螺旋CT三维重建技术在鹿角形肾结石经皮肾镜取石术中的应用价值

Assistance of three-dimensional reconstruction of spiral CT for staghorn calculi in percutaneous nephroithotomy

目的评价螺旋CT三维重建技术在经皮肾镜取石术（PCNL）治疗鹿角形肾结石中的应用价值。方法鹿角形肾结石87例104侧。采用16排螺旋CT平扫，容积成像技术进行结石三维重建，根据重建结果设定穿刺目标肾盏，初步判断建立多通道的必要性，并计算结石体积。患者均接受B超引导下24FPCNL，记录穿刺通道位置、数目以及其他手术技术参数，收集结石并测量结石体积，KUB判断有无结石残留。结果术中实际穿刺肾盏与术前根据CT三维重建结果设计的目标肾盏选择完全一致，建立多通道数目与术前预测符合率为91．5％（43／47）；一期手术结百取净率87．5％，二期或多期手术后取净率91．7％；清除结石体积平均（16．34±13．79）cm3，术前CT三维重建估算结石体积平均为（19．35±19．24）cm3，两者之间相关性分析r=0．993，P=0．000。结论螺旋CT三维重建技术可形象直观地显示鹿角形肾结石的立体结构，指导术前穿刺通道的选择，并可以准确计量结石体积。

Objective To assess the assistance role of three-dimensional reconstruction of staghorn calculi by 16-slice spiral CT to percutaneous nephrolithotomy （PCNL）. Methods A total of 87 patients with 104 staghorn stones underwent 24 F-tract PCNL. 16-slice spiral CT scan and three-dimensional （3D） reconstruction by volume rendering technique were carried out before PCNL for tract placement planning, the necessity for multiple tracts and stone burden. Tract placement, tract num- ber, operation time, bleeding requiring transfusion and volume of stone cleared were recorded. KUB was taken to explore residual calculi after operation and thus stone free rate was noted. Results In- traoperative tract placement was according to preoperative planning with 3D reconstruction of calculi. Forty-three calculi were cleared by multiple accesses, while multiple accesses were supposed necessary for 47 caculi. The stone free rate of one-session operation was 87.5%, and the last stone free rate after second-look procedure was 91.7%. The stone burden of 3D reconstruction of CT （19.35 ±19.24 cm3） was significantly correlated with the mean volume of cleared calculi （16.34± 13.79 cm3） in operation （r：0. 993, P=0. 000 ）. Conclusion The 3D reconstruction of spiral CT for staghorn calculi could show the precise construction of calculi, which could help to plan tract placement, evaluate the necessity of multiple tracts and stone burden.