Attenuation-Based Automatic Kilovoltage Selection and Sinogram-Affirmed Iterative Reconstruction: Effects on Radiation Exposure and Image Quality of Portal-Phase Liver CT

作者：Song Ji Soo^*; Choi Eun Jung; Kim Eun Young; Kwak Hyo Sung; Han Young Min

来源：Korean Journal of Radiology, 2015, 16(1): 69-79.

DOI：10.3348/kjr.2015.16.1.69

• Computed tomography
• Tube potential
• Iterative reconstruction
• Radiation dose reduction
• Image quality

Objective: To compare the radiation dose and image quality between standard-dose CT and a low-dose CT obtained with the combined use of an attenuation-based automatic kilovoltage (kV) selection tool (CARE kV) and sinogram-affirmed iterative reconstruction (SAFIRE) for contrast-enhanced CT examination of the liver.
Materials and Methods: We retrospectively reviewed 67 patients with chronic liver disease in whom both, standard-dose CT with 64-slice multidetector-row CT (MDCT) (protocol A), and low-dose CT with 128-slice MDCT using CARE kV and SAFIRE (protocol B) were performed. Images from protocol B during the portal phase were reconstructed using either filtered back projection or SAFIRE with 5 different iterative reconstruction (IR) strengths. We performed qualitative and quantitative analyses to select the appropriate IR strength. Reconstructed images were then qualitatively and quantitatively compared with protocol A images.
Results: Qualitative and quantitative analysis of protocol B demonstrated that SAFIRE Level 2 (S2) was most appropriate in our study. Qualitative and quantitative analysis comparing S2 images from protocol B with images from protocol A, showed overall good diagnostic confidence of 52 images despite a significant radiation dose reduction (47% dose reduction, p < 0.001).
Conclusion: Combined use of CARE kV and SAFIRE allowed significant reduction in radiation exposure while maintaining image quality in contrast-enhanced Liver CT.

• 出版日期2015-2