Comparison of diffusion MRI methods in the study of structural reorganization of the brain in the early post-stroke period

Abstract

Current research in the field of neuroimaging is focused on the possibilities of using data from various diffusion MR models: diffusion tensor visualization (DTI), diffusion-curtosis visualization (DKI), diffusion-spectral visualization (DSI), generalized q-sample visualization (GQI), Q-ball visualization (QBI) in the assessment reorganization of the brain. The purpose of this study is to compare the results of dynamic observation of post–stroke brain reorganization by diffusion MR models (DTI, DKI). Material and methods. Dynamic MR examination of the brain of 129 patients was performed on a Ingenia 3.0 T (Philips, Netherlands) on 1–3 days, 7–10 days, 3–4 months after the manifestation of stroke according to a routine protocol (DWI-EPI, FLAIR-SPIR, T2-WI, T1W-TFE) with DTI method. The stroke was verified and DTI, GQI, and DKI maps were built. Results and discussion It was showed that the fractional anisotropy (FA) of DTI significantly changed from 1–3 days to 7–10 days in the stroke area; the mean, axial and radial diffusions increased in the affected area over the three studies. For DKI model – the curtosis FA significantly changed in the lesion area by 3–4 months; the mean curtosis decreased by the second observation in the stroke area, axial curtosis decreased in the same area throughout all studies; radial kurtosis significantly increased in the affected area throughout the study. The results confirm the world data and also indicate that diffusion metrics can interpret the neuroplasticity of the brain in various diseases, however, this requires further study. The applied diffusion models indicated the reorganization of the ischemic area and the intact contralateral area. The use of diffusion models for the dynamic assessment is a promising direction in the study of the neuroplasticity mechanisms.