MRIW: parametric analysis software for contrast-enhanced dynamic MR imaging in cancer.

A software package called the Magnetic Resonance Imaging Workbench has been developed to characterize contrast agent uptake in vivo following T1-weighted magnetic resonance (MR) imaging with qualitative analysis of changes in signal intensity or quantitative analysis of changes in contrast agent concentration over time. Various descriptors may be calculated from the analysis of dynamic contrast agent-enhanced MR studies and visualized as false-color overlays, which allow the immediate display and interpretation of information taken from a series of images acquired over time. Qualitative descriptors include onset of enhancement, initial gradient, mean gradient, maximum enhancement, and washout. These parameters can be particularly useful in the investigation of multifocal or widespread disease. Quantitative descriptors include capillary permeability-surface area product, extracellular volume, and T1 and may be used to monitor changes in the disease state and to assess the efficacy of treatment. In addition, they allow comparison of data obtained from different patients, from independent MR studies, or from studies performed with different modalities. Analysis of contrast enhancement during MR imaging in terms of such qualitative or quantitative parameters is a promising new method of data analysis in radiology.