Stone recurrence after shockwave lithotripsy: possible enhanced crystal deposition in traumatized tissue in rabbit model.

ABSTRACT

To evaluate the possible traumatizing effect of high-energy shockwaves (HESW) on new stone formation as indicated by crystal deposition in the renal parenchyma, we performed an experimental study in 50 rabbits. During severe oxaluria induced by continuous ethylene glycol (0.75%) administration, animals in the first group (N = 15) received 500 to 1500 shockwaves. Animals in the second group (N = 15) underwent no specific therapy apart from ethylene glycol administration. In a third group of animals (N = 15), only shockwave administration was applied. Sham group animals constituted the last group in our study (N = 5). Three months after shockwave application, tissue sections obtained from treated and untreated kidneys were evaluated histopathologically under light and transmission electron microscopy (TEM) for the presence and degree of crystal deposition in the cortical parenchymal region subjected to HESW. Crystal deposition was evident in the intercellular region and intratubular parts of the parenchyma in animals subjected to HESW application, especially in those receiving relatively high (1000 or 1500) numbers of shockwaves. On the other hand, no crystal formation and deposition was detectable in animals undergoing only ethylene glycol therapy or shockwave administration alone. Sham group animals demonstrated no significant renal histopathology. The traumatic effects of HESW should be evaluated as a factor in new stone formation after SWL.