In vivo validation of an experimental adaptive quantitative coronary angiography algorithm to circumvent overestimation of small luminal diameters

David Keane, Ed Gronenschild, Cornelis Slager, Yukio Ozaki, Jürgen Haase, Patrick W. Serruys
1995 Catheterization and Cardiovascular Diagnosis  
The reliability of quantitative coronary angiography (QCA) measurements is of fundamental importance for the study and practice of lnterventional cardiology. In vivo validation results have consistently reported a tendency for QCA systems to overestimate small luminal diameters. Such a systematic error may result In the underestimation of luminal gain during intracoronary procedures and in the underestlmation of progression of coronary artery disease during longltudlnal studies. We report the
more » ... vivo valldatlon results of an experimental adaptive edge-detection algorithm that was developed to reduce overestimation of small luminal dlameters by incorporating a dynamic function of variable kernel size of the derivative operator and variable weighting of the first and second derivatives of the brightness profile. The results of the experimental algorithm were compared to those of the conventional parent edge detection algorithm with fixed parameters. Dynamlc adjustment of the edgedetection algorithm parameters was found to improve measurements of small (<0.8-mm) luminal dlameters as evidenced by an intercept of +.07 mm for the algorithm with variable welghtlng compared to +0.21 mm for the parent algorithm with flxed weighting. A slope of <1 was found for both the parent and experimental algorithms with subsequent underestimation of large luminal dlameters. Systematic errors In a QCA system can be identified and corrected by the execution of objective in vivo validation studies and the consequent refinement of edge-detection algorithms. The overestimation of small luminal diameters may be overcome by the Incorporation of a dynamic edgedetection algorithm. Further refinements in edge-detection algorithms will be required to address the Issue of underestlmation of large luminal diameters before the absolute values derived from QCA measurements can be considered accurate over the full range of clinically encountered luminal diameters. D 1995 Wiley-Lir, Inc.
doi:10.1002/ccd.1810360106 pmid:7489588 fatcat:wmwsbm7mnnhtpfhshpddbj3uue