The accuracy of densimetric time parameters in the analysis of myocardial perfusion

Time-density curves from regions of interest in digitized X-ray images of a coronary-artery/myocardium model were used to derive parameters representing flow and volume. The complete time-density curve was predicted from the observed time-limited, sampled time-density curve by least-squares methods, allowing accurate computation of mean transit time and relative vascular volume. In agreement with indicator-dilution theory, the experiments reveal that not the maximum density but rather the integral of the time-density curve should be used to assess vascular volume