Advanced brain imaging procedures
infarct
INFARCT
On day 1 and 14, a routine brain MRI was acquired followed by an axial DTI scan. The MRI exam was performed on a GE Signa HDx 1.5 T scanner (GE Healthcare, USA). The DTI sequence parameters were as follows: spin-echo echo-planar imaging, repetition time = 6000 ms, echo time = 102.9 ms, field of view = 260 mm, b-value = 0 and 1000 s/mmThe maps of fractional anisotropy (FA), axial (AD), radial (RD) and mean (MD) diffusivity were derived from the raw DTI scans using the DTIMap plugin for Horos (v.1.6) [On day 14, a brain CTP scan was obtained using the Dankbaar’s approach [The CTP data were processed on a GE Advanced Workstation 4.7 (GE Healthcare, USA) using the CT Perfusion 4D program. As a result, a series of the permeability–surface area product (PS) maps were obtained.The most representative slice was chosen for analysis in each set of images. On that slice, the infarcted area was outlined and mirrored to the contralateral hemisphere. The values of FA, AD, RD, MD, and PS were assessed within each region of interest (Fig. Advanced brain imaging. The most representative slice was selected from a set of diffusion-tensor imaging and CT perfusion scans. The region of interest is outlined on the affected side (*) and is mirrored to the contralateral hemisphere. To cope with the heterogeneity of the ischemic lesions due to different locations, we calculated absolute values of the laterality index for each parameter using the formula [The infarct volume was calculated on DWI (on day 1) and CT (on day 14) scans according to the ABC/2 method [