scholarly journals Volume-staged versus dose-staged radiosurgery outcomes for large intracranial arteriovenous malformations

2014 ◽  
Vol 37 (3) ◽  
pp. E18 ◽  
Author(s):  
Shayan Moosa ◽  
Ching-Jen Chen ◽  
Dale Ding ◽  
Cheng-Chia Lee ◽  
Srinivas Chivukula ◽  
...  
Keyword(s):  
Arteriovenous Malformations ◽  
English Language ◽  
Latency Period ◽  
Complication Rates ◽  
Single Session ◽  
Complete Obliteration ◽  
Radiation Induced ◽  
The Mean ◽  
Superior Approach ◽  
Induced Changes

Object The aim in this paper was to compare the outcomes of dose-staged and volume-staged stereotactic radio-surgery (SRS) in the treatment of large (> 10 cm3) arteriovenous malformations (AVMs). Methods A systematic literature review was performed using PubMed. Studies written in the English language with at least 5 patients harboring large (> 10 cm3) AVMs treated with dose- or volume-staged SRS that reported post-treatment outcomes data were selected for review. Demographic information, radiosurgical treatment parameters, and post-SRS outcomes and complications were analyzed for each of these studies. Results The mean complete obliteration rates for the dose- and volume-staged groups were 22.8% and 47.5%, respectively. Complete obliteration was demonstrated in 30 of 161 (18.6%) and 59 of 120 (49.2%) patients in the dose- and volume-staged groups, respectively. The mean rates of symptomatic radiation-induced changes were 13.5% and 13.6% in dose- and volume-staged groups, respectively. The mean rates of cumulative post-SRS latency period hemorrhage were 12.3% and 17.8% in the dose- and volume-staged groups, respectively. The mean rates of post-SRS mortality were 3.2% and 4.6% in dose- and volume-staged groups, respectively. Conclusions Volume-staged SRS affords higher obliteration rates and similar complication rates compared with dose-staged SRS. Thus, volume-staged SRS may be a superior approach for large AVMs that are not amenable to single-session SRS. Staged radiosurgery should be considered as an efficacious component of multimodality AVM management.

Effect of Prior Hemorrhage on Intracranial Arteriovenous Malformation Radiosurgery Outcomes

2014 ◽  
Vol 39 (1) ◽  
pp. 53-62 ◽  
Author(s):  
Dale Ding ◽  
Chun-Po Yen ◽  
Robert M. Starke ◽  
Zhiyuan Xu ◽  
Jason P. Sheehan
Keyword(s):  
Gamma Knife Radiosurgery ◽  
Latency Period ◽  
Time Interval ◽  
Intracranial Arteriovenous Malformation ◽  
Complete Obliteration ◽  
History Of ◽  
Radiation Induced ◽  
Prescription Dose ◽  
The Mean ◽  
Induced Changes

Background: Intracerebral hemorrhage is simultaneously the most frequent and most debilitating manifestation of intracranial arteriovenous malformations (AVM), but its impact on success and complications of radiosurgery has not been rigorously assessed. In this case-control study, we define the effect of prior hemorrhage on AVM radiosurgery outcomes. Methods: From a prospective, institutional database of 1,400 AVM patients treated with Gamma Knife radiosurgery, unruptured and ruptured AVMs were matched in a 1:1 fashion, blinded to outcome, based on patient demographics, prior embolization (26.6% of each cohort), AVM size (mean volume of unruptured AVMs 3.7 cm3 versus ruptured AVMs 3.5 cm3, p = 0.195), Spetzler-Martin grade (Grade I 17.0%, Grade II 37.8%, Grade III 34.8%, Grade IV 10.4% for each cohort), and radiosurgical treatment parameters (mean prescription dose for unruptured AVMs 20.9 Gy versus ruptured AVMs 21.0 Gy, p = 0.837). There were 270 patients in each cohort. Matched statistical analyses were used to compare the baseline characteristics, obliteration rates, post-radiosurgery latency period hemorrhage risks, and incidences of radiation-induced changes (RIC) between the two cohorts. Results: The actuarial obliteration rates of the two cohorts were similar (unruptured AVMs: 38, 58, and 76% at 3, 5, 10 years, respectively; ruptured AVMs: 40, 60, and 73% at 3, 5, 10 years, respectively; p = 0.592). However, for embolized AVMs, complete obliteration was more likely to be achieved in unruptured lesions (unruptured AVMs: 25, 32, and 54% at 3, 5, 10 years, respectively; ruptured AVMs: 18, 27, and 42% at 3, 5, 10 years, respectively; p = 0.038). Prior AVM rupture resulted in a higher annual risk of post-radiosurgery latency period hemorrhage (ruptured AVMs 2.3% versus unruptured AVMs 1.1%, p = 0.025) but a lower rate of cumulative and symptomatic RIC (cumulative RIC: ruptured AVMs 30.4% versus unruptured AVMs 48.9%, p < 0.0001; symptomatic RIC: ruptured AVMs 7.0% versus unruptured AVMs 12.2%, p = 0.041, respectively). The rates of permanent RIC were similar between the unruptured (2.2%) and ruptured (1.9%) AVM cohorts (p = 0.761). The mean time interval to onset of RIC (unruptured AVMs 13.3 months versus ruptured AVMs 12.1 months, p = 0.783), and the mean duration of RIC (unruptured AVMs 22.0 months versus ruptured AVMs 21.7 months, p = 0.599) were not significantly different between the two cohorts. Conclusions: Prior AVM rupture significantly alters the risk of latency period hemorrhage and RIC following radiosurgery. These effects should be taken into consideration with the multidisciplinary management of AVM patients. Radiosurgery does not significantly alter the natural history of the hemorrhage risks of unruptured and ruptured AVMs unless obliteration is achieved.

scholarly journals International multicenter cohort study of pediatric brain arteriovenous malformations. Part 2: Outcomes after stereotactic radiosurgery

2017 ◽  
Vol 19 (2) ◽  
pp. 136-148 ◽  
Author(s):  
Robert M. Starke ◽  
Dale Ding ◽  
Hideyuki Kano ◽  
David Mathieu ◽  
Paul P. Huang ◽  
...  
Keyword(s):  
Cohort Study ◽  
Stereotactic Radiosurgery ◽  
Arteriovenous Malformations ◽  
Latency Period ◽  
Favorable Outcome ◽  
Brain Arteriovenous Malformations ◽  
Radiation Induced ◽  
The Mean ◽  
Induced Changes

OBJECTIVE Pediatric patients (age < 18 years) harboring brain arteriovenous malformations (AVMs) are burdened with a considerably higher cumulative lifetime risk of hemorrhage than adults. Additionally, the pediatric population was excluded from recent prospective comparisons of intervention versus conservative management for unruptured AVMs. The aims of this multicenter, retrospective cohort study are to analyze the outcomes after stereotactic radiosurgery for unruptured and ruptured pediatric AVMs. METHODS We analyzed and pooled AVM radiosurgery data from 7 participating in the International Gamma Knife Research Foundation. Patients younger than 18 years of age who had at least 12 months of follow-up were included in the study cohort. Favorable outcome was defined as AVM obliteration, no post-radiosurgical hemorrhage, and no permanently symptomatic radiation-induced changes (RIC). The post-radiosurgery outcomes of unruptured versus ruptured pediatric AVMs were compared, and statistical analyses were performed to identify predictive factors. RESULTS The overall pediatric AVM cohort comprised 357 patients with a mean age of 12.6 years (range 2.8–17.9 years). AVMs were previously treated with embolization, resection, and fractionated external beam radiation therapy in 22%, 6%, and 13% of patients, respectively. The mean nidus volume was 3.5 cm3, 77% of AVMs were located in eloquent brain areas, and the Spetzler-Martin grade was III or higher in 59%. The mean radiosurgical margin dose was 21 Gy (range 5–35 Gy), and the mean follow-up was 92 months (range 12–266 months). AVM obliteration was achieved in 63%. During a cumulative latency period of 2748 years, the annual post-radiosurgery hemorrhage rate was 1.4%. Symptomatic and permanent radiation-induced changes occurred in 8% and 3%, respectively. Favorable outcome was achieved in 59%. In the multivariate logistic regression analysis, the absence of prior AVM embolization (p = 0.001) and higher margin dose (p < 0.001) were found to be independent predictors of a favorable outcome. The rates of favorable outcome for patients treated with a margin dose ≥ 22 Gy vs < 22 Gy were 78% (110/141 patients) and 47% (101/216 patients), respectively. A margin dose ≥ 22 Gy yielded a significantly higher probability of a favorable outcome (p < 0.001). The unruptured and ruptured pediatric AVM cohorts included 112 and 245 patients, respectively. Ruptured AVMs had significantly higher rates of obliteration (68% vs 53%, p = 0.005) and favorable outcome (63% vs 51%, p = 0.033), with a trend toward a higher incidence of post-radiosurgery hemorrhage (10% vs 4%, p = 0.07). The annual post-radiosurgery hemorrhage rates were 0.8% for unruptured and 1.6% for ruptured AVMs. CONCLUSIONS Radiosurgery is a reasonable treatment option for pediatric AVMs. Obliteration and favorable outcomes are achieved in the majority of patients. The annual rate of latency period hemorrhage after radiosurgery for both ruptured and unruptured pediatric AVM patients conveys a significant risk until the nidus is obliterated.

Abstract 190: Hemorrhage of Cerebral Arteriovenous Malformations Significantly Alters Stereotactic Radiosurgery Outcomes

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Dale Ding ◽  
Chun-Po Yen ◽  
Robert M Starke ◽  
Zhiyuan Xu ◽  
Jason P Sheehan
Keyword(s):  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Latency Period ◽  
Cerebral Arteriovenous Malformations ◽  
Patient Demographics ◽  
Complete Obliteration ◽  
Radiation Induced ◽  
Prescription Dose ◽  
Martin Grade ◽  
Induced Changes

Introduction: Intracranial hemorrhage is simultaneously the most frequent and most debilitating manifestation of cerebral arteriovenous malformations (AVM), but its impact on success and complications of radiosurgery has not been rigorously assessed. In this case-control study, we define the effect of prior hemorrhage on AVM radiosurgery outcomes. Methods: From a prospective, institutional database of 1400 AVM patients treated with Gamma Knife radiosurgery, unruptured and ruptured AVMs were matched in a 1:1 fashion, blinded to outcome, based on patient demographics, prior embolization, AVM size (mean volume of unruptured AVMs 3.7 cm3 versus ruptured AVMs 3.5 cm3, P=0.195), Spetzler-Martin grade and radiosurgical treatment parameters (mean prescription dose for unruptured AVMs 20.9 Gy versus ruptured AVMs 21.0 Gy, P=0.837). There were 270 patients in each cohort. Matched statistical analyses were used to compare the baseline characteristics, obliteration rates, post-radiosurgery latency period hemorrhage risks, and incidences of radiation-induced changes (RIC) between the two cohorts. Results: The actuarial obliteration rates of the two cohorts were similar (unruptured AVMs: 38%, 58%, 76% at 3, 5, 10 years, respectively; ruptured AVMs: 40%, 60%, 73% at 3, 5, 10 years, respectively; P=0.592). However, for embolized AVMs, complete obliteration was more likely to be achieved in unruptured lesions (unruptured AVMs: 25%, 32%, 54% at 3, 5, 10 years, respectively; ruptured AVMs: 18%, 27%, 42% at 3, 5, 10 years, respectively; P=0.038). Prior AVM rupture resulted in a higher annual risk of post-radiosurgery latency period hemorrhage (ruptured AVMs 2.3% versus unruptured AVMs 1.1%, P=0.025) but a lower rate of cumulative and symptomatic RIC (cumulative RIC: ruptured AVMs 30.4% versus unruptured AVMs 48.9%, P<0.0001; symptomatic RIC: ruptured AVMs 7.0% versus unruptured AVMs 12.2%, P=0.041, respectively). The rates of permanent RIC were similar between the unruptured (2.2%) and ruptured (1.9%) AVM cohorts (P=0.761). Conclusion: Prior AVM rupture significantly alters the risk of latency period hemorrhage and RIC following radiosurgery. These effects should be taken into consideration with the multidisciplinary management of AVM patients.

Volume-staged versus dose-staged stereotactic radiosurgery outcomes for large brain arteriovenous malformations: a systematic review

2018 ◽  
Vol 128 (1) ◽  
pp. 154-164 ◽  
Author(s):  
Adeel Ilyas ◽  
Ching-Jen Chen ◽  
Dale Ding ◽  
Davis G. Taylor ◽  
Shayan Moosa ◽  
...  
Keyword(s):  
Systematic Review ◽  
Stereotactic Radiosurgery ◽  
Arteriovenous Malformations ◽  
Management Strategy ◽  
Individual Patient Data ◽  
Brain Arteriovenous Malformations ◽  
Large Brain ◽  
Radiation Induced ◽  
The Mean ◽  
Induced Changes

OBJECTIVESeveral recent studies have improved our understanding of the outcomes of volume-staged (VS) and dose-staged (DS) stereotactic radiosurgery (SRS) for the treatment of large (volume > 10 cm3) brain arteriovenous malformations (AVMs). In light of these recent additions to the literature, the aim of this systematic review is to provide an updated comparison of VS-SRS and DS-SRS for large AVMs.METHODSA systematic review of the literature was performed using PubMed to identify cohorts of 5 or more patients with large AVMs who had been treated with VS-SRS or DS-SRS. Baseline data and post-SRS outcomes were extracted for analysis.RESULTSA total of 11 VS-SRS and 10 DS-SRS studies comprising 299 and 219 eligible patients, respectively, were included for analysis. The mean obliteration rates for VS-SRS and DS-SRS were 41.2% (95% CI 31.4%–50.9%) and 32.3% (95% CI 15.9%–48.8%), respectively. Based on pooled individual patient data, the outcomes for patients treated with VS-SRS were obliteration in 40.3% (110/273), symptomatic radiation-induced changes (RICs) in 13.7% (44/322), post-SRS hemorrhage in 19.5% (50/256), and death in 7.4% (24/323); whereas the outcomes for patients treated with DS-SRS were obliteration in 32.7% (72/220), symptomatic RICs in 12.2% (31/254), post-SRS hemorrhage in 10.6% (30/282), and death in 4.6% (13/281).CONCLUSIONSVolume-staged SRS appears to afford higher obliteration rates than those achieved with DS-SRS, although with a less favorable complication profile. Therefore, VS-SRS or DS-SRS may be a reasonable treatment approach for large AVMs, either as stand-alone therapy or as a component of a multimodality management strategy.

104 Stereotactic Radiosurgery for Spetzler-Martin Grade IV and V Arteriovenous Malformations: An International Multicenter Study

Neurosurgery ◽  
2017 ◽  
Vol 64 (CN_suppl_1) ◽  
pp. 220-221
Author(s):  
Jason P Sheehan ◽  
Mohana Rao Patibandla ◽  
Dale Ding ◽  
Hideyuki Kano ◽  
Zhiyuan Xu ◽  
...  
Keyword(s):  
Stereotactic Radiosurgery ◽  
Arteriovenous Malformations ◽  
Independent Predictor ◽  
Multivariate Logistic Regression Analysis ◽  
Favorable Outcome ◽  
Single Session ◽  
Radiation Induced ◽  
International Multicenter Study ◽  
Induced Changes

Abstract INTRODUCTION Due to the complexity of Spetzler-Martin (SM) grade IV-V arteriovenous malformations (AVM), the management of these lesions remains controversial. The aims of this multicenter, retrospective study are to evaluate outcomes after single-session stereotactic radiosurgery (SRS) for SM grade IV-V AVMs and determine predictive factors. METHODS We pooled data from 233 patients (mean age 33 years) with SM grade IV (94.4%) or V AVMs (5.6%) treated with single-session SRS at eight participating centers in the International Gamma Knife Research Foundation. Pre-SRS embolization was performed in 71 AVMs (30.5%). The mean nidus volume, SRS margin dose, and follow-up duration were 9.7 cc, 17.3 Gy, and 84.5 months, respectively. RESULTS >At a mean follow-up interval of 84.5 months, favorable outcome was defined as AVM obliteration, no post-SRS hemorrhage, and no permanently symptomatic radiation-induced changes (RIC) and was achieved in 26.2% of patients. The actuarial obliteration rates at 3, 7, 10, and 12 years were 15%, 34%, 37% and 42%, respectively. The annual post-SRS hemorrhage rate was 3.0%. Symptomatic and permanent RIC occurred in 10.7% and 4% of the patients, respectively. Only larger AVM diameter (P = 0.04) found to be an independent predictor of unfavorable outcome in the multivariate logistic regression analysis. The rate of favorable outcome was significantly lower for unruptured SM grade IV-V AVMs compared to ruptured ones (P = 0.042). Prior embolization was a negative independent predictor of AVM obliteration (P = 0.024) and radiologically evident RIC (P = 0.05) in multivariate analyses. CONCLUSION In this multi-institutional study, single session SRS had limited efficacy in the management of SM grade IV-V AVMs Favorable outcome was only achieved in a minority of unruptured SM grade IV-V AVMs, which supports less frequent utilization of SRS for the management of these lesions. A volume staged SRS approach for large AVMs represents an alternative approach for high grade AVM’s, but it requires further investigation.

Radiosurgery for patients with unruptured intracranial arteriovenous malformations

2013 ◽  
Vol 118 (5) ◽  
pp. 958-966 ◽  
Author(s):  
Dale Ding ◽  
Chun-Po Yen ◽  
Zhiyuan Xu ◽  
Robert M. Starke ◽  
Jason P. Sheehan
Keyword(s):  
Arteriovenous Malformations ◽  
Cox Regression ◽  
Univariate Analysis ◽  
Cyst Formation ◽  
Intracranial Arteriovenous Malformations ◽  
Radiation Induced ◽  
Prescription Dose ◽  
Martin Grade ◽  
The Mean ◽  
Induced Changes

Object The appropriate management of unruptured intracranial arteriovenous malformations (AVMs) remains controversial. In the present study, the authors evaluate the radiographic and clinical outcomes of radiosurgery for a large cohort of patients with unruptured AVMs. Methods From a prospective database of 1204 cases of AVMs involving patients treated with radiosurgery at their institution, the authors identified 444 patients without evidence of rupture prior to radiosurgery. The patients' mean age was 36.9 years, and 50% were male. The mean AVM nidus volume was 4.2 cm3, 13.5% of the AVMs were in a deep location, and 44.4% were at least Spetzler-Martin Grade III. The median radiosurgical prescription dose was 20 Gy. Univariate and multivariate Cox regression analyses were used to determine risk factors associated with obliteration, postradiosurgery hemorrhage, radiation-induced changes, and postradiosurgery cyst formation. The mean duration of radiological and clinical follow-up was 76 months and 86 months, respectively. Results The cumulative AVM obliteration rate was 62%, and the postradiosurgery annual hemorrhage rate was 1.6%. Radiation-induced changes were symptomatic in 13.7% and permanent in 2.0% of patients. The statistically significant independent positive predictors of obliteration were no preradiosurgery embolization (p < 0.001), increased prescription dose (p < 0.001), single draining vein (p < 0.001), radiological presence of radiation-induced changes (p = 0.004), and lower Spetzler-Martin grade (p = 0.016). Increased volume and higher Pittsburgh radiosurgery-based AVM score were predictors of postradiosurgery hemorrhage in the univariate analysis only. Clinical deterioration occurred in 30 patients (6.8%), more commonly in patients with postradiosurgery hemorrhage (p = 0.018). Conclusions Radiosurgery afforded a reasonable chance of obliteration of unruptured AVMs with relatively low rates of clinical and radiological complications.

scholarly journals Late complications of radiosurgery for cerebral arteriovenous malformations: report of 5 cases of chronic encapsulated intracerebral hematomas and review of the literature

2020 ◽  
Author(s):  
Stephanos Finitsis ◽  
René Anxionnat ◽  
Valerie Bernier ◽  
Isabelle Buccheit ◽  
Olivier Klein ◽  
...  
Keyword(s):  
Late Complication ◽  
Latency Period ◽  
Surgical Excision ◽  
Complete Removal ◽  
Late Complications ◽  
Cystic Component ◽  
Complete Obliteration ◽  
Radiation Induced ◽  
Early Radiation ◽  
Induced Changes

Abstract Background: Chronic encapsulated intracerebral hematomas (CEIHs) are a rare, late complication of radiosurgery for intracranial AVM. We present 5 cases treated mostly by surgical excision and review the literature. Methods: Patients (age 39, 42, 36, 31, 62) presented with headache, paresthesia, hemiparesis or were asymptomatic. CEIHs presented 10 to 13 years (median 12 years) post radiosurgery. Three patients had demonstrated early radiation induced changes post radiosurgery. Angiographic cure, assessed with DSA, was present in all cases except 1 case with a small nidus remnant. MRI demonstrated mixed lesions with a solid enhancing part, organized hematoma and extensive surrounding edema while three cases had also a cystic component. Results: Excision of the CEIHs with complete or partial removal of the capsule was perfomed in 4 patients and resulted in marked clinical improvement. On patient was managed conservatively with administration of steroids as surgery was judged excessively hazardous with eventual stabilization of his symptoms. Conclusions: CEIHs are rare, late complications of radiosurgery for cranial AVM. They may be asymptomatic or provoke symptoms and may be preceded by early radiation induced changes. Complete removal of CEIHS is an effective treatment. Because of the long latency period of CEIHs, patients who had radiosurgery for brain AVMs should be followed by MRI at least 10 years even after complete obliteration.

scholarly journals Late complications of radiosurgery for cerebral arteriovenous malformations: report of 5 cases of chronic encapsulated intracerebral hematomas and review of the literature.

2020 ◽  
Author(s):  
Stephanos Finitsis ◽  
Valerie Bernier ◽  
Isabelle Buccheit ◽  
Olivier Klein ◽  
Serge Bracard ◽  
...  
Keyword(s):  
Late Complication ◽  
Latency Period ◽  
Surgical Excision ◽  
Complete Removal ◽  
Late Complications ◽  
Complete Obliteration ◽  
Radiation Induced ◽  
Early Radiation ◽  
Brain Avms ◽  
Induced Changes

Abstract Background: Chronic encapsulated intracerebral hematomas (CEIHs) are a rare, late complication of radiosurgery for intracranial AVM. We present 5 cases treated mostly by surgical excision and review the literature.Methods: Patients (age 39, 42, 36, 31, 62) presented with headache, paresthesia, hemiparesis or were asymptomatic. CEIHs presented 10 to 13 years (median 12 years) post radiosurgery. Three patients had demonstrated early radiation induced changes post radiosurgery. Angiographic cure, assessed with DSA, was present in all cases except 1 case with a small nidus remnant. MRI demonstrated mixed lesions with a solid enhancing part, organized hematoma and extensive surrounding edema while three cases had also a cystic component.Results: Excision of the CEIHs with complete or partial removal of the capsule was performed in 4 patients and resulted in marked clinical improvement. One patient was managed conservatively with administration of steroids as surgery was judged excessively hazardous with eventual stabilization of his symptoms.Conclusions: CEIHs are rare, late complications of radiosurgery for cranial AVM. They may be asymptomatic or provoke symptoms and may be preceded by early radiation induced changes. Complete removal of CEIHS is an effective treatment. Because of the long latency period of CEIHs, patients who had radiosurgery for brain AVMs should be followed by MRI at least 10 years even after complete obliteration.

scholarly journals Predictive Factors of Radiation-Induced Changes Following Single-Session Gamma Knife Radiosurgery for Arteriovenous Malformations

2021 ◽  
Vol 10 (10) ◽  
pp. 2186
Author(s):  
Myung Ji Kim ◽  
Kyung Won Chang ◽  
So Hee Park ◽  
Won Seok Chang ◽  
Jong Hee Chang ◽  
...  
Keyword(s):  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Gamma Knife Radiosurgery ◽  
Inverse Correlation ◽  
Brain Parenchyma ◽  
Magnetic Resonance Images ◽  
Single Session ◽  
Radiation Induced ◽  
Induced Changes

We evaluated for possible predictors of radiation-induced changes (RICs) after gamma knife radiosurgery (GKRS) for arteriovenous malformations (AVMs). We identified the nidal component within AVMs to analyze the correlation between the volume of brain parenchyma within the 50% isodose line (IDL) and RICs. We retrospectively reviewed patients with AVMs who underwent a single-session of GKRS at our institution between 2007 and 2017 with at least a 2-year minimum follow-up. Follow-up magnetic resonance images were evaluated for newly developed T2 signal changes and the proportions of nidus and intervening parenchyma were quantified. A total of 180 AVM patients (98 males and 82 females) with a median age of 34 years were included in the present study. The overall obliteration rate was 67.8%. The median target volume was 3.65 cc. The median nidus and parenchyma volumes within the 50% IDL were 1.54 cc and 2.41 cc, respectively. RICs were identified in 79 of the 180 patients (43.9%). AVMs associated with previous hemorrhages showed a significant inverse correlation with RICs. In a multivariate analysis, RICs were associated with a higher proportion of brain parenchyma within the 50% IDL (hazard ratio (HR) 169.033; p < 0.001) and inversely correlated with the proportion of nidus volume within the 50% IDL (HR 0.006; p < 0.001). Our study identified that a greater proportion of brain tissue between the nidus within the 50% IDL was significantly correlated with RICs. Nidus angioarchitectural complexity and the absence of a prior hemorrhage were also associated with RICs. The identification of possible predictors of RICs could facilitate radiosurgical planning and treatment decisions as well as the planning of appropriate follow-up after GKRS; this could minimize the risk of RICs, which would be particularly beneficial for the treatment of incidentally found asymptomatic AVMs.

Long-term Results of Gamma Knife Surgery for Partially Embolized Arteriovenous Malformations

Neurosurgery ◽  
2012 ◽  
Vol 71 (6) ◽  
pp. 1139-1148 ◽  
Author(s):  
Lucia Schwyzer ◽  
Chun-Po Yen ◽  
Avery Evans ◽  
Sebastian Zavoian ◽  
Ladislau Steiner
Keyword(s):  
Gamma Knife ◽  
Arteriovenous Malformations ◽  
Combined Treatment ◽  
Gamma Knife Surgery ◽  
Long Term Results ◽  
Historical Series ◽  
Radiation Induced ◽  
The Mean ◽  
Induced Changes

ABSTRACT BACKGROUND: The effectiveness and risk of Gamma Knife surgery (GKS) in the management of partially embolized cerebral arteriovenous malformations (AVMs) remain to be elucidated. OBJECTIVE: To evaluate the long-term imaging and clinical outcomes of GKS in AVM patients who had undergone previous partial embolization and compare the results with patients treated with GKS alone. METHODS: A total of 215 embolized AVMs were analyzed. The mean patient age was 32.9 years. The mean volume of the nidus was 4.6 mL (range, 0.1-29.4 mL), and the mean prescription dose was 19.6 Gy (range, 4-28 Gy). This group was compared with 729 nonembolized AVMs. RESULTS: After embolization and GKS, angiographically confirmed total obliteration of the AVMs was significantly lower (33%) compared with patients in whom GKS was used alone (60.9%; P &lt; .001). However, the mean nidus size was larger and the Spetzler-Martin grade was higher for the embolized AVMs compared with the nonembolized AVMs. Radiation-induced changes occurred more often in the embolized (43.4%) than the nonembolized (33.4%) AVMs (P = .028). Permanent neurological deficits associated with radiation-induced changes occurred in 2.7% of the embolized compared with 1.3% of the nonembolized patients (P = .14). CONCLUSION: In our retrospective and historical series, the long-term results suggest that the obliteration rate is significantly lower in embolized AVMs compared with nonembolized AVMs, also because of the fact that the combined treatment is applied to higher grade AVMs; the percentage of grade III-V AVMs was 58.6% and 48.8% for nonembolized AVMs.

Sign in / Sign up

Export Citation Format

Share Document