Intravascular ultrasound

A new technique has been developed to compute left ventricular (LV) time activity curves from gated blood pool (GBP) studies without the use of manual, semiautomated or fully automated edge detection algorithms. The method utilizes the correlation of entropy calculated from the counts of a fixed region of interest covering the left ventricle during a cardiac cycle to compute the LV volume curve for a new patient. The new LV volume curve is obtained through interpolation of those volume curves of a data base which are associated with the closest variations in normalized entropy to the new one. The computed LV time activity curves agree with those obtained from manual or fully automated outlines of the left ventricle within 9 percent for the selected set of 67 patients demonstrating the potential of the method. The accuracy of calculated LV volume curves can be improved theoretically to any degree by increasing the number of cases in the data base of known statistical feature vectors associated with the LV images and LV volume curves. The new method for computation of LV curves is very efficient and robust when compared to traditional techniques.