PHANTOMS FOR DIAGNOSTIC-RADIOLOGY

To evaluate entrance skin exposure, the United States Food and Drug Administration (FDA), Center for Devices and Radiologic Health (CDRH), has developed patient-equivalent phantoms suitable for chest, abdominal and lumbosacral spine projections. Clinical trials performed by FDA have established the clinical equivalency of the exit X ray spectrum for a 23 cm chest thickness and 21 cm abdomen patient. Similarly, cylindrical Lucite head and body phantoms for computerised (axial) tomography have been developed and standards for their design and use have been published in the United States Code of Federal Regulations. The FDA has also conducted extensive surveys using these phantoms, and data is routinely published to establish a national average for comparison. These four phantoms are discussed and evaluated for use in routine clinical facilities. Their use by the European Community is suggested, and conformity, on an international scale, with existing US standards for reference is promoted.