Computer recognition of radiopaque myocardial markers

Radiopaque markers implanted in the heart have been used both clinically and experimentally to examine cardiac function. From the position of the markers, both regional and global function can be determined. A major problem with using radiopaque markers is the excessive time required for data analysis. Each marker in every cine frame must be identified and digitized by the investigator. To circumvent this problem, a computer system was developed to automatically identify the markers. The cine film is projected onto a TV camera from which the video signal is digitized and transferred into a computer. The investigator identifies the markers in the first cine frame and thereafter the computer advances the film and locates the markers. The markers are recognized based on positional information from the previous cine frame and on a video density profile. This system greatly reduced the investigators' time required for data analysis.