CT能谱成像对物质内碘含量测定的价值:体模研究

The Value of Gemstone Spectral Imaging in Analysis of the Content of Iodine:Phantom Study

目的:利用CT的能谱成像(gemstone spectral imaging,GSI)技术能够生成新的物质密度图像的能力,评价GSI方法测定物质内碘含量的可信度和准确性。方法:将含碘对比剂溶液用蒸馏水分散成18种不同的浓度,使用GE公司宝石CT(discovery CT750 HD)GSI扫描模式,选择FOV=25cm,层厚=0.625mm,球管旋转速度分别为0.6s/转、0.8s/转、1.0s/转,图像利用GSI Viewer浏览器处理,测量溶液中的碘含量。采用Pear-son相关分析和配对t检验方法进行统计学分析。结果:GSI扫描模式0.6s/转、0.8s/转、1.0s/转三组碘浓度测量值与碘含量真实值之间均具有明显相关性(r均为0.999,P均为0.000);各组测量值与碘含量真实值之间的差异无统计学意义(P均大于0.05)。结论:宝石CT具有能谱成像能力,能准确地反映不同浓度溶液的碘含量,可以用于定量分析。

Purpose： Gemstone spectral imaging（GSI） has the ability to generate material decomposition（MD） images for separating materials and analyzing the content of special materials.The purpose of this study was to evaluate the confidence and accuracy of GSI in analyzing the content of iodine.Methods： Iodine solution with varying iodine concentrations（mg/ml） were dissolved in distilled water into 18 different groups in 50ml tubes.GSI scans were acquired on a Discovery CT750 HD scanner with a small field of view（FOV,25cm） and thin slices（0.625mm）.Tube rotation speed was 0.6s / circle,0.8s / circle and 1.0s/circle respectively.Image processing was performed on GSI Viewer browser to measure the iodine content of the solution.Pearson＇s correlation analysis and paired t test methods were used for statistical analysis.Results：Positive correlation was found between the iodine concentrations and the reference-standard density of iodine（r=0.999,P=0.000 were found in every group）.There was no significant difference between the measurements and the true value of iodine content in every group（P0.05）. Conclusions： GSI mode can generate MD images for analyzing the material contents,GSI mode can accurately reflect the content of iodine in different concentrations and be used for quantitative analysis.