Indexed: 12/05/2022] Open
Abstract
Objective To investigate changes in DTI (Diffusion Tensor Imaging) parameters in brainstem subcortical auditory pathways after Gamma Knife Radiosurgery (GKR) in patients with intracanalicular vestibular schwannoma (ICVS) and to analyze the relationship between tumor volume and ADC (apparent diffusion coefficient) and FA (fractional anisotropy) values. Method Seventeen patients with ICVS were evaluated before and after GKR. ADC and FA values of the lateral lemniscus (LL) and inferior colliculus (IC) and tumor volume were calculated. Patients who responded to GKR were classified as Group 1 and those who did not respond adequately as Group 2. The relationship between ADC and FA values and changes in tumor volume were analyzed. Results Tumor volume significantly decreased after GKR. ADC values obtained from the tumor increased after GKR (p:0.002). There was no significant difference in LL and IC before and after GKR in terms of FA and ADC values (n:17). There was a positive correlation between response to treatment and contralateral LL ADC values after GKR (p=0.005, r:0.652). There was a negative correlation between contralateral IC FA values after GKR and response to treatment (p=0.017, r: -0.568). There was a significant difference between Groups 1 and 2 in regards to contralateral LL ADC (p=0.03) and IC FA values (p=0.017). Conclusion Since the cochlear nerve and subcortical auditory pathways have low regeneration potential after nerve damage, ADC and FA changes in LL and IC may be explained with the presence of intracanalicular tumors prior to GKR. Since GKR does not cause additional damage to the subcortical auditory pathways at the brainstem level, we think that GKR is a noninvasive treatment method that can be used safely in patients with ICVS.
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Affiliation(s)
- Dilek Hacer Cesme
- Bezmialem Vakif University, Faculty of Medicine, Department of Radiology, Istanbul, Turkey
| | - Alpay Alkan
- Bezmialem Vakif University, Faculty of Medicine, Department of Radiology, Istanbul, Turkey
| | - Mehmet Ali Gultekin
- Bezmialem Vakif University, Faculty of Medicine, Department of Radiology, Istanbul, Turkey
| | - Lutfullah Sari
- Bezmialem Vakif University, Faculty of Medicine, Department of Radiology, Istanbul, Turkey
| | - Gokberk Alkan
- Abdurrahman Yurtaslan Oncology Training and Research Hospital, Department of Otorhinolaryngology, Ankara, Turkey
| | | | - Mustafa Aziz Hatiboglu
- Bezmialem Vakif University, Faculty of Medicine, Department of Neurosurgery, Istanbul, Turkey
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Cesme DH, Alkan A, Gultekin MA, Sari L, Alkan G, Kaya A, Mayadagli A, Akdur K, Uysal O, Hatiboglu MA. Diffusion Tensor Imaging Features of the Auditory Pathways in Patients With Vestibular Schwannoma After Gamma Knife Radiosurgery. Cureus 2021; 13:e14143. [PMID: 33927945 PMCID: PMC8075324 DOI: 10.7759/cureus.14143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Objective In this study, we aimed to investigate whether there is any change in diffusion tensor imaging (DTI) parameters in ipsilateral and contralateral auditory pathways after Gamma Knife radiosurgery (GKR) in patients with vestibular schwannoma (VS) and the relationship between radiosurgery variables. Methods Sixty-six patients were evaluated with MRI and DTI before and after GKR. The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured from the bilateral lateral lemniscus (LL), inferior colliculus (IC), medial geniculate body (MGB), and Heschl's gyrus (HG). Results There was no significant difference in ADC and FA values obtained from bilateral LL, IC, and MGB before and after radiosurgery. However, there was a significant difference between pretreatment and post-radiosurgery contralateral HG ADC values. The ADC values obtained from the contralateral HG and IC positively correlated with the duration after radiosurgery. As the duration after radiosurgery increases, the difference between the ADC values obtained from ipsilateral and contralateral HG also increases. Conclusion The high ADC values in the contralateral HG after radiosurgery may indicate microstructural alterations such as demyelination and axonal loss. Radiation exposure doses to the brainstem and cochlea are the most important factors that can cause microstructural damage to the auditory pathways. When planning radiosurgery, extreme care should be taken to prevent the harmful effects of radiation on the auditory pathways.
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Affiliation(s)
- Dilek H Cesme
- Department of Radiology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Alpay Alkan
- Department of Radiology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Mehmet Ali Gultekin
- Department of Radiology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Lutfullah Sari
- Department of Radiology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Gokberk Alkan
- Otorhinolaryngology, Abdurrahman Yurtaslan Oncology Training and Research Hospital, Ankara, TUR
| | - Ahmet Kaya
- Department of Radiology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Alpaslan Mayadagli
- Radiation Oncology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Kerime Akdur
- Radiation Oncology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Omer Uysal
- Biostatistics, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
| | - Mustafa A Hatiboglu
- Neurosurgery, Faculty of Medicine, Bezmialem Vakif University, Istanbul, TUR
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Farschtschi S, Mautner VF, McLean ACL, Schulz A, Friedrich RE, Rosahl SK. The Neurofibromatoses. DEUTSCHES ARZTEBLATT INTERNATIONAL 2020; 117:354-360. [PMID: 32657748 DOI: 10.3238/arztebl.2020.0354] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 04/18/2019] [Accepted: 03/20/2020] [Indexed: 01/10/2023]
Abstract
BACKGROUND Neurofibromatosis of types 1 and 2 (NF1, NF2) and schwannomatosis are the diseases that make up the neurofibromatosis spectrum. With respective incidences of 1 in 3000, 1 in 33 000, and 1 in 60 000 births, they form part of the group of rare tumor-suppressor syndromes. They give rise to a greater tumor burden for the nervous system than any other type of neoplastic disease. New approaches to symptomatic treatment are emerging. METHODS This review is based on articles retrieved by a selective literature search on the pathogenesis, diagnosis, and treatment of the neurofibromatoses. RESULTS NF1 and NF2 are monogenic diseases, while the genetics of schwannomatosis is complex. The three entities are clinically and pathophysiologically distinct. An important aspect of their tumor biology is the alternation of growth phases and growth pauses. Correlations between genotypes and phenotypes are variable, while new mutations and genetic mosaics are common. Ninety-nine percent of patients with NF1 have six or more café-au-lait spots by the age of 12 months; 90-95% of patients with NF2 develop bilateral vestibular schwannomas. In schwannomatosis, pain is the most prominent symptom; two-thirds of those affected develop spinal schwannomas. The severity and prognosis of these disorders are not closely correlated with the radiological findings; rather, neurologic deficits, malignant transformation, and psychosocial stress are of greater clinical importance. Advances in knowledge of pathophysiology have led to the development of targeted treatment approaches. Examples include the off-label treatment of vestibular schwannomas with bevacizumab and of plexiform neurofibromas with MEK inhibitors. CONCLUSION Patients with neurofibromatoses need individualized care. They should be treated in centers of expertise where interdisciplinary consultation is available and new types of pharmacotherapy can be provided.
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Affiliation(s)
- Said Farschtschi
- International Center for Neurofibromatoses (ICNF), Department of Neurology, University MedicalCenter Hamburg-Eppendorf
| | - Victor-Felix Mautner
- International Center for Neurofibromatoses (ICNF), Department of Neurology, University MedicalCenter Hamburg-Eppendorf
| | | | | | - Reinhard E Friedrich
- Department of Oromaxillofacial Surgery, University Medical Center Hamburg-Eppendorf
| | - Steffen K Rosahl
- Neurofibromatosis Center, Department of Neurosurgery, Helios Hospital Erfurt
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Prabhu V, Kondziolka D, Hill TC, Benjamin CG, Shinseki MS, Golfinos JG, Roland JT, Fatterpekar GM. Preserved Cochlear CISS Signal is a Predictor for Hearing Preservation in Patients Treated for Vestibular Schwannoma With Stereotactic Radiosurgery. Otol Neurotol 2018; 39:628-631. [PMID: 29561382 DOI: 10.1097/mao.0000000000001762] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Hearing preservation is a goal for many patients with vestibular schwannoma. We examined pretreatment magnetic resonance imaging (MRI) and posttreatment hearing outcome after stereotactic radiosurgery. METHODS From 2004 to 2014, a cohort of 125 consecutive patients with vestibular schwannoma (VS) treated via stereotactic radiosurgery (SRS) were retrospectively reviewed. MRIs containing three-dimensional constructive interference in steady state or equivalent within 1 year before treatment were classified by two radiologists for pretreatment characteristics. "Good" hearing was defined as American Academy of Otolaryngology-Head and Neck Surgery class A. Poor hearing outcome was defined as loss of good pretreatment hearing after stereotactic radiosurgery. RESULTS Sixty-one patients met criteria for inclusion. Most had tumors in the distal internal auditory canal (55%), separated from the brainstem (63%), oval shape (64%) without cysts (86%), and median volume of 0.85 ± 0.55 cm. Pretreatment audiograms were performed a median of 108 ± 173 days before stereotactic radiosurgery; 38% had good pretreatment hearing. Smaller tumor volume (p < 0.005) was the only variable associated with good pretreatment hearing. 49 (80%) patients had posttreatment audiometry, with median follow-up of 197 ± 247 days. Asymmetrically decreased pretreatment cochlear CISS signal on the side of the VS was the only variable associated with poor hearing outcome (p = 0.001). Inter-rater agreement on cochlear three-dimensional constructive interference in steady state preservation was 91%. CONCLUSIONS Decreased cochlear CISS signal may indicate a tumor's association with the cochlear neurovascular bundle, influencing endolymph protein concentration and creating an inability to preserve hearing. This important MRI characteristic can influence planning, counseling, and patient selection for vestibular schwannoma treatment.
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Affiliation(s)
| | | | | | | | | | | | - J Thomas Roland
- Department of Otolaryngology, NYU School of Medicine, New York, New York
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Rosahl S, Bohr C, Lell M, Hamm K, Iro H. Diagnostics and therapy of vestibular schwannomas - an interdisciplinary challenge. GMS CURRENT TOPICS IN OTORHINOLARYNGOLOGY, HEAD AND NECK SURGERY 2017; 16:Doc03. [PMID: 29279723 PMCID: PMC5738934 DOI: 10.3205/cto000142] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Vestibular schwannomas (VS) expand slowly in the internal auditory canal, in the cerebellopontine angle, inside the cochlear and the labyrinth. Larger tumors can displace and compress the brainstem. With an annual incidence of 1:100,000 vestibular schwannoma represent 6-7% of all intracranial tumors. In the cerebellopontine angle they are by far the most neoplasm with 90% of all lesions located in this region. Magnetic resonance imaging (MRI), audiometry, and vestibular diagnostics are the mainstays of the clinical workup for patients harboring tumors. The first part of this paper delivers an overview of tumor stages, the most common grading scales for facial nerve function and hearing as well as a short introduction to the examination of vestibular function. Upholding or improving quality of life is the central concern in counseling and treating a patient with vestibular schwannoma. Preservation of neuronal function is essential and the management options - watchful waiting, microsurgery and stereotactic radiation - should be custom-tailored to the individual situation of the patient. Continuing interdisciplinary exchange is important to monitor treatment quality and to improve treatment results. Recently, several articles and reviews have been published on the topic of vestibular schwannoma. On the occasion of the 88th annual meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck surgery a special volume of the journal "HNO" will be printed. Hence this presentation has been designed to deviate from the traditional standard which commonly consists of a pure literature review. The current paper was conceptually woven around a series of interdisciplinary cases that outline examples for every stage of the disease that show characteristic results for management options to date. Systematic clinical decision pathways have been deduced from our experience and from results reported in the literature. These pathways are graphically outlined after the case presentations. Important criteria for decision making are size and growth rate of the tumor, hearing of the patient and the probability of total tumor resection with preservation of hearing and facial nerve function, age and comorbidity of the patient, best possible control of vertigo and tinnitus and last but not least the patient's preference and choice. In addition to this, the experience and the results of a given center with each treatment modality will figure in the decision making process. We will discuss findings that are reported in the literature regarding facial nerve function, hearing, vertigo, tinnitus, and headache and reflect on recent studies on their influence on the patient's quality of life. Vertigo plays an essential role in this framework since it is an independent predictor of quality of life and a patient's dependence on social welfare. Pathognomonic bilateral vestibular schwannomas that occur in patients suffering from neurofibromatosis typ-2 (NF2) differ from spontaneous unilateral tumors in their biologic behavior. Treatment of neurofibromatosis type-2 patients requires a multidisciplinary team, especially because of the multitude of separate intracranial and spinal lesions. Off-label chemotherapy with Bevacizumab can stabilize tumor size of vestibular schwannomas and even improve hearing over longer periods of time. Hearing rehabilitation in NF2 patients can be achieved with cochlear and auditory brainstem implants.
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Affiliation(s)
- Steffen Rosahl
- Department of Neurosurgery, Helios Hospital of Erfurt, Germany
| | - Christopher Bohr
- Department of Otolaryngology, University Hospital of Erlangen, Germany
| | - Michael Lell
- Institute for Radiology and Nuclear Medicine, Hospital of Nuremberg, Germany
| | - Klaus Hamm
- Cyberknife Center of Central Germany, Erfurt, Germany
| | - Heinrich Iro
- Department of Neurosurgery, Helios Hospital of Erfurt, Germany
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