Updates in arteriovenous malformation management: the post-ARUBA era

Rapid and Significant Angioarchitectural Changes in the Carotid Artery and Its Branches After Endovascular Treatment of Acute Hemorrhage Due to a Cerebral Arteriovenous Malformation

INTRODUCTION

Cerebral arteriovenous malformations (CAVMs) are rare, with an estimated prevalence of 0.01%. Symptoms typically present in adults under 40, often beginning with hemorrhage in 61% of cases. The annual risk of hemorrhage is between 2-4%, with a mortality rate of 10%, and 50% of survivors may experience permanent neurological deficits. Embolization can induce changes in the angioarchitecture of the affected vessels. Our case uniquely demonstrates a morphological alteration in the carotid artery (CA) and its primary branches, associated with the presence of a CAVM. Detailed Case Presentation: A 52-year-old patient presented to the Emergency Department with weakness, shortness of breath, dizziness, nausea, and vomiting that began earlier that morning. Clinical and radiological evaluations suggested acute bleeding from a ruptured CAVM. The patient was admitted for digital subtraction angiography (DSA) and potential embolization. DSA confirmed the presence of a CAVM, supplied by the middle meningeal and occipital arteries, with distortion of the left CA angioarchitecture. Selective catheterization and embolization using Onyx 18 were successfully performed. After receiving supportive treatment, the patient was discharged in good condition. A follow-up CT scan three months later showed complete resolution of the brain pathologies. A repeat angiogram revealed no recanalization of the CAVM, with normalization of the CA and its branches. The patient is currently asymptomatic.

CONCLUSIONS

Detection of pathological changes in the head and neck arteries linked to CAVM can predict rupture risk and complicate endovascular access. Identifying these changes early warrants consideration of interventions to prevent hemorrhage, though alternative access routes or strategies may be needed for safe, effective treatment.

Surgical Results with Low-Grade Arteriovenous Malformations : A Single Center 14-Year Experience

OBJECTIVE

Advancements in AVM surgical techniques for cerebral arteriovenous malformation (AVM) underscore its efficacy. Our research aims to showcase the positive outcomes of treating low-grade AVMs surgically, focusing on safety and effectiveness.

METHODS

We retrospectively reviewed 55 patients (36 males and 19 females; average age 37.4 years) with Spetzler-Martin (S-M) grade 1 and 2 AVMs who underwent surgical resection between January 2009 and December 2022.

RESULTS

In our study, 55 patients with S-M grade 1 and 2 AVMs underwent surgical resection, evenly divided between grades 1 (50.9%) and 2 (49.1%). Intracranial hemorrhage was the primary symptom in 74.5% of cases. Pre-operative Glasgow coma scale (GCS) scores revealed 69.1% of patients scored above 13, with 18% below 8. Successful resection was achieved in 87.3%. Postoperatively, 95.5% of ruptured and 90.9% of unruptured AVM patients showed lower or same modified Rankin scale scores. Poorer outcomes were significantly linked to lower GCS scores and intranidal/flow-related aneurysms through multivariate logistic regression. Postoperative seizures noted in nine patients, were exclusive to the ruptured AVM group.

CONCLUSION

Our findings indicate surgical resection as a beneficial treatment for low-grade AVMs, yielding high cure rates and positive functional outcomes in both ruptured and unruptured cases. Preoperative GCS scores and the presence of associated aneurysms are predictive of postoperative functional status. Additionally, managing postoperative seizures effectively is key to enhancing prognosis.

Risk of intracranial hemorrhage in brain arteriovenous malformations: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Brain arteriovenous malformations (bAVMs) carry a risk of hemorrhage. We aim to identify factors associated with subsequent hemorrhages.

METHODS

Systematic searches were conducted across the ScienceDirect, Medline, and Cochrane databases. Assessed risk factors included bAVM size, bAVM volume, hemorrhage and seizure presentations, presence of deep venous drainage, deep-seated bAVMs, associated aneurysms, and Spetzler-Martin grade. Subgroup analyses were conducted on prior treatments, hemorrhage presentation, AVM size, and type of management.

RESULTS

The meta-analysis included 8 cohort studies and 2 trials, with 4,240 participants. Initial hemorrhage presentation (HR 2.41; 95% CI 1.94-2.98; p < 0.001), any deep venous drainage (HR 1.52; 95% CI 1.09-2.13; p = 0.01), and associated aneurysms (HR 1.78; 95% CI 1.41-2.23; p < 0.001) increased secondary hemorrhage risk. Conversely, higher Spetzler-Martin grades (HR 0.77; 95% CI 0.68-0.87; p < 0.001) and larger malformation volumes (HR 0.87; 95% CI 0.76-0.99; p = 0.04) reduced risk. Subgroups showed any deep venous drainage in patients without prior treatment (HR 1.64; 95% CI 1.25-2.15; p < 0.001), bAVM > 3 cm (HR 1.79; 95% CI 1.15-2.78; p = 0.01), and multimodal interventions (HR 1.69; 95% CI 1.12-2.53; p = 0.01) increased risk. The reverse effect was found for patients initially presented without hemorrhage (HR 0.79; 95% CI 0.67-0.93; p = 0.01). Deep bAVM was a risk factor in > 3 cm cases (HR 2.72; 95% CI 1.61-4.59; p < 0.001) and multimodal management (HR 2.77; 95% CI 1.66-4.56; p < 0.001). Kaplan-Meier analysis revealed increased hemorrhage risk for initial hemorrhage presentation, while cumulative survival was higher in intervened patients over 72 months.

CONCLUSION

Significant risk factors for bAVMs hemorrhage include initial hemorrhage, any deep venous drainage, and associated aneurysms. Deep venous drainage involvement is a risk factor in cases without prior treatment, those with bAVM > 3 cm, and cases managed with multimodal interventions. Deep bAVM involvement also emerges as a risk factor in cases > 3 cm and those managed with multimodal approaches.

Trends in AVM-Associated Intracranial Hemorrhage in the United States, 2000-2019

This cross-sectional study examines whether there has been a significant change in the annual incidence of arteriovenous malformation (AVM)–associated intracranial hemorrhage among US adults over the past 2 decades.

Worldwide Research Trends on Transvenous Embolization of Brain Arteriovenous Malformations: A Bibliometric and Visualized Study

BACKGROUND

Transvenous embolization (TVE) of brain arteriovenous malformations (bAVMs) is an emerging endovascular technique that has shown high cure rates in selected cases. The rationale of our study was to determine authorship and worldwide institutional trends and contributions to the knowledge in this topic.

METHODS

Web of Science database was used. A total of 63 articles were included based on predefined inclusion criteria, which were manually reviewed. The bibliometric analysis involved the use of quantitative bibliometric indicators and network analysis with co-authorship and co-occurrence of terms, which were performed using the bibliometrix package in R and VOSviewer, respectively.

RESULTS

The first article was published in 2010, with the largest number of articles published in 2022 (10 articles). The average number of citations per document was 11.38, and the annual growth rate was 14.35%. The top 10 authors with the most scientific production on TVE of bAVMs were from France, and the most cited study was published by Iosif C in 2015, followed by Consoli A in 2013, and Chen CJ in 2018. Journal of Neurointerventional Surgery was the journal with the most articles published. The most commonly used keywords were dural arteriovenous fistula, Onyx, vascular disorders, and neurological surgery around 2016, and intervention around 2021.

CONCLUSIONS

TVE of bAVMs is an emerging technique. Our search identified some scientific articles, without randomized clinical trials, but many case series from single institutions. French and German institutions are the pioneers in the field, and further research is required in specialized endovascular centers.

Multi-Stage Treatment for Spetzler-Martin Grades III, IV, and V Arteriovenous Malformations: Preoperative Embolization and Microsurgical Resection in a Consecutive Series of 250 Patients

PURPOSE

The treatment of high-grade brain AVMs is challenging and has no guidelines available to date. This study was aimed at reporting the experience of two centers in treating these AVMs through a multi-stage approach consisting of preoperative embolization and microsurgical resection.

METHODS

A retrospective review was performed for 250 consecutive patients with a diagnosis of high-grade brain AVM (Spetzler-Martin grades III, IV, and V) treated in two centers in Germany between January 1989 and February 2023. The analyzed data included demographic, clinical, morphological, and neurological data.

RESULTS

A total of 150 cases (60%) were classified as Spetzler-Martin grade III, 82 cases (32.8%) were classified as grade IV, and 18 cases (7.2%) were classified as grade V. Eighty-seven cases (34.8%) presented with hemorrhage. The devascularization percentages achieved were <50% in 24 (9.6%), 50-80% in 55 (22%), and >80% in 171 (68.4%) cases. The average number of sessions was 5.65 ± 5.50 and 1.11 ± 0.32 endovascular and surgical procedures, respectively, and did not significantly differ by rupture status. Death or dependency (mRS score ≥ 3) after the last follow-up was observed in 18.8% of patients and was significantly associated with age > 80 years and poor baseline neurological condition. The complete resection rate was 82.3% and was significantly associated with age > 80 years, large nidus, and deep venous drainage. Permanent disabling neurological deficit after at least 3 months of follow-up was diagnosed in 13.2% of patients and was significantly associated with age > 80 years and infratentorial locations.

CONCLUSION

A multi-stage treatment for high-grade AVMs is feasible for selected cases but comes at a functional cost. The devascularization percentage was not associated with the investigated outcomes. Age > 80 years was associated with poor safety and effectiveness outcomes; consequently, this treatment should be offered only in exceptional circumstances.

Contralateral transfalcine approach for resection of right medial frontal AVM

Brain arteriovenous malformations (AVMs) are high flow vascular lesions that can cause significant morbidity and mortality [1-6]. We present a case of a 23-year-old woman who initially presented to an outside institution with a ruptured right medial frontal Spetzler Martin grade II AVM. An EVD was placed and a diagnostic angiogram with partial embolization was performed. She was then transferred to our institution two months post rupture for further care. On arrival, she was trached with eyes opening to voice and localizing in bilateral upper extremities and withdrawing in bilateral lower extremities. Diagnostic angiogram demonstrated arterial supply from the right pericallosal and callosomarginal artery, right posterior cerebral artery callosomarginal branch, distal left anterior cerebral artery (ACA) branches with venous drainage via a cortical vein to the superior sagittal sinus. The patient underwent preoperative embolization of the ACA feeders followed by a contralateral interhemispheric transfalcine approach. An interhemispheric dissection was performed down to the corpus callosum and AVM feeders and draining veins were identified. The falx was then incised to expose the right medial frontal lobe. The AVM was circumferentially dissected and resected. Postoperative imaging demonstrated complete resection of the AVM. She remained at her neurological baseline immediately postoperatively and was discharged to inpatient rehab. The patient made a remarkable recovery and at three months follow up, she no longer required a tracheostomy and was neurologically intact with no complaints except for mild memory difficulties. In this video, we demonstrate the step-by-step surgical technique and review the benefits of the contralateral transfalcine approach for resection of a ruptured right medial frontal Spetzler Martin grade II AVM. The patient consented to the procedure and to the publication of her imaging in this surgical video.

Endovascular treatment of brain arteriovenous malformations: clinical outcomes of patients included in the registry of a pragmatic randomized trial

OBJECTIVE

The role of endovascular treatment in the management of patients with brain arteriovenous malformations (AVMs) remains uncertain. AVM embolization can be offered as stand-alone curative therapy or prior to surgery or stereotactic radiosurgery (SRS) (pre-embolization). The Treatment of Brain AVMs Study (TOBAS) is an all-inclusive pragmatic study that comprises two randomized trials and multiple registries.

METHODS

Results from the TOBAS curative and pre-embolization registries are reported. The primary outcome for this report is death or dependency (modified Rankin Scale [mRS] score > 2) at last follow-up. Secondary outcomes include angiographic results, perioperative serious adverse events (SAEs), and permanent treatment-related complications leading to an mRS score > 2.

RESULTS

From June 2014 to May 2021, 1010 patients were recruited in TOBAS. Embolization was chosen as the primary curative treatment for 116 patients and pre-embolization prior to surgery or SRS for 92 patients. Clinical and angiographic outcomes were available in 106 (91%) of 116 and 77 (84%) of 92 patients, respectively. In the curative embolization registry, 70% of AVMs were ruptured, and 62% were low-grade AVMs (Spetzler-Martin grade I or II), while the pre-embolization registry had 70% ruptured AVMs and 58% low-grade AVMs. The primary outcome of death or disability (mRS score > 2) occurred in 15 (14%, 95% CI 8%-22%) of the 106 patients in the curative embolization registry (4 [12%, 95% CI 5%-28%] of 32 unruptured AVMs and 11 [15%, 95% CI 8%-25%] of 74 ruptured AVMs) and 9 (12%, 95% CI 6%-21%) of the 77 patients in the pre-embolization registry (4 [17%, 95% CI 7%-37%] of 23 unruptured AVMs and 5 [9%, 95% CI 4%-20%] of 54 ruptured AVMs) at 2 years. Embolization alone was confirmed to occlude the AVM in 32 (30%, 95% CI 21%-40%) of the 106 curative attempts and in 9 (12%, 95% CI 6%-21%) of 77 patients in the pre-embolization registry. SAEs occurred in 28 of the 106 attempted curative patients (26%, 95% CI 18%-35%, including 21 new symptomatic hemorrhages [20%, 95% CI 13%-29%]). Five of the new hemorrhages were in previously unruptured AVMs (n = 32; 16%, 95% CI 5%-33%). Of the 77 pre-embolization patients, 18 had SAEs (23%, 95% CI 15%-34%), including 12 new symptomatic hemorrhages [16%, 95% CI 9%-26%]). Three of the hemorrhages were in previously unruptured AVMs (3/23; 13%, 95% CI 3%-34%).

CONCLUSIONS

Embolization as a curative treatment for brain AVMs was often incomplete. Hemorrhagic complications were frequent, even when the specified intent was pre-embolization before surgery or SRS. Because the role of endovascular treatment remains uncertain, it should preferably, when possible, be offered in the context of a randomized trial.

Stroke in the young

PURPOSE OF REVIEW

The purpose of this review is to review recent findings regarding stroke epidemiology, etiologies, and treatment in children and young adults.

RECENT FINDINGS

Incidence in young adults is increasing, and incidence, recurrence, and survival is worse in patients with cryptogenic stroke and in developing countries. Careful consideration of patent foramen ovale closure is now recommended in young adults with cryptogenic stroke. Thrombectomy has recently been extended to carefully selected children with acute ischemic stroke, and two recent publications strongly suggest that it can be beneficial for children. Sickle cell is also an important global contributor to stroke burden, but hydroxyurea can be a cost effective medication for stroke prevention in children. Recent advances in genetic testing and treatments may improve outcomes for patients with monogenic causes of stroke, such as deficiency of adenosine deaminase 2, hemophilia, and Fabry's disease.

SUMMARY

Stroke in children and young adults is a morbid disease responsible for enormous indirect societal costs and a high burden of years with disability per affected patient. Recent advances have improved access to care for children with large vessel occlusion and adults with rare causes of stroke. Future research may bring effective treatments for other monogenic causes of stroke as well as increasing access to hyperacute therapies for young stroke patients.

Microsurgery versus Microsurgery With Preoperative Embolization for Brain Arteriovenous Malformation Treatment: A Systematic Review and Meta-analysis

BACKGROUND

Preoperative embolization has traditionally been regarded as a safe and effective adjunct to microsurgical treatment of brain arteriovenous malformations (bAVM). However, there is currently no high-level evidence to ascertain this presumption.

OBJECTIVE

To compare the outcomes of microsurgery (MS) vs microsurgery with preoperative embolization (E + MS) in patients with bAVM through systematic review.

METHODS

We searched MEDLINE, PubMed, and Embase. The primary outcome was bAVM obliteration. Secondary outcomes were intraoperative bleeding (mL), complications, worsened modified Rankin Scale (mRS), and mortality. The pooled proportions of outcomes were calculated through the logit transformation method. The odds ratio (OR) of categorical data and mean difference of continuous data were estimated through the Mantel-Haenszel and the inverse variance methods, respectively.

RESULTS

Thirty-two studies met the eligibility criteria. One thousand eight hundred twenty-eight patients were treated by microsurgery alone, and 1088 were treated by microsurgery with preoperative embolization, respectively. The meta-analysis revealed no significant difference in AVM obliteration (94.1% vs 95.6%, OR = 1.15 [0.63-2.11], P = .65), mortality (1.7% vs 2%, OR = 0.88 [0.30-2.58], P = .82), procedural complications (18.2% vs 27.2%, OR = 0.47 [0.19-1.17], P = .10), worsened mRS (21.2% vs 18.5%, OR = 1.08 [0.33-3.54], P = .9), and intraoperative blood loss (mean difference = 182.89 [-87.76, 453.55], P = .19).

CONCLUSION

The meta-analysis showed no significant difference in AVM obliteration, mortality, complications, worse mRS, and intraoperative blood loss between MS and E + MS groups. For AVMs where MS alone has acceptable results, it is reasonable to bypass unnecessary preoperative embolization given higher postoperative complication risk.

Multimodality treatment for brain arteriovenous malformation in Mainland China: design, rationale, and baseline patient characteristics of a nationwide multicenter prospective registry

BACKGROUND

Brain arteriovenous malformation (AVM) is an important cause of hemorrhagic stroke in young adults, which can lead to severe neurological impairment. The registry of Multimodality treatment for brain ArTeriovenous malformation in mainland CHina (MATCH) is a national prospective registry to identify the natural history of AVMs in Asian population; to investigate traditional and emerging hemorrhagic predictors; and to explore the superiority of the multidisciplinary assessment in improving the long-term outcomes.  METHODS: Consecutive AVM patients will be enrolled from 52 participating hospitals in mainland China. Baseline demographic, clinical and imaging data will be collected prospectively. Conservation, microsurgery, embolization, stereotactic radiosurgery (SRS), and multimodal strategies are all included in this study. Patients will be divided into experimental and control group according to whether the treatment protocols are formulated by multidisciplinary team. Neurofunctional status, subsequent hemorrhage, seizure, and novel neurofunctional deficit will be queried at 3 months, annually (1 and 2 years), 3 years, and 10 years follow-up.

RESULTS

Between August 2011 and April 2021, 3241 AVMs were enrolled in 11 participating sites. Among them, 59.0% were male with an average age of 28.4 ± 14.6 years, 61.2% had rupture history and 2268 hemorrhagic events occurred before admission. The median Spetzler-Martin grade and Lawton-Young grade was 3 and 5, respectively. Microsurgery is the dominant strategy (35.7%), with a similar proportion of embolization, SRS, and a combination of both (12.7%; 14.8%; 11.8%; respectively). Among them, 15.43% underwent multidisciplinary assessment and received standardized treatment. At the most recent follow-up, 7.8% were lost and the median follow-up duration was 5.6 years.

CONCLUSIONS

The MATCH study is a large-sample nationwide prospective registry to investigate multimodality management strategy for AVMs. Data from this registry may also provide the opportunity for individualized risk assessment and the development of optimal individual management strategies.

TRIAL REGISTRATION

ClinicalTrials.gov Registry ( NCT04572568 ).

Critical Appraisal of Randomized Controlled Trials on Unruptured Brain Arteriovenous Malformations

OBJECTIVE

Brain arteriovenous malformations management remains controversial despite the numerous, available treatment options. Randomized controlled trials (RCTs) theoretically provide the strongest evidence for the assessment of any therapeutic intervention. However, poorly designed RCTs may be associated with biases, inaccuracies, and misleading conclusions. The purpose of our study is to assess reporting transparency and methodological quality of the existing RCTs.

METHODS

A search was performed in the PubMed, Scopus, Embase, clinicaltrials.gov, and Cochrane databases. The search was limited to English literature. We included all published RCTs reporting on the management of unruptured brain arteriovenous malformations. The eligible studies were evaluated by 5 blinded raters with the CONsolidated Standards of Reporting Trials 2010 statement and the risk-of-bias 2 tool. The inter-rater agreement was assessed with the Fleiss' Kappa.

RESULTS

A randomized trial of unruptured brain arteriovenous malformations (ARUBA) and treatment of brain arteriovenous malformations (TOBAS) trials were evaluated. ARUBA achieved high CONsolidated standards of reporting trials compliance, while TOBAS showed a moderate one. In ARUBA the introduction, discussion, and other information sections reached the highest compliance rate (80%-86%). The lowest rates were recorded in the results and the methods (62% and 73%, respectively). The inter-rater agreement was moderate to substantial (54.1% to 78.4%). All the examined studies demonstrated a high risk of bias, mainly related to ill-defined intended interventions, missing outcome data, and selection of the reported results.

CONCLUSIONS

Our study confirmed the high risk of bias mainly attributed to several protocol violations, deviations, minimal external validity and selection, attrition, and allocation biases of the ARUBA trial. Analysis of the TOBAS trial revealed a moderate overall reporting clarity and a high risk of bias.

Assessment of gamma knife radiosurgery for unruptured cerebral arterioveneus malformations based on multi-parameter radiomics of MRI

OBJECTIVE

The treatment of Gamma knife radiosurgery (GKS) for unruptured Arteriovenous Malformations (AVM) remains controversial. A safe, effective and non-invasive method to predict outcome seems attractive for GKS. The purpose of this study was to develop and validate a MRI based multi-parameter radiomics model predicting the outcome of GKS for unruptured AVM.

METHODS

Eighty-eight unruptured AVM patients who initial underwent GKS between January 2011 and December 2016 in our hospital were included in this retrospective study. Patients were divided into two groups named as favourable and unfavourable outcome, according to the clinical outcome. Favourable outcome was defined as obliteration without post-SRS hemorrhage or permanent radiation-induced changes (RIC). Multivariate logistic regression analysis was used to select appropriate clinical features and construct a clinical predicting model. In terms of radiomic model, manually segmentation and radiomics extracted were performed on each AVM lesions. Finally, 1684 radiomics features were extracted and Recursive Feature Elimination (RFE) method combined with Random forest classifier were used for feature selection and model construction. The performance of the radiomics model was evaluated by the area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). In addition, the favourable group was further divided into early and late respond subgroup according to the time of obliteration evaluated by 2 years. The selected features were further compared according the respond time.

RESULTS

The median duration of neuroimaging follow-up was 65 months, 56 patients showed favourable outcome and 17 patients were observed obliteration within 2 years. The radiomics model constructed by 12 selected features achieved significant higher AUC of 0.88 (95% confidence interval 0.87-0.90) than traditional scoring system for predicting AVM outcome. Two selected radiomics features named "Dependence Variance" and "firstorder-Skewness" were found significant difference between the patients with early or late-respond.

CONCLUSIONS

The results suggest that the radiomics features could be successfully used for the pretreatment prediction of outcome for GKS in unruptured AVMs, which is helpful for decision-making process on unruptured AVM patients.

Interventional outcomes for patients eligible for entry into the ARUBA clinical trial: a systematic review and meta-analysis

OBJECTIVE

A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA) suggested that medical management afforded outcomes superior to those following intervention for unruptured arteriovenous malformations (AVMs), but its findings have been controversial. Subsequent studies of AVMs that would have met the eligibility requirements of ARUBA have supported intervention for the management of some cases. The present meta-analysis was conducted with the object of summarizing interventional outcomes for ARUBA-eligible patients reported in the literature.

METHODS

A systematic literature search (PubMed, Web of Science, Google Scholar) for AVM intervention studies that used inclusion criteria identical to those of ARUBA (age ≥ 18 years, no history of AVM hemorrhage, no prior intervention) was performed. The primary outcome was death or symptomatic stroke. Secondary outcomes included AVM obliteration, hemorrhage, death, and poor outcome (modified Rankin Scale score ≥ 2 at final follow-up). Bias assessment was performed with the Newcastle-Ottawa Scale, and the results were synthesized as pooled proportions.

RESULTS

Of the 343 articles identified through database searches, 13 studies met the inclusion criteria, yielding an overall study cohort of 1909 patients. The primary outcome occurred in 11.2% of patients (pooled = 11%, 95% CI 8%-13%). The rates of AVM obliteration, hemorrhage, poor outcome, and death were 72.7% (pooled = 78%, 95% CI 70%-85%), 8.4% (pooled = 8%, 95% CI 6%-11%), 9.9% (pooled = 10%, 95% CI 7%-13%), and 3.5% (pooled = 2%, 95% CI 1%-4%), respectively. Annualized primary outcome and hemorrhage risks were 1.85 (pooled = 2.05, 95% CI 1.31-2.94) and 1.34 (pooled = 1.41, 95% CI 0.83-2.13) per 100 patient-years, respectively.

CONCLUSIONS

Intervention for unruptured AVMs affords acceptable outcomes for appropriately selected patients. The risk of hemorrhage following intervention compared favorably to the natural history of unruptured AVMs. The included studies were retrospective and varied in treatment and AVM characteristics, thereby limiting the generalizability of their data. Future studies from prospective registries may clarify patient, nidus, and intervention selection criteria that will refine the challenging management of patients with unruptured AVMs.

Venous Rupture Following Transcatheter Arterial Embolization for Inferior Mesenteric Type II Arteriovenous Malformation

We treated a 64-year-old man who had an inferior mesenteric arteriovenous malformation with multiple shunts. As multiple varicosities in the draining vein became enlarged, two dilated shunts on the superior rectal and sigmoid colon arteries were coil embolized. Two days after embolization, a varicosity near the shunt (65 mm diameter) ruptured, causing intra-abdominal hemorrhage and surgical hemostasis. There were thrombi in the ruptured varicosity and its draining vein. The likely cause was a pressure increase in the incompletely thrombosed varicosity due to shunt blood flow from the remaining shunts after embolization.

Patient frailty association with cerebral arteriovenous malformation microsurgical outcomes and development of custom risk stratification score: an analysis of 16,721 nationwide admissions

OBJECTIVE

Patient frailty is associated with poorer perioperative outcomes for several neurosurgical procedures. However, comparative accuracy between different frailty metrics for cerebral arteriovenous malformation (AVM) outcomes is poorly understood and existing frailty metrics studied in the literature are constrained by poor specificity to neurosurgery. This aim of this paper was to compare the predictive ability of 3 frailty scores for AVM microsurgical admissions and generate a custom risk stratification score.

METHODS

All adult AVM microsurgical admissions in the National (Nationwide) Inpatient Sample (2002–2017) were identified. Three frailty measures were analyzed: 5-factor modified frailty index (mFI-5; range 0–5), 11-factor modified frailty index (mFI-11; range 0–11), and Charlson Comorbidity Index (CCI) (range 0–29). Receiver operating characteristic curves were used to compare accuracy between metrics. The analyzed endpoints included in-hospital mortality, routine discharge, complications, length of stay (LOS), and hospitalization costs. Survey-weighted multivariate regression assessed frailty-outcome associations, adjusting for 13 confounders, including patient demographics, hospital characteristics, rupture status, hydrocephalus, epilepsy, and treatment modality. Subsequently, k-fold cross-validation and Akaike information criterion–based model selection were used to generate a custom 5-variable risk stratification score called the AVM-5. This score was validated in the main study population and a pseudoprospective cohort (2018–2019).

RESULTS

The authors analyzed 16,271 total AVM microsurgical admissions nationwide, with 21.0% being ruptured. The mFI-5, mFI-11, and CCI were all predictive of lower rates of routine discharge disposition, increased perioperative complications, and longer LOS (all p < 0.001). Their AVM-5 risk stratification score was calculated from 5 variables: age, hydrocephalus, paralysis, diabetes, and hypertension. The AVM-5 was predictive of decreased rates of routine hospital discharge (OR 0.26, p < 0.001) and increased perioperative complications (OR 2.42, p < 0.001), postoperative LOS (+49%, p < 0.001), total LOS (+47%, p < 0.001), and hospitalization costs (+22%, p < 0.001). This score outperformed age, mFI-5, mFI-11, and CCI for both ruptured and unruptured AVMs (area under the curve [AUC] 0.78, all p < 0.001). In a pseudoprospective cohort of 2005 admissions from 2018 to 2019, the AVM-5 remained significantly associated with all outcomes except for mortality and exhibited higher accuracy than all 3 earlier scores (AUC 0.79, all p < 0.001).

CONCLUSIONS

Patient frailty is predictive of poorer disposition and elevated complications, LOS, and costs for AVM microsurgical admissions. The authors’ custom AVM-5 risk score outperformed age, mFI-5, mFI-11, and CCI while using threefold less variables than the CCI. This score may complement existing AVM grading scales for optimization of surgical candidates and identification of patients at risk of postoperative medical and surgical morbidity.

Fatal ruptured occult arteriovenous malformation in a young adult: An autopsy case report

Background:

Brain arteriovenous malformations (AVMs) are congenital developmental disorders with unclear causative factors and pathogenic mechanisms. Various epigenetic factors may influence the development and rupture of AVMs. Ruptured AVMs may lead to poor outcomes. Therefore, the risk factors of AVM rupture and treatment strategies for unruptured AVMs should be explored. Herein, we report a case of a fatal ruptured AVM diagnosed by radiological and autopsy findings and review the literature regarding AVM treatment.

Case Description:

A 46-year-old man was brought to the hospital with sudden loss of consciousness while sitting on the edge of the bathtub. On examination, he was unconscious with poor breathing efforts. He was intubated and a brain CT scan was performed, which showed an intracerebral hemorrhage (ICH) adjacent to the right trigone with massive intraventricular hemorrhage (IVH) and subarachnoid hemorrhage (SAH). Contrast-enhanced CT scan showed abnormal vessels adjacent to the hematoma. He was diagnosed with ICH associated with IVH and SAH caused by a ruptured abnormal vascular lesion. He underwent external ventricular drainage to control the intracranial pressure. He remained unconscious and died 16 h after hospital admission. Autopsy was performed to identify the cause of ICH. Pathological sections showed a mass of blood vessels, measuring 20 × 10 × 10 mm in size, within the hematoma with a single drainer connecting to the transverse sinus. These blood vessels had variable size, shape, and wall thickness on microscopy. Some vessels had abnormal thickened walls with discontinuous elastic fibers. Based on the radiological and autopsy findings, an ICH secondary to SpetzlerMartin Grade I AVM was confirmed.

Conclusion:

If the cause of ICH cannot be determined during a patient’s life, autopsy may be performed to determine the pathophysiology of occult vascular lesions, including AVMs. Patients with AVMs may have moderate or no symptoms before and after rupture. Because deep AVMs fed by posterior circulation have high risk of bleeding, surgical intervention should be considered for these patients to prevent a poor outcome. Low-grade and paraventricular AVMs in a young adult may be successfully treated with multimodal surgery.

Untangling the Modern Treatment Paradigm for Unruptured Brain Arteriovenous Malformations

Brain arteriovenous malformations (AVMs) often present treatment challenges. Patients with unruptured AVMs must consider not only whether they want to be treated, but what treatment modality they would prefer. Vascular neurosurgeons, neurointerventional surgeons, and stereotactic radiosurgeons must in turn guide their patients through the most appropriate treatment course considering the risk of AVM rupture, an individual AVM’s characteristics, and patient preferences. In this review we will look at how the clinical trial “A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA)” has influenced the approach to unruptured brain AVMs and the treatment modalities available to clinicians to deal with these formidable lesions.

Grading scale based on arcuate fasciculus segmentation to predict postoperative language outcomes of brain arteriovenous malformations

OBJECTIVE

The long-term postoperative language outcomes for brain arteriovenous malformations (bAVMs) have not been well characterised. With fibres scattered in the Broca's, Wernicke's and Geschwind's area, the arcuate fasciculus (AF) is considered as a crucial structure of language function. This study aimed to observe the language outcomes, determine the risk factors and construct a grading system for long-term postoperative language deficits (LDs) in patients with bAVMs involving the AF (AF-bAVMs).

METHODS

We retrospectively reviewed 135 patients with AF-bAVMs. Based on the course of the AF and our clinical experience, three boundary lines were drawn to divide the AF into segments I, II, III and IV in spatial order from the frontal lobe to the temporal lobe. Surgery-related LD evaluations were performed 1 week (short term) and at the last follow-up (long term) after surgery. Finally, based on multivariable logistic regression analysis, a grading system was constructed to predict long-term postoperative LD. The predictive accuracy was assessed using the area under the receiver operating characteristic curve (AUC).

RESULTS

Sixty-two (45.9%) patients experienced short-term postoperative LD. After a mean follow-up of 50.2±24.9 months, long-term LD was found in 14 (10.4%) patients. Nidus size (p=0.007), LD history (p=0.009) and segment II involvement (p=0.030) were independent risk factors for short-term LD. Furthermore, segment II involvement (p=0.002), anterior choroidal artery (AChA) feeding (p=0.001), patient age (p=0.023) and LD history (p=0.001) were independent risk factors for long-term LD. A grading system was developed by combining the risk factors for long-term LD; its predictive accuracy was 0.921.

CONCLUSIONS

The involvement of the trunk of the AF between Broca's area and the inferior parietal lobule, a nidus supplied by the AChA, older patient age and history of LD were associated with long-term postoperative LD. The grading system combining these factors demonstrated favourable predictive accuracy for long-term language outcomes.

Vessel Wall Magnetic Resonance Imaging in Cerebrovascular Diseases

Cerebrovascular diseases are a leading cause of disability and death worldwide. The definition of stroke etiology is mandatory to predict outcome and guide therapeutic decisions. The diagnosis of pathological processes involving intracranial arteries is especially challenging, and the visualization of intracranial arteries’ vessel walls is not possible with routine imaging techniques. Vessel wall magnetic resonance imaging (VW-MRI) uses high-resolution, multiparametric MRI sequences to directly visualize intracranial arteries walls and their pathological alterations, allowing a better characterization of their pathology. VW-MRI demonstrated a wide range of clinical applications in acute cerebrovascular disease. Above all, it can be of great utility in the differential diagnosis of atherosclerotic and non-atherosclerotic intracranial vasculopathies. Additionally, it can be useful in the risk stratification of intracranial atherosclerotic lesions and to assess the risk of rupture of intracranial aneurysms. Recent advances in MRI technology made it more available, but larger studies are still needed to maximize its use in daily clinical practice.

A systematic review and meta-analysis of surgeries performed for cerebral cavernous malformation-related epilepsy in pediatric patients

BACKGROUND

The clinical benefit of surgery for the treatment of cerebral cavernous malformation (CCM)-related epilepsy in pediatric patients is still controversial. Although surgical treatment of CCM-related epilepsy in children is widely recognized, the clinical benefits of controlling the seizure rate must be balanced against the risk of leading to perioperative morbidity.

METHODS

We conducted a comprehensive search to identify relevant studies via Ovid Medline, Web of Science and PubMed (January 1995-June 2020). The following search terms were used: "hemangioma, cavernous, central nervous system," "brain cavernous hemangioma," "cerebral cavernous hemangioma," "CCM," "epilepsy," and "seizures." The seizure control rate and the risk of postoperative adverse outcomes along with their 95% confidence intervals (CIs) were calculated.

RESULTS

A total of 216 patients across 10 studies were included in meta-analysis. The results showed that the control rate of epilepsy was 88% (95% CI: 76-95%). Four percent (95% CI: 2-10%) of the patients experienced temporary symptomatic adverse effects following surgical resection, and 3% (95% CI: 0-26%) of the patients developed permanent symptomatic adverse effects in the long-term follow-up after surgical excision of the CCMs. None of the patients died as a result of the CCMs or surgical treatment.

CONCLUSION

Surgery is an effective and safe treatment for CCM -related epilepsy in pediatric patients with a low risk of postoperative complications and death.

Microsurgical resection versus stereotactic radiosurgery for low-grade intracranial arteriovenous malformations: A 27-year institutional experience

The role of microsurgery and radiosurgery in the management of low-grade (Spetzler-Martin grade 1 and 2) arteriovenous malformations (AVMs) remains controversial. We aimed to compare outcomes of low-grade AVMs following microsurgery and radiosurgery using a database of AVM patients presenting between 1990 and 2017. Procedure-related complications, obliteration, and functional status at last follow-up were compared between groups. Hemorrhage-free survival was compared using Kaplan-Meier analysis with subgroup analyses by rupture status on presentation. The study involved 233 patients, of which 113 and 120 were treated with microsurgery and radiosurgery, respectively. The complication rates were statistically comparable between both treatment modalities. Mean follow-up time was 5.1 ± 5.2 years. In the complete cohort, there was no significant difference in hemorrhage-free survival between microsurgery and radiosurgery (log-rank p = 0.676, Breslow p = 0.493). When excluding procedure-related hemorrhage and partial resection, hemorrhage-free survival was significantly higher in the surgically treated cohort (log-rank = 0.094, Breslow p = 0.034). The obliteration rate was significantly higher in the surgical cohort (96% vs. 57%, p < 0.001), while functional status was similar. Microsurgery may offer superior hemorrhage-free survival in the early post-treatment period and demonstrates equivalent long-term hemorrhage control and functional outcome at 5 years compared to radiosurgery with nearly complete obliteration rates. Persistent neurologic deficits following microsurgery and symptomatic cerebral edema represent important treatment risks despite low SM grading. Appropriate patient selection even when dealing with low-grade AVMs is advised, as judicious patient selection and emphasis on technical success can minimize procedure-related hemorrhage and the incidence of subtotal resection.

Upfront and Repeated Gamma-Knife Radiosurgery for Small (≤5 mL) Unruptured Brain Arteriovenous Malformation: A Cohort of 249 Consecutive Patients

OBJECTIVE

According to A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA), conservative treatment seems to be superior to any intervention for unruptured brain arteriovenous malformations (AVMs). This study aims to evaluate safety and efficacy of upfront and repeated Gamma-Knife Radiosurgery (GKRS) in patients harboring small AVMs fulfilling the inclusion criteria of ARUBA.

METHODS

A retrospective study was conducted to evaluate outcomes of unruptured naive brain AVM with a volume ⩽ 5 mL eligible to ARUBA treated by GKRS with at least 3 years of follow-up.

RESULTS

From 1992 to 2014, 249 patients fulfilled the inclusion criteria of this study. The median age was 36 years (range: 18-78 years). The median treated volume of the nidus was 1.3 mL (range: 0.4-5 mL) and 63% of the AVM were in eloquent areas. Radiosurgery-based AVM score was 1-1.8 (76%), the Spetzler-Martin grade was II-III (73%), and the Virginia Radiosurgery AVM scale was ≤1 point (75%). The overall AVM obliteration rate was 77.1% after up to 3 GKRS sessions. The median dose at the margin was 24 Gy (15-25 Gy) and the median follow-up was 45 months (range: 36-205 months). Eight patients (3.2%) experienced hemorrhage after GKRS, corresponding to a post-GKRS hemorrhage annual rate of 1.03%. Permanent symptomatic radio-induced changes rate was 2% (4 increased seizures, 1 neurologic deficit).

CONCLUSIONS

The very low toxicity rate and the high occlusion rate suggest in favor of upfront and repeated GKRS for unruptured small AVMs (⩽5 mL).

Controlled arterial hypotension during resection of cerebral arteriovenous malformations

Background

Resection of cerebral arteriovenous malformations (AVM) is technically demanding because of size, eloquent location or diffuse nidus. Controlled arterial hypotension (CAH) could facilitate haemostasis. We performed a study to characterize the duration and degree of CAH and to investigate its association with blood loss and outcome.

Methods

We retrospectively analysed intraoperative arterial blood pressure of 56 patients that underwent AVM-resection performed by the same neurosurgeon between 2003 and 2012. Degree of CAH, AVM size, grading and neurological outcome were studied. Patients were divided into two groups, depending on whether CAH was performed (hypotension group) or not (control group).

Results

The hypotension group consisted of 28 patients, which presented with riskier to treat AVMs and a higher Spetzler-Martin grading. CAH was achieved by application of urapidil, increasing anaesthetic depth or a combination thereof. Systolic and mean arterial blood pressure were lowered to 82 ± 7 and 57 ± 7 mmHg, respectively, for a median duration of 58 min [25% percentile: 26 min.; 75% percentile: 107 min]. In the hypotension group, duration of surgery (4.4 ± 1.3 h) was significantly (p <  0.001) longer, and median blood loss (500 ml) was significantly (p = 0.002) higher than in the control group (3.3 ± 0.9 h and 200 ml, respectively). No case fatalities occurred. CAH was associated with a higher amount of postoperative neurological deficits.

Conclusions

Whether CAH caused neurological deficits or prevented worse outcomes could be clarified by a prospective randomised study, which is regarded as ethically problematic in the context of bleeding. CAH should only be used after strict indication and should be applied as mild and short as possible.

Analysis of potential time saving in brain arteriovenous malformation stereotactic radiosurgery planning using a new software platform

To evaluate the utility of integrating a 3D vessel tree co-registration software platform into the stereotactic radiosurgery (SRS) workflow and its time saving for brain arteriovenous malformation (bAVM) treatment in adults compared to the conventional stereotactic head frame workflow. Eight consecutive adult bAVM cases were selected and retrospectively reviewed. Total number of angiograms and SRS procedures were 8. The electronic medical records were analyzed by time stamps to determine the length of time for each component of the set-up, transport, and frame removal. Times were averaged and the start of sedation by anesthesia used as a surrogate for the start of the frame application process. Reductions in workflow times were then modeled assuming cerebral angiography as a separate procedure. There were 8 adult bAVM cases included. Six were female. All patients had a single treatment session. Average age was 51.5 years (Range: 36-71). All patients were treated under monitored anesthesia care. In 6 patients, the AVM was deeply located (basal ganglia, midbrain, brainstem); in 2 cases, the lesion was frontal. Spetzler-Martin grades were 4 (50%) Grade 2 and 4 (50%) Grade 3. The average prescription isodose volume (PIV) and 12 Gy volumes (V_12Gy) were 0.85 cc and 1.74 cc, respectively. The mean time from frame application to arrival in the angiography room was 111.5 minutes (range 40 to 171 min; median 107 min; SD 35.3 min); transport from angiography room to SRS was 47.5 minutes (range 15 to 107 min; median 36 min; SD 31.1 min), and frame removal after SRS was 20.5 minutes (range 10 to 47 min; median 16 min; SD 11.6 min). The average total additional time for the entire process of frame application, patient transportation, and frame removal was 132 minutes (range 87 to 181 min; median 127.5 min; SD 28.4 min). Therefore, assuming a non-frame based workflow and with angiography performed ahead of the actual radiosurgical treatment, the total time savings on the day of treatment was estimated at 132 minutes (range 87 to 181 min; median 127.5 min; SD 28.4 min). The ability to perform angiography, image fusion, and treatment planning for the actual day-of-delivery using 3-dimensional vessel tree co-registration could result in significant time savings over traditional workflow practices. Further experience with this system will evaluate its accuracy, reproducibility, and potential broader use in SRS workflow paradigms for the treatment of vascular pathologies. For bAVMs, the benefits of this time savings might allow for streamlined workflows on the day of SRS.

Intermediate-grade brain arteriovenous malformations and the boundary of operability using the supplemented Spetzler-Martin grading system

OBJECTIVE

Supplemented Spetzler-Martin grading (Supp-SM), which is the combination of Spetzler-Martin and Lawton-Young grades, was validated as being more accurate than stand-alone Spetzler-Martin grading, but an operability cutoff was not established. In this study, the authors surgically treated intermediate-grade AVMs to provide prognostic factors for neurological outcomes and to define AVMs at the boundary of operability.

METHODS

Surgically treated Supp-SM intermediate-grade (5, 6, and 7) AVMs were analyzed from 2011 to 2018 at two medical centers. Worsened neurological outcomes were defined as increased modified Rankin Scale (mRS) scores on postoperative examinations. A second analysis of 2000-2011 data for Supp-SM grade 6 and 7 AVMs was performed to determine the subtypes with improved or unchanged outcomes. Patients were separated into three groups based on nidus size (S1: < 3 cm, S2: 3-6 cm, S3: > 6 cm) and age (A1: < 20 years, A2: 20-40 years, A3: > 40 years), followed by any combination of the combined supplemented grade: low risk (S1A1, S1A2, S2A1), intermediate risk (S2A2, S1A3, S3A1, or high risk (S3A3, S3A2, S2A3).

RESULTS

Two hundred forty-six patients had intermediate Supp-SM grade AVMs. Of these patients, 102 had Supp-SM grade 5 (41.5%), 99 had Supp-SM grade 6 (40.2%), and 45 had Supp-SM grade 7 (18.3%). Significant differences in the proportions of patients with worse mRS scores at follow-up were found between the groups, with 24.5% (25/102) of patients in Supp-SM grade 5, 29.3% (29/99) in Supp-SM grade 6, and 57.8% (26/45) in Supp-SM grade 7 (p < 0.001). Patients with Supp-SM grade 7 AVMs had significantly increased odds of worse postoperative mRS scores (p < 0.001; OR 3.7, 95% CI 1.9-7.3). In the expanded cohort of 349 Supp-SM grade 6 AVM patients, a significantly higher proportion of older patients with larger Supp-SM grade 6 AVMs (grade 6+, 38.6%) had neurological deterioration than the others with Supp-SM grade 6 AVMs (22.9%, p = 0.02). Conversely, in an expanded cohort of 197 Supp-SM grade 7 AVM patients, a significantly lower proportion of younger patients with smaller Supp-SM grade 7 AVMs (grade 7-, 19%) had neurological deterioration than the others with Supp-SM grade 7 AVMs (44.9%, p = 0.01).

CONCLUSIONS

Patients with Supp-SM grade 7 AVMs are at increased risk of worse postoperative neurological outcomes, making Supp-SM grade 6 an appropriate operability cutoff. However, young patients with small niduses in the low-risk Supp-SM grade 7 group (grade 7-) have favorable postoperative outcomes. Outcomes in Supp-SM grade 7 patients did not improve with surgeon experience, indicating that the operability boundary is a hard limit reflecting the complexity of high-grade AVMs.

Coexistence of arteriovenous malformation and meningioma in a single patient: Systematic review and illustrative case

BACKGROUND

The coexistence of intracranial arteriovenous malformation (AVM) and meningioma in a single patient is seldom reported, so the clinical profile, optimal management, and outcomes of these patients are mostly unknown.

METHODS

We performed a systematic review of the SCOPUS and PubMed databases for case reports and case series on patients with both intracranial AVMs and meningiomas. Data on demographics, clinical characteristics, surgical management, and outcomes were collected.

RESULTS

A total of 18 cases were reported in the literature, including the present case. The mean age at presentation was 54 years (range of 15-70 years), with no gender predilection. Most of the meningiomas and AVMs were frontal in location, and more than half of the lesions were contiguous. The most common presenting symptoms were seizures (67%), headache (44%), and weakness (33%). Majority of the patients underwent single stage meningioma and AVM excision (44%), followed by staged meningioma excision then AVM excision (17%) and meningioma excision only (17%). In all, 94% (17/18) of the meningiomas were excised compared to 72% (13/18) of the AVMs. Outcomes were reported in 15 patients; 80% were favorable, but there were 2 deaths and 1 tumor recurrence after 5 years.

CONCLUSION

The coexistence of an intracranial AVM with a meningioma is recognized but rarely reported in the literature. Individualized treatment should be employed in managing patients with concurrent lesions, and outcomes are generally favorable due to the benign nature of both these entities.

Decision-Making for Patients With Cerebral Arteriovenous Malformations

Cerebral arteriovenous malformations (AVMs) are a complex and heterogeneous pathology which require an understanding of the natural history of these lesions, as well as the potential treatment options in order to manage them safely. While treatment is the agreed upon strategy for most ruptured AVMs, the management of unruptured AVMs continues to be debated. More recently, this debate has been fueled by the A Randomized Trial of Unruptured Arteriovenous Malformations (ARUBA) trial which attempts to define the natural history and treatment risk of AVMs. However, the trial has significant shortcomings which limit its broad applicability. In addition, the breadth, efficacy, and safety of potential treatment options continue to improve. This review focuses on defining the natural history of cerebral AVMs, an overview of the ARUBA trial, and the most current treatment paradigm for cerebral AVMs.

Spontaneous Regression Followed by Rupture of an Untreated Brain Arteriovenous Malformation

BACKGROUND

Brain arteriovenous malformations (AVMs) are dynamic lesions. Unlike the recruitment of additional vessels and the growth of the nidus over time, which are well reported in the literature, spontaneous regression is much less frequent. Only a handful of cases reporting recanalization of spontaneously regressed AVMs have been published. AVMs that undergo spontaneous regression typically share structural and historical features, including previous hemorrhage, a small nidus, superficial venous drainage, and a single draining vein. Structural features and hemodynamic changes may predispose brain AVMs to spontaneous regression, and angiogenic processes are hypothesized to contribute to recanalization and hemorrhage.

CASE DESCRIPTION

We present the case of a 37-year-old female who had been diagnosed 12 years ago with an unruptured Spetzler-Martin grade 3 AVM in the left medial occipital lobe after a history of progressively worsening migraines. The AVM was monitored for 1 year, but the patient was lost to follow-up until 11 years later, when the AVM nidus was found to be significantly smaller in size. One month later, the patient presented with acute intraparenchymal hemorrhage due to rupture of the AVM, which was then surgically resected.

CONCLUSIONS

Our case is the second reported case of rupture of a spontaneously regressed AVM and the first reported case of this outcome with no history of previous hemorrhage. Close monitoring of brain AVMs may be warranted for longer periods of time than previously recommended.

Interventional Neuroradiology: A Review

Interventional neuroradiology (INR) has evolved from a hybrid mixture of daring radiologists and iconoclastic neurosurgeons into a multidisciplinary specialty, which has become indispensable for cerebrovascular and neurological centers worldwide. This manuscript traces the origins of INR and describes its evolution to the present day. The focus will be on cerebrovascular disorders including aneurysms, stroke, brain arteriovenous malformations, dural arteriovenous fistulae, and atherosclerotic disease, both intra- and extracranial. Also discussed are cerebral vasospasm, venolymphatic malformations of the head and neck, tumor embolization, idiopathic intracranial hypertension, inferior petrosal venous sinus sampling for Cushing's disease, and spinal interventions. Pediatric INR has not been included and deserves a separate, dedicated review.

Radiotherapeutic management of brain tumours during the COVID-19 pandemic

Aim:

The coronavirus disease (COVID-19) pandemic is bound to put tremendous pressure on the existing healthcare system. This aim of this technical note is to help in triaging patients with brain tumours who are sent for radiotherapy during this pandemic and to provide safe and evidence-based care.

Materials and Methods:

Published data for this review were identified by systematically searching PubMed database from November 2007 onwards with the following Medical Subject Heading (Mesh) terms ‘Brain tumours’, ‘COVID-19’, ‘coronavirus’, ‘SARS-nCoV-2’, ‘Radiotherapy’, ‘Guidelines’ ‘hypofractionation’ using Boolean search algorithm. Articles in English language were reviewed.

Results:

We tried to apply the as low as reasonable achievable (ALARA) principle in triaging and management of patients for radiotherapy. We identified protocols which have hypofractionated regimens (reducing patient visits to hospital, time spent in treatment console) with similar outcomes when compared to conventional fractionated regimens and not overburdening the healthcare facility. We also identified the tumours for which we could safely avoid or delay the initiation of radiotherapy.

Conclusion:

Treatment decisions made during the COVID-19 pandemic rely on the safety first/do no harm principle and evidence-based prioritisation of cases for triage. This article is a tool to aid in triaging and prioritising brain tumour patient management. This is for consideration during the pandemic only and certainly not as a strategy for permanent practice change.