Adaptive pulse rate scheduling for reduced dose X-ray cardiac interventional fluoroscopic procedures

Presents an approach for reducing X-ray absorbed dose during cardiac fluoroscopic interventional procedures. The approach hinges on two main concepts: (1) adapting the X-ray pulse rate to the activity of the organ under investigation (the heart); and (2) maintaining the appearance of a 30-frame/s display rate to the viewer. The first concept was accomplished through the processing of multiple sensor information to determine the onset of the various phases of ventricular motion within the cardiac cycle. For each detected phase of the cardiac cycle, a specific tube pulse rate is assigned or automatically determined (after a learning period) such that high activity phases will have higher tube rate than phases with low activity. In order to maintain a 30-frame/s display rate to the viewer, a last-frame-hold approach was used and the resultant sequence shows minimal jerkiness artifacts as a result of the adaptive-motion-dependent sampling strategy. Preliminary results of the proposed system indicate the possibility of a three-to-one reduction of the tube pulse-rate. This translates to a dose reduction of a similar ratio.<<ETX>>