Li Lei, Zhao Fei, Pu Yu-Mei, Zhang Kai, Pu Jin, Li Yu-Ming, Peng Wan-Lin, Zhang Jin-Ge, Xia Chun-Chao, Li Zhen-Lin
Department of Radiology,West China Hospital,Sichuan University,Chengdu 610041,China.
Sichuan Da Xue Xue Bao Yi Xue Ban. 2018 Mar;49(2):239-242.
To investigate the feasibility of low concentration contrast agent combined double low dose in CT pulmonary angiography.
60 patients with clinically suspected pulmonary embolism examed by CT pulmonary angiography (CTPA) were divided into two groups (experimental group: =30,80 kV, 15 mL,320 mg I/mL;control group: =30,120 kV,50 mL,370 mg I/mL). The average CT value of main right and left pulmonary arteries,lobar arteries was calculated. Imaging post processing techniques included curved plannar reconstruction (CPR),volume rendering (VR) and maximal intensity projection (MIP). The artifact of the remaining contract in the superior vena cava and overall quality of the image were observed and analyzed by two senior doctors who were double blinded.
All patients in two groups completed CTPA successfully. The image qualities of two groupssatisfy clinical diagnostic requirements and no difference of the image qualities was observed between two groups (>0.05). The evaluation of venous pollution in experimental group was better than that of control group (<0.01).No difference of CT values were observed between two groups experimental group (423.2±89.4) HU,control group (465.7±85.6) HU. The SNR and CNR in experimental group were lower than those in control group (<0.01 both).The CT dose index volume (CTDIvol),dose-length product (DLP) and size-specific dose estimates (SSDE) in experimental group were significantly lower than those incontrol group (<0.01 all).
The low concentration contrast agent combined double low dose in CT pulmonary angiography satisfies clinical diagnostic requirements. It has good clinical value for it could reduce venous pollution,iodine contrast agent and radiation exposure.
探讨低浓度对比剂联合双低剂量在CT肺动脉造影中的可行性。
将60例临床怀疑肺栓塞并接受CT肺动脉造影（CTPA）检查的患者分为两组（试验组：n = 30，80 kV，15 mL，320 mg I/mL；对照组：n = 30，120 kV，50 mL，370 mg I/mL）。计算左右主肺动脉、叶动脉的平均CT值。影像后处理技术包括曲面多平面重组（CPR）、容积再现（VR）和最大密度投影（MIP）。由两名资深医生进行双盲观察和分析上腔静脉内残留对比剂伪影及图像整体质量。
两组患者均成功完成CTPA检查。两组图像质量均满足临床诊断要求，两组间图像质量差异无统计学意义（P>0.05）。试验组静脉污染评价优于对照组（P<0.01）。两组CT值差异无统计学意义[试验组（423.2±89.4）HU，对照组（465.7±85.6）HU]（P>0.05）。试验组的信噪比（SNR）和对比噪声比（CNR）均低于对照组（均P<0.01）。试验组的CT剂量指数容积（CTDIvol）、剂量长度乘积（DLP）和大小特异性剂量估计值（SSDE）均显著低于对照组（均P<0.01）。
低浓度对比剂联合双低剂量在CT肺动脉造影中满足临床诊断要求。其可减少静脉污染、碘对比剂用量及辐射剂量，具有良好的临床应用价值。
