Introduction: High-resolution magnetic resonance vessel wall imaging (MR-VWI) is increasingly being used to characterize intracranial vascular disease. Recent studies support a paradigm of avid vessel wall enhancement in ruptured (but not unruptured) intracranial aneurysms. Here we report our preliminary experience using MR-VWI in the evaluation of ruptured cranial dural arteriovenous fistulas (dAVFs).
Methods: A retrospective review of a prospective intracranial MR-VWI database identified a consecutive series of patients with ruptured cranial dAVFs. All patients underwent standard imaging including non-contrast CT, CT angiography, and digital subtraction angiography (DSA). High-risk angioarchitectural features, e.g., venous-side aneurysms and varices, were identified and a site-of-rupture determined, if possible, using traditional criteria. MR-VWI was used to evaluate high-risk angioarchictectural features for (1) robust enhancement and (2) contiguity to hemorrhagic blood products.
Results: Four of 7 patients with ruptured cranial dAVFs demonstrated at least one high-risk angioarchitectural feature on classical imaging thought to be the site-of-rupture. In all cases, this arterialized venous structure demonstrated robust vessel wall enhancement and was located immediately adjacent to hemorrhagic blood products on MR-VWI. In patients with multiple, high-risk angioarchitectural features, only the feature in contiguity with blood and thought to be the site-of-rupture demonstrated enhancement.
Conclusions: MR-VWI may be useful in the evaluation of ruptured cranial dAVFs. In particular, it may aid in site-of-rupture identification. These findings support an emerging paradigm that spontaneously ruptured, macrovascular structures, e.g., intracranial aneurysms, demonstrate avid vessel wall enhancement.
Patient Care: This study suggests that MR-VWI may inform site-of-rupture identification in patients with ruptured cranial dAVFs. This information may be particularly useful when complete obliteration of the fistula is not achieved.
Learning Objectives: To understand the possible utility of MR-VWI in the evaluation of ruptured cranial dAVFs.
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2. Matouk CC, Mandell DM, Gunel M, et al. Vessel wall magnetic resonance imaging identifies the site of rupture in patients with multiple intracranial aneurysms: proof of principle. Neurosurgery 2013;72:492-496; discussion 496
3. Matouk CC, Cord BJ, Yeung J, et al. High-resolution Vessel Wall Magnetic Resonance Imaging in Intracranial Aneurysms and Brain Arteriovenous Malformations. Top Magn Reson Imaging 2016;25:49-55