Probability of receiving a high cumulative radiation dose and primary clinical indication of CT examinations: a 5-year observational cohort study.

Objective: High radiation exposure is a concern because of the association with cancer. The objective was to determine the probability of receiving a high radiation dose from CT (from one or more examinations within a 5-year period) and to assess the clinical context by evaluating clinical indications in the high-dose patient group.

Design: Observational cohort study.

Implementation of Size-Dependent Local Diagnostic Reference Levels for CT Angiography.

Objective: Diagnostic reference levels (DRLs) are established for standard-sized patients; however, patient dose in CT depends on patient size. The purpose of this study was to introduce a method for setting size-dependent local diagnostic reference levels (LDRLs) and to evaluate these LDRLs in comparison with size-independent LDRLs and with respect to image quality.

Materials And Methods: One hundred eighty-four aortic CT angiography (CTA) examinations performed on either a second-generation or third-generation dual-source CT scanner were included; we refer to the second-generation dual-source CT scanner as "CT1" and the third-generation dual-source CT scanner as "CT2.