Fig 1.
Study flowchart.
Table 1.
Patient characteristics and contrast agent.
Table 2.
Per-patient subjective image quality of abdominopelvic CT images in low- and high-concentration contrast agent groups.
Table 3.
Per-lesion subjective image quality of focal liver and renal lesions in low-concentration and high-concentration contrast agent groups.
Fig 2.
Abdominopelvic computed tomography (CT) images of patients with bladder and breast cancers.
CT images of a patient with bladder cancer (76-year-old, female; weight, 59.3 kg; body mass index, 25.0 kg/m2; a-b) and a patient with breast cancer (80-year-old, female; weight, 55 kg; body mass index, 25.8 kg/m2; c-d) with matching cases. (a-b) CT images show a left renal cyst (5 mm in size) using a low concentration of contrast agent and (c-d) a left renal cyst (4 mm in size) using a high concentration of contrast agent. The overall image quality score was 2 for the 80 kVp CT image (a), 3 for the 80/Sn 150 kVp image (b), 2 for the 80 kVp CT image (c), and 3 for the 80/Sn 150 kVp image (d). The renal lesion conspicuity and margin sharpness were similar, showing a score of 3 for conspicuity in all images (a-d), a score of 3 for margin sharpness in images (a) and (c), and a score of 4 in images (b) and (d).
Fig 3.
Abdominopelvic computed tomography (CT) images of two patients with breast cancers.
CT images of two patients with breast cancer (64-year-old, female; weight, 57.0 kg; body mass index, 21.7 kg/m2; a-b) vs (80-year-old, female; weight, 52 kg; body mass index, 23.1 kg/m2; c-d) with matching cases. (a-d) CT images show two hepatic cysts (arrows, 5 and 6 mm in size, respectively) using a low concentration of the contrast agent, and (e-f) two hepatic cysts (arrows, 5 and 7 mm in size, respectively) using a high concentration of the contrast agent. The overall image quality was scored 3 for the 80 kVp CT image (a and c), 4 for the 80/Sn 150 kVp image (b and d), 3 for the 80 kVp CT image (e), and 3 for the 80/Sn 150 kVp image (f). The conspicuity and margin sharpness of the hepatic lesions were similar, with a score of 4 for both parameters in all images.
Table 4.
Per-patient objective image quality in low-concentration and high-concentration contrast agent groups.
Table 5.
Radiation dose of CT scans in low- and high-concentration contrast agent groups.