迭代重建技术在低辐射剂量头颈部CT血管成像中的应用

Application of iterative reconstruction technique in CT angiography of head and neck with low radiation dose

目的探讨迭代重建技术在低辐射剂量头颈部CT血管成像(CTA)中对图像质量以及辐射剂量的影响。方法采用前瞻性随机对照研究的方法,选取2017年2月至2018年3月沧州市中心医院收治的进行头颈部CTA检查的患者80例,以简单化随机分组的方法将患者平均分为两组,每组各40例。观察组患者选择iDOSE迭代重建算法,对照组患者选择滤波反投影重建算法。对比两组患者的不同动脉的CT值、主观图像质量评分以及剂量长度乘积(DLP)、CT容积剂量指数(CRDIvol)、有效剂量(ED)。结果观察组患者的主动脉、颈动脉、颈内动脉的CT值分别为(353.84±51.39)HU、(398.18±63.16)HU、(338.15±52.54)HU,对照组患者主动脉、颈动脉、颈内动脉的CT值分别为(371.18±52.27)HU、(392.86±61.35)HU、(335.96±56.67)HU。观察组患者不同动脉的CT值与对照组患者相比,差异无统计学意义(P>0.05)。观察组患者的主观图像质量评分为(4.42±0.35)分,相比对照组的(4.13±0.28)分明显提高,差异具有统计学意义(P<0.05)。观察组患者的DLP为(267.35±11.57)mGy·cm,CTDIvol为(6.75±0.68)mGy,ED为(1.54±0.17)mSv;对照组DLP为(1269.31±152.43)mGy·cm,CTDIvol为(31.72±3.17)mGy,ED为(7.58±0.23)mSv。观察组患者的DLP、CTDIvol、ED均明显低于对照组,差异具有统计学意义(P<0.05)。结论iDOSE迭代重建图像技术能够有效改善头颈部CTA检查的图像质量,同时可以明显降低CT检查的辐射剂量,具有较高的临床应用价值。

Objective To investigate the effect of iterative reconstruction technique on image quality and radiation dose in low-dose head and neck CT angiography (CTA). Methods This is a prospective randomized controlled trial. 80 patients with head and neck CTA who were admitted to the Central Hospital of CangZhou from February 2017 to March 2018 were enrolled. The patients were divided into two groups by simple randomization. 40 cases in each group. The observation group patients selected the iDOSE iterative reconstruction algorithm,and the control group patients selected the filtered back projection reconstruction algorithm. CT values,subjective image quality scores,and dose length product (DLP),CT volume dose index (CRDIvol),and effective dose (ED) of different arteries were compared between the two groups. Results CT values of the aorta,carotid artery and internal carotid artery in the observation group were (353.84±51.39) HU,(398.18±63.16) HU,(338.15±52.54) HU,and (371.18±52.27) HU,(392.86±61.35) HU,(335.96±56.67) HU,respectively. There was no significant difference in CT value between the observation group and the control group ( P >0.05). The subjective image quality score of the observation group was (4.42±0.35),which was significantly higher than that of the control group (4.13±0.28)( P <0.05). In the observation group,DLP,CTDIvol,and ED were (267.35±11.57) mGy·cm,(6.75±0.68) mGy,and (1.54±0.17) mSv. In the control group,DLP was (1 269.31±152.43) mGy·cm,CTDIvol was (31.72±3.17) mGy,ED was (7.58±0.23) mSv. DLP,CTDIvol and ED in the observation group were significantly lower than those in the control group ( P <0.05). Conclusion iDOSE iterative image reconstruction technology can effectively improve the image quality of head and neck CTA examination,and significantly reduce the radiation dose of CT examination,so it has high clinical value.