双源CT低剂量Flash扫描双期脑血管减影成像的可行性  

Feasibility of low dose Flash spiral scan mode of dual-source CT in cerebral double phase subtraction angiography

作　　者：毛俊 

机构地区：[1]暨南大学附属珠海医院珠海市人民医院放射科,广东珠海519000

出　　处：《实用放射学杂志》2015年第4期655-658,共4页Journal of Practical Radiology

摘　　要：目的：通过对比双能量减影,探讨第2代双源 CT 低剂量 Flash 扫描双期脑血管减影成像评价脑血管的可行性。方法回顾性分析60例双期脑血管 CT 检查,分成 A 组(30例)：Flash 扫描；B 组(30例)：双能量扫描。计算2组图像信噪比(SNR)与对比噪声比(CNR)及辐射剂量,按去骨程度及血管显示与切割程度,采取双盲法分别对减影图像评分(1~5分)。用 t 检验及 Mann-Whitney 检验比较2组间差异。结果2组动、静脉期 SNR 差异均不显著(P >0.05)。A 组动、静脉期 CNR(40.89±8.89,40.27±9.90)均高于 B 组(35.28±8.43,34.89±8.66),差异有统计学意义(P <0.05)。2组动、静脉期图像去骨评分及静脉期血管评分差异均无统计学意义(P >0.05),A 组动脉期血管评分(4.93±0.25)高于 B 组(3.87±0.97),差异显著(P <0.05),B 组部分颈内动脉管腔见切割。A 组平均总剂量长度乘积(DLP)[(226±5.69)mGy/cm]较 B 组[(368±21.35)mGy/cm]降低约39%(P <0.05)。结论低剂量 Flash 扫描双期脑血管减影图像质量与双能量减影相似,且动脉期颈内动脉图像更佳及辐射剂量明显降低,可推荐为临床脑血管检查应用。Objective To assess the feasibility of double phase subtraction angiography with second generation (128-slice )dual-source CT in low dose Flash spiral scan mode for the evaluation of cerebral vessel,compared with dual-energy subtraction angiogra-phy.Methods 60 patients underwent double phrase CT angiography were divided into group A (n = 30,with Flash spiral scan mode),group B(n=30,with dual-energy scan mode).The signal-to-noise ratio(SNR),the contrast-to-noise ratio(CNR)and the av-erage radiation of double phrase subtraction images were measured in two groups,respectively.The double phase subtraction images quality were graded by 2 independent readers on a 5-point scale(5=excellent)in double-blind,according to various degrees of the re-sidual bones,the vessel displayed and luminal integrity,respectively.Differences between two groups were analyzed by Mann-whit-ney test and t test.Results The double phrase image SNR showed no difference to both two groups(P >0.05).The image CNR of arterial and venous phase in group A were higher than that of group B(40.89±8.89 and 40.27 ±9.90 in group A vs 35.28 ±8.43 and 34.89±8.66 in group B;P <0.05)respectively.There were no singnificant difference in the bone removal image scores of doub-le phase and in the vessel image scores of venous phase to both two groups respectively(P >0.05).The vessel image scores of arterial phase were higher in group A than that of group B(4.93±0.25 vs 3.87±0.97;P <0.05).Some internal carotid in the base of skull has not good luminal integrity in group B.The mean dose length product (DLP)in group A was lower than that of group B,with a 39 percent reduction[(226±5.69 )mGy/cm vs (368 ± 21.35 )mGy/cm,P < 0.05 ].Conclusion With the roughly similar image quality to dual-energy double phase subtraction angiography,the cerebral vessels can be assessed using dual-source CT subtraction angiography in Flash spiral scan mode and a lower radiation dose.

关 键 词：脑血管造影术 计算机体层成像 

分 类 号：R322.81[医药卫生—人体解剖和组织胚胎学] R814.43[医药卫生—基础医学]