Recent developments in transverse-jection (

The object of transverse-section gamma-ray imaging is to display the concentration of radioactive material in a thin transverse slice of the body. The technique is essentially that of reconstructing an in-plane density distribution picture from the linear-scan intensity profiles measured at regular angular increments within the plane. This paper describes the results obtained from the use of three different mathematical methods of section image reconstruction - back projection, the convolution method of Bracewell and Riddle, and the linear integral transform method of Radon. The section picture computations were carried out using a universal minicomputer. The methods of Bracewell and Riddle, and Radon were found to give the most accurate reconstructions, at the expense of longer computational times. The usefulness of the isotope section scanning technique for clinical diagnosis is illustrated by recent data obtained with the Aberdeen section scanner and the J and P tomographic scanner