Effects of Preoperative Embolization on Spetzler–Martin Grade I and II Arteriovenous Malformations: A Propensity-Adjusted Analysis

OBJECT Resection is an appealing therapy for brain arteriovenous malformations (AVMs) because of its high cure rate, low complication rate, and immediacy, and has become the first-line therapy for many AVMs. To clarify safety, efficacy, and outcomes associated with AVM resection in the aftermath of A Randomized Trial of Unruptured Brain AVMs (ARUBA), the authors reviewed their experience with low-grade AVMs—the most favorable AVMs for surgery and the ones most likely to have been selected for treatment outside of ARUBA's randomization process. METHODS A prospective AVM registry was searched to identify patients with Spetzler-Martin Grade I and II AVMs treated using resection during a 16-year period. RESULTS Of the 232 surgical patients included, 120 (52%) presented with hemorrhage, 33% had Spetzler-Martin Grade I, and 67% had Grade II AVMs. Overall, 99 patients (43%) underwent preoperative embolization, with unruptured AVMs embolized more often than ruptured AVMs. AVM resection was accomplished in all patients and confirmed angiographically in 218 patients (94%). There were no deaths among patients with unruptured AVMs. Good outcomes (modified Rankin Scale [mRS] score 0–1) were found in 78% of patients, with 97% improved or unchanged from their preoperative mRS scores. Patients with unruptured AVMs had better functional outcomes (91% good outcome vs 65% in the ruptured group, p = 0.0008), while relative outcomes were equivalent (98% improved/unchanged in patients with ruptured AVMs vs 96% in patients with unruptured AVMs). CONCLUSIONS Surgery should be regarded as the “gold standard” therapy for the majority of low-grade AVMs, utilizing conservative embolization as a preoperative adjunct. High surgical cure rates and excellent functional outcomes in patients with both ruptured and unruptured AVMs support a dominant surgical posture for low-grade AVMS, with radiosurgery reserved for risky AVMs in deep, inaccessible, and highly eloquent locations. Despite the technological advances in endovascular and radiosurgical therapy, surgery still offers the best cure rate, lowest risk profile, and greatest protection against hemorrhage for low-grade AVMs. ARUBA results are influenced by a low randomization rate, bias toward nonsurgical therapies, a shortage of surgical expertise, a lower rate of complete AVM obliteration, a higher rate of delayed hemorrhage, and short study duration. Another randomized trial is needed to reestablish the role of surgery in unruptured AVM management.

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Microsurgical treatment of arteriovenous malformations in pediatric patients: the Boston Children's Hospital experience

Journal of Neurosurgery Pediatrics ◽

10.3171/2014.9.peds146 ◽

2015 ◽

Vol 15 (1) ◽

pp. 71-77 ◽

Cited By ~ 51

Author(s):

Bradley A. Gross ◽

Armide Storey ◽

Darren B. Orbach ◽

R. Michael Scott ◽

Edward R. Smith

Keyword(s):

Arteriovenous Malformations ◽

Neurological Complications ◽

Neurological Deficits ◽

Preoperative Embolization ◽

Recurrence Rates ◽

Microsurgical Treatment ◽

Obliteration Rate ◽

Microsurgical Resection ◽

Martin Grade ◽

Cerebral Avms

OBJECT Outcomes of microsurgical treatment of arteriovenous malformations (AVMs) in children are infrequently reported across large cohorts. METHODS The authors undertook a retrospective review of departmental and hospital databases to obtain the medical data of all patients up to 18 years of age who were diagnosed with cerebral AVMs. Demographic and AVM angioarchitectural characteristics were analyzed, and for the patients who underwent surgery, the authors also analyzed the estimated intraoperative blood loss, postoperative angiographically confirmed obliteration rates, and neurological complications and outcomes classified according to the modified Rankin Scale (mRS). RESULTS Of 117 children with cerebral AVMs, 94 underwent microsurgical resection (80%). Twenty (21%) of these 94 patients underwent adjunctive preoperative embolization. The overall postoperative angiographically confirmed obliteration rate was 94%. As part of a new protocol, the last 50 patients in this series underwent immediate perioperative angiography, improving the subsequent obliteration rate from 86% to 100% (p = 0.01). No other factors, such as a hemorrhagic AVM, size of the AVM, location, drainage, or Spetzler-Martin grade, had a statistically significant impact on the obliteration rate. Perioperative neurological deficits occurred in 17% of the patients, but the vast majority of these (77%) were predictable visual field cuts. Arteriovenous malformations that were hemorrhagic or located in noneloquent regions were each associated with lower rates of postoperative neurological complications (p = 0.05 and 0.002, respectively). In total, 94% of the children had good functional outcomes (mRS Scores 0–2), and these outcomes were significantly influenced by the mRS score on presentation before surgery (p = 0.01). A review of 1- and 5-year follow-up data indicated an overall annual hemorrhage rate of 0.3% and a recurrence rate of 0.9%. CONCLUSIONS Microsurgical resection of AVMs in children is associated with high rates of angiographically confirmed obliteration and low rates of significant neurological complications. Implementation of a protocol using perioperative angiography in this series led to complete radiographically confirmed obliteration of all AVMs, with low annual repeat hemorrhage and recurrence rates.

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Factors related to complete occlusion of arteriovenous malformations after gamma knife radiosurgery

Journal of Neurosurgery ◽

10.3171/jns.2000.93.supplement_3.0096 ◽

2000 ◽

Vol 93 (supplement_3) ◽

pp. 96-101 ◽

Cited By ~ 67

Author(s):

Jong Hee Chang ◽

Jin Woo Chang ◽

Yong Gou Park ◽

Sang Sup Chung

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Gamma Knife Radiosurgery ◽

Maximum Diameter ◽

Content Type ◽

Complete Occlusion ◽

Factors Associated ◽

Martin Grade ◽

Fine Print

Object. The authors sought to evaluate the effects of gamma knife radiosurgery (GKS) on cerebral arteriovenous malformations (AVMs) and the factors associated with complete occlusion. Methods. A total of 301 radiosurgical procedures for 277 cerebral AVMs were performed between December 1988 and December 1999. Two hundred seventy-eight lesions in 254 patients who were treated with GKS from May 1992 to December 1999 were analyzed. Several clinical and radiological parameters were evaluated. Conclusions. The total obliteration rate for the cases with an adequate radiological follow up of more than 2 years was 78.9%. In multivariate analysis, maximum diameter, angiographically delineated shape of the AVM nidus, and the number of draining veins significantly influenced the result of radiosurgery. In addition, margin radiation dose, Spetzler—Martin grade, and the flow pattern of the AVM nidus also had some influence on the outcome. In addition to the size, topography, and radiosurgical parameters of AVMs, it would seem to be necessary to consider the angioarchitectural and hemodynamic aspects to select proper candidates for radiosurgery.

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Techniques of Onyx Embolization of Arteriovenous Malformation: 2-Dimensional Operative Video

Operative Neurosurgery ◽

10.1093/ons/opab061 ◽

2021 ◽

Author(s):

Kathryn M Wagner ◽

Visish M Srinivasan ◽

Peter Kan

Keyword(s):

Informed Consent ◽

Surgical Resection ◽

Arteriovenous Malformations ◽

Preoperative Embolization ◽

Great Care ◽

Endovascular Techniques ◽

Definitive Therapy ◽

Feeding Vessels ◽

Multiple Feeding ◽

Staged Treatment

Abstract Advances in endovascular techniques and tools have allowed for treatment of complex arteriovenous malformations (AVMs), which historically may have posed unacceptable risk for open surgical resection. Endovascular treatment may be employed as an adjunct to surgical resection or as definitive therapy. Improvements in embolization materials have made endovascular AVM treatment safer for patients and useful across a variety of lesions. While many techniques are employed for transarterial AVM embolization, the essential tenets apply to all procedures: (1) great care should be taken to cannulate only vessels directly supplying the lesion, and not en passage vessels, prior to injecting embolisate; (2) embolisate should travel into the nidus, but not into the draining veins; (3) embolistate reflux proximal to the microcatheter should be avoided. There are several techniques that accomplish these goals, including the plug and push method, or using a balloon to prevent embolisate reflux. We use controlled injection of liquid Onyx (Medtronic), with increasing pressure over multiple injections pushing the embolisate forward into the AVM. This is repeated in multiple feeding vessels to decrease or eliminate supply to the AVM. Here, we present a 36-yr-old female with a right parietal AVM discovered on workup of headaches. After informed consent was obtained, she underwent preoperative embolization using this technique prior to uncomplicated surgical resection. The video shows the endovascular Onyx embolization of multiple feeding vessels over staged treatment.

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Prevalence and characteristics of brain arteriovenous malformations in hereditary hemorrhagic telangiectasia: a systematic review and meta-analysis

Journal of Neurosurgery ◽

10.3171/2016.7.jns16847 ◽

2017 ◽

Vol 127 (2) ◽

pp. 302-310 ◽

Cited By ~ 20

Author(s):

Waleed Brinjikji ◽

Vivek N. Iyer ◽

Christopher P. Wood ◽

Giuseppe Lanzino

Keyword(s):

Systematic Review ◽

Hereditary Hemorrhagic Telangiectasia ◽

Arteriovenous Malformations ◽

Clinical Presentation ◽

Meta Analysis ◽

Prevalence Rates ◽

Brain Avm ◽

Martin Grade ◽

Cerebral Avms ◽

Brain Avms

OBJECTIVEPatients with hereditary hemorrhagic telangiectasia (HHT) are known to suffer from high rates of cerebral arteriovenous malformations (AVMs). The authors performed a systematic review and meta-analysis of the literature examining prevalence rates, characteristics, and clinical presentation of cerebral AVMs in the HHT population.METHODSTo identify studies on AVM prevalence and characteristics in the HHT population, 4 databases (MEDLINE, EMBASE, Scopus and Web of Science) were searched by a reference librarian with over 30 years experience in systematic reviews and meta-analysis. The search period was January 1, 1990–March 2016. The following search terms were used: hereditary hemorrhagic telangiectasia, Osler-Weber-Rendu syndrome, AVM, brain AVM, arteriovenous malformation, arteriovenous fistula, prevalence, and epidemiology. The authors identified studies that examined the prevalence rates, characteristics, and clinical presentation of cerebral AVMs in patients with HHT. They assessed overall AVM prevalence rates as well as prevalence rates by age, sex, HHT type, and country/region. They also systematically reviewed the characteristics of AVMs, including rupture status, location, clinical presentation, angioarchitecture, and Spetzler-Martin grade. Data were analyzed using a random-effects meta-analysis model.RESULTSThirty-nine studies were included in this meta-analysis. Thirty studies examined brain AVM prevalence rates in various HHT patient populations, and 18 studies examined AVM clinical and angiographic characteristics (9 studies examined both prevalence rates and AVM characteristics). The prevalence of brain AVMs in HHT patients was 10.4% (95% CI 7.9%–13.0%) with no significant difference between males (8.5%, 95% CI 4.9%–12.0%) and females (11.0%, 95% CI 5.9%–16.1%). Patients with HHT Type 1 (HHT1) had a significantly higher brain AVM prevalence (13.4%, 95% CI 9.5%–17.4%) compared with those with HHT Type 2 (HHT2) (2.4%, 95% CI 1.0%–3.8%) (p < 0.0001). In 55.2% (95% CI 38.3%–72.1%) of cases, the AVMs were symptomatic. Spetzler-Martin grade was 2 or less in 86.9% (95% CI 67.5%–95.2%) of patients.CONCLUSIONSThe prevalence of brain AVMs in the HHT population is about 10%. HHT1 patients are significantly more likely to have brain AVMs than HHT2 patients. Most AVMs in the HHT population are symptomatic. The Spetzler-Martin grade for these lesions is 2 or less in nearly 90% of patients.

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The safety profile and angioarchitectural changes after acute targeted embolization of ruptured arteriovenous malformations

Journal of Neurosurgery ◽

10.3171/2020.9.jns201558 ◽

2021 ◽

pp. 1-10

Author(s):

Ann Mansur ◽

Alex Kostynskyy ◽

Timo Krings ◽

Ronit Agid ◽

Ivan Radovanovic ◽

...

Keyword(s):

Arteriovenous Malformations ◽

Demographic Variables ◽

Delayed Treatment ◽

Kaplan Meier ◽

Complete Obliteration ◽

Management Paradigms ◽

Weak Points ◽

Martin Grade ◽

Logistical Regression Analysis

OBJECTIVE The aim of this study was to 1) compare the safety and efficacy of acute targeted embolization of angiographic weak points in ruptured brain arteriovenous malformations (bAVMs) versus delayed treatment, and 2) explore the angioarchitectural changes that follow this intervention. METHODS The authors conducted a retrospective analysis of a prospectively acquired database of ruptured bAVMs. Three hundred sixteen patients with ruptured bAVMs who presented to the hospital within 48 hours of ictus were included in the analysis. The first analysis compared clinical and functional outcomes of acutely embolized patients to those with delayed management paradigms. The second analysis compared these outcomes of patients with acute embolization to those with angiographic targets who did not undergo acute embolization. Finally, a subset of 20 patients with immediate postembolization angiograms and follow-up angiograms within 6 weeks of treatment were studied to determine the angioarchitectural changes after acute targeted embolization. Kaplan-Meier curves for survival between the groups were devised. Multivariate logistical regression analysis was conducted. RESULTS There were three deaths (0.9%) and an overall rerupture rate of 4.8% per year. There was no statistical difference in demographic variables, mortality, and rerupture rate between patients with acute embolization and those with delayed management. Patients with acute embolization were more likely to present functionally worse (46.9% vs 69.8%, modified Rankin Scale score 0–2, p = 0.018) and to require an adjuvant therapy (71.9% vs 26.4%, p < 0.001). When comparing acutely embolized patients to those nonacutely embolized angiographic targets, there was a significant protective effect of acute targeted therapy on rerupture rate (annual risk 1.2% vs 4.3%, p = 0.025) and no difference in treatment complications. Differences in the survival curves for rerupture were statistically significant. Multivariate analyses significantly predicted lower rerupture in acute targeted treatment and higher rerupture in those with associated aneurysms, deep venous anatomy, and higher Spetzler-Martin grade. All patients with acute embolization experienced complete obliteration of the angiographic weak point with various degrees of resolution of the nidus; however, some had spontaneous recurrence of their bAVM, while others had spontaneous resolution over time. No patients developed new angiographic weak points. CONCLUSIONS This study demonstrates that acute targeted embolization of angiographic weak points, particularly aneurysms, is technically safe and protective in the early phase of recovery from ruptured bAVMs. Serial follow-up imaging is necessary to monitor the evolution of the nidus after targeted and definitive treatments. Larger prospective studies are needed to validate these findings.

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55 Spetzler–Martin Grade IV and V Arteriovenous Malformations

Decision Making in Neurovascular Disease ◽

10.1055/b-0038-162184 ◽

2018 ◽

Keyword(s):

Arteriovenous Malformations ◽

Martin Grade

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Gamma Knife surgery for pediatric arteriovenous malformations: a 25-year retrospective study

Journal of Neurosurgery Pediatrics ◽

10.3171/2012.8.peds1241 ◽

2012 ◽

Vol 10 (5) ◽

pp. 445-450 ◽

Cited By ~ 29

Author(s):

Eduard B. Dinca ◽

Patricia de Lacy ◽

John Yianni ◽

Jeremy Rowe ◽

Matthias W. R. Radatz ◽

...

Keyword(s):

Arteriovenous Malformations ◽

Lesion Volume ◽

Bleeding Rate ◽

Patients Âgés ◽

Obliteration Rate ◽

Telephone Interviews ◽

Presenting Symptoms ◽

Martin Grade ◽

The Mean

Object The authors present their 25-year experience in treating pediatric arteriovenous malformations (AVMs) to allow comparisons with other historic studies and data in adults. Methods Data were collected from a prospectively maintained departmental database selected for age and supplemented by case note review and telephone interviews as appropriate. Results Three hundred sixty-three patients, ages 1–16 years (mean ± SD, 12 ± 3.2 years), underwent 410 treatments; 4 had planned 2-stage treatments and 43 were retreated subsequent to an initial partial response. Fifty-eight percent received general anesthesia for the procedure. Sixteen percent had previously undergone embolization. The most common presenting symptoms were as follows: hemorrhage (80.2%), epilepsy (8.3%; overall seizure prevalence 19.9%), and migrainous headaches (6.3%). Only 0.28% of the AVMs were incidental findings. The mean lesion volume was 3.75 ± 5.3 cm3 (range 0.01–32.8 cm3), with a median Spetzler-Martin grade of III (range I–V). The mean peripheral (therapeutic) dose was 22.7 ± 2.3 Gy (range 15–25 Gy), corresponding to a mean maximum dose of 43.6 ± 6 Gy (range 25–51.4 Gy). The obliteration rate was 71.3% in patients who received one treatment and 62.5% for retreated patients, with a mean obliteration time of 32.4 and 79.6 months, respectively. The overall obliteration rate was 82.7%. No follow-up data are as yet available for the 4 patients who underwent the staged treatments. Only 4 patients received peripheral doses below 20 Gy, and the AVM was obliterated in 3 of these patients. The other patients received 20, 22.5, or 25 Gy and had obliteration rates of 82.6%, 77.7%, and 86.3%, respectively. The bleeding rate postradiosurgery was 2.2%, and the cumulative complication rate was 3.6%, with radionecrosis being the most common complication (1.1%). Conclusions Surprisingly, there was no correlation (p = 0.43) between outcome and radiosurgical dose when that dose was between 20 and 25 Gy, thus suggesting that the lower of these 2 doses may be effective. Radiosurgery for pediatric AVM is safe and effective.

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Surgical Management Of Posterior Fossa Arteriovenous Malformations

Operative Neurosurgery ◽

10.1227/01.neu.0000204641.38419.2d ◽

2006 ◽

Vol 58 (suppl_4) ◽

pp. ONS-189-ONS-201 ◽

Cited By ~ 6

Author(s):

John Sinclair ◽

Michael E. Kelly ◽

Gary K. Steinberg

Keyword(s):

Stereotactic Radiosurgery ◽

Surgical Resection ◽

Posterior Fossa ◽

Arteriovenous Malformations ◽

Cranial Nerves ◽

Venous Drainage ◽

Cerebellar Nuclei ◽

Preoperative Embolization ◽

Frameless Stereotaxy ◽

Microsurgical Resection

Abstract Objective: Arteriovenous malformations (AVMs) involving the cerebellum and brainstem are relatively rare lesions that most often present clinically as a result of a hemorrhagic episode. Although these AVMs were once thought to have a more aggressive clinical course in comparison with supratentorial AVMs, recent autopsy data suggests that there may be little difference in hemorrhage rates between the two locations. Although current management of these lesions often involves preoperative embolization and stereotactic radiosurgery, surgical resection remains the treatment of choice, conferring immediate protection to the patient from the risk of future hemorrhage. Methods: Most symptomatic AVMs that involve the cerebellum and the pial or ependymal surfaces of the brainstem are candidates for surgical resection. Preoperative angiography and magnetic resonance imaging studies are critical to determine suitability for resection and choice of operative exposure. In addition to considering the location of the nidus, arterial supply, and predominant venous drainage, the surgical approach must also be selected with consideration of the small confines of the posterior fossa and eloquence of the brainstem, cranial nerves, and deep cerebellar nuclei. Results: Since the 1980s, progressive advances in preoperative embolization, frameless stereotaxy, and intraoperative electrophysiologic monitoring have significantly improved the number of posterior fossa AVMs amenable to microsurgical resection with minimal morbidity and mortality. Conclusion: Future improvements in endovascular technology and stereotactic radiosurgery will likely continue to increase the number of posterior fossa AVMs that can safely be removed and further improve the clinical outcomes associated with microsurgical resection.

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