Lower Blood Pressure Is Not Associated With Decreased Arterial Spin Labeling Estimates of Perfusion in Intracerebral Hemorrhage

Abstract

Background Subacute ischemic lesions in intracerebral hemorrhage ( ICH ) have been hypothesized to result from hypoperfusion. Although studies of cerebral blood flow ( CBF ) indicate modest hypoperfusion in ICH , these investigations have been limited to early time points. Arterial spin labeling ( ASL ), a magnetic resonance imaging technique, can be used to measure CBF without a contrast agent. We assessed CBF in patients with ICH using ASL and tested the hypothesis that CBF is related to systolic blood pressure ( SBP ). Methods and Results In this cross‐sectional study, patients with ICH were assessed with ASL at 48 hours, 7 days, and/or 30 days after onset. Relative CBF ( rCBF ; ratio of ipsilateral/contralateral perfusion) was measured in the perihematomal regions, hemispheres, border zones, and the perilesional area in patients with diffusion‐weighted imaging hyperintensities. Twenty‐patients (65% men; mean± SD age, 68.5±12.7 years) underwent imaging with ASL at 48 hours (N=12), day 7 (N=6), and day 30 (N=11). Median (interquartile range) hematoma volume was 13.1 (6.3–19.3) mL. Mean± SD baseline SBP was 185.4±25.5 mm Hg. Mean perihematomal rCBF was 0.9±0.2 at 48 hours at all time points. Baseline SBP and other SBP measurements were not associated with a decrease in rCBF in any of the regions of interest ( P ≥0.111). r CBF did not differ among time points in any of the regions of interest ( P ≥0.097). Mean perilesional rCBF was 1.04±0.65 and was unrelated to baseline SBP ( P =0.105). Conclusions ASL can be used to measure rCBF in patients with acute and subacute ICH . Perihematomal CBF was not associated with SBP changes at any time point. Clinical Trial Registration URL: http://www.clinicaltrials.gov . Unique identifier: NCT00963976.