In an effort to mimic the condition of kidneys in many older patients, pyelonephritis, an inflammation of the kidneys, was induced in the kidneys of young pigs. The diseased kidneys were then treated with 2,000 shock waves, which is at the low end of clinical dosage. Dr. Evan said the severity of the changes caused by the shock waves were similar to the changes found in healthy kidneys exposed to much higher numbers of shock waves. In a companion study, IU School of Medicine researchers subjected a portion of one kidney in animal models to 8,000 shock waves, the very high end of clinical dosage. The result was large and sustained reductions of blood flow and function in both kidneys.
Blood flow is critical to healthy kidney function.
Many patients, particularly those over the age of 60, have some degree of kidney disease or infection when treated with lithotripsy for kidney stones. An earlier study from Austria showed that 40 percent of lithotripsy patients over the age of 60 have impaired blood flow and function more than 2 years after the treatment.