Computer enhancement of direct and venous-injected left ventricular contrast angiography

摘要: Abstract Following peripheral venous injection of radiopaque contrast material, a new on-line automatic computer image enhancement technique was employed to delineate the left ventricular (LV) endocardial silhouette in 10 dogs and 8 patients. This employs very fast analog-to-digital conversion system capable digitizing video frames on-line. By averaging into digital memory first 30 then subtracting each incoming frame from this memory, most background is eliminated, leaving only contrast-filled ventricle. Since conventional fluoroscopic exposure rates rather than cineangiography, there marked reduction xray exposure. An vitro study using Rando whole body phantom demonstrated that 5 mm object with 2% could be imaged within complex chest anatomy an incident rate mR/sec, subtraction followed by enhancement. In vivo studies were performed assess relative accuracy border definition comparison unenhanced images eight The difference planmetered area two cardiac silhouettes 13 ± 4 2 (mean 3.4%). four patients both direct LV angiograms obtained. There small (2% 7%) systematic between calculated end-diastolic end-systolic volume, volumes invariably being smaller. Differences ejection fraction (EF) smaller magnitude; maximum absolute EF 2%. We conclude applicable angiographic involving either or vascular allows high quality obtained at approximately seven-fold radiation dose (5 mA, 65 85 kv).