多层螺旋CT重建卷积函数在肋骨骨折中的应用研究

目的探讨多层螺旋CT(MSCT)不同重建卷积函数对肋骨图像质量及诊断肋骨骨折准确性的影响。方法连续选取30例确诊肋骨骨折患者的CT原始数据,在工作站依次应用B10、B20、B30、B40、B50、B60、B70、B80、B90九个卷积函数重建,分别在9组图像的同一层面测定肋骨及邻近肌肉区CT值及噪声,并计算信噪比(SNR)及对比噪声比(CNR),同时对9组图像进行图像质量评分并记录肋骨骨折的类型及数目,而后进行对比分析。结果 (1)随着B值的增加,9组图像的噪声呈线性上升,SNR、CNR呈下降趋势;(2)B70重建图像的图像质量评分是4.83±0.28,与其他B值比较图像质量评分差异有统计学意义(F=29.07,P=0.000);(3)B50^B70重建图像的肋骨骨折检出率为98.07%,与其他B值比较差异有统计学意义(P值分别为0.008、0.031、0.008)。结论 B70卷积函数重建图像质量优于其他函数重建,可以提高肋骨骨折的诊断准确性。

Application value of MSCT images with different reconstruction kernels in diagnosis of rib fracture

ObjectiveTo explore the influence of MSCT images with different reconstruction kernels on image quality and diagnostic accuracy of rib fracture.MethodsThe raw data of 30 cases with confirmed rib fractures were reconstructed into nine groups with various kernels （B10, B20, B30, B40, B50, B60, B70, B80, B90）. The image noise and CT value were measured on the same level of different reconstructed images, then the SNR and CNR were calculated. At the same time, the image quality score and the type, number of rib fracture were recorded.Results （1） With the increased of kernels, the noise of rib images showed linear rise, the SNR and CNR of rib images had declined. （2） The rib image quality score of B70 reconstructed images was 4.83±0.28, there was significant difference in image quality score in comparison with other kernels （F=29.07,P=0.000）. （3） The accurate rate of diagnosis of rib fracture was 98.07% on B50-B70 reconstructed images, there was significant difference in accuracy of diagnosis in rib fractures （P=0.008, 0.031, 0.008）.Conclusion The image quality of B70 reconstructed images was better than other kernels and can improve the accuracy of diagnosis in rib fracture.