Current Status of Radiosurgery for Arteriovenous Malformations

Object. The authors analyzed of the long-term complications that occur 2 or more years after gamma knife surgery (GKS) for intracranial arteriovenous malformations (AVMs). Methods. Patients with previously untreated intracranial AVMs that were managed by GKS and followed for at least 2 years after treatment were selected for analysis (237 cases). Complete AVM obliteration was attained in 130 cases (54.9%), and incomplete obliteration in 107 cases (45.1%). Long-term complications were observed in 22 patients (9.3%). These complications included hemorrhage (eight cases), delayed cyst formation (eight cases), increase of seizure frequency (four cases), and middle cerebral artery stenosis and increased white matter signal intensity on T2-weighted magnetic resonance imaging (one case of each). The long-term complications were associated with larger nidus volume (p < 0.001) and a lobar location of the AVM (p < 0.01). Delayed hemorrhage was associated only with incomplete obliteration of the nidus (p < 0.05). Partial obliteration conveyed no benefit. Delayed cyst formation was associated with a higher maximal GKS dose (p < 0.001), larger nidus volume (p < 0.001), complete nidus obliteration (p < 0.01), and a lobar location of the AVM (p < 0.05). Conclusions. Incomplete obliteration of the nidus is the most important factor associated with delayed hemorrhagic complications. Partial obliteration does not seem to reduce the risk of hemorrhage. Complete obliteration can be complicated by delayed cyst formation, especially if high maximal treatment doses have been administered.

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Photon Radiosurgery: A Clinical Review

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100042293 ◽

1992 ◽

Vol 19 (2) ◽

pp. 212-221 ◽

Cited By ~ 10

Author(s):

Michael R. McKenzie ◽

Luis Souhami ◽

Ervin B. Podgorsak ◽

André Olivier ◽

Jean-Louis Caron ◽

...

Keyword(s):

Linear Accelerator ◽

Arteriovenous Malformations ◽

Clinical Results ◽

Operating Costs ◽

Linear Accelerators ◽

Dose Distributions ◽

Acoustic Neurinomas ◽

Malignant Lesions ◽

High Doses ◽

Established Role

ABSTRACT:The term radiosurgery has been used to describe a variety of radiotherapy techniques which deliver high doses of radiation to small, stereotactically defined intracranial targets in such a way that the dose fall-off outside the targeted volume is very sharp. Proton, charged particle, gamma unit, and linear accelerator-based techniques appear to be equivalent from the standpoint of accuracy, dose distributions, and clinical results. However, capital and operating costs associated with the use of linear accelerators in general clinical use are much lower. Radiosurgery has an established role in the treatment of arteriovenous malformations and acoustic neurinomas. Interest in these techniques is increasing in neurosurgical and radiation oncological communities, as radiosurgery is rapidly assuming a place in the management of several other conditions, including craniopharyngiomas, meningiomas, and selected malignant lesions.

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Radiation Therapy for Arteriovenous Malformations: A Review

Neurosurgery ◽

10.1227/00006123-199005000-00001 ◽

1990 ◽

Vol 26 (5) ◽

pp. 725-735 ◽

Cited By ~ 91

Author(s):

Christopher S. Ogilvy

Keyword(s):

Proton Beam ◽

Gamma Knife ◽

Linear Accelerator ◽

Arteriovenous Malformations ◽

Proton Beam Therapy ◽

Recurrent Hemorrhage ◽

Brain Irradiation ◽

History Of ◽

Gamma Knife Therapy

Abstract There have been numerous case reports and series of patients treated with partial brain irradiation, linear accelerator-based radiosurgery, gamma knife radiosurgery, and Bragg peak therapy for inoperable arteriovenous malformations (AVMs). These cases are summarized and compared. There is convincing evidence that radiation therapy does have a role in obliterating carefully chosen inoperable lesions. The changes that occur in vessel walls after radiation are reviewed. Data about x-ray and gamma radiation are mostly historical and difficult to evaluate because of the techniques of partial brain irradiation. There is a lack of data about the volume of AVM treated and the minimum dose delivered to the AVM nidus. For gamma knife, heavy particle, and linear accelerator therapy, more complete data are available. The incidence of hemorrhage during the first 2 years after treatment, when radiation-induced vascular changes are proposed to occur, is approximately 2.6% per year for gamma knife therapy, 2% per year for proton beam therapy, 2.3% per year for helium beam therapy, and 2.3% per year for linear accelerator therapy. These rates are similar to the recurrence rate for hemorrhage of 2.2 to 3% per year expected based on the natural history of untreated AVMs. If AVM obliteration after therapy is not achieved, the incidence of recurrent hemorrhage remains between 2% per year after treatment with gamma knife therapy. The incidence of hemorrhage for all patients treated was reported as 0.15% per year in one study and 20% over 8 years in a follow-up study using proton beam therapy. Mortality from hemorrhage after treatment was 0.6% after gamma knife therapy, 2.3% after helium beam therapy, and 2 to 5% after proton beam therapy. These figures for mortality are all lower than the 11% observed for the natural history of untreated AVMs. Permanent neurological deficits experienced as a complication of radiation occurred in 2 to 3% of patients treated with gamma knife therapy, 4% of patients treated with helium beam therapy, 1.7% of patients treated with proton beam therapy, and 3% of patients treated with stereotactic linear accelerator therapy. Proton beam therapy has been used for both small and large lesions. The majority of lesions in patients treated with gamma knife, helium beam, and linear accelerator therapy have been small (usually less than 3.0 cm average diameter) lesions. In these patients with small inoperable lesions treated with accurately directed fields of isocentric radiation, the greatest incidence of AVM obliteration has been observed on follow-up angiograms. Larger lesions may undergo vascular wall thickening with subsequent protection from recurrent hemorrhage, but more data are needed to support this hypothesis.

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Outcome after hemorrhage following Gamma Knife surgery for cerebral arteriovenous malformations

Journal of Neurosurgery ◽

10.3171/2008.10.17675 ◽

2009 ◽

Vol 110 (5) ◽

pp. 1003-1009 ◽

Cited By ~ 10

Author(s):

Manish Kumar Kasliwal ◽

Shashank Sharad Kale ◽

Aditya Gupta ◽

Narayanam Anantha Sai Kiran ◽

Manish Singh Sharma ◽

...

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Venous Drainage ◽

Venous Hypertension ◽

Gamma Knife Surgery ◽

New Delhi ◽

Cerebral Arteriovenous Malformations ◽

Complete Obliteration ◽

Cerebral Avms ◽

Risk Of Hemorrhage

Object Although the effects of Gamma Knife surgery (GKS) on the risk of hemorrhage are poorly understood, a certain subset of patients does suffer bleeding after GKS. This study was undertaken to analyze the outcome of patients sustaining hemorrhage after GKS; it is the most feared complication of radiosurgical management of cerebral arteriovenous malformations (AVMs). Methods Between May 1997 and June 2006, 494 cerebral AVMs in 489 patients were treated using a Leksell Gamma Knife Model B, and follow-up evaluations were conducted until June 2007 at the All India Institute of Medical Sciences in New Delhi. Fourteen patients who sustained a hemorrhage after GKS formed the study group. In most of these patients conservative management was chosen. Results The mortality rate was 0% and there was a 7% risk of sustaining a severe deficit following rebleeding after GKS. None of the patients sustained rebleeding after complete obliteration. Patients with Spetzler-Martin Grade III or less had increased chances of hemorrhage after GKS (p < 0.002). The presence of deep venous drainage, aneurysm, venous hypertension, or periventricular location on angiography was common in patients with hemorrhage after GKS. Conclusions The risk of hemorrhage that remains following GKS for cerebral AVMs is highest in the 1st year after treatment. The present study showed a relatively good outcome even in cases with hemorrhage following GKS, with no deaths and minimal morbidity, further substantiating the safety and efficacy of the procedure.

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Treatment of arteriovenous malformations with linear accelerator–based radiosurgery compared with Gamma Knife surgery

Journal of Neurosurgery ◽

10.3171/sup.2006.105.7.58 ◽

2006 ◽

Vol 105 (Supplement) ◽

pp. 58-63 ◽

Cited By ~ 11

Author(s):

Peter Orio ◽

Keith J. Stelzer ◽

Robert Goodkin ◽

James G. Douglas

Keyword(s):

Ct Angiography ◽

Gamma Knife ◽

Linear Accelerator ◽

Arteriovenous Malformations ◽

Mr Angiography ◽

Gamma Knife Surgery ◽

Median Dose ◽

Obliteration Rate ◽

Linac Radiosurgery

ObjectThe authors sought to compare the outcomes of patients with arteriovenous malformations (AVMs) treated by Gamma Knife surgery (GKS) with those of patients treated by linear accelerator–based (LINAC) radiosurgery.MethodsOne hundred and eighty-seven patients with AVMs were treated at our institution between 1992 and 2003. Ninety-one patients were treated with GKS and 96 patients were treated with LINAC radiosurgery. Patient and treatment characteristics in the two groups included the following. In the LINAC group, the median age was 33 years (range 9–66 years); the median dose was 16 Gy (70% isodose line); the median treated AVM volume was 5.5 cm3; and 46% of patients in this group were treated after hemorrhage. In the GKS group, the median age was 38 years (range 6–63 years); the median dose was 20 Gy (50% isodose line); the median treated AVM volume was 4.3 cm3; and 44% of patients in this group were treated after hemorrhage. Obliteration of AVMs was determined by performing computed tomography (CT) angiography and/or magnetic resonance (MR) angiography and angiography. Patient follow-up evaluation included obtaining an MR angiogram/MR image or CT angiogram at 6 months, at 1 year, and then annually thereafter. Angiography was performed to confirm obliteration when MR angiography and/or CT angiography no longer revealed evidence of an AVM.The 5-year estimated AVM obliteration rate was 66% in the entire patient group; the LINAC group was 60%; the GKS group was 72%; this difference was not statistically significant (p = 0.97). Twelve patients who underwent treatment with LINAC radiosurgery underwent retreatment with GKS and one was retreated with LINAC radiosurgery. The obliteration rate was 82%. Six patients treated with GKS were retreated with GKS, but the follow-up time is of short duration. Chronic toxicity occurred in 8% of both the GKS and the LINAC groups (p = 0.61). Posttreatment hemorrhage during the time of risk before AVM obliteration was 13% in the GKS group and 6.2% in the LINAC group (p = 0.05).Conclusions Treatment of patients with AVMs by using LINAC radiosurgery and GKS treatment produces high obliteration rates with acceptable long-term radiation toxicity in the patients treated.

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Linear Accelerator Radiosurgery of Cerebral Arteriovenous Malformations: Current Status

Advances in Radiosurgery - Acta Neurochirurgica Supplementum ◽

10.1007/978-3-7091-9371-6_2 ◽

1994 ◽

pp. 5-9 ◽

Cited By ~ 17

Author(s):

Federico Colombo ◽

F. Pozza ◽

G. Chierego ◽

P. Francescon ◽

L. Casentini ◽

...

Keyword(s):

Linear Accelerator ◽

Arteriovenous Malformations ◽

Current Status ◽

Cerebral Arteriovenous Malformations

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Factors Determining the Clinical Complications of Radiosurgery for AVM

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100015936 ◽

2013 ◽

Vol 40 (6) ◽

pp. 807-813 ◽

Cited By ~ 3

Author(s):

Matylda Machnowska ◽

Patamintita Taeshineetanakul ◽

Sasikhan Geibprasert ◽

Ravi Menezes ◽

Ronit Agid ◽

...

Keyword(s):

Gamma Knife ◽

Linear Accelerator ◽

Arteriovenous Malformations ◽

Radiation Effects ◽

Gamma Knife Radiosurgery ◽

Neurological Deficits ◽

Clinical Complications ◽

Signal Change ◽

Data Pretreatment ◽

Post Radiation

Purpose:To identify the predictors of symptomatic post-radiation T2 signal change in patients with arteriovenous malformations (AVM) treated with radiosurgery.Materials and Methods:The charts of 211 consecutive patients with arteriovenous malformations treated with either gamma knife radisurgery or linear accelerator radiosurgery between 2000-2009 were retrospectively reviewed. 168 patients had a minimum of 12 months of clinical and radiologic follow-up following the procedure and complete dosage data. Pretreatment characteristics and dosimetric variables were analyzed to identify predictors of adverse radiation effects.Results:141 patients had no clinical symptomatic complications. 21 patients had global or focal neurological deficits attributed to symptomatic edema. Variables associated with development of symptomatic edema included a non-hemorrhagic symptomatic presentation compared to presentation with hemorrhage, p=0.001; OR (95%CI) = 6.26 (1.99, 19.69); the presence of venous rerouting compared to the lack of venous rerouting, p=0.031; OR (95% CI) = 3.25 (1.20, 8.80); radiosurgery with GKS compared to linear accelerator radiosurgery p = 0.012; OR (95% CI) = 4.58 (1.28, 16.32); and the presence of more than one draining vein compared to a single draining vein p = 0.032; OR (95% CI) = 2.82 (1.06, 7.50).Conclusions:We postulated that the higher maximal doses used with gamma knife radiosurgery may be responsible for the greater number of adverse radiation effects with this modality compared to linear accelerator radiosurgery. We found that AVMs with greater venous complexity and therefore instability resulted in more adverse treatment outcomes, suggesting that AVM angioarchitecture should be considered when making treatment decisions.

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Gamma Knife Radiosurgery for Incidental, Symptomatic Unruptured, and Ruptured Brain Arteriovenous Malformations

Cerebrovascular Diseases ◽

10.1159/000513280 ◽

2021 ◽

Vol 50 (2) ◽

pp. 222-230

Author(s):

Byung Sup Kim ◽

Je Young Yeon ◽

Hyung Shik Shin ◽

Jong-Soo Kim ◽

Seung-Chyul Hong ◽

...

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Gamma Knife Radiosurgery ◽

Venous Drainage ◽

Age At Diagnosis ◽

Significant Difference ◽

Ruptured Avm ◽

The Mean ◽

Risk Of Hemorrhage ◽

Brain Avms

Background: This study was performed to investigate clinical characteristics and outcome after gamma knife radiosurgery (GKS) in patients with incidental, symptomatic unruptured, or ruptured arteriovenous malformations (AVMs). Methods: A total of 491 patients with brain AVMs treated with GKS from June 2002 to September 2017 were retrospectively reviewed. All patients were classified into the incidental (n = 105), symptomatic unruptured (n = 216), or ruptured AVM (n = 170) groups. Results: The mean age at diagnosis of incidental, symptomatic unruptured, and ruptured AVMs was 40.3, 36.7, and 27.6 years, respectively. The mean nidus volume was 3.9, 5.7, and 2.4 cm3, respectively. Deep venous drainage was identified in 34, 54, and 76% patients, respectively. There were no significant differences in obliteration rates after GKS between the 3 groups (64.8, 61.1, and 65.9%, respectively) after a mean follow-up period of 60.5 months; however, patients with incidental AVM had a significantly lower post-GKS hemorrhage rate than patients with symptomatic unruptured or ruptured AVMs (annual hemorrhage rate of 1.07, 2.87, and 2.69%; p = 0.028 and p = 0.049, respectively). Conclusions: There is a significant difference in clinical and anatomical characteristics between incidental, symptomatic unruptured, and ruptured AVMs. The obliteration rate after GKS is not significantly different between the 3 groups. Meanwhile, an older age at diagnosis and lower hemorrhage rate after GKS in incidental AVMs suggest that they have a more indolent natural course with a lower life-long risk of hemorrhage.

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Long-term complications after gamma knife surgery for arteriovenous malformations

Journal of Neurosurgery ◽

10.3171/jns.2005.102.s_supplement.0034 ◽

2005 ◽

Vol 102 ◽

pp. 34-37 ◽

Cited By ~ 69

Author(s):

Masahiro Izawa ◽

Motohiro Hayashi ◽

Mikhail Chernov ◽

Koutarou Nakaya ◽

Taku Ochiai ◽

...

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Cyst Formation ◽

Gamma Knife Surgery ◽

Content Type ◽

Delayed Hemorrhage ◽

Complete Obliteration ◽

Risk Of Hemorrhage ◽

Fine Print

Object. The authors analyzed of the long-term complications that occur 2 or more years after gamma knife surgery (GKS) for intracranial arteriovenous malformations (AVMs). Methods. Patients with previously untreated intracranial AVMs that were managed by GKS and followed for at least 2 years after treatment were selected for analysis (237 cases). Complete AVM obliteration was attained in 130 cases (54.9%), and incomplete obliteration in 107 cases (45.1%). Long-term complications were observed in 22 patients (9.3%). These complications included hemorrhage (eight cases), delayed cyst formation (eight cases), increase of seizure frequency (four cases), and middle cerebral artery stenosis and increased white matter signal intensity on T2-weighted magnetic resonance imaging (one case of each). The long-term complications were associated with larger nidus volume (p < 0.001) and a lobar location of the AVM (p < 0.01). Delayed hemorrhage was associated only with incomplete obliteration of the nidus (p < 0.05). Partial obliteration conveyed no benefit. Delayed cyst formation was associated with a higher maximal GKS dose (p < 0.001), larger nidus volume (p < 0.001), complete nidus obliteration (p < 0.01), and a lobar location of the AVM (p < 0.05). Conclusions. Incomplete obliteration of the nidus is the most important factor associated with delayed hemorrhagic complications. Partial obliteration does not seem to reduce the risk of hemorrhage. Complete obliteration can be complicated by delayed cyst formation, especially if high maximal treatment doses have been administered.

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