title: Fragmentation of biliary calculi by means of extracorporeally generated piezoelectric shock waves.
abstract: A new extracorporeal piezoelectric lithotripter was tested for its gallstone disintegration capability. A total of 177 surgically removed gallbladder stones were submitted to piezoelectric shock-wave treatment. Prior to shock-wave application, the diameter, weight, and volume of all the stones and CT density and MR signal intensity of selected stones were determined. After shock-wave application, the chemical composition of the stones was investigated by x-ray diffractometry and/or infrared spectrometry. All the stones (maximum diameter 6-30 mm) were successfully fragmented; calculi with a maximum diameter of 17 mm, a maximum weight of 1800 mg, and a maximum volume of 2 cc were regularly disintegrated into fragments less than or equal to 4 mm. The number of shock waves required correlated most closely with volume (r = 0.82, P less than 0.001), weight (r = 0.81, P less than 0.001) and, to a somewhat lesser degree, diameter (r = 0.62, P less than 0.001). No correlation was found between the chemical composition, CT density, or MR intensity of the calculi and the number of pulses needed for fragmentation.
authors.affiliation: Department of Medicine, University of Erlangen-Nuremberg, F.R.G.
authors.forename: C
authors.initials: C
authors.lastname: Ell
authors.forename: W
authors.initials: W
authors.lastname: Kerzel
authors.forename: H
authors.initials: H
authors.lastname: Langer
authors.forename: N
authors.initials: N
authors.lastname: Heyder
authors.forename: E
authors.initials: E
authors.lastname: Foerster
authors.forename: W
authors.initials: W
authors.lastname: Domschke
mesh_terms: D002769:Cholelithiasis / Q000032:analysis / Q000628:therapy*; D006801:Humans; D008096:Lithotripsy / Q000379:methods*; D014465:Ultrasonics