Abstract WMP62: Assessment Of Cerebral Hemodynamic Patterns In Cervical Arterial Dissection Using Quantitative Magnetic Resonance Angiography

Abstract

Background: Cervical arterial dissection accounts for 2-3% of all ischemic strokes. The pathophysiologic mechanism of the ensuing neurological sequelae is largely attributed to embolic phenomenon. The degree to which the dissection may limit cerebral blood flow and its relationship to symptoms is currently not well characterized. This study is the first to evaluate and quantify blood flow using quantitative magnetic resonance angiography (QMRA) in this patient population. Methods: A retrospective chart review was completed in patients at this institution with cervical arterial dissection between August 31, 2009, to September 1, 2019. Inclusion criteria were adults (≥18 years) with diagnosis of dissection of the common carotid artery, internal carotid artery, or vertebral artery, who received QMRA neuroimaging. The cases were reviewed for clinical presentation, diagnosis, management strategy, and radiologic imaging finding. Flow index was calculated using the ipsilateral vessel flow divided by the contralateral flow. Statistical analyses were completed using SPSS software (Version 27, IBM Corporation, Armonk, NY). Results: A total of 41 patients were included in this study, 53.7% male and 46.3% female, with mean age 46.0 +/- 11.9 years. Twenty-one patients (51.2%) had ICA dissections while 19 patients (46.3%) had VA dissections, and 1 patient had both ICA and VA vessels affected. Patients with ischemia on MRI demonstrated lower flow in the ipsilateral vessel when compared to those patients without ischemia on MRI at diagnosis and follow-up (p=0.003). Although flow improved over time, patients continued to remain stratified: patients with the lowest index on presentation tended to continue to have low flow in the ipsilateral vessel (p=0.000). Using the flow index in ROC analysis to predict ischemia on MRI yielded an area under the curve of 0.833 (p=0.002); ROC analysis of the percent of total flow for ischemia on MRI found an AUC of 0.895 (p=0.000). Conclusion: This study represents the first to assess vessel flow in patients with cervical arterial dissection using QMRA. Patients with lower flow as a result of dissection appear to be at higher risk of ischemia on presentation, emphasizing the role of hemodynamics in the underlying pathophysiology.