Effective Doses and Dose Reference Levels (DRLs) in a radiology department from a tertiary hospital

Abstract

One way to promote optimization in radiation protection is by implementing the concept of the Diagnostic Reference Level (DRL). There are several ways to estimate the radiation dose delivered to the patient, including the dose-area product (DAP) estimate. This study estimated diagnostic reference levels for common radiographic examinations performed in a large Brazilian hospital. For this, DAP data were collected and filtered for the standard patient model. All procedures evaluated were performed in conventional radiology equipment, including AP chest, LAT chest and PA chest, AP abdomen, AP pelvis and AP and LAT lumbar spine. The PCXMC 2.0 software was used in the computer simulation of radiographic exams to simulate the effective dose in the patient for the incidences used. In total, after checking the data, 167 DAP values were selected and the number of incidences performed ranged from 7 to 51 for different projections. The highest number of incidences were collected for the LAT thorax and the lowest number of incidences for the LAT lumbar spine. The 1st quartile, median and 3rd quartile were analyzed, as well as minimum and maximum DBH and the interquartile value (IQV) for each data set. The computer simulations resulted in effective dose values compatible with the international literature. As this is an initial work to survey the DRL, some points must be taken into account: the service is part of a teaching hospital with professionals in training; there are technical charts available. However, the digital equipment was recently installed; the study must be in-depth, with a greater number of each incidence, so that the protocols are well established in the service. This study serves as a reference for other services that wish to survey the diagnostic reference level for conventional radiology protocols.