The paper is concerned with retrospective analysis of investigations of 1000 patients for standardization of the methodology of computerized subtraction angiography (CSA). Intravenous injection of a contrast medium for visualization of various parts of the arterial system was performed in 374 patients, a selective contrast study of the arteries and veins--in 626. Optimum regimens of injections of a contrast medium, the rate of injection with respect to the site of drug administration, the internal section and length of a catheter were determined. Correlation between a single dose of injection of a contrast medium and the patient's body mass during i. v. CSA was determined. Shortcomings of the method and possibilities for their elimination were mentioned. Some methodological procedures for CSA optimization (a possibility of correlation of the detected changes with anatomical structures and the determination of their actual sizes irrespective of the size of an image obtained) were proposed.