Wisconsin Alumni Research Foundation

Mark M Bahn

James A Sorenson

Yi-Hsuan Kao

An MRI system acquires a series of images over a course of time using an echo planar imaging pulse sequence. A susceptibility contrast agent is injected into the subject during the scan to momentarily reduce NMR signal strength from voxels with blood flow. A nonlinear regression parameter estimation process is employed to calculate blood volume at each voxel directly from the acquired NMR data.

Magnetic resonance imaging of blood volume

A dual echo magnetic resonance imaging system produces two registered images of a patient in which the images have different contrast relationships between different tissue types. A two dimensional feature space histogram of the two images is produced and a separate centroid is located in the feature space histogram for each one of a pair of tissue types. A Cartesian coordinate system is defined in the feature space so that one axis of the system passes through the two centroids. Vector decomposition is employed to project each image element data point in the feature space onto a point on the one axis. The fractional quantity of each tissue type present in the image element is determined based upon the Euclidean distances from that axis point to the respective centroids. The fractional quantity is calculated for each element in the original images to form a pair of tissue images. The elements of a tissue image are processed to measure the amount of that tissue type in the imaged portion of the patient.

Growing community of inventors

Madison, WI, United States of America

Mark M Bahn