Friedrich Moritz, of Germany, introduced orthodiagraphy of the heart in which the central rays only of the X-ray beam were displaced around the contours of the heart on a fluoroscopic screen. Then the outline of the heart in systole and diastole were traced by hand. By fixing, at the same time major anatomic references such as the outline of the body, the ribs, the diaphragm,etc, the orientation of the heart could be calculated accurately. This instument was designed to obtain more precise measurements of the size of the heart compared to Rontgen X-ray that would show a shadow of the heart on the screen. The same instrument was also used to evaluate the size and the position of the aorta.
Moritz reported the use of orthodiography in pathological conditions such as in valvular heart disease and in aortic aneurysms.