Assessing the rate, natural history, and treatment trends of intracranial aneurysms in patients with intracranial dural arteriovenous fistulas: a Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) investigation

Abstract

OBJECTIVE There is a reported elevated risk of cerebral aneurysms in patients with intracranial dural arteriovenous fistulas (dAVFs). However, the natural history, rate of spontaneous regression, and ideal treatment regimen are not well characterized. In this study, the authors aimed to describe the characteristics of patients with dAVFs and intracranial aneurysms and propose a classification system. METHODS The Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database from 12 centers was retrospectively reviewed. Analysis was performed to compare dAVF patients with (dAVF+ cohort) and without (dAVF-only cohort) concomitant aneurysm. Aneurysms were categorized based on location as a dAVF flow-related aneurysm (FRA) or a dAVF non–flow-related aneurysm (NFRA), with further classification as extra- or intradural. Patients with traumatic pseudoaneurysms or aneurysms with associated arteriovenous malformations were excluded from the analysis. Patient demographics, dAVF anatomical information, aneurysm information, and follow-up data were collected. RESULTS Of the 1077 patients, 1043 were eligible for inclusion, comprising 978 (93.8%) and 65 (6.2%) in the dAVF-only and dAVF+ cohorts, respectively. There were 96 aneurysms in the dAVF+ cohort; 10 patients (1%) harbored 12 FRAs, and 55 patients (5.3%) harbored 84 NFRAs. Dural AVF+ patients had higher rates of smoking (59.3% vs 35.2%, p < 0.001) and illicit drug use (5.8% vs 1.5%, p = 0.02). Sixteen dAVF+ patients (24.6%) presented with aneurysm rupture, which represented 16.7% of the total aneurysms. One patient (1.5%) had aneurysm rupture during follow-up. Patients with dAVF+ were more likely to have a dAVF located in nonconventional locations, less likely to have arterial supply to the dAVF from external carotid artery branches, and more likely to have supply from pial branches. Rates of cortical venous drainage and Borden type distributions were comparable between cohorts. A minority (12.5%) of aneurysms were FRAs. The majority of the aneurysms underwent treatment via either endovascular (36.5%) or microsurgical (15.6%) technique. A small proportion of aneurysms managed conservatively either with or without dAVF treatment spontaneously regressed (6.2%). CONCLUSIONS Patients with dAVF have a similar risk of harboring a concomitant intracranial aneurysm unrelated to the dAVF (5.3%) compared with the general population (approximately 2%–5%) and a rare risk (0.9%) of harboring an FRA. Only 50% of FRAs are intradural. Dural AVF+ patients have differences in dAVF angioarchitecture. A subset of dAVF+ patients harbor FRAs that may regress after dAVF treatment.

Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR): rationale, design, and initial characterization of patient cohort

“…Detailed analyses examining the impact of treatment on the natural history and long-term outcome of patients presenting with benign versus aggressive symptoms and harboring differing dAVF subtypes and locations are the subject of a series of separate CONDOR studies. [44][45][46][47]…”

Angiographically Silent Ruptured Dural Arteriovenous Fistula Presenting As Subdural Hematoma

“…These malformations typically present with a combination of intracranial hemorrhage and subarachnoid hemorrhage. Some variation in clinical presentation is observed, depending on the presence or absence of a flow-related aneurysm [ 2 ]. Typically, these malformations are identifiable on a CT angiogram (CTA) and confirmed via catheter angiography.…”

Editorial. The use of big data for improving understanding of the natural history of neurosurgical disease

“…1 These studies have aided neurosurgeons in determining which treatment methodologies are best applied to certain patient populations with unruptured intracranial aneurysms, 2 vestibular schwannomas, 3 and dural arteriovenous fistulas. 4 There has been an exponential generation of healthcarerelated data in the past decade and, accordingly, increased usage of big data repositories in neurosurgical research. 5,6 These databases store vast quantities of de-identified patient information that are readily available for querying.…”