Oscillating intensity display of soft tissue lesions in MRI

A new postprocessing method for improving visualization of soft tissue lesions in MR images is described. Abnormal tissues are detected by a computerized tissue characterization algorithm which is based on measurements of intensity in a spatially matched pair of T1- and T2-weighted images. Simultaneous display of information from this pair of static images is achieved by using a temporal parameter (amplitude or frequency of intensity oscillation) to encode abnormal pixels. Specifically, a movie is created in which pixel intensities of abnormal tissues are made to oscillate so that the amplitude (or frequency) of oscillation is proportional to an abnormality index which depends on the difference between intensities of normal and abnormal tissues in the original image pair. The visual effect is that of a churning motion within the lesion, while surrounding normal tissues are displayed as stable structures. This technique increases the conspicuity of the lesion by exploiting the eye's great sensitivity to motion.