A computer system for the quantification of coronary artery stenoses-design of the human computer interface

A low-cost, clinically usable system has been developed for the objective assessment of the severity of coronary artery stenoses from single-view angiograms. The system is based on a desktop computer with incorporated frame grabber. Images are captured by means of a video camera. Both diameter and densitometric cross-sectional area measurements can be made on a selected artery segment. Particular attention has been paid to the design of an appropriate man-machine interface, suitable for clinical use. Software tools have been developed for this purpose. They facilitate an iterative approach to program development and also provide for the needs of both the experienced and inexperienced user. The stenosis analysis system has been tested by using phantoms constructed in Perspex. These are designed to simulate arteries of various diameters and also an asymmetric stenosis. Results show good agreement with measurements for videodensitometry; however, diameter measurements are hampered by the unreliability of the edge detection algorithm, particularly when severe stenoses are encountered