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 Resonance Imaging Workbench (MRIW)). Proton density-weighted and T1-weighted 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 concentration changes with time are performed, allowing capillary permeability-surface area product, tissue leakage space, enhancement onset time, mean enhancement gradient and maximum enhancement level to be mapped as false-color parametric overlays registered with anatomic images. Quantification of permeability and leakage space provides a method for comparing physiology in patients between visits or for intersite comparisons.