Computed tomography scout views vs. conventional radiography in body-packers – Delineation of body-packs and radiation dose in a porcine model

Abstract

ObjectiveTo compare abdominal computed tomography (CT) scout views with conventional radiography regarding radiation dose and delineation of drug packages in a porcine body-packer model. Materials and methodsNine samples of illicit drugs packed in ovoid plastic containers were consecutively placed in the rectum of a 121.5kg pig cadaver. Antero-posterior and lateral scout views were obtained at 120kVp and 80mA, 150mA and 200mA, respectively, using a 64-row MDCT. Scout views were compared with conventional abdominal antero-posterior radiographs (77kV and 106±13mAs). Visibility of three body pack characteristics (wrapping, content, shape) was rated independently by two radiologists and summarized to a delineation score ranging from 0 to 9 with a score ≥6 representing sufficient delineation. Mean delineation scores were calculated for each conventional radiography and single plane scout view separately and for a combined rating of antero-posterior and lateral scout views. ResultsEven the lowest single plane scout view delineation score (5.3±2.0 for 80mA lateral; 0.4mSv; sensitivity=44%) was significantly higher than for conventional radiographs (3.1±2.5, p<0.001; 2.4±0.3mSv; sensitivity=11%). Combined reading of antero-posterior and lateral scout views 80mA yielded sufficient delineation (6.2±1.4; 0.8mSv; sensitivity=56%). ConclusionsAll CT scout views showed significantly better delineation ratings and sensitivity than conventional radiographs. Scout views in two planes at 80mA provided a sufficient level of delineation and a sensitivity five times higher than conventional radiography at less than one third of the radiation dose. In case of diagnostic insecurity, CT can be performed without additional logistical effort.