能谱CT单能量成像优化腹部增强中腹腔干成像质量的探究

An Investigation of Single-Energy Imaging with Energy-Spectrum CT to Optimise the Quality of Abdominal Stem Imaging in Abdominal Enhancement

摘要: 目的：比较在腹部增强扫描中能谱CT单能量图像质量和常规扫描图像质量，探讨能谱CT单能量成像技术对腹腔干优化显示的应用价值。方法：搜集110例行腹部CT增强扫描的患者，随机分成两组，能谱扫描组55例进行能谱增强扫描，重建出50 keV、60 keV、70 keV的3组单能量图像和1组120 kVp-like混合能量图像；常规扫描组55例采用常规增强扫描作为对照组。分别记录能谱扫描组四组和对照组各组腹腔干起始部及同层面竖脊肌的CT值，计算SNR和CNR，记录能谱扫描组和对照组的辐射剂量。结果：单能量图像各组间的CT值、SNR、CNR差异有统计学意义(P < 0.001)，且随着能级的降低，CT值、SNR、CNR呈递增趋势；120 kVp-like和对照组的CT值、SNR、CNR差异无统计学意义(P > 0.05)；70 keV和120 kVp-like的SNR、CNR差异无统计学意义(P > 0.05)；50 keV图像主观评分最高，与各组间差异有统计学意义(P < 0.001)。结论：与常规CT扫描相较，能谱CT利用单能量成像进行血管成像时拥有更高的图像质量，50 keV时腹腔干显示最佳，拥有更高的CT值以及更好的SNR、CNR。

Abstract: Objective: To compare the quality of single-energy images of energy-spectrum CT with that of conventional scans in abdominal enhancement scanning, and to explore the application value of single-energy imaging technology of energy-spectrum CT for the optimal display of celiac axis. Methods: 110 cases of abdominal CT enhancement scanning were collected and randomly divided into two groups: 55 cases in the energy spectrum scanning group underwent energy spectrum enhancement scanning to reconstruct three sets of single-energy images of 50 keV, 60 keV, 70 keV and one set of 120 kVp-like mixed-energy images; 55 cases in the conventional scanning group were used in the conventional enhancement scanning as the control group. The CT values of the beginning of the celiac axis and the erector spinae muscle at the same level in each of the four groups of the energy spectrum scanning group and the control group were recorded respectively, the SNR and CNR were calculated, and the radiation doses in the energy spectrum scanning group and the control group were recorded. Results: The differences in CT values, SNR and CNR between the groups of single-energy images were statistically significant (P < 0.001) and tended to increase with decreasing energy levels; the differences in CT values, SNR and CNR between the 120 kVp-like and control groups were not statistically significant (P > 0.05); the 70 keV and 120 kVp-like SNR, CNR differences were not statistically significant (P > 0.05); 50 keV images had the highest subjective scores, with statistically significant differences between the groups (P < 0.001). Conclusion: Compared with conventional CT scanning, energy-spectrum CT has higher image quality when using single-energy imaging for vascular imaging, and the celiac axis is best displayed at 50 keV, with higher CT values and better SNR and CNR.