The purpose of this protocol is to evaluate new imaging technology for the early detection of coronary atherosclerosis in comparison to a previously established variation of the same method. The new method has a number of desirable features in comparison with the old, but its practical application would be enhanced if comparability could be established. This comparison is accomplished by simply conducting both new and established procedures in the same patients. No patient complications have occurred, though this should not be surprising given the simplicity of the experimental protocol, and the noninvasiveness of the underlying procedures. To date, we have collected data on 50 patients, and though this is far short of the number requested of the Institutional Review Board on statistical grounds, there appears to be good correlation between the two techniques. We plan to continue the protocol, and hope to publish the results of the comparison at a suitable time.