Dretler S P
Harvard Medical School, Boston.
Arch Esp Urol. 1993 Jun;46(5):439-43.
The Electromechanical Impactor was conceived as a safe and effective device for intracorporeal stone fragmentation. It is a 3 French EHL electrode enclosed within a stainless steel sheath. The interior is irrigated with saline. Discharge of the system causes an EHL spark which vaporizes saline and produces a cavitation bubble and subsequent shock wave. The shock wave propels a conical titanium tip forward for a distance of 2.7 mm with an impact pressure of 900 bar. Bench and animal testing has proven its effectiveness for stone fragmentation and safety for use within the ureter. The mean lifetime of each probe is approximately 700 pulses. It is used under direct vision through the straight operating port of a rigid or semi-rigid 9.5 French ureteroscope. Clinical studies at the Massachusetts General Hospital (reported herein) and the Mayo Clinic demonstrate approximately 90% efficacy. It is especially effective on cystine, calcium oxalate dihydrate, struvite and mixed calcium oxalate monohydrate calculi. Shiny-smooth black calcium oxalate monohydrate calculi will fragment but are more resistant. There has been no evidence of ureteral wall injury. The EMI is currently 5 French and is used both safely and effectively under direct vision of fragment ureteral calculi. Larger sizes are designed for percutaneous use and for bladder stone fragmentation.
电动冲击器被设计为一种用于体内结石破碎的安全有效的设备。它是一个3法式的电液压碎石电极，封装在不锈钢护套内。内部用盐水冲洗。系统放电会产生电液压火花，使盐水汽化并产生空化气泡及随后的冲击波。冲击波将一个圆锥形钛质尖端向前推进2.7毫米的距离，冲击压力为900巴。台架试验和动物试验已证明其在结石破碎方面的有效性以及在输尿管内使用的安全性。每个探头的平均寿命约为700次脉冲。它通过刚性或半刚性9.5法式输尿管镜的直操作端口在直视下使用。麻省总医院（本文报道）和梅奥诊所的临床研究表明其有效性约为90%。它对胱氨酸结石、二水草酸钙结石、磷酸镁铵结石和一水合草酸钙混合结石特别有效。光滑发亮的黑色一水合草酸钙结石会破碎，但更具抗性。没有输尿管壁损伤的证据。目前的电动冲击器为5法式，在直视下用于破碎输尿管结石既安全又有效。更大尺寸的设计用于经皮使用和膀胱结石破碎。
