Adaptive Statistical Iterative Reconstruction: Assessment of Image Noise and Image Quality in Coronary CT Angiography
Adaptive Statistical Iterative Reconstruction: Assessment of Image Noise and Image Quality in Coronary CT Angiography
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DOI：
10.2214/ajr.10.4285
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发表时间：
2010-09-01
影响因子：
5
通讯作者：
Earls, James P.
中科院分区：
文献类型：
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作者：
Leipsic, Jonathon;LaBounty, Troy M.;Earls, James P.
OBJECTIVE.本研究的目的是确定自适应统计迭代重建（ASIR）对心脏CT血管造影（CTA）信号、噪声和图像质量的影响。我们评估了三个研究中心的62名连续患者，这些患者使用具有ASIR功能的64-MDCT扫描仪和低剂量心脏CTA技术进行了临床指征心脏CTA。使用滤波反投影（FBP）、使用20-80% ASIR和100% ASIR的ASIR-FBP复合物重建研究。在主动脉根部和四个冠状动脉中的每一个中测量信号和噪声。两名设盲的阅片员采用5分制Likert量表对图像质量进行分级，并确定可解释片段的比例。无论大小，均纳入所有节段进行分析。与FBP（0% ASIR）相比，使用20%、40%、60%、80%和100% ASIR导致组间图像噪声降低（分别为-7%、-17%、-26%、-35%和-43%; p < 0.001），信号无差异（p = 0.60）。组间差异有显著性（0%、20%、40%、60%、80%和100% ASIR）（分别为1.5、2.1、3.7、3.8、2.0和1.1; p < 0.001）和可解释片段的比例（分别为88.7%、89.3%、90.5%、90.4%、88.0%和87.3%; p < 0.001）。使用40%和60%ASIR重建具有最高的Likert评分和最大比例的可解释片段。与FBP相比，每种均与更高的Likert评分和更多的可解释片段相关（所有P < 0.001）。ASIR降低了噪声，并显著影响了图像质量。当使用低管电流技术时，与FBP重建相比，使用40%或60% ASIR的心脏CTA重建显著改善了图像质量和可解释片段的比例。
OBJECTIVE. The purpose of our study was to determine the effect of Adaptive Statistical Iterative Reconstruction (ASIR) on cardiac CT angiography (CTA) signal, noise, and image quality.Materials and Met hods. We evaluated 62 consecutive patients at three sites who underwent clinically indicated cardiac CTA using an ASIR-capable 64-MDCT scanner and a low-dose cardiac CTA technique. Studies were reconstructed using filtered back projection (FBP), ASIR-FBP composites using 20-80% ASIR, and 100% ASIR. The signal and noise were measured in the aortic root and each of the four coronary arteries. Two blinded readers graded image quality on a 5-point Likert scale and determined the proportion of interpretable segments. All segments were included for analysis regardless of size.RESULTS. In comparison with FBP (0% ASIR), the use of 20%, 40%, 60%, 80%, and 100% ASIR resulted in reduced image noise between groups (-7%, -17%, -26%, -35%, and -43%, respectively; p < 0.001) without difference in signal (p = 0.60). There were significant differences between groups (0%, 20%, 40%, 60%, 80%, and 100% ASIR) in the Likert scores (1.5, 2.1, 3.7, 3.8, 2.0, and 1.1, respectively; p < 0.001) and proportion of interpretable segments (88.7%, 89.3%, 90.5%, 90.4%, 88.0%, and 87.3%, respectively; p < 0.001). Reconstruction using 40% and 60% ASIR had the highest Likert scores and largest proportion of interpretable segments. In comparison with FBP, each was associated with higher Likert scores and increased interpretable segments (p < 0.001 for all).CONCLUSION. ASIR resulted in noise reduction and significantly impacted image quality. When using a low tube current technique, cardiac CTA reconstruction using 40% or 60% ASIR significantly improved image quality and the proportion of interpretable segments compared with FBP reconstruction.