Radiation dose and image quality of 70 kVp cerebral CT angiography with optimized sinogram-affirmed iterative reconstruction: comparison with 120 kVp cerebral CT angiography

• Published in: European radiology 2015-05, Vol.25 (5), p.1453-1463
• Main Authors: Chen, Guo Zhong, Zhang, Long Jiang, Schoepf, U. Joseph, Wichmann, Julian L., Milliken, Cole M., Zhou, Chang Sheng, Qi, Li, Luo, Song, Lu, Guang Ming
• Format: Article
• Language: English
• Subjects: Aneurysms; Carotid arteries; Carotid Artery, Internal - diagnostic imaging; Cerebral Angiography - methods; Contrast Media; Diagnostic Radiology; Female; Head and Neck; Humans; Imaging; Internal Medicine; Interventional Radiology; Iohexol - analogs & derivatives; Male; Medical imaging; Medicine; Medicine & Public Health; Middle Aged; Middle Cerebral Artery - diagnostic imaging; Neuroradiology; Prospective Studies; Radiation; Radiation Dosage; Radiographic Image Enhancement; Radiographic Image Interpretation, Computer-Assisted - methods; Radiology; Signal-To-Noise Ratio; Tomography; Tomography, X-Ray Computed - methods; Ultrasound; Veins & arteries
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-014-3533-y

Objectives To evaluate radiation dose, image quality, and optimal level of sinogram-affirmed iterative reconstruction (SAFIRE) of cerebral CT angiography (CTA) at 70 kVp. Methods One hundred patients were prospectively classified into two groups: Group A (n = 50), 70 kVp cerebral CTA with 5 levels of SAFIRE reconstruction (S1-S5); and Group B (n = 50), 120 kVp with filtered back projection (FBP) reconstruction. CT attenuation values, noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the internal carotid artery (ICA) and middle cerebral artery (MCA) were measured. Subjective image quality was evaluated. Effective dose (ED) was estimated. Results CT attenuation and noise of the ICA and MCA in Group A were higher than those of Group B (all P   0.05) or higher than in Group B ( P   0.05). ED was 0.2 ± 0.0 mSv for Group A with 85 % ED reduction in comparison to Group B (1.3 ± 0.2 mSv). Conclusion Cerebral CTA at 70 kVp is feasible, allowing for substantial radiation dose reduction. SAFIRE S4 level is recommended for obtaining optimal image quality. Key points • 70 kVp cerebral CTA is feasible and provides diagnostic image quality . • 70 kVp cerebral CTA resulted in 85  % effective dose reduction . • S4 level of SAFIRE is recommended for 70 kVp cerebral CTA .