Abstract (Invited)

Shockwave Lithotripsy (SWL) Induces Significant Structural and Functional Changes in the Kidney

A.P.Evan, B.A.Connors, P.M.Blomgren (Department of Anatomy & Cell Biology, Indiana University, Indianapolis, IN, USA); L.R.Willis (Department of Pharmacology & Toxicology, Indiana University, Indianapolis, IN, USA); J.A.Lingeman (Methodist Hospital Institute for Kidney Stone disease, Indianapolis, IN, USA)

e-mail: evan@anatomy.iupui.edu

Early clinical studies suggested that SWL was free of bioeffects. However, experimental and clinical studies have clearly documented acute and chronic renal changes (Evan et al., Nephron 78:1-8; Janetschek et al., J. Urology 158:346-351). The foundation for understanding the characteristics and consequences of clinical SWL-injury has been well-controlled renal structural and functional studies in pigs, a model that closely mimics the human kidney. Our studies show that 2000 shocks at 24 kV administered by the Dornier HM3 induces a predictable, irreversible vascular injury at F2 that is associated with a transient renal vasocontrictive event in both treated and untreated kidneys. The SWL-induced trauma is associated with inflammation at the site of damage. While lesion size increases with kV level and shockwave number, the pronounced vasoconstriction has a lower threshold for these same parameters. In addition, kidney size and pre-existing renal injury are risk factors for SWL exaggerating the impairment of renal tubular and hemodynamic function observed at a clinical dose. Thus, there is still a concern that SWL may generate a major health risk to stone patients. These issues are of great importance in light of the recent observations suggesting current lithotripters are not improving but may be getting worse.

Section : 5