Technik der herstellung fast orthodiagraphischer herzphotogramme vermittelst rontgeninstrumentarien mit kleiner elektrizitatsquelle. Wien Klin Rdsch., 1905,19,279-82.
Rontgenology, the borderlands of the normal and early pathological in the skiagram, New York, William Wood and Company, 1928.
Alban Kohler was a German physician and studied at the University of Berlin. He was a pioneer in radiology and performed the first telerontgenogram (chest X-ray) as shown below in 1903. His contributions are regarded among the most important of the first decades of radiology.
Kohler introduced the technique of teleradiography to achieve improved X-ray visualization of the heart in 1905. During teleradiography, the patient and film were placed 3m from the tube (not less than 1.5m), a distance significantly greater than used for fluoroscopy. The size and the shape of the heart were then recorded on a chest film. The motion of the heart in systole and diastole could be visualized by kymography.
This new procedure excluded the personal factor of the operator which was indispensable in orthodiagraphy. Kohler stated that the margin of error by experienced orthodiagraphers in calculating the size of the heart was about 1-2 cm whereas this margin was reduced to less than 3mm in teleradiography.
His textbook entitled, "Rontgenology, the borderlands of the normal and early pathological in the skiagram," appeared in 1928. The first German edition was published in 1910. It was considered a reference book because of its clarity and the detailed description of normal and pathological conditions.
In his monograph, he provided a detailed description of the forms and size of the normal heart as well as enlarged heart using simple illustrations. in his text, Kohler wrote:
"...the Rontgen picture of perfectly healthy adults shows us... a wonderful variety in the form and size of the heart...Yet it is not so much the heart alone as the varying positions of the heart and the thoracic cavity that produces the manifold differences in the shadow picture. For a heart even of the self-same size and form will give in a narrow thorax quite a different picture from what it gives in a squat thorax, a different picture in inspiration from that in expiration, in the vertical from that in horizontal, a different picture in the prone position from that in the dorsal decubitus, quite apart from the different amount of filling by the blood; for the heart is suspended above by the vessels and rests upon the diaphragm."
The entire text of this section, "Adult heart", is reproduced here.
He also described the alterations of the form and the size of the heart in pathologic conditions including in the presence of valvular heart disease. Of great interest are pages 352-356 dealing with alterations of cardiac size and form in the setting of mitral valve disease:
"An almost constant feature in mitral stenosis is the definite enlargement of the volume of the left auricle with an ovoid form of the heart shadow and without any marked enlargement of the heart shadow. Dilatations of the left auricle with marked systolic pulsation and rounded from the heart with evident enlargement of the cardiac shadow, are almost certainly ascribable to mitral insufficiency."