Institutional computed tomography diagnostic reference levels based on water-equivalent diameter and size-specific dose estimates

S ize-specific institutional diagnostic reference levels (DRLs) were generated for chest and
abdominopelvic computed tomography (CT) based on size-specific dose estimates (SSDEs) and depending
on patients ’ water-equivalent diameter (Dw). 1690 CT examinations were included in the IRB-approved
retrospective study. SSDEs based on the mean water-equivalent diameter of the entire scan volume
were calculated automatically. SSDEs were analyzed for different patient sizes and institutional
DRLs (iDRLS; 75% percentiles) based on Dw and SSDEs were generated. iDRLs were compared to the
national DRLs. Mean volumetric computed tomography dose index (CTDIvol), Dw and SSDEs for all 1690
CT examinations were 7.2  ± 4.0 mGy (0.84–47.9 mGy), 29.0 ± 3.4 cm and 8.5 ± 3.8 mGy (1.2–37.7 mGy),
respectively. Overall, the mean SSDEs of all CT examinations were higher than the CTDIvol in chest
CT, abdominopelvic CT and upper abdominal CT, respectively (p  

Source: Journal of Radiological Protection - March 13, 2018 Category: Physics Authors: Johannes Boos, Christoph Thomas, Elisabeth Appel, Yan Klosterkemper, Christoph Schleich, Joel Aissa, Oliver Th Bethge, Gerald Antoch and Patric Kr öpil Source Type: research