Department of Radiology, Mayo Clinic, Rochester, Minnesota 55905, USA.
J Urol. 2013 Jun;189(6):2350-6. doi: 10.1016/j.juro.2012.11.004. Epub 2012 Nov 7.
We differentiated calcium oxalate monohydrate and calcium oxalate dihydrate kidney stones using micro and clinical computerized tomography images.
A total of 22 calcium oxalate monohydrate and 15 calcium oxalate dihydrate human kidney stones were scanned using a commercial micro-computerized tomography scanner with a pixel size of 7 to 23 μm. Under an institutional review board approved protocol, image data on 10 calcium oxalate monohydrate and 9 calcium oxalate dihydrate stones greater than 5 mm were retrieved from a total of 80 patients who underwent clinical dual energy computerized tomography for clinical indications and had stones available for infrared spectroscopic compositional analysis. Micro and clinical computerized tomography images were processed using in-house software, which quantified stone surface morphology with curvature based calculations. A shape index was generated as a quantitative shape metric to differentiate calcium oxalate monohydrate from calcium oxalate dihydrate stones. Statistical tests were used to test the performance of the shape index.
On micro-computerized tomography images the shape index of calcium oxalate monohydrate and calcium oxalate dihydrate stones significantly differed (ROC curve AUC 0.92, p <0.0001). At the optimal cutoff sensitivity was 0.93 and specificity was 0.91. On clinical computerized tomography images a significant morphological difference was also detected (p = 0.007). AUC, sensitivity and specificity were 0.90, 1 and 0.73, respectively.
On micro and clinical computerized tomography images a morphological difference was detectable in calcium oxalate monohydrate and calcium oxalate dihydrate stones larger than 5 mm. The shape index is a highly promising method that can distinguish calcium oxalate monohydrate and calcium oxalate dihydrate stones with reasonable accuracy.
我们使用微计算机断层扫描和临床计算机断层扫描图像对一水合草酸钙和二水草酸钙肾结石进行了区分。
使用商业微计算机断层扫描系统对 22 个一水合草酸钙和 15 个二水草酸钙的人类肾结石进行扫描，像素大小为 7 至 23μm。在机构审查委员会批准的方案下，从总共 80 名因临床指征接受临床双能计算机断层扫描并可获得用于红外光谱成分分析的结石的患者中，检索了 10 个大于 5mm 的一水合草酸钙和 9 个二水草酸钙结石的微计算机断层扫描和临床计算机断层扫描图像数据。使用内部软件处理微计算机断层扫描和临床计算机断层扫描图像，使用基于曲率的计算量化结石表面形态。生成形状指数作为区分一水合草酸钙和二水草酸钙结石的定量形状度量。使用统计检验来检验形状指数的性能。
在微计算机断层扫描图像上，一水合草酸钙和二水草酸钙结石的形状指数有显著差异（ROC 曲线 AUC 0.92，p <0.0001）。在最佳截断值下，敏感性为 0.93，特异性为 0.91。在临床计算机断层扫描图像上也检测到了显著的形态差异（p = 0.007）。AUC、敏感性和特异性分别为 0.90、1 和 0.73。
在微计算机断层扫描和临床计算机断层扫描图像上，大于 5mm 的一水合草酸钙和二水草酸钙结石可检测到形态差异。形状指数是一种很有前途的方法，可以合理准确地区分一水合草酸钙和二水草酸钙结石。
