Barry Fredric Belanger

Clinical application of hybrid subtraction digital angiography: Preliminary results

The clinical application of hybrid subtraction in digital fluoroscopy of the vasculature is reported in our first 30 patients studied. Hybrid subtraction combines the advantages of temporal and dual energy subtraction techniques to achieve simultaneous elimination of overlying bone, soft tissue, and motion induced artifacts. Hybrid subtraction improved the subjective appearance of an image in 19 of 30 (63%) studies but additional diagnostic information was only revealed in 11 of 30 (37%) patients.

Hybrid Subtraction In Digital Fluorography

Digital fluorography using temporal subtraction techniques has achieved excellent visualization of the vascular anatomy with intravenous injections of contrast medium. However, clinical studies have demonstrated that a major limitation to this method is patient motion. Movements such as swallowing, breathing, peristalsis, cardiac motion, and arterial pulsations cause artifacts in difference images which can reduce the diagnostic accuracy of the procedure. Many of these artifacts can be eliminated by the use of hybrid subtraction, a second-order technique which combines temporal and dual-energy subtraction. This procedure is described and compared to both temporal and dual energy subtraction methods in terms of data acquisition, iodine signal-to-noise ratios, dose, and x-ray tube loading. Images are shown to demonstrate the viability of this new technique.