PROBING TUMOR MICROVASCULARITY BY MEASUREMENT, ANALYSIS AND DISPLAY OF CONTRAST AGENT UPTAKE KINETICS

This paper describes a measurement protocol for acquiring quantitative dynamic MRI data and novel analysis and display software (Magnetic Re sonance Imaging Workbench (MRIW)). Proton density-weighted and T1-weig hted two-dimensional gradient echo images are used to quantify tissue contrast agent concentration. The dynamic studies last approximately 7 minutes, with 10-second temporal resolution. Analyses of signal and c oncentration changes with time are performed, allowing capillary perme ability-surface area product, tissue leakage space, enhancement onset time, mean enhancement gradient and maximum enhancement level to be ma pped as false-color parametric overlays registered with anatomic image s. Quantification of permeability and leakage space provides a method for comparing physiology in patients between visits or for intersite c omparisons.