Methods Patients

Gradient echo (GRE) MRI has been demonstrated to be more sensitive than computed tomography (CT) in detecting intracerebral hemorrhage, which is characterized as hypointensity on T2*-weighted GRE magnitude images.1,2 Hemoglobin in red blood cells becomes paramagnetic as it degenerates in hemorrhages.3 GRE is sensitive to local magnetic inhomogeneities. However, T2 * hypointensity is dependent on imaging parameters, including echo time (TE), field strength, and voxel size, making it difficult to estimate the hematoma volume (HV) reliably,4 a vital clinical predictor in managing hemorrhagic patients.5,6 Recently, a novel quantitative suscep-tibility mapping (QSM) technology for postprocessing GRE MRI data through deconvolution to reveal intrinsic tissue mag-netism and remove imaging parameter dependence7–9 has been applied successfully as a universal measurement of the bur-den of cerebral microbleeds, eliminating the T2 * dependence on imaging parameters.10 We hypothesize that QSM provides TE-independent measurement of HV in GRE MRI