Systems, devices, and methods for non-invasive image-based plaque analysis and risk determination

A computer-implemented method of determining a probabilistic threshold of ischemia for a coronary artery based at least in part on a stenosis percentage generated from image-based analysis, the method comprising:

• accessing, by a computer system, a first medical image of a subject, the first medical image comprising a region of a coronary artery of the subject;
• analyzing, by the computer system, the first medical image to identify the region of the coronary artery using image segmentation;
• identifying, by the computer system, one or more regions of plaque within the region of the coronary artery, wherein the one or more regions of plaque are identified based at least in part on density of one or more pixels in the first medical image corresponding to the one or more regions of plaque;
• determining, by the computer system, a percentage of one or more stenoses present in the region of the coronary artery arising from the one or more regions of plaque, wherein the percentage of one or more stenoses is determined based at least in part on interpolating a lumen volume or diameter of the region of the coronary artery without the one or more regions of plaque;
• and
• determining, by the computer system, a probabilistic threshold of ischemia for the region of the coronary artery based at least in part on the percentage of the one or more stenoses present in the region of the coronary artery and a plurality of reference values of percentages of stenoses with known presence or absence of ischemia derived from a plurality of other subjects, wherein the probabilistic threshold of ischemia comprises a statistical likelihood of the region of the coronary artery being ischemic, wherein the probabilistic threshold of ischemia for the region of the coronary artery being higher than a predetermined threshold is indicative of a need for further assessment of ischemia for the subject,
• wherein the computer system comprises a computer processor and an electronic storage medium.