A.S. Takahashi – författare

If the early stages of a disease begin with the involvement of a small area of cells or tissue, the early diagnosis of pathologic changes by means of radio­ graphy should concentrate first on the detection of such minute changes. The ideal solution would be to produce X-ray images of findings much finer than those observable by the naked eye, and herein lies a new field of research that is believed to be worth developing. The introduction of a 0.3 mm focal-spot rotating-anode tube about 25 years ago opened the way to the clinical application of magnification radiography. Due to the postwar economic situation, we were unable to import this type of X-ray tube, but we believed in the importance of magnification radiography in X-ray diagnosis, and in 1952 we produced an X-ray tube with a 0.15 mm focal spot by reconstructing an existing fixed-anode tube. This X-ray tube has been improved step by step, so that tubes with focal spots of 0.1 mm or 0.05 mm are now available in Japan. Thus it has become possible to obtain 4 to 6 x magnification images of minute lesions that could not be imaged by normal roentgenography.

If the early stages of a disease begin with the involvement of a small area of cells or tissue, the early diagnosis of pathologic changes by means of radio­ graphy should concentrate first on the detection of such minute changes. The ideal solution would be to produce X-ray images of findings much finer than those observable by the naked eye, and herein lies a new field of research that is believed to be worth developing. The introduction of a 0.3 mm focal-spot rotating-anode tube about 25 years ago opened the way to the clinical application of magnification radiography. Due to the postwar economic situation, we were unable to import this type of X-ray tube, but we believed in the importance of magnification radiography in X-ray diagnosis, and in 1952 we produced an X-ray tube with a 0.15 mm focal spot by reconstructing an existing fixed-anode tube. This X-ray tube has been improved step by step, so that tubes with focal spots of 0.1 mm or 0.05 mm are now available in Japan. Thus it has become possible to obtain 4 to 6 x magnification images of minute lesions that could not be imaged by normal roentgenography.

In spring this year it will be 23 years since I began to study rotation technique as applied to radiology. In applying this technique to roentgenography the name Rotation Radiography was adopted publicly in 1946. Since then this study has revealed that the technique is valuable not only in diagnosis but also in radiotherapy, and the name Conformation Radiotherapy was publicly an­ nounced in 1960. Through these studies it became clear that it is possible to show the axial transverse cross section of the human body roentgenographically, which could be of great value medically, but it was realized that no detailed roentgenograms of the axial transverse cross section covering the whole of the normal human adult have been published so far. To prepare an atlas was therefore considered basic for the practical application of this method, since without it further developments of this type of roentgenography cannot be expected. Conse­ quently it was decided first to prepare the atlas. In addition, the clinical application of this method to the diagnostic and therapeutic field was described with brief notes on the essential features of the method.