MEASUREMENT OF WATER MOTION (APPARENT DIFFUSION) IN BIOLOGICAL-SYSTEMS

This work describes the basics of diffusion measurement in biological systems. The first portion is dedicated to providing an understandable , classical-mechanical description of the Stejskal-Tanner pulse sequen ce to give the reader an intuitive understanding of the measurement. T his is followed by a description of the various aspects of water motio n in biological systems that should be taken into account when making and interpreting apparent diffusion coefficient (ADC) measurements. Th ese include free diffusion, restricted diffusion, diffusion anisotropy , population weighting, and the difference between diffusion-weighted imaging (DWI) and ADC maps. (C) 1997 John Wiley & Sons, Inc.