能谱CT最佳单能量技术优化头颈部CTA图像质量的研究

Spectral CT with Optimal Monochromatic Energy to Improve CTA Image Quality of Head and Neck

目的:探讨能谱CT最佳单能量技术提高头颈部CTA图像质量的价值。方法:选取2016年2月至2017年12月期间收治的60例疑似患有头颈部血管疾病的患者,进行能谱CT头颈部减影CTA检查。获得最佳单能量、常规混合能量两组减影图像,测量两组主动脉弓、颈总动脉末端、大脑中动脉M1段的CT值;计算两组图像信噪比(SNR)、对比噪声比(CNR);对两组血管质量进行主观质量评分;并比较两组之间的差异性。结果:最佳单能量组、常规混合能量组在主动脉弓层面,平均CT值分别为445.25±105.45、283.88±71.96;在颈总动脉末端层面,平均CT值分别为444.00±96.02、350.38±76.40;在大脑中动脉M1段层面,平均CT值分别为375.00±73.78、280.00±55.12;差异均有统计学意义。两组图像SNR分别为62.01±39.56、31.36±17.35;CNR分别为60.46±39.19、30.10±16.80;差异有统计学意义;两组图像主观质量评分比较,差异有统计学意义。结论:能谱CT最佳单能量减影CTA较常规混合能量减影CTA,具有更高的血管CT值、SNR、CNR、主观质量评分,可提高头颈部血管CTA质量,优化血管的显示。

Objective: To evaluate the value of spectral CT with optimal monochromatic energy to improve the CTA image quality of head and neck. Methods: A total of 60 patients with suspected head and neck vascular diseases admitted to our hospital from February 2016 to December 2017 were selected for subtraction spectral CTA of neck and neck. Two subtraction images of the optimal monochromatic energy and conventional mixed energy were obtained, and arterial attenuation of the aortic arch, the end of the common carotid artery and the M1 segment of the middle cerebral artery were measured, and the two groups of signal to noise ratio(SNR) and contrast to noise ratio(CNR) were calculated;the subjective quality score of the two groups were evaluated;The differences between the two groups were compared. Results: The mean attenuation values of the optimal monochromatic energy group and the conventional mixed energy group were 445.25 ± 105.45 and 283.88 ± 71.96 in the aortic arch, and the mean attenuation values were 444.00 ± 96.02 and 350.38 ± 76.40 at the end of the common carotid artery, and the mean attenuation values were 375.00 ± 73.78 and 280.00 ± 55.12 in the M1 segment of the middle cerebral artery, and there were significant differences among the three of them. The SNR of the two groups were 62.01 ± 39.56 and 31.36 ± 17.35, and the CNR were 60.46 ± 39.19 and 30.10 ± 16.80,respectively;and there were significant differences among the two of them, and there were significant differences in the subjective quality score of the two groups of images. Conclusion: The spectral CT with optimal monochromatic energy subtraction CTA is better than the conventional mixed energy subtraction CTA. It has higher arterial attenuation, SNR, CNR, and subjective quality score, which can improve the image quality of head and neck angiography and optimize the display of arteries.