摘要: The principles of contrast mechanisms and fast pulse sequences underlying neurological neuroradiological application MRI are introduced in this part a two-part review. In particular, the relaxation time constants T(1), T(2), T(2) (*) introduced, along with harnessing their contrast, spin-echo, spin echo (FSE), inversion recovery (IR), gradient recalled (GRE), planar imaging (EPI). use gadolinium (Gd)-based is discussed both T(1)- (*)-weighted sequences. Tradeoffs between speed image quality discussed, particularly context long train (FSE EPI). influence parallel strategies also discussed. sensitivity as source artifact well mechanism (perfusion agents, susceptibility weighted [SWI], blood oxygenation level dependent [BOLD] imaging). Finally, diffusion concept anisotropy. From these principles, other review draws upon to design disease indication-specific protocols for state-of-the-art clinical use.