Abstract WP158: Cortical Superficial Siderosis is Associated With Ischemia After Intracerebral Hemorrhage

Abstract

Background: Ischemia on diffusion weighted imaging (DWI) after intracerebral hemorrhage (ICH) increases the risk of future ischemic stroke. Radiographic markers of small vessel disease, including cerebral microbleeds (CMB), are associated with DWI lesions. Though cortical superficial siderosis (cSS) is also a hemorrhagic small vessel disease subtype, it is unclear if cSS similarly relates to DWI lesions. We hypothesized that cSS would represent a more severe phenotype of small vessel disease and would associate with DWI lesions after ICH independent to other small vessel disease markers. Methods: Using the Intracerebral Hemorrhage Outcomes Project (ICHOP), we included all cases of spontaneous ICH who underwent DWI and susceptibility imaging/gradient echo. DWI hyperintensities were identified if >10mm from the hematoma with decreased ADC signal. cSS were identified as subarachnoid hemosiderin deposition without acute subarachnoid hemorrhage. The relationship of cSS with DWI lesion presence as the outcome was assessed with logistic regression adjusted for ICH score, blood pressure change within 24 hours, and small vessel disease markers (CMB and white matter hyperintensity). Sensitivity analyses were performed to adjust for demographics and ICH location. A secondary analysis using linear regression assessed the association with the number of DWI lesions adjusted for similar covariates. Results: Of 198 patients analyzed, DWI lesions were observed in 31.3% and cSS in 10.6%. The presence of cSS was associated with DWI lesions (adjusted OR 3.72, CI: 1.29-10.72), independent of other small vessel disease markers. Separate sensitivity analyses adjusting for sex, race, and ICH location did not change the association of cSS with DWI lesions. In secondary analyses, cSS was not associated with greater number of DWI lesions counts (b 0.213, CI -0.53-0.63). Discussion: cSS is associated with the presence of DWI lesions, independent to other small vessel disease markers. cSS may represent a severe phenotype of small vessel disease with a risk of ICH recurrence and ischemia. Further work is required to investigate underlying mechanisms and optimal strategies to mitigate competing risks of future hemorrhage and ischemic events in these patients.