Image Quality Study of Radiation-Reduced Combined Chest and Abdomen/Pelvis CT Compared With a Standard Protocol.

Abstract

The purpose of this study is to examine radiation doses and image quality of a low-dose (LD) protocol for chest and abdomen/pelvis (CAP) CT compared with a standard (STD) protocol. A total of 361 patients were included between October 2019 and April 2020; 104 patients with LD-protocol (100\xa0kV, ref mAs 80 (chest)/145 (abdomen/pelvis)) and 257 patients with STD-protocol (100\xa0kV, ref mAs 100 (chest)/180 (abdomen/pelvis)) at second-generation dual-source CT. Radiation doses for CTDIvol and DLP, and objective and subjective image qualities of 50 examinations from each group were evaluated. The LD-protocol applied significantly lower radiation doses compared with the STD-protocol (p\xa0<\xa00.001), achieving a dose reduction by 37% for the median DLP in chest, 19% in abdomen/pelvis and 22% in total. Median total DLP was 342\xa0mGy·cm (LD) vs. 436\xa0mGy·cm (STD). The LD-CAP CT protocol achieved a significant dose reduction far below national diagnostic reference levels, ensuring acceptable and good image quality.