Matlaga Brian R, McAteer James A, Connors Bret A, Handa Rajash K, Evan Andrew P, Williams James C, Lingeman James E, Willis Lynn R
Indiana University School of Medicine, and Methodist Hospital Institute for Kidney Stone Disease, Indianapolis, IN 46202, USA.
J Endourol. 2008 Jan;22(1):121-6. doi: 10.1089/end.2007.9852.
Shockwave lithotripsy (SWL) injures renal tissue, and cavitation has been reported to mediate some of these effects. Much of the work characterizing the cavitation injury of SWL has been performed in small animals or in vitro. We describe experiments that promote cavitation during SWL and estimate the spatial distribution of the resulting hemorrhagic lesion in a large-animal (porcine) model of clinical lithotripsy.
The lower pole calix of the left kidney in female farm pigs was targeted for SWL with a Dornier HM3 lithotripter. Intraventricular injections of polystyrene microspheres were made before and at intervals during lithotripsy to blanket systemic circulation with cavitation nuclei. Following SWL, the abdominal viscera were inspected and the kidneys were processed for morphologic analysis.
Extensive surface hemorrhage occurred over both the targeted and contralateral kidneys, along with widespread petechial hemorrhage over the spleen, intestines, and peritoneum. The targeted kidneys developed subcapsular hematomas. Histology revealed focal and diffuse damage to the targeted kidneys and vascular rupture in both kidneys with complete necrosis of the walls of intralobular arteries and veins.
These results demonstrate the potential for unfocused shockwaves to damage blood vessels outside the focal zone of the lithotripter when the vasculature is seeded with cavitation nuclei. The wide distribution of damage suggests that the acoustic field of a lithotripter delivers negative pressures that exceed the cavitation threshold far off the acoustic axis. The findings underscore that conditions permissive for cavitation can lead to dramatic sequelae during SWL.
冲击波碎石术（SWL）会损伤肾组织，据报道空化作用介导了其中一些效应。许多描述SWL空化损伤的研究是在小动物或体外进行的。我们描述了在临床碎石术的大型动物（猪）模型中促进SWL期间空化作用并估计由此产生的出血性病变空间分布的实验。
使用多尼尔HM3碎石机对雌性农场猪左肾下极肾盏进行SWL治疗。在碎石术前及碎石过程中间隔进行脑室内注射聚苯乙烯微球，以使全身循环充满空化核。SWL治疗后，检查腹部脏器并对肾脏进行形态学分析。
目标肾脏和对侧肾脏均出现广泛的表面出血，同时脾脏、肠道和腹膜出现广泛的瘀点性出血。目标肾脏形成了包膜下血肿。组织学检查显示目标肾脏有局灶性和弥漫性损伤，双侧肾脏血管破裂，小叶内动脉和静脉壁完全坏死。
这些结果表明，当脉管系统中充满空化核时，非聚焦冲击波有可能损伤碎石机焦点区域外的血管。损伤的广泛分布表明，碎石机的声场在远离声轴的地方产生的负压超过了空化阈值。这些发现强调，允许空化的条件会在SWL期间导致严重的后遗症。
