数字X射线摄影中散射线滤除模板成像质量与辐射剂量学评价

Scatter titration method in digital radiography： The inlaging quality and irradiation dose evaluation for scatter filtering template performance

目的比较散射线滤除模板及常规滤线栅对数字X射线影像进行散射线校正所成影像质量与辐射剂量差异。方法以对比度-细节体模（CDRAD2．0）及ROC统计学体模（ALVIMTRS）为成像对象，分别使用散射线滤除模板技术和常规滤线栅技术，获取经散射线校正的体模数字X射线影像，比较两种散射线滤除方法所得的体模影像图像质量因子（IQF）和信号检出概率，分析两种方法图像质量及体模表面入射剂量差别。结果在不同体模表面照射剂量条件下，应用散射线滤除模板技术和常规滤线栅技术，消除散射线后的数字影像其图像质量因子（IQF）和信号检出概率（Pdet）差异均有统计学意义（P〈0．05）。结论数字X射线摄影时，应用散射线滤除模板技术（sFrr）可以有效滤除散射线。与滤线栅相比，相同照射条件下SFTF能够明显改善图像质量；在获得相同图像质量前提下，应用SFTT，体模表面入射剂量比使用滤线栅降低30％；SFTT为数字X射线摄影中有效滤除散射线、提高X射线图像质量、降低患者剂量的可选择方法。

Objective The imaging quality and irradiation dose were compared between scatter filtering template performance and conventional grid in digital radiography. Methods Images of contrast-detail phantom and ROC statistic phantom corrected with scatter filtering template method and grid were obtained, respectively. The image quality factors （IQF） and signal detection probability values （Pdet） and imaging dose were analyzed by ANOVA, SNK and t test statistics for the two methods of scatter removing. Results The difference of IQF and signal detection probability of images corrected by scatter filtering template technique and conventional grid was statistically significant. Conclusions In digital radiography, STFF can effectively filter scattering, improve image quality without increasing the exposure. With the same image quality, it can reduce the entrance surface dose by about 30% than filter grid. In order to effectively filter scattering, improve the quality of X-ray image, and reduce the patient dose, STFF is an alternative method.