Delayed treatment of ruptured brain AVMs: is it ok to wait?

Optimal Timing of Microsurgical Treatment for Ruptured Arteriovenous Malformations: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

The timing of microsurgical treatment (MST) for ruptured brain arteriovenous malformations (bAVM) is a contentious issue in the literature. This study aimed to investigate the impact of MST timing on outcomes in patients with ruptured bAVMs, considering MST with and without preoperative endovascular treatment (EVT).

METHOD

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines, a comprehensive search was conducted across multiple databases, yielding 15 studies meeting the inclusion criteria. The timing was defined as the duration from the rupture of bAVM to the MST. The patients were divided into 4 different groups based on MST timing: <48 hours, <1 week, <2 weeks, and <1 month. The primary outcome was favorable outcome defined as a modified Rankin Scale score of 0 to 2 or a Glasgow Outcome Scale score of 4 to 5 in the last clinical follow-up. Secondary outcomes included periprocedural mortality and complete excision.

RESULTS

MST time >48 hours were associated with a significantly higher favorable outcome rate (odds ratio: 9.71, 95% Cl: 3.09-30.57, P < .01) and a lower mortality rate (OR: 0.15, 95% Cl: 0.02-0.88, P = .04) compared with MST timing ≤48 hours. After exclusion of patients who underwent MST with preoperative EVT, MST time >48 hours had a significantly higher rate of favorable outcome (OR: 9.39, 95% CI: 2.53-34.89, P < .01).

CONCLUSION

This meta-analysis suggests that delayed surgical intervention beyond 48 hours may be associated with improved favorable outcomes in patients who underwent MST with and without preoperative EVT for ruptured bAVMs.

Outcome of early versus late primary embolization in ruptured brain arteriovenous malformations

PURPOSE

To determine whether patients with a ruptured brain arteriovenous malformation (rBAVM) would benefit from an early embolization.

METHODS

rBAVM treated first by embolization between March 2002 and May 2022 were included. Embolization was defined early (Group 1) when performed within 10 days postbleeding. If later, embolization was considered late (Group 2). Demographic and rBAVM data were compared between the groups. High-risk bleeding components and reasons for deferring embolization were retrieved. Primary endpoint was rebleeding. Secondary endpoints were good functional outcome (FO, modified Rankin Scale mRS ≤ 2) and angiographic occlusion. Predictors of rebleeding and FO were determined by multivariate analysis.

RESULTS

105 patients were recruited (N = 34 in Group 1; N = 71 in Group 2). No rebleeding was noted before, during or after the first embolization session in the early embolization group. Late embolization depended on missed diagnosis and referral pattern. Eleven patients (10.5%) suffered a rebleeding, of whom N = 3 before embolization (only in Group 2), N = 5 periembolization (N = 2 at the second embolization session in Group 1) and N = 3 spontaneous more than 30 days postembolization. More high-risk components were embolized in Group 1 (19/34; 55.9 vs 17/71; 23.9%; p = .011). Rebleeding rates, FO at last FU (90.9% vs 74.3%) and occlusion rates (80.8% vs 88.5%) did not differ between the groups. Glasgow coma scale ≤ 8 predicted rebleeding, rebleeding correlated with poor FO.

CONCLUSION

Early embolization did prevent rebleeding. The overall rebleeding risk was linked to bleeding before late embolization and bleeding at the second embolization. Rebleeding predicted the final FO.

Influence of preoperative embolisation on resection of brain arteriovenous malformations: cohort study

PURPOSE

Preoperative endovascular embolisation is a widely used adjunct for the surgical treatment of brain arteriovenous malformations (AVMs). However, whether this improves completeness of AVM resection is unknown, as previous analyses have not adjusted for potential confounding factors. We aimed to determine if preoperative endovascular embolisation was associated with increased rate of complete AVM resection at first surgery, following adjustment for Spetzler-Martin grade items.

METHODS

We identified a cohort of all patients undergoing first ever AVM resection in a specialist neurosciences unit in the NHS Lothian Health Board region of Scotland between June 2004 and June 2022. Data was prospectively extracted from medical records. Our primary outcome was completeness of AVM resection. We determined the odds of complete AVM resection using binomial logistic regression with adjustment for Spetzler-Martin grading system items: maximum nidus diameter, eloquence of adjacent brain and the presence of deep venous drainage.

RESULTS

88 patients (median age 40y [IQR 19-53], 55% male) underwent AVM resection. 34/88 (39%) patients underwent preoperative embolisation and complete resection was achieved at first surgery in 74/88 (84%). Preoperative embolisation was associated with increased adjusted odds of complete AVM resection (adjusted odds ratio [aOR] 8.6 [95% confidence interval (95% CI) 1.7-67.7]; p = 0.017). The presence of deep venous drainage was associated with reduced chance of complete AVM resection (aOR 0.18 [95% CI 0.04-0.63]; p = 0.009).

CONCLUSIONS

Preoperative embolisation is associated with improved chances of complete AVM resection following adjustment for Spetzler-Martin grade, and should therefore be considered when planning surgical resection of AVMs.

Natural history and clinical manifestation of Pediatric Brain Arteriovenous Malformations

Brain arteriovenous malformations (bAVMs) are aberrant arteriovenous shunts through a vascular nidus with no intervening capillary beds. They are one of the commonest causes of spontaneous intracranial haemorrhage in children and may be associated with significant morbidity and mortality in cases of rupture. Treatment strategies include microsurgical resection, endovascular embolisation, stereotactic radiosurgery, multimodality treatment with a combination thereof, and particularly in high-grade bAVMs, conservative management. Clinicians involved in treating bAVMs need to have familiarity with the natural history pertaining to bAVMs in terms of risk of rupture, risk factors elevating rupture risk as well as understanding the clinical manifestations of bAVMs. This invited review serves to provide a synthesis on natural history and clinical presentation of bAVMs with particular focus in children to inform decision-making pertaining to management.

Most Promising Approaches to Improve Brain AVM Management: ARISE I Consensus Recommendations

Brain arteriovenous malformations (bAVMs) are complex, and rare arteriovenous shunts that present with a wide range of signs and symptoms, with intracerebral hemorrhage being the most severe. Despite prior societal position statements, there is no consensus on the management of these lesions. ARISE (Aneurysm/bAVM/cSDH Roundtable Discussion With Industry and Stroke Experts) was convened to discuss evidence-based approaches and enhance our understanding of these complex lesions. ARISE identified the need to develop scales to predict the risk of rupture of bAVMs, and the use of common data elements to perform prospective registries and clinical studies. Additionally, the group underscored the need for comprehensive patient management with specialized centers with expertise in cranial and spinal microsurgery, neurological endovascular surgery, and stereotactic radiosurgery. The collection of prospective multicenter data and gross specimens was deemed essential for improving bAVM characterization, genetic evaluation, and phenotyping. Finally, bAVMs should be managed within a multidisciplinary framework, with clinical studies and research conducted collaboratively across multiple centers, harnessing the collective expertise and centralization of resources.

Early Treatment of Ruptured Cerebral Arteriovenous Malformations: Analysis of Neurological Outcomes and Health Care Costs

BACKGROUND

The timing of surgical resection is controversial when managing ruptured arteriovenous malformations (AVMs) and varies considerably among centers.

OBJECTIVE

To retrospectively analyze clinical outcomes and hospital costs associated with delayed treatment in a ruptured cerebral AVM patient cohort.

METHODS

Patients undergoing surgical treatment for a ruptured cerebral AVM (January 1, 2015-December 31, 2020) were retrospectively analyzed. Patients who underwent emergent treatment of a ruptured AVM because of acute herniation were excluded, as were those treated >180 days after rupture. Patients were stratified by the timing of surgical intervention relative to AVM rupture into early (postbleed days 1-20) and delayed (postbleed days 21-180) treatment cohorts.

RESULTS

Eighty-seven patients were identified. The early treatment cohort comprised 75 (86%) patients. The mean (SD) length of time between AVM rupture and surgical resection was 5 (5) days in the early cohort and 73 (60) days in the delayed cohort ( P < .001). The cohorts did not differ with respect to patient demographics, AVM size, Spetzler-Martin grade, frequency of preoperative embolization, or severity of clinical presentation ( P ≥ .15). Follow-up neurological status was equivalent between the cohorts ( P = .65). The associated mean health care costs were higher in the delayed treatment cohort ($241 597 [$99 363]) than in the early treatment cohort ($133 989 [$110 947]) ( P = .02). After adjustment for length of stay, each day of delayed treatment increased cost by a mean of $2465 (95% CI = $967-$3964, P = .002).

CONCLUSION

Early treatment of ruptured AVMs was associated with significantly lower health care costs than delayed treatment, but surgical and neurological outcomes were equivalent.

Delayed versus immediate intervention of ruptured brain arteriovenous malformations: A case report

BACKGROUND

Brain arteriovenous malformations (bAVMs) remains one of the most prevalent causes of intracranial hemorrhage and stroke-like syndromes in the young adult population. Although it has been agreed upon that definitive treatment using either single or multi-modal approach is warranted for successful bAVM management, much debate still revolves regarding the optimal timing of definitive treatment.

CASE SUMMARY

In this report, we present a case of delayed, definitive endovascular treatment for ruptured bAVM in a 21-year-old female, 3 mo post-ictus. The bAVM, with a left pericallosal feeding artery and cortical draining veins, was successfully obliterated through embolization using the Onyx 18. On follow-up the patient has recommenced her daily activities and experiences only mild occasional headaches with mild motor deficits. The report leads to our review on an important issue regarding the optimal timing of ruptured bAVM definitive management and bring forward the current evidence available on delayed vs immediate definitive bAVM intervention. We also highlight current issues that need to be addressed for clearer guidelines on definitive therapy initiation.

CONCLUSION

Current treatment paradigms of ruptured bAVM remains elusive, with substantial heterogeneity in the current literature. A consensus on the definition of “acute” vs “delayed”, management goal, follow-up length and outcome parameters are required to support formation of a clear paradigm.

Curative embolization of ruptured pediatric cerebral arteriovenous malformations

INTRODUCTION

Embolization with the intention to cure has not been well studied in ruptured arteriovenous malformations (AVMs). Furthermore, the role of primary curative embolization of pediatric AVMs is uncertain. Hence, we aimed to characterize the safety and efficacy of curative embolization of ruptured pediatric AVMs and assess predictors of obliteration and complications.

METHODS

A retrospective analysis of all pediatric (≤18 years) patients who underwent curative embolization of ruptured AVMs was conducted in two institutions between 2010 and 2022. The efficacy (complete angiographic obliteration after the last embolization session), recurrence (radiological recurrence of the lesion after confirmed obliteration in follow-up imaging), and safety (procedure-related complications and mortality) of the procedure were evaluated.

RESULTS

Sixty-eight patients (38 females; mean age 12.4 ± 3.4 years) underwent a total of 109 embolization sessions. Median follow-up time was 18 months after embolization (ranged from 2 to 47 months). Complete angiographic obliteration was achieved in 42 patients (62%). In 30 patients (44%) the AVM was occluded with a single embolization session. Recurrence of a totally embolized lesion occurred in 9 patients (13%). Thirteen complications (11.9% of procedures) were observed, and no deaths were reported. A nidus size > 2 cm was the only independent predictor of complete obliteration (OR = 0.16; 95% CI 0.03 - 0.77; p = 0.030).

CONCLUSION

Embolization of pediatric ruptured AVMs with curative intent can achieve acceptable obliteration rates. However, recurrence after complete obliteration and procedure-related complications of curative embolization of these lesions cannot be ignored. Ruptured AVMs ≤ 2 cm are adequate to achieve complete obliteration with curative endovascular management.

Concurrent decompression and resection versus decompression with delayed resection of acutely ruptured brain arteriovenous malformations

OBJECTIVE

Brain arteriovenous malformations (bAVMs) most commonly present with rupture and intraparenchymal hemorrhage. In rare cases, the hemorrhage is large enough to cause clinical herniation or intractable intracranial hypertension. Patients in these cases require emergent surgical decompression as a life-saving measure. The surgeon must decide whether to perform concurrent or delayed resection of the bAVM. Theoretical benefits to concurrent resection include a favorable operative corridor created by the hematoma, avoiding a second surgery, and more rapid recovery and rehabilitation. The objective of this study was to compare the clinical and surgical outcomes of patients who had undergone concurrent emergent decompression and bAVM resection with those of patients who had undergone delayed bAVM resection.

METHODS

The authors conducted a 15-year retrospective review of consecutive patients who had undergone microsurgical resection of a ruptured bAVM at their institution. Patients presenting in clinical herniation or with intractable intracranial hypertension were included and grouped according to the timing of bAVM resection: concurrent with decompression (hyperacute group) or separate resection surgery after decompression (delayed group). Demographic and clinical characteristics were recorded. Groups were compared in terms of the primary outcomes of hospital and intensive care unit (ICU) lengths of stay (LOSs). Secondary outcomes included complete obliteration (CO), Glasgow Coma Scale score, and modified Rankin Scale score at discharge and at the most recent follow-up.

RESULTS

A total of 35/269 reviewed patients met study inclusion criteria; 18 underwent concurrent decompression and resection (hyperacute group) and 17 patients underwent emergent decompression only with later resection of the bAVM (delayed group). Hyperacute and delayed groups differed only in the proportion that underwent preresection endovascular embolization (16.7% vs 76.5%, respectively; p < 0.05). There was no significant difference between the hyperacute and delayed groups in hospital LOS (26.1 vs 33.2 days, respectively; p = 0.93) or ICU LOS (10.6 vs 16.1 days, respectively; p = 0.69). Rates of CO were also comparable (78% vs 88%, respectively; p > 0.99). Medical complications were similar in the two groups (33% hyperacute vs 41% delayed, p > 0.99). Short-term clinical outcomes were better for the delayed group based on mRS score at discharge (4.2 vs 3.2, p < 0.05); however, long-term outcomes were similar between the groups.

CONCLUSIONS

Ruptured bAVM rarely presents in clinical herniation requiring surgical decompression and hematoma evacuation. Concurrent surgical decompression and resection of a ruptured bAVM can be performed on low-grade lesions without compromising LOS or long-term functional outcome; however, the surgeon may encounter a more challenging surgical environment.

Endovascular treatment in the multimodality management of brain arteriovenous malformations: report of the Society of NeuroInterventional Surgery Standards and Guidelines Committee

BACKGROUND

The purpose of this review is to summarize the data available for the role of angiography and embolization in the comprehensive multidisciplinary management of brain arteriovenous malformations (AVMs METHODS: We performed a structured literature review for studies examining the indications, efficacy, and outcomes for patients undergoing endovascular therapy in the context of brain AVM management. We graded the quality of the evidence. Recommendations were arrived at through a consensus conference of the authors, then with additional input from the full Society of NeuroInterventional Surgery (SNIS) Standards and Guidelines Committee and the SNIS Board of Directors.

RESULTS

The multidisciplinary evaluation and treatment of brain AVMs continues to evolve. Recommendations include: (1) Digital subtraction catheter cerebral angiography (DSA)-including 2D, 3D, and reformatted cross-sectional views when appropriate-is recommended in the pre-treatment assessment of cerebral AVMs. (I, B-NR) . (2) It is recommended that endovascular embolization of cerebral arteriovenous malformations be performed in the context of a complete multidisciplinary treatment plan aiming for obliteration of the AVM and cure. (I, B-NR) . (3) Embolization of brain AVMs before surgical resection can be useful to reduce intraoperative blood loss, morbidity, and surgical complexity. (IIa, B-NR) . (4) The role of primary curative embolization of cerebral arteriovenous malformations is uncertain, particularly as compared with microsurgery and radiosurgery with or without adjunctive embolization. Further research is needed, particularly with regard to risk for AVM recurrence. (III equivocal, C-LD) . (5) Targeted embolization of high-risk features of ruptured brain AVMs may be considered to reduce the risk for recurrent hemorrhage. (IIb, C-LD) . (6) Palliative embolization may be useful to treat symptomatic AVMs in which curative therapy is otherwise not possible. (IIb, B-NR) . (7) The role of AVM embolization as an adjunct to radiosurgery is not well-established. Further research is needed. (III equivocal, C-LD) . (8) Imaging follow-up after apparent cure of brain AVMs is recommended to assess for recurrence. Although non-invasive imaging may be used for longitudinal follow-up, DSA remains the gold standard for residual or recurrent AVM detection in patients with concerning imaging and/or clinical findings. (I, C-LD) . (9) Improved national and international reporting of patients of all ages with brain AVMs, their treatments, side effects from treatment, and their long-term outcomes would enhance the ability to perform clinical trials and improve the rigor of research into this rare condition. (I, C-EO) .

CONCLUSIONS

Although the quality of evidence is lower than for more common conditions subjected to multiple randomized controlled trials, endovascular therapy has an important role in the management of brain AVMs. Prospective studies are needed to strengthen the data supporting these recommendations.

Endovascular Management of Hemorrhagic Stroke

Significant advances in endovascular neurosurgery tools, devices, and techniques are changing the approach to the management of acute hemorrhagic stroke. The endovascular treatment of intracranial aneurysms emerged in the early 1990s with Guglielmi detachable coils, and since then, it gained rapid popularity that surpassed open surgery. Stent-assisted coiling and balloon remodeling techniques have made the treatment of wide-necked aneurysms more durable. With the introduction of flow diverters and flow disrupters, many aneurysms with complex geometrics can now be reliably managed. Arteriovenous malformations and fistulae can also benefit from endovascular therapy by embolization using n-butyl cyanoacrylate (NBCA), Onyx, polyvinyl alcohol (PVA), and coils. In this article, we describe the role of endovascular treatment for the most common causes of intracerebral and subarachnoid hemorrhages, particularly ruptured aneurysms and vascular malformations.

Transpacific Aeromedical Evacuation for a Ruptured Brain Arteriovenous Malformation During the COVID-19 Pandemic

The COVID-19 pandemic has altered preexisting patient treatment algorithms and referral patterns, which has affected neurosurgical care worldwide. Brain arteriovenous malformations are complex vascular lesions that frequently present with intracerebral hemorrhage. Care for these patients is best performed at large medical centers by specialists with high volumes. The authors describe the care of a patient who presented in extremis to a resource-limited, community-sized military treatment facility (MTF) in Southeast Asia. In the MTF, the patient underwent emergent neurosurgical therapy. However, given newly implemented restrictions enacted to mitigate COVID-19 spread, local transfer for definitive care to a tertiary care facility was not possible. In order to attain definitive care for the patient, a transpacific aeromedical evacuation augmented with a critical care air transport team was utilized for transfer to a tertiary care, teaching hospital. This case demonstrates the safe treatment of a patient with hemorrhagic arteriovenous malformations and postoperative management under limited conditions in an MTF outside the CONUS. Given the unique circumstances and challenges the pandemic presented, the authors feel that this patient's outcome was only possible by leveraging all the capability military medicine has to offer.

Multimodal Assessment of Cerebral Autoregulation and Autonomic Function After Pediatric Cerebral Arteriovenous Malformation Rupture

BACKGROUND

Management after cerebral arteriovenous malformation (AVM) rupture aims toward preventing hemorrhagic expansion while maintaining cerebral perfusion to avoid secondary injury. We investigated associations of model-based indices of cerebral autoregulation (CA) and autonomic function (AF) with outcomes after pediatric cerebral AVM rupture.

METHODS

Multimodal neurologic monitoring data from the initial 3 days after cerebral AVM rupture were retrospectively analyzed in children (< 18 years). AF indices included standard deviation of heart rate (HRsd), root-mean-square of successive differences in heart rate (HRrmssd), low-high frequency ratio (LHF), and baroreflex sensitivity (BRS). CA indices include pressure reactivity index (PRx), wavelet pressure reactivity indices (wPRx and wPRx-thr), pulse amplitude index (PAx), and correlation coefficient between intracranial pressure pulse amplitude and cerebral perfusion pressure (RAC). Percent time of cerebral perfusion pressure (CPP) below lower limits of autoregulation (LLA) was also computed for each CA index. Primary outcomes were determined using Pediatric Glasgow Outcome Score Extended-Pediatrics (GOSE-PEDs) at 12 months and acquired epilepsy. Association of biomarkers with outcomes was investigated using linear regression, Wilcoxon signed-rank, or Chi-square.

RESULTS

Fourteen children were analyzed. Lower AF indices were associated with poor outcomes (BRS [p = 0.04], HRsd [p = 0.04], and HRrmssd [p = 0.00]; and acquired epilepsy (LHF [p = 0.027]). Higher CA indices were associated with poor outcomes (PRx [p = 0.00], wPRx [p = 0.00], and wPRx-thr [p = 0.01]), and acquired epilepsy (PRx [p = 0.02] and wPRx [p = 0.00]). Increased time below LLA was associated with poor outcome (percent time below LLA based on PRx [p = 0.00], PAx [p = 0.04], wPRx-thr [p = 0.03], and RAC [p = 0.01]; and acquired epilepsy (PRx [p = 0.00], PAx [p = 0.00], wPRx-thr [p = 0.03], and RAC [p = 0.01]).

CONCLUSIONS

After pediatric cerebral AVM rupture, poor outcomes are associated with AF and CA when applying various neurophysiologic model-based indices. Prospective work is needed to assess these indices of CA and AF in clinical decision support.

Acute surgical management of children with ruptured brain arteriovenous malformation

OBJECTIVE

Rupture of brain arteriovenous malformation (AVM) is the main etiology of intracerebral hemorrhage (ICH) in children. Ensuing intracranial hypertension is among the modifiable prognosis factors and sometimes requires emergency hemorrhage evacuation (HE). The authors aimed to analyze variables associated with HE in children with ruptured AVM.

METHODS

This study was a single-center retrospective analysis of children treated for ruptured AVM. The authors evaluated the occurrence of HE, its association with other acute surgical procedures (e.g., nidal excision, decompressive hemicraniectomy), and clinical outcome. Variables associated with each intervention were analyzed using univariable and multivariable models. Clinical outcome was assessed at 18 months using the ordinal King's Outcome Scale for Childhood Head Injury.

RESULTS

A total of 104 patients were treated for 112 episodes of ruptured AVM between 2002 and 2018. In the 51 children (45.5% of cases) who underwent HE, 37 procedures were performed early (i.e., within 24 hours after initial cerebral imaging) and 14 late. Determinants of HE were a lower initial Glasgow Coma Scale score (adjusted odds ratio [aOR] 0.83, 95% CI 0.71-0.97 per point increase); higher ICH/brain volume ratio (aOR 18.6, 95% CI 13-26.5 per percent increase); superficial AVM location; and the presence of a brain herniation (aOR 3.7, 95% CI 1.3-10.4). Concurrent nidal surgery was acutely performed in 69% of Spetzler-Martin grade I-II ruptured AVMs and in 25% of Spetzler-Martin grade III lesions. Factors associated with nidal surgery were superficial AVMs, late HE, and absent alteration of consciousness at presentation. Only 8 cases required additional surgery due to intracranial hypertension. At 18 months, overall mortality was less than 4%, 58% of patients had a favorable outcome regardless of surgical intervention, and 87% were functioning independently.

CONCLUSIONS

HE is a lifesaving procedure performed in approximately half of the children who suffer AVM rupture. The good overall outcome justifies intensive initial management.

Bringing high-grade arteriovenous malformations under control: clinical outcomes following multimodality treatment in children

OBJECTIVE

Brain arteriovenous malformations (AVMs) consist of dysplastic blood vessels with direct arteriovenous shunts that can hemorrhage spontaneously. In children, a higher lifetime hemorrhage risk must be balanced with treatment-related morbidity. The authors describe a collaborative, multimodal strategy resulting in effective and safe treatment of pediatric AVMs.

METHODS

A retrospective analysis of a prospectively maintained database was performed in children with treated and nontreated pediatric AVMs at the University of California, San Francisco, from 1998 to 2017. Inclusion criteria were age ≤ 18 years at time of diagnosis and an AVM confirmed by a catheter angiogram.

RESULTS

The authors evaluated 189 pediatric patients with AVMs over the study period, including 119 ruptured (63%) and 70 unruptured (37%) AVMs. The mean age at diagnosis was 11.6 ± 4.3 years. With respect to Spetzler-Martin (SM) grade, there were 38 (20.1%) grade I, 40 (21.2%) grade II, 62 (32.8%) grade III, 40 (21.2%) grade IV, and 9 (4.8%) grade V lesions. Six patients were managed conservatively, and 183 patients underwent treatment, including 120 resections, 82 stereotactic radiosurgery (SRS), and 37 endovascular embolizations. Forty-four of 49 (89.8%) high-grade AVMs (SM grade IV or V) were treated. Multiple treatment modalities were used in 29.5% of low-grade and 27.3% of high-grade AVMs. Complete angiographic obliteration was obtained in 73.4% of low-grade lesions (SM grade I-III) and in 45.2% of high-grade lesions. A periprocedural stroke occurred in a single patient (0.5%), and there was 1 treatment-related death. The mean clinical follow-up for the cohort was 4.1 ± 4.6 years, and 96.6% and 84.3% of patients neurologically improved or remained unchanged in the ruptured and unruptured AVM groups following treatment, respectively. There were 16 bleeding events following initiation of AVM treatment (annual rate: 0.02 events per person-year).

CONCLUSIONS

Coordinated multidisciplinary evaluation and individualized planning can result in safe and effective treatment of children with AVMs. In particular, it is possible to treat the majority of high-grade AVMs with an acceptable safety profile. Judicious use of multimodality therapy should be limited to appropriately selected patients after thorough team-based discussions to avoid additive morbidity. Future multicenter studies are required to better design predictive models to aid with patient selection for multimodal pediatric care, especially with high-grade AVMs.

Surgical strategies for management of pediatric arteriovenous malformation rupture: the role of initial decompressive craniectomy

INTRODUCTION

Arteriovenous malformations (AVMs) are a common cause of intracranial hemorrhage in children, which can result in elevated intracranial pressure (ICP) and cerebral edema. We sought to explore the role of initial decompressive craniectomy at time of rupture, followed by interval surgical AVM resection, compared to treatment with initial resection, in clinical outcomes and recovery in children.

METHODS

A retrospective chart review was conducted examining patients age 0-18 with AVM rupture between 2005 and 2018 who underwent resection for ruptured AVM either initially at presentation or underwent initial decompressive craniectomy followed by interval AVM resection. Clinical, radiographic, surgical, and outcome data were examined. Primary outcomes measured included functional status, AVM obliteration rate, AVM recurrence/residual, and re-hemorrhage.

RESULTS

Thirty-six cases were included; 28 (77.8%) underwent initial AVM resection, and 7 (19.4%) underwent initial decompressive craniectomy with interval resection. The mean time between craniectomy and resection was 66.9 days (SD 59.3). Patients undergoing initial decompressive craniectomy with interval resection were younger (mean age 6.1 vs. 9.8 years, p = 0.05) and had a higher mean hematoma volume (52.9 vs. 22.2 mL, p = 0.01), mean midline shift (5.1 vs. 2.1 mm, p = 0.01), and presence of cisternal effacement (p = 0.01). There were no statistically significant associations between surgical strategy and postoperative outcomes, including complications, radiographic outcomes, complete resection, residual, recurrence, and functional outcomes. Those treated by initial craniectomy followed by interval resection were associated with undergoing additional procedures.

CONCLUSIONS

Children presenting with AVM rupture who require emergent decompression may safely undergo emergent craniectomy with interval AVM resection and cranioplasty without additional risk of morbidity or mortality. This is reasonable in those with elevated intracranial pressure. This strategy may provide time for initial recovery and allow for natural degradation of the hematoma enhancing the plane for interval AVM resection, perhaps improving outcomes.

Long-term outcomes and prognostic predictors of 111 pediatric hemorrhagic cerebral arteriovenous malformations after microsurgical resection: a single-center experience

Comparison in pediatric hemorrhagic arteriovenous malformations (AVMs) to clarify the long-term neurological outcomes and prognostic predictors after surgical intervention was relatively rare, especially in the selection of surgical timing. The objective of this study was to elucidate these points. The authors retrospectively reviewed the pediatric hemorrhagic AVMs resected in their neurosurgical department between March 2010 and June 2017. The natural history was represented by rupture risk. Neurological outcome was assessed with the modified Rankin Scale (mRS) for children. Multivariate logistic regression analyses were used to assess the risk factors for disability (mRS > 2). The hemorrhagic early phase was defined as less than 30 days after bleeding. The corresponding prognosis of different surgical timing (early intervention or delayed intervention) was compared after propensity-score matching (PSM). A total of 111 pediatric hemorrhagic AVM patients were evaluated. The average patient age was 11.1 ± 4.0 years, with a mean follow-up of 4.3 ± 2.1 years. The annualized rupture risk was 9.3% for the pediatric hemorrhagic AVMs, and the annualized re-rupture risk was 9.8%. 7.2% of the patients had disabilities (mRS > 2) and 82.0% achieved neurological deficit-free (mRS < 2) at the last follow-up. Pre-treatment mRS (P = 0.042) and flow-related aneurysms (P = 0.039) were independent factors for long-term disability. In terms of short-term outcomes, early intervention was better than delayed intervention (P = 0.033), but the long-term outcomes were similar between the two groups (P = 0.367). Surgical intervention for pediatric hemorrhagic AVMs is recommended, most of the patients can achieve good neurological outcomes. Moreover, early surgical intervention is preferred after the initial hemorrhage.

Embolization of brain arteriovenous malformations with intent to cure: a systematic review

OBJECTIVE

Endovascular embolization has been established as an adjuvant treatment strategy for brain arteriovenous malformations (AVMs). A growing body of literature has discussed curative embolization for select lesions. The transition of endovascular embolization from an adjunctive to a definitive treatment modality remains controversial. Here, the authors reviewed the literature to assess the lesional characteristics, technical factors, and angiographic and clinical outcomes of endovascular embolization of AVMs with intent to cure.

METHODS

Electronic databases-Ovid MEDLINE, Ovid Embase, and PubMed-were searched for studies in which there was evidence of AVMs treated using endovascular embolization with intent to cure. The primary outcomes of interest were angiographic obliteration immediately postembolization and at follow-up. The secondary outcomes of interest were complication rates. Descriptive statistics were used to calculate rates and means.

RESULTS

Fifteen studies with 597 patients and 598 AVMs treated with intent-to-cure embolization were included in this analysis. Thirty-four percent of AVMs were Spetzler-Martin grade III. Complete obliteration immediately postembolization was reported in 58.3% of AVMs that had complete treatment and in 45.8% of AVMs in the entire patient cohort. The overall clinical complication rate was 24.1%. The most common complication was hemorrhage, occurring in 9.7% of patients. Procedure-related mortality was 1.5%.

CONCLUSIONS

While endovascular embolization with intent to cure can be an option for select AVMs, the reported complication rates appear to be increased compared with those in studies in which adjunctive embolization was the goal. Given the high complication rate related to a primary embolization approach, the risks and benefits of such a treatment strategy should be discussed among a multidisciplinary team. Curative embolization of AVMs should be considered an unanticipated benefit of such therapy rather than a goal.

Acute Subdural Hematomas in Ruptured Brain Arteriovenous Malformations: Association with Distal Flow-Related Aneurysms

PURPOSE

Non-traumatic acute subdural hematomas (SDH) are rare and have seldom been reported in ruptured brain arteriovenous malformations (BAVM). The aim of this study was to report the frequency of acute SDH in BAVM-related hemorrhage and to determine the relationship of SDHs with BAVM angioarchitectural features.

METHODS

This was a retrospective monocentric study of patients admitted for BAVM rupture between 2003 and 2017. Patients with rupture complicating or closely following partial embolization procedures were excluded. Univariate followed by multivariate logistic regression analysis was used to determine factors significantly and independently associated with SDHs and distal flow-related aneurysms.

RESULTS

A total of 181 patients with 188 BAVM ruptures admitted during the study period were included, eleven cases of acute SDH were identified (6%) and 2 cases of isolated SDH were found. The presence of a distal flow-related aneurysm was the only feature independently and significantly associated with SDH (odds ratio [OR] 8.1, 95% confidence interval, CI 1.9-34.5, P = 0.003). Distal flow-related aneurysms were associated with proximal flow-related aneurysms (OR 28, 95%CI 4.9-163.8, P < 0.001), were more frequent in infratentorial BAVMs (OR 3.7, 95%CI 1.3-10.2, P = 0.01) and more often found in cases of acute SDH (OR 16.9, 95%CI 3.6-79.6, P < 0.001) and subarachnoid hemorrhage (SAH) (OR 4.5, 95%CI 1.7-12.2, P = 0.003).

CONCLUSION

Ruptured BAVMs can rarely present with acute SDH and SDH in ruptured BAVMs are often associated with distal flow-related aneurysms. This finding may impact acute management of ruptured BAVMs with SDH by eliciting an emergent and thorough imaging work-up to identify distal flow-related aneurysm(s), in turn leading to treatment.