Application of Forward Projected Model-Based Iterative Reconstruction Solution in
Low-Dose Coronary CTA
WANG Ming1，MA Zhuangfei2，ZHU Yaxin2，WANG Yun1，FU Haihong1，WANG Yining1，JIN Zhengyu1
1. Department of Radiology, Peking Union Medical College Hospital, Beijng 100730, China丨
2. Canon Medical System (China) Co., Ltd., Beijing 100015, China
Abstract：Objective To investigate forward projected model-based iterative reconstruction solution (FIRST) in low-dose coronary
CTA. Methods Forty five patients with 80 kV low-dose coronary CTA scanning using Aquilion ONE GENESIS 640 slices CT
were included in this study. The mean body mass index was (24.7±2.7) kg/m2, and the heart rate was less than 75 beats/min.
The original scanned data were reconstructed by FIRST_Cardiac, adaptive iterative dose reduction 3D and filtered back projection
algorithm. The value of CT value and image noise standard deviation (SD) of lumen and adjacent fat components were measured
in aortic root, left main artery, proximal, middle and distal anterior descending branch, proximal and distal circumconvolutional
branch, and proximal, middle and distal segments of right coronary artery, and signal to noise ratio (SNR) and contrast to noise ratio
(CNR) were calculated. CT and SD values of right coronary artery, anterior descending artery and circumflex artery were calculated
by averaging the proximal, middle and distal segments. Double blind method was used to evaluate the image quality of 18 segments
of coronary artery by 4-point method. Dose-length product and CT volumetric dose index were recorded and the effective radiation
dose was measured. Results There were no significant differences in CT values of right coronary artery, anterior descending artery,
circumflex artery, aortic root and left main artery among the three groups (P=0.438, 0.280, 0.292, 0263 and 0.409, respectively).
The SD values of FIRST_Cardiac images were significantly lower than those of the other two groups (P<0.001). SNR, CNR and
subjective image quality scores of FIRST_Cardiac images were significantly higher than those of the other two groups (P<0.001).
Conclusion FIRST can significantly reduce the image noise of 80 kV low-dose coronary CTA, improve image quality, and satisfy the
clinical diagnosis.
