Lithotripsy - History
The concept of using shock waves to fragment stones had its origin in research done in Germany during the 1960s. Researchers found that the pitting of aircraft wings following supersonic flight was caused by collision of the airplane wing with rain drops. ESWL was introduced into the United States in 1984.
The use of sound waves to destroy kidney stones is based on the destructive force generated when a shock wave in fluid suddenly hits a substance that has different properties, such as a kidney stone. The shock waves pass efficiently through fluid mediums and can be focused so they strike small objects.