Consequences of lithotripter shockwave interaction with gas body contrast agent in mouse intestine

Purpose: Shockwave lithotripsy can involve complications associated with he morrhage and internal bleeding which appear to be due to acoustic cavitatio n. Gas-body-based contrast agents recently developed for diagnostic ultraso und can enhance cavitational bioeffects under some conditions. This study e xamined the occurrence and progression of vascular damage in mouse intestin e when a contrast agent was present during shockwave treatment. Materials and Methods: Anesthetized hairless mice were injected with Albune x(R) contrast agent or a gas-body-free blank, and exposed to sham, 200 or 8 00 lithotripter shockwaves. Results: Exposure of the mouse abdomen to lithotripter shockwaves produced petechiae in the intestinal wall and hemorrhage into the lumen. Contrast-ag ent gas bodies greatly enhanced the numbers of petechiae (but not the hemor rhages), relative to the blank agent. When evaluation of these effects was delayed for one day, both effects decreased, and the gas-body-associated pe techiae seemed to disappear. However, survival significantly decreased for mice with added gas bodies and shockwave treatment. Conclusions: The presence of a gas-body-based ultrasound contrast agent enh ances vascular side effects of shockwave lithotripsy. Although there are gr eat uncertainties in relating these observations to human clinical conditio ns, a delay in planned treatment might be prudent for patients scheduled fo r shockwave lithotripsy soon after receiving gas-body-based ultrasound cont rast agents.