杨尚文,邵明冉,杨献峰,等.“三低”技术联合全模型迭代重建算法在头颈部CT血管成像中的可行性研究[J].中华放射医学与防护杂志,2017,37(1):62-67.Yang Shangwen,Shao Mingran,Yang Xianfeng,et al.A feasibility study on “Tri-Low” technology in combination with iterative model reconstruction(IMR) algorithm in CT angiography(CTA) of the head-and-neck vessels[J].Chin J Radiol Med Prot,2017,37(1):62-67 |
“三低”技术联合全模型迭代重建算法在头颈部CT血管成像中的可行性研究 |
A feasibility study on “Tri-Low” technology in combination with iterative model reconstruction(IMR) algorithm in CT angiography(CTA) of the head-and-neck vessels |
投稿时间:2016-08-04 |
DOI:10.3760/cma.j.issn.0254-5098.2017.01.012 |
中文关键词: 血管成像 体层摄影术,X射线计算机 辐射剂量 迭代重建 |
英文关键词:Angiography Tomography, X-ray computed Radiation dose Iterative reconstruction |
基金项目:江苏省卫生厅青年科研课题(Q201410) |
|
摘要点击次数: 4657 |
全文下载次数: 2501 |
中文摘要: |
目的探讨80 kV低管电压、低对比剂注射速率和低对比剂用量的“三低”技术,联合全模型迭代重建(IMR)算法在头颈部CT血管成像(CTA)检查的可行性。方法前瞻性连续收集2015年7-11月行头颈部CTA检查的患者60例,采用随机数字表法将其分为A、B两组,每组各30例。A组为常规剂量组,管电压120 kV,滤过反投影(FBP)重建,对比剂注射速率4.5~5.5 ml/s,注射时间10 s;B组为80 kV低管电压组,分别使用FBP和IMR进行图像重建,得到B1和B2两组图像,对比剂注射速率3.5~4.0 ml/s,注射时间10 s。测量并计算A组、B1组、B2组的图像动脉血管CT值、图像噪声、信噪比(SNR)和对比噪声比(CNR),并由2名放射诊断医师对图像质量按照5分法进行评价。3组图像间动脉血管CT值、图像噪声、SNR和CNR采用单因素方差分析,图像质量主观评价采用Kruskal-Wallis检验,两组检查的容积CT剂量指数(CTDIvol)和剂量长度乘积(DLP)比较采用两个独立样本t检验。结果 A、B1和B2组3组图像质量主观评分范围分别为3~5分、2~4分和3~5分,B1组有12例患者图像之间评分≤2分,图像无法诊断。A和B1、A和B2、B1和B2图像之间评分差异均有统计学意义(t=4.55、-6.58、-2.03,P<0.05)。B2组与A组的图像客观指标SNR和CNR比较差异无统计学意义(P>0.05),但B2和A组图像的SNR、CNR均优于B1组,差异均有统计学意义(t=-12.14、13.39、-9.96、9.45,P<0.05)。B组CTDIvol[(1.7±0.2)mGy]比A组[(8.9±1.0)mGy]减少了80.9%,DLP[(77.9±9.0)mGy·cm]比A组[(415.5±56.7)mGy·cm]减少了81.3%,B组对比剂注射速率[(3.9±0.1)ml/s]比A组[(5.0±0.2)ml/s]减少了22.0%,B组对比剂总量[(39.2±1.9)ml]比A组[(50.3±2.2)ml]减少22.1%,差异有统计学意义(t=39.1、32.2、20.8、20.8,P<0.05)。结论使用80 kV管电压、低对比剂注射速率和用量,并使用IMR算法进行图像重建,进行头颈部CTA扫描是可行的。可以在保证图像质量的基础上,使患者辐射剂量减少81.3%。临床试验注册号中国临床试验注册中心,ChiCTR-BOC-16010060。 |
英文摘要: |
Objective To evaluate the feasibility of low-tube-voltage,low injection rate,low contrast agent dosage in combination with iterative model reconstruction(IMR) algorithm in CT angiography(CTA) of the head-and-neck vessels.Methods Sixty patients who underwent CT angiography of the head-and-neck vessels were randomly divided into groups A and B with 30 cases in each group. Patients in group A received a conventional scan with 120 kVp and filterback projected(FBP) reconstruction. Patients in group B received a low-dose scan with 80 kVp, and image reconstruction with FBP(group B1) and IMR(group B2) algorithm. The contrast agent protocol were as follows:the injection time in all patients was 10s, the injection rate was 4.5-5.5 ml/s in group A while 3.5-4.0 ml/s in group B. The CT values of artery, image noise, signal to noise ratio(SNR) and contrast to noise ratio(CNR) were measured and compared among three groups with One-way ANOVA analysis. Image quality was evaluated by two radiologists with five scale method, and compared with Kruskal-Wallis test. The CT dose index volume (CTDIvol) and dose length product (DLP) were recorded and compared between groups with two independent samples t-test. Results The image quality scores of groups A, B1and B2 were 3-5, 2-4 and 3-5, respectively.Image quality of twelve patients in group B1 couldn't meet the diagnostic requirements but none in group A and B2.The objective image parameters SNR and CNR for group B2 were equal to group A(P>0.05), while those for group B1 were lower than group A(t=13.39, 9.45,P<0.05) and group B2(t=-12.14, -9.96, P<0.05). CTDIvol and DLP for group B were separately 80.9%, 81.3% lower than those of group A(t=39.1, 32.2, P<0.05). The injection rate and contrast agent volume for group B were separately 22.0%, 22.1% lower than those of group A(t=20.8, 20.8, P<0.01).Conclusions It is feasible in CT angiography of the head-and-neck vessels with lower tube-voltage, lower injection rate, lower contrast agent dose and combining with iterative model reconstruction algorithm. This protocol can reduce the radiation dose by 81.3% while maintaining image quality.Trial registration Chinese clinical trial registry,ChiCTR-BOC-16010060. |
HTML 查看全文 查看/发表评论 下载PDF阅读器 |
关闭 |
|
|
|