Xeroradiography of the bones, joints, and soft tissues.

Abstract

xeroradiography (the technic of using photoconductors and electrostatic charges as a method of recording x-ray images) of the peripheral parts of the body has certain distinct advantages over conventional film technics. To be sure, it is not perfect, and there are some disadvantages, but none are serious, nor do they detract significantly from the efficacy of the method. Xeroradiography is an unfamiliar but not completely new method of investigation, and a few papers by various workers have appeared in the literature, including those by Campbell (1), Hills (2), McMaster (3), Nagami (4), Oliphant (5), and Roach and Hilleboe (6). These authors have noted the convenience of xeroradiography and the great detail and high resolution obtainable by the method. Less optimistically, it has been reported that too much radiation is required to produce a xeroradiograph. When one considers the superior quality of the image obtained, however, less radiation may actually be required in routine work: fewer views are needed and perhaps fewer retakes are necessary because of errors in technic. I would disagree with previous reports of loss of fine bone detail and low contrast, as these phenomena are controlled readily by variations in kilo voltage. From observations made at Hutzel Hospital, I have found the main advantages of xeroradiography to be as follows: a. More information is obtainable from a single xeroradiograph than from a comparable film image. b. Differences in density, such as fracture lines or soft-tissue calcifications, are accentuated within the structure being examined. c. The technic has a great latitude of exposure factors, especially at low millam-perage and high kilovoltage. The xeroradiograph can record many tissues of different densities and thicknesses on a single image, for example, bone vs. fat, air vs. muscle, etc. On a lateral view of the cervical spine, one can see not only the primary areas of interest—the vertebrae— but also all of their finer parts such as the spinous processes, the lamina, and the articular facets. In addition, the dense areas at the base of the skull are shown—the bone structures of the face and their air spaces, the trachea, cartilages, epiglottis, valleculae, etc. All information is observable at a glance, either with reflected or transmitted light, depending on whether one uses translucent plastic or an opaque paper as the base for the xeroradiograph.