小剂量对比剂CTU在经皮肾镜碎石取石术中的应用研究

目的 探讨小剂量对比剂联合呋塞米注射液和生理盐水CTU新技术对经皮肾镜碎石取石术（PCNL）术前穿刺通道选择的临床应用价值。方法 采用改良的小剂量对比剂CTU检查方案对23例复杂性肾结石患者行小剂量对比剂联合呋塞米注射液和生理盐水CTU检查。在分泌期扫描前进行常规平扫。采用ROI法对23例患者肾结石密度进行测量，以了解复杂性肾结石的密度分布特点；采用ROI法对23例患者分泌期肾实质上极、中部、下极及上组肾盏、中组肾盏、下组肾盏、肾盂CT值进行测量并对测量结果比较，以了解小剂量对比剂CTU肾实质及肾盂肾盏系统内对比剂分泌均匀性；对23例患者复杂性肾结石及PC系统进行分泌期轴位、冠状位MIP及VR重组并对重组图像进行评分，以了解哪种重组方法对肾结石、PC系统显示最佳。结果 23例患者复杂性肾结石密度中位数为1182.41HU，95% CI：548.26~1734.54HU；小剂量对比剂CTU肾实质对比剂分泌均匀；PC系统内对比剂分泌均匀且明显低于复杂性肾结石密度使得复杂性肾结石和PC系统重组的准确性分别达到82.6%和87%；3种重组方案中，冠状位MIP用于描述复杂性肾结石的评分最高。冠状位MIP用于显示肾盂肾盏解剖结构的评分最高。结论 小剂量对比剂CTU三维重组图像可直观显示复杂性结石的空间位置、PC系统的截面与立体解剖结构及其与周围组织的关系，有助于PCNL术前穿刺通道选择。

Small Dose Contrast Medium CTU for Percutaneous Nephrostolithotomy:Application Research

Objective To evaluate the application value of small dose contrast medium combined with furosemide injection and saline CTU as a new technology for the puncture channel selection of pre-PCNL. Methods Small dose contrast medium CTU combined with furosemide injection and saline examinations was taken in the 23 patients with complex renal calculi by using a modified small dose contrast medium CTU examination protocol. Before excretory phase, a routine non-enhanced scan was taken. In order to find out the characteristics of the density distribution of complex renal calculi, complex renal calculi density of the 23 patients was measured by using ROI. In order to find out excretory uniformity of contrast medium within renal parenchyma and the pelvicalyceal (PC) system with small dose contrast medium CTU in the 23 patients, CT value of upper pole, inter-polar part, lower pole renal parenchyma and upper pole calyx, inter-polar calyx, lower pole calyx, renal pelvis of excretory phase was measured by using ROI and compared. In order to find out which kind of reconstructions (axial MIP, coronal MIP and VR) was the best for renal calculus and PC system depiction, complex renal calculi and PC system of the 23 patients were reconstructed on excretory phase and scored. Results The median and 95% confidence interval (CI) of the complex renal calculi density in the 23 patients were 1182.41HU, 548.26-1734.54HU. Excretory uniformity of contrast medium within renal parenchyma with small dose contrast medium was achieved.As uniform contrast medium in PC system was obviously lower than calculus density,precise rate of calculus and pelvicalyceal reconstructions came up to 82.6% and 87%, respectively.Among the three recombination methods, coronal MIP was rated best for calculus depiction and Coronal MIP best for PC anatomy. Conclusion Three-dimensional reconstruction images of small dose contrast medium CTU can visualize the spatial location of the complex renal calculi, the cross-section and three-dimensional anatomical structure of the PC system and its relationship with the surrounding tissues and they are helpful for the pre-PCNL puncture channel selection.