Approximate Theoretical Solution of a problem of Scattering of Soft X rays (λ Between 0·25 and 0·56 Å) and its Consequences in Medical Radiology

Abstract

(A) Statement of a physical problem of X ray scattering. Fundamentals of an approximate theoretical solution of the problem. Test of the solution by comparison with experimental data. (B) Discussion of the requirements of superficial X-ray therapy. Survey of a method to establish rational techniques of X-ray therapy in skin diseases. (C) Evaluation of densities and contrasts in radiographs of a typical object. Discussion of the changes in the image resulting from three different changes of the technique of exposure, viz.: (a) use of a film with greater gradation, (b) reduction of the size of the beam, (c) increase of wavelength of the X radiation. It is found that change (a) enlarges all contrasts in the same proportion, that change (b) enlarges all contrasts, but preferably those in the lighter regions of the image, and that (c) gives a considerable enlargement of contrasts in the darker regions of the image whereas it reduces the contrasts in the lighter regions.