Gamma Knife Stereotactic Radiosurgery (GKS) for the treatment of Vestibular Schwannomas (VS)

Introduction. Vestibular schwannomas (VS) or acoustic neuromas (AN) (as they are known to neurosurgeons) are benign tumors which originate at the junction between central nervous system myelin and peripheral nervous system myelin – an area known as the Obersteiner-Redlich area. Acoustic neuromas represent a special pathologic entity for neurosurgeons due to their important symptoms which need to be adressed as soon as possible and due to the secondary disfunctions which may appear if the tumors are not treated appropriately. Materials and methods. The study below presents the experience of the authors regarding the use of stereotactic radiosurgery for the treatment of acoustic neuromas. The authors focus on a population of 231 patients diagnosed and treated for VS over a period of 10 years at the „Bagdasar-Arseni“ University Hospital in Bucharest. This study compares the impact of Gamma Knife Surgery when performed alone or in association with open microneurosurgery. The authors assessed patients with tumors ranging between 0.25 and 14 cm3 in volume. Gamma Knife Surgery is used successfully to treat VS, both independantly or in association with open microsurgery. Results. The major complications of the treatment are represented by lack of response to treatment (less than 1% of patients) and cerebral edema (16.4% of patients). Conclusions. Given its multiple advantages, stereotactic radiosurgery is right now the tip of the spear regarding the therapeutical means available for VS. When the tumors met in daily practice are larger than the therapeutical resources of the devices used for Gamma Knife Surgery an open microsurgical approach may be attempted followed by stereotactic iradiation of the remnant tumor. Given the large number of successes reported in the literature and the small number of complications but also the ever progressing technology used to improve Gamma Knife devices, the authors consider stereotactic radiosurgery to be a very good solution for the treatment of VS. Furthermore, the improvement potential this technique has grants it the potential to improve standard of treatment for acoustic neuromas and the quality of life in patients with this disease.

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Gamma Knife Stereotactic Radiosurgery (GKS) for the treatment of meningiomas – a study of 550 cases

Romanian Medical Journal ◽

10.37897/rmj.2015.2.9 ◽

2015 ◽

Vol 62 (2) ◽

pp. 130-134

Author(s):

Radu Perin ◽

◽

Rodica Stempurszki ◽

Vasile Ciubotaru ◽

Ligia Tataranu ◽

...

Keyword(s):

Gamma Knife ◽

Gamma Knife Radiosurgery ◽

Daily Practice ◽

University Hospital ◽

Response To Treatment ◽

Benign Tumors ◽

Long Time ◽

Remnant Tumor ◽

Gamma Knife Stereotactic Radiosurgery ◽

The Impact

Introduction. Meningiomas are benign tumors which originate from the cells of the arachnoid granules. Meningiomas represent a special pathologic entity for neurosurgeons due to the fact that they can grow silently for a long time, and can affect important neural structures when they become symptomatic. The total resection of meningiomas is curative. For the meningiomas which are not surgically accessible and for reoccurrence. Gamma Knife radiosurgery (GKS) is a very efficient solution. Materials and methods. The study below presents the experience of the authors regarding the use of GKS for the treatment of meningiomas. The authors focus on a population of 550 patients diagnosed and treated for meningiomas over a period of 10 years at the „Bagdasar-Arseni“ University Hospital in Bucharest. This study compares the impact of GKS when performed alone or in association with open microneurosurgery. The authors assessed patients with tumors ranging between 1 and 42 cm3 in volume. GKS is used successfully to treat meningiomas, both independently and in association with open microsurgery. Results. The major complications of the treatment are represented by lack of response to treatment (7% of patients) and transient cerebral edema (22% of patients). A disturbing phenomenon happens in a few meningiomas of the convexity, with malignant edema (<1%). Conclusion. Given the multiple advantages it has, GKS is right now the tip of the spear regarding the therapeutical methods available for meningiomas. These tumors usually are benign in nature; however, a small percentage are malignant. Often, meningiomas cause no symptoms and require no immediate treatment. But the growth of benign meningiomas can cause serious problems. In some cases, such growth can be fatal. Typically, symptomatic meningiomas are treated with either radiosurgery or conventional surgery. When the tumors met in daily practice are larger than the therapeutical resources of the devices used for GKS, an open microsurgical approach may be attempted followed by stereotactic irradiation of the remnant tumor.

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Gamma Knife surgery of vestibular schwannomas: longitudinal changes in vestibular function and measurement of the Dizziness Handicap Inventory

Journal of Neurosurgery ◽

10.3171/jns/2008/109/12/s21 ◽

2008 ◽

Vol 109 (Supplement) ◽

pp. 137-143 ◽

Cited By ~ 18

Author(s):

P. Ashley Wackym ◽

Maureen T. Hannley ◽

Christina L. Runge-Samuelson ◽

Jamie Jensen ◽

Yong-Ran Zhu

Keyword(s):

Gamma Knife ◽

Vestibular Function ◽

Gamma Knife Surgery ◽

Vestibular Schwannomas ◽

Dizziness Handicap Inventory ◽

Longitudinal Changes ◽

Significant Difference ◽

The Impact ◽

Over Time

Object Gamma Knife surgery (GKS) is one of the methods available to treat vestibular schwannomas (VSs), in addition to microsurgical resection; however, clear information regarding balance function outcomes and the impact of treatment on patients' quality of life over time remains an important clinical need. The purpose of this study was to assess the longitudinal balance outcomes and Dizziness Handicap Inventory (DHI) following GKS for VSs. Methods This was a prospective clinical study of balance outcomes in all patients with VSs treated in the Acoustic Neuroma and Skull Base Surgery Program at a tertiary referral center by the senior author and the Gamma Knife team between June 2000 and May 2008. The main outcome measures included preoperative vestibular testing and postoperative caloric testing performed at 6-month intervals to determine vestibular function. The DHI questionnaires were administered retrospectively to assess the impact of GKS on self-perceived disability. Results Between June 2000 and May 2008, 55 sporadic VSs were treated. There was a ≥ 60-month follow-up available in 27 of these patients, ≥ 48 months in 32, ≥ 36 months in 38, ≥ 24 months in 43, ≥ 12 months in 51, and ≥ 6 months in 54 (1 patient was excluded from the analysis because the follow-up was < 6 months). Various patterns of changes in vestibular function were observed in either positive or negative directions. A significant difference in total DHI score was seen only in the elderly (> 65 years old) patients pre-GKS compared with post-GKS (t = 1.34, p = 0.05). Conclusions Longitudinal changes in vestibular function occur over time, with the largest changes seen in the first 6 months after treatment. Potential for clinical intervention, such as vestibular rehabilitation therapy, exists during this interval; however, larger cohorts must be studied to determine the timing and efficacy of this intervention. The statistically significant improvement in the DHI score in the patient cohort > 65 years old treated with GKS suggests that this group may benefit from this option when considering the symptom of dizziness.

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Biologically effective dose correlates with linear tumor volume changes after upfront single-fraction stereotactic radiosurgery for vestibular schwannomas

Neurosurgical Review ◽

10.1007/s10143-021-01538-w ◽

2021 ◽

Author(s):

Constantin Tuleasca ◽

Mohamed Faouzi ◽

Philippe Maeder ◽

Raphael Maire ◽

Jonathan Knisely ◽

...

Keyword(s):

Standard Deviation ◽

Effective Dose ◽

Stereotactic Radiosurgery ◽

Tumor Volume ◽

Vestibular Schwannomas ◽

Benign Tumors ◽

Biologically Effective Dose ◽

Volume Changes ◽

Single Fraction

AbstractVestibular schwannomas (VSs) are benign, slow-growing tumors. Management options include observation, surgery, and radiation. In this retrospective trial, we aimed at evaluating whether biologically effective dose (BED) plays a role in tumor volume changes after single-fraction first intention stereotactic radiosurgery (SRS) for VS. We compiled a single-institution experience (n = 159, Lausanne University Hospital, Switzerland). The indication for SRS was decided after multidisciplinary discussion. Only cases with minimum 3 years follow-up were included. The Koos grading, a reliable method for tumor classification was used. Radiosurgery was performed using Gamma Knife (GK) and a uniform marginal prescription dose of 12 Gy. Mean BED was 66.3 Gy (standard deviation 3.8, range 54.1–73.9). The mean follow-up period was 5.1 years (standard deviation 1.7, range 3–9.2). The primary outcome was changes in 3D volumes after SRS as function of BED and of integral dose received by the VS. Random-effect linear regression model showed that tumor volume significantly and linearly decreased over time with higher BED (p < 0.0001). Changes in tumor volume were also significantly associated with age, sex, number of isocenters, gradient index, and Koos grade. However, the effect of BED on tumor volume change was moderated by time after SRS and Koos grade. Lower integral doses received by the VSs were inversely correlated with BED in relationship with tumor volume changes (p < 0.0001). Six (3.4%) patients needed further intervention. For patients having uniformly received the same marginal dose prescription, higher BED linearly and significantly correlated with tumor volume changes after SRS for VSs. BED could represent a potential new treatment paradigm for patients with benign tumors, such as VSs, for attaining a desired radiobiological effect. This could further increase the efficacy and decrease the toxicity of SRS not only in benign tumors but also in other SRS indications.

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Letter to the Editor Regarding “Adjunctive Gamma Knife Surgery or Wait and Scan Policy After Optimal Resection of Large Vestibular Schwannomas: Clinical and Radiologic Outcomes”

World Neurosurgery ◽

10.1016/j.wneu.2018.10.038 ◽

2019 ◽

Vol 122 ◽

pp. 719-721 ◽

Cited By ~ 2

Author(s):

Constantin Tuleasca ◽

Roy Thomas Daniel ◽

Daniele Starnoni ◽

Mercy George ◽

Raphael Maire ◽

...

Keyword(s):

Gamma Knife ◽

Gamma Knife Surgery ◽

Vestibular Schwannomas ◽

Letter To The Editor

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Should Koos grade I vestibular schwannomas be treated early with gamma knife surgery? A subgroup analysis in a series of 190 consecutive patients

Neurochirurgie ◽

10.1016/j.neuchi.2014.10.028 ◽

2014 ◽

Vol 60 (6) ◽

pp. 331

Author(s):

M. Levivier ◽

C. Tuleasca ◽

G. Mercy ◽

L. Schiappacasse ◽

M. Zeverino ◽

...

Keyword(s):

Gamma Knife ◽

Subgroup Analysis ◽

Gamma Knife Surgery ◽

Vestibular Schwannomas

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Combined Approach for Large Vestibular Schwannomas: Planned Subtotal Resection Followed by Gamma Knife Surgery: An Update on a Series of 40 Consecutive Cases

10.1055/s-0037-1603844 ◽

2017 ◽

Author(s):

M. Levivier ◽

C. Tuleasca ◽

M. George ◽

L. Schiappacasse ◽

M. Marguet ◽

...

Keyword(s):

Gamma Knife ◽

Gamma Knife Surgery ◽

Vestibular Schwannomas ◽

Subtotal Resection ◽

Combined Approach

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Gamma Knife surgery of large meningiomas: early response to treatment

Acta Neurochirurgica ◽

10.1007/s00701-008-0166-4 ◽

2008 ◽

Vol 151 (1) ◽

pp. 1-8 ◽

Cited By ~ 28

Author(s):

J. C. Ganz ◽

W. A. Reda ◽

K. Abdelkarim

Keyword(s):

Gamma Knife ◽

Early Response ◽

Gamma Knife Surgery ◽

Response To Treatment

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Gamma knife surgery in the treatment of intracanalicular vestibular schwannomas

Acta Neurologica Scandinavica ◽

10.1111/ane.13220 ◽

2020 ◽

Vol 141 (5) ◽

pp. 415-422 ◽

Cited By ~ 2

Author(s):

Sebastian Dzierzęcki ◽

Grzegorz Turek ◽

Bartosz Czapski ◽

Katarzyna Dyttus‐Cebulok ◽

Ryszard Tomasiuk ◽

...

Keyword(s):

Gamma Knife ◽

Gamma Knife Surgery ◽

Vestibular Schwannomas

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Clinical, pathologic, and radiologic response in patients with neurofibromatosis type 2 (NF2) undergoing bevacizumab treatment.

Journal of Clinical Oncology ◽

10.1200/jco.2013.31.15_suppl.e13049 ◽

2013 ◽

Vol 31 (15_suppl) ◽

pp. e13049-e13049

Author(s):

Niamh Coleman ◽

Megan Greally ◽

Lynda O' Riordan ◽

Teresa Doyle ◽

Oscar S. Breathnach ◽

...

Keyword(s):

Hearing Loss ◽

Energy Levels ◽

Neurofibromatosis Type ◽

Vestibular Schwannomas ◽

Response To Treatment ◽

Benign Tumors ◽

Subjective Response ◽

Mri Imaging ◽

Profound Hearing Loss ◽

Bevacizumab Treatment

e13049 Background: NF2 is a rare inherited genetic condition characterized by multiple "benign" tumors in the peripheral and central nervous system. Profound hearing loss as a result of bilateral vestibular schwannomas is a major debilitating complication with a profound effect on quality of life. Vascular endothelial growth factor (VEGF) has been shown to be produced by vestibular schwannoma tumor cells. Bevacizumab, a humanized monoclonal antibody against VEGF, has been proposed as a treatment for patients with advanced NF2, who are poor candidates for surgery and radiation therapy. The aim of this study was to investigate and assess the benefit of treatment with bevacizumab in the treatment of patients with advanced NF2. Methods: Five patients with inoperable NF2 were assessed prospectively from 03/12-01/13. Pathological assessment of tissue for vascularity was performed in each of the patients’ tissue. Objective assessments, including audiogram and MRI brain, were performed pre- and during therapy. Qualitative assessments were undertaken to assess subjective response to treatment. Results: We identified 5 patients with advanced NF2 [n=5], 3 female 2 male with a median age 40 years [range 28 – 52] as outlined in the Table. Tumor-volume reduction of >20% was noted on MRI imaging in the vestibular schwannomas of 2 patients. 2 patients showed objective improvement on audiogram with subjective hearing improvement also noted. Other subjective responses noted include increased energy levels, less headaches, better concentration. Conclusions: Bevacizumab treatment in patients with advanced NF2 resulted in some symptomatic improvement, tumour shrinkage, improvement in disability. Patients with vestibular schwannomas appeared to receive the most benefit, and so in terms of palliation, the benefits may be most significant in patients with specific disabilities, such as hearing loss. [Table: see text]

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