[New method of estimating x-ray magnification on angiographic volume determinations (author's transl)]

1. The necessity of a precise determination of the magnification factor for angiographic volume determinations is described. Each error of the linear magnification factor influences in its third power the volume calculation. 2. For the magnification of linear cineangiographic magnification a method is used in which the tip of the catheter is filmed in two positions. The distance approximately resembles a normal ventricular diameter. The relationship of virtuel shifting of the catheter tip versus real shifting of the patient is the magnification factor. 3. For the practicable handling of this method a new developed mechanical device is described which allows the performance of the calibration procedure with an adequate high precision. 4. The method is simple and can be done within a short period of time.