Abstract TP341: Yield of Interval Magnetic Resonance Imaging in Determining Cryptogenic Etiologies of Spontaneous Intracerebral Hemorrhage

Abstract

Introduction: Spontaneous intracerebral hemorrhage (ICH) most commonly arises due to primary etiologies such as hypertensive or cerebral amyloid angiopathy (CAA), but may also occur due to underlying secondary causes such as vascular malformations or intracranial neoplasms. However, focal mass effect may potentially obscure underlying lesions on neuroimaging performed during the acute phase of ICH, and follow-up imaging is often recommended. We sought to determine the yield of interval magnetic resonance imaging (MRI) in identifying cryptogenic ICH etiologies. Methods: We performed a single-center descriptive cohort study of consecutive patients enrolled in an institutional ICH registry over 12 months. ICH features including etiology and acute neuroimaging were prospectively adjudicated, while planned interval follow-up imaging was retrospectively reviewed. We determined the frequency of newly-discovered findings on interval MRI, and classified new findings according to whether or not they contributed meaningfully to patient management. Results: There were 241 ICH patients in our cohort who survived to discharge and did not have MRI-incompatible devices; 44 had planned follow-up imaging and 33 ultimately completed a follow-up MRI. Mean interval between initial and follow-up MRI was 61 (±34) days. New findings were identified in 33% of follow-up cases (11/33), with changes in patient management occurring in 12% (4/33). Age (59.4 vs. 61.5, p=0.74), sex (45% vs. 45% male, p>0.99), and secondary ICH score (median 3 [IQR 2-3] vs. 3 [1-4], p=0.87) were not significantly different between patients who had new findings and those who did not. New findings included cavernoma (n=4; 1 underwent resection), CAA-related changes (n=3), intracranial malignancy (n=2; 1 transitioned to hospice care, 1 led to cancer workup), new embolic stroke (n=1, underwent extended cardiac monitoring), and demyelination (n=1). Conclusions: Interval MRI aided in diagnosing ICH etiology in one-third of patients who received one, though few cases led to direct actionable changes in patient management.