320排CT分次团注结合自动管电流技术在低剂量CT尿路造影中的应用

Application of 320-slice CT split bolus combined with automatic tube current technique in CTU with low dose

目的:探讨320排CT分次团注结合自动管电流技术在低剂量CT尿路造影(CTU)中的应用。方法:选取医院收治的89例具有泌尿系统临床症状的患者,按照随机数表法将其分为观察组(45例)和对照组(44例),观察组给予CT分次团注双期扫描,对照组予以CT单次团注4期扫描,两组均采用自动管电流技术,对比两组CT客观图像质量的信噪比(SNR)和对比噪声比(CNR),分析其主观图像质量的伪影、噪声、结构及清晰度;对比分析两组辐射剂量中CT剂量指数(CTDI)、CT剂量长度乘积(DLP)和有效辐射剂量(ED)。结果:观察组SNR和CNR与对照组比较差异无统计学意义;观察组图像伪影、噪声、结构及清晰度与对照组比较差异无统计学意义;观察组CTDI、DLP及ED均低于对照组,差异有统计学意义(t=13.395,t=14.986,t=14.750;P<0.05)。结论:CT分次团注结合自动管电流技术可减少CTU辐射剂量,且并未对图像质量造成显著影响。

Objective:To investigate the application of 320-slice computed tomography(CT)split bolus combined with automatic tube current technique in CT urography(CTU)with low-dose.Methods:89 patients with clinical symptoms of urinary system who admitted to hospital were selected as subjects.And they were divided into observation group(n=45)and control group(n=44)according to the random number table method.The observation group underwent double-phase split-bolus CT scan while the control group underwent single-bolus four-phase CT scan.Both groups used automatic tube current technique.The signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of CT objective image quality of two groups were compared,and the artifact,noise,structure and clarity of subjective image quality were analyzed.And CT dose index(CTDI),CT dose-length product(DLP)and radiation effective dose(ED)of radiation doses were further compared and analyzed.Results:There were no significant differences in SNR and CNR between the two groups.And there were no significant differences in artifacts,noise,structure and clarity between the two groups.And the results of CTDI,DLP and ED of observation group were significantly lower than those of control group(t=13.395,t=14.986,t=14.750,P<0.05).Conclusion:The combined method of CT split bolus and automatic tube current technique can reduce radiation dose of CTU,and it doesn’t produce significant effects on image quality.