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

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

Clinical and Angioarchitectural Features of Ruptured Dural Arteriovenous Fistulas.

BACKGROUND: Hemorrhage is a feared complication of cranial dural arteriovenous fistulas (DAVFs). Traditional grading systems including the Cognard and Borden classifications assess for this risk. We sought to define the specific angioarchitecture of ruptured lesions. METHODS: A total of 41 cases between 2004 and 2019 with ruptured cranial DAVFs were retrospectively analyzed. Information reviewed from records and imaging included hematoma location, fistula anatomy and architecture, classification, venous pouches, common collecting veins, downstream stenosis, treatment, and outcomes. RESULTS: Mean age at presentation was 60 years, and 61% of patients were male. Hemorrhage was most commonly intraparenchymal, and the majority of fistulae were transverse-sigmoid, tentorial, or convexity. We noted that 71% of lesions had a multi-feeder-common-hole configuration. Venous aneurysms (present in 64% of patients) were in direct communication with the hematoma in 88%; 72% of cases were treated by endovascular means; 64% of patients were treated within 7 days. Five patients re-bled between diagnosis and treatment. A total of 83% of patients were functionally independent at last follow-up. CONCLUSIONS: Hemorrhage from cranial DAVFs is mostly intraparenchymal. Venous aneurysms are common and very often responsible for the bleed. Embolization yields high cure rates and should be performed early because of risk of re-hemorrhage. However, in spite of hemorrhage, DAVFs have a relatively favorable clinical outcome.

Application of PHASES and ELAPSS scores to ruptured cerebral aneurysms: how many would have been conservatively managed?

BACKGROUND: We calculated the PHASES and ELAPSS scores for a large cohort of ruptured intracranial aneurysms (RIA) in order to determine whether these RIA would have been pre-emptively treated or closely followed-up should they have been detected prior to rupture. METHODS: We retrospectively reviewed a consecutive series of RIA over a 20-year period. The primary outcome of this study was the PHASES score of each ruptured aneurysm included. Secondary outcomes were ELAPSS score and other risk factors for aneurysmal subarachnoid hemorrhage including aneurysm location, aneurysm size, aneurysm morphology, smoking and hypertension history, personal and family history of subarachnoid hemorrhage. Multiplicity of cerebral aneurysms was recorded. Descriptive statistics are reported. RESULTS: 700 consecutive ruptured aneurysms were included. Mean age at rupture was 56 (+/-13.5) years. Mean aneurysm size was 5.9 (+/-2.5) mm. Most common locations of ruptured aneurysms were the anterior cerebral/communicating artery (39%), posterior communicating artery (21%), middle cerebral artery (16%) and basilar terminus (7%). Mean PHASES score was 5.3 (+/-2.5) and 17% of the RIA had a PHASES score of 3 or less. Mean ELAPSS score was 13.89 (+/-7.05) and over half of the RIA included had a low risk of future growth. CONCLUSIONS: A reasonable percentage of ruptured aneurysms have a low calculated PHASES score and these aneurysms may have been managed conservatively should they have presented incidentally prior to rupture. Most ruptured aneurysms also had a low ELAPSS score and were at low risk of future growth. The use PHASES score and ELAPSS score alone when making treatment decisions could result in many aneurysms being treated conservatively or undergoing remote surveillance despite rupture potential.

Interval angioarchitectural evolution of brain arteriovenous malformations following rupture.

OBJECTIVE: The goal of this study was to describe changes in the angioarchitecture of brain arteriovenous malformations (bAVMs) between acute and delayed cerebral digital subtraction angiography (DSA) obtained after hemorrhage, and to examine bAVM characteristics predicting change. METHODS: This is a retrospective study of a prospective institutional bAVM database. The authors included all patients with ruptured bAVMs who had DSA in both acute and delayed phases, with no interval treatment of their bAVM, between January 2000 and April 2017. The authors evaluated the existence or absence of angioarchitectural changes. Demographic data, radiological characteristics of hemorrhages, and angioarchitectural features of the bAVMs of the two patients' groups were analyzed. Univariate and multivariate logistic analyses were performed to identify predictors of angioarchitectural change. RESULTS: A total of 42 patients were included in the series. Seventeen (40.5%) patients had angioarchitectural changes including bAVM only visible on the delayed DSA study (n = 8), spontaneous thrombosis of the AVM (n = 3), or alteration of the size or the opacification of the nidus (n = 6). The factors associated with angioarchitectural changes were a small nidus (3.8 ± 7.9 ml vs 6.1 ± 9.5 ml, p = 0.046), a superficial location (94.1% vs 5.9%, p = 0.016), and a single superficial draining vein (58.8% vs 24.0%, p = 0.029). CONCLUSIONS: Angioarchitectural changes can be seen in 40% of ruptured bAVMs between the acute- and delayed-phase DSA. A small nidus, a superficial location, and a single superficial draining vein were statistically associated with the occurrence of angioarchitectural changes. These changes included either enlargement or spontaneous occlusion of the bAVM, as well as subsequent diagnosis of a bAVM following an initial negative DSA study.

Endovascular treatment of intracranial vertebrobasilar artery dissecting aneurysms: Parent artery occlusion versus flow diverter.

PURPOSE: To compare the safety and efficacy of endovascular parent artery occlusion (PAO) and flow diverter (FD) treatment in treating vertebrobasilar dissecting aneurysms (VBDAs). METHODS: A review of a prospective aneurysm database at our institution was performed to identify all consecutive patients with intracranial VBDAs managed with endovascular treatment, which were either PAO or FD. Clinical and imaging findings were compared between the two groups. RESULTS: A total of 25 consecutive patients with 27 VBDAs were included. Seventeen VBDAs were treated by PAO, and 11 VBDAs were treated with FDs. Immediate total occlusion rate after initial treatment was higher in the PAO group than in the FD group (62.5% v.s. 9.1%, p = .018). Complete occlusion on follow-up at 18 months was more frequently observed in the PAO group (81.8%) compared to the FD group (55.6%), although the difference was not statistically significant (p = .433). Procedure related complication rate and mortality for the whole case series was 28% and 24% respectively, and were comparable in the two groups. Excellent outcome at discharge was achieved in 77.8% and 40% of patients treated with FD and PAO respectively, which was not statistically significant (p = .169). Excellent outcome at followed-up was comparable as well. CONCLUSIONS: PAO and FD treatment are both feasible options for treatment of VBDAs. PAO provide higher immediate complete occlusion rate compared to FD. Despite low initial complete occlusion rates, FD group presented a comparable long-term outcome and similar perioperative events rate compared to the PAO group.

Natural history and management of basilar trunk artery aneurysms.

BACKGROUND AND PURPOSE: Basilar trunk aneurysms (BTAs), defined as aneurysms distal to the basilar origin and proximal to the origin of the superior cerebellar artery, are rare and challenging to manage. We describe the natural history and management in a consecutive series of BTAs. METHODS: Between 2000 and 2013, 2522 patients with 3238 aneurysms were referred to our institution for aneurysm management. A retrospective review of this database was conducted to identify all patients with BTAs. RESULTS: In total, 52 patients had a BTA. Mean age was 56 (SD±18) years. Median clinical follow-up was 33 (interquartile range, 8-86) months, and imaging follow-up was 26 (interquartile range, 2-80.5) months. BTAs were classified into 4 causal subtypes: acute dissecting aneurysms, segmental fusiform ectasia, mural bleeding ectasia, and saccular aneurysms. Multiple aneurysms were more frequently noticed among the 13 saccular aneurysms when compared with overall population (P=0.021). There was preponderance of segmental ectasia or mural bleeding ectasia (P=0.045) in patients presenting with transit ischemic attack/stroke or mass effect. Six patients with segmental and 4 with mural bleeding ectasia demonstrated increasing size of their aneurysm, with 2 having subarachnoid hemorrhage caused by aneurysm rupture. None of the fusiform aneurysms that remained stable bled. CONCLUSIONS: BTAs natural histories may differ depending on subtype of aneurysm. Saccular aneurysms likely represent an underlying predisposition to aneurysm development because more than half of these cases were associated with multiple intracranial aneurysms. Intervention should be considered in segmental ectasia and chronic dissecting aneurysms, which demonstrate increase in size over time as there is an increased risk of subarachnoid hemorrhage.

Natural history and outcome after treatment of unruptured intradural fusiform aneurysms.

BACKGROUND AND PURPOSE: Management of unruptured fusiform intracranial aneurysms is controversial because of the paucity of natural history data. We studied their natural history and outcome after treatment. METHODS: We reviewed our neurovascular database from January 2000 to October 2013. Inclusion criteria were unruptured, intradural fusiform aneurysms with a diameter of <2.5 cm. Criteria were developed to define atherosclerotic aneurysms. For outcome assessment, we used the modified Ranking Scale and aneurysm measurements on serial imaging. Mann-Whittney (continuous) and Fisher exact (categorical) tests were used for risk factor analysis. RESULTS: For nonatherosclerotic aneurysms (96 patients; 193 person-years follow-up), 1 patient died (rupture) during follow-up (mortality, 0.51% per year) and 8 patients (10%) showed aneurysm progression (risk, 1.6% per year). Risk factors for progression were maximum diameter (>7 mm; odds ratio, 12; 95% confidence interval, 1.4-104) and symptomatic clinical presentation (odds ratio, 16; 95% confidence interval, 3.1-81.4). Of the 23 treated patients, 3 had died (mortality, 12.5%) and 3 had serious disability (modified Ranking Scale, ≥3; 12.5%). For the atherosclerotic aneurysms (25 patients; 97 person-years follow-up), 5 had died (mortality, 5.2% per year) and 13 of 20 (65%) had aneurysm progression (risk, 12% per year). When compared with patients with nonatherosclerotic aneurysms, case fatality (odds ratio, 19.2; 95% confidence interval, 2.1-172) and aneurysm progression (odds ratio, 17.8; 95% confidence interval, 5.3-56) were higher. CONCLUSIONS: Nonatherosclerotic fusiform intradural aneurysms have a low risk of adverse outcome within the first few years after diagnosis and remain stable unless symptomatic on presentation or >7 mm in maximum diameter. High risks of treatment should be balanced against this benign natural history. Atherosclerotic aneurysms have a worse natural history and may represent a different disease entity.