Zhou Yufeng, Cocks Franklin H, Preminger Glenn M, Zhong Pei
Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708-0300, USA.
J Urol. 2004 Nov;172(5 Pt 1):1892-8. doi: 10.1097/01.ju.0000142827.41910.a2.
We developed innovations in shock wave lithotripsy (SWL) technology.
Two technical upgrades were implemented in an original unmodified HM-3 lithotriptor (Dornier Medical Systems, Inc., Kennesaw, Georgia). First, a single unit ellipsoidal reflector insert was used to modify the profile of lithotriptor shock wave (LSW) to decrease the propensity of tissue injury in SWL. Second, a piezoelectric annular array (PEAA) generator (f = 230 kHz and F = 150 mm) was used to produce an auxiliary shock wave of approximately 13 MPa in peak pressure (at 4 kV output voltage) to intensify the collapse of LSW induced bubbles near the target stone for improved comminution efficiency.
Consistent rupture of a vessel phantom made of single cellulose hollow fiber (i.d. = 0.2 mm) was produced after 30 shocks by the original HM-3 reflector at 20 kV. In comparison no vessel rupture could be produced after 200 shocks using the upgraded reflector at 22 kV or the PEAA generator at 4 kV. Using cylindrical BegoStone phantoms (Bego USA, Smithfield, Rhode Island) stone comminution efficiencies (mean +/- sd) after 1,500 shocks produced by the original and upgraded HM-3 reflectors, and the combined PEAA/upgraded HM-3 system, were 81.3% +/- 3.5%, 90.1% +/- 4.3% and 95.2% +/- 3.3%, respectively (p<0.05).
Optimization of the pulse profile and sequence of LSW can significantly improve stone comminution while simultaneously decreasing the propensity of tissue injury during in vitro SWL. This novel concept and associated technologies may be used to upgrade other existing lithotriptors and to design new shock wave lithotriptors for improved performance and safety.
我们在冲击波碎石术（SWL）技术方面进行了创新。
在一台未改装的原装HM - 3碎石机（多尼尔医疗系统公司，佐治亚州肯尼索）上实施了两项技术升级。首先，使用单个单元的椭圆形反射器插件来改变碎石机冲击波（LSW）的波形，以降低SWL中组织损伤的倾向。其次，使用压电环形阵列（PEAA）发生器（频率f = 230 kHz，焦点F = 150 mm）产生峰值压力约为13 MPa的辅助冲击波（在4 kV输出电压时），以增强目标结石附近LSW诱导气泡的塌陷，从而提高粉碎效率。
原装HM - 3反射器在20 kV下进行30次冲击后，由单根纤维素中空纤维（内径 = 0.2 mm）制成的血管模型会持续破裂。相比之下，使用升级后的反射器在22 kV下或PEAA发生器在4 kV下进行200次冲击后，血管模型均未破裂。使用圆柱形BegoStone模型（美国贝格公司，罗德岛州史密斯菲尔德），原装和升级后的HM - 3反射器以及PEAA/升级后的HM - 3组合系统在进行1500次冲击后的结石粉碎效率（平均值±标准差）分别为81.3%±3.5%、90.1%±4.3%和95.2%±（此处原文有误，应是3.3%），差异有统计学意义（p<0.05）。
优化LSW的脉冲波形和序列可显著提高结石粉碎效果，同时降低体外SWL过程中组织损伤倾向。这一新颖概念及相关技术可用于升级其他现有碎石机，并设计新型冲击波碎石机，以提高性能和安全性。
