Feasibility of low-concentration iodinated contrast medium with lower-tube-voltage dual-source CT aortography using iterative reconstruction: comparison with automatic exposure control CT aortography

• DOI: 10.1007/s10554-015-0816-6
• Publication Date: 2015-11-29T23:31:51Z
• Authors: Hee Jeong Shin; Song Soo Kim; Jae-Hwan Lee; Jae-Hyeong Park; Jin-Ok Jeong; Seon Ah Jin; Byung Seok Shin; Kyung-Sook Shin; Moonsang Ahn
• Keywords: Adult; Male; 2. Zero hunger; Computed Tomography Angiography; Aortic Diseases; Contrast Media; Middle Aged; Radiation Exposure; Signal-To-Noise Ratio; Radiation Dosage; Aortography; Iopamidol; Automation; 03 medical and health sciences; 0302 clinical medicine; Predictive Value of Tests; Triiodobenzoic Acids; Feasibility Studies; Humans; Radiographic Image Interpretation, Computer-Assisted; Female; Aorta; Aged

To evaluate the feasibility of low-concentration contrast medium (CM) for vascular enhancement, image quality, and radiation dose on computed tomography aortography (CTA) using a combined low-tube-voltage and iterative reconstruction (IR) technique. Ninety subjects underwent dual-source CT (DSCT) operating in dual-source, high-pitch mode. DSCT scans were performed using both high-concentration CM (Group A, n = 50; Iomeprol 400) and low-concentration CM (Group B, n = 40; Iodixanol 270). Group A was scanned using a reference tube potential of 120 kVp and 120 reference mAs under automatic exposure control with IR. Group B was scanned using low-tube-voltage (80 or 100 kVp if body mass index ≥25 kg/m(2)) at a fixed current of 150 mAs, along with IR. Images of the two groups were compared regarding attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), iodine load, and radiation dose in various locations of the CTA. In comparison between Group A and Group B, the average mean attenuation (454.73 ± 86.66 vs. 515.96 ± 101.55 HU), SNR (25.28 ± 4.34 vs. 31.29 ± 4.58), and CNR (21.83 ± 4.20 vs. 27.55 ± 4.81) on CTA in Group B showed significantly greater values and significantly lower image noise values (18.76 ± 2.19 vs. 17.48 ± 3.34) than those in Group A (all Ps < 0.05). Homogeneous contrast enhancement from the ascending thoracic aorta to the infrarenal abdominal aorta was significantly superior in Group B (P < 0.05). Low-concentration CM and a low-tube-voltage combination technique using IR is a feasible method, showing sufficient contrast enhancement and image quality.