Reducing both radiation and contrast doses in coronary CT angiography in lean patients on a 16-cm wide-detector CT using 70 kVp and ASiR-V algorithm, in comparison with the conventional 100-kVp protocol

• Published in: European radiology Vol. 29; no. 6; pp. 3036 - 3043
• Main Authors: Chen, Yuhuan, Liu, Zhentang, Li, Michelle, Yu, Yong, Jia, Yongjun, Ma, Guangming, Hu, Zhijun, Wei, DongHong, Li, Dou, He, Taiping
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.06.2019; Springer Nature B.V
• Subjects: Adaptive algorithms; Adaptive systems; Adult; Aged; Algorithms; Angiography; Body mass; Body Mass Index; Body size; Cardiac; Clinical Protocols; Computed tomography; Computed Tomography Angiography - methods; Contrast Media - administration & dosage; Coronary Angiography - methods; Demographics; Demography; Diagnostic Radiology; Diagnostic systems; EKG; Electrocardiography - methods; Female; Humans; Image contrast; Image quality; Image reconstruction; Imaging; Injection; Internal Medicine; Interventional Radiology; Male; Medical imaging; Medicine; Medicine & Public Health; Middle Aged; Neuroradiology; Noise; Prospective Studies; Radiation; Radiation Dosage; Radiographic Image Interpretation, Computer-Assisted - methods; Radiology; Radionuclide Imaging; Sensors; Statistical analysis; Thinness; Ultrasound; Computed tomography angiography; Coronary angiography; Radiation dosage; Contrast media
• ISSN: 0938-7994; 1432-1084; 1432-1084
• DOI: 10.1007/s00330-018-5837-9

Objective To investigate the value of prospectively ECG-triggered coronary CT angiography (CCTA) for lean patients with body mass index (BMI) ≤ 23 kg/m 2 using 70 kVp and high-level volume-based adaptive statistical iterative reconstruction (ASiR-V) algorithm on a 16-cm wide-detector CT system for reducing both radiation and contrast doses in comparison with the conventional 100-kVp protocol. Materials and methods Thirty patients (group A) were prospectively enrolled to undergo 70-kVp CCTA on a 16-cm wide-detector CT scanner with noise index (NI) of 36 HU and at weight-dependent contrast dose rate of 16 mg I/kg/s for 9-s injection. Images were reconstructed with 80% ASiR-V. Radiation dose, contrast dose, and image quality were statistically compared with 30 patients (group B) in database with matching BMI who underwent conventional 100-kVp CCTA with NI of 25 HU, and at 25 mg I/kg/s rate for 10-s injection and reconstructed with 60% ASiR-V. Results There was no significant difference in patient demographics between the two groups (all p  > 0.05). The two groups also had similar mean CT values and contrast-noise ratio (CNR) and subjective image quality (all p  > 0.05). However, group A with 70 kVp reduced the effective dose by 75.3% compared with group B (0.43 ± 0.20 mSv vs. 1.74 ± 1.01 mSv, p  < 0.001), and required 42.4% less contrast dose than group B (22.46 ± 2.94 ml vs. 38.99 ± 5.10 ml, p  < 0.001). Conclusions Prospectively ECG-triggered CCTA using 70 kVp and high-level ASiR-V on a 16-cm wide-detector CT system provides diagnostic images with substantial reduction in both radiation and contrast doses for patients with BMI ≤ 23 kg/m 2 compared to the conventional 100-kVp protocol. Key Points • 70-kVp CCTA produces excellent images at sub-millisievert radiation. • 70-kVp CCTA reduces both radiation and contrast doses over conventional protocol. • Achieving low-dose CCTA with combined low kVp and high-level ASIR-V.