CT值预测经皮肾镜EMS碎石清石系统的取石效率*

Clinical value of CT for predicting the stone removal rate after PCNL assisted by EMS LithoClast master*

摘要:

目的   探讨CT值在预测经皮肾镜EMS碎石清石系统取石效率中的应用价值。方法   收集该院2013年8月-2015年7月采用俯卧位标准通道经皮肾镜取石术（PCNL）治疗肾结石患者210例，术前CT扫描测定结石CT值。手术采用22Fr或24Fr通道、18Fr新型标准肾镜，以第四代EMS气压弹道联合超声碎石清石系统碎石取石，计算取石速度（ml/h）。术毕根据超声碎石难易程度及取石速度将210例患者分为A（难碎，取石慢）、B（中等）和C（易碎，取石快）3组，将3组结石的平均CT值分别进行比较，做统计学分析。结果   210例手术均顺利，取石速度18～85 ml/h，将取石速度<30 ml/h者分为A组，30～50 ml/h分为B组，>50 ml/h分为C组。A组共62例（29.5%），B组98例（46.7%），C组50例（23.8%）。3组结石平均CT值分别为（1 108.0±105.0）、（853.0±95.0）和（669.0±77.0）HU，各组间比较差异有统计学意义（P <0.01）。结论   术前测定肾结石CT值对于经皮肾镜EMS碎石清石系统取石效率具有预测价值，CT值>1 100.0 HU者超声碎石清石效果欠佳，可考虑首选其他碎石工具。

Abstract:

Objective To investigate the clinical value of CT in predicting effectiveness of percutaneous nephrolithotomy (PCNL) assisted by EMS LithoClast master. Methods This study was conducted on 210 patients from August 2013 to July 2015. All the patients were undergoing standard PCNL in the prone position assisted by EMS LithoClast master (EMS-Ⅳ). The prone position is the conventional method for performing PCNL. All had a preoperative CT-value to determine the stone's characteristics. The data were analyzed by SPSS using independent-samples t-test and the chi-squared test. All patients were divided into three groups according to the difficulty and rate of gravel. From August 2013 to July 2015, 210 patients were prospectively enrolled and divided into group A (hard), group B (moderate) and group C (easy) according to difficulty and rate of ultrasonic lithotripsy. All the patients were performed standard PCNL (22Fr or 24Fr percutaneous access, 18Fr nephroscope) in the prone position assisted by EMS LithoClast master (EMS-Ⅳ). The stone removal rate was then calculated (ml/h). And average CT values were compared among the three groups. Results 210 cases of surgery all goes well, the stone removal rate was 18～85 ml/h. The stone-free rate <30 ml/h was divided into group A, 30 ～ 50 ml/h were divided into group B, > 50 ml/h divided into group C. Group A [n = 62; CT value = (1 108.0 ± 105.0) HU], group B [(n = 98; CT value = (853.0 ± 95.0) HU], group C [n = 50; CT value = (669.0 ± 77.0) HU]. Significant differences were found (P < 0.01). Conclusion Current evidence suggests that preoperative CT value has a predictive value for determination of kidney stones treated with PCNL. However, when CT value > 1100.0 HU, ultrasonic lithotripsy is not suitable, other treatment should be considered.