title: Effects of gallstone solvents on commonly used catheters.
abstract: OBJECTIVE
  To determine what interaction and effect different cholesterol gallstone solvents have on catheters used for gallstone chemolysis.
  
  
  METHODS
  Five types of catheters used for biliary procedures were chosen: polyethylene, Percuflex, silicon, Silitek, and polyurethane. The solvents chosen were methyl tert-butyl ether, ethyl propionate, isopropyl acetate, and N-propyl acetate. After incubation of the catheters in the solvents for 72 hours, they were air dried. Weight and area changes were determined for each catheter. Additionally, carbon-13 nuclear magnetic resonance (NMR) spectroscopy was performed for analysis of composition changes.
  
  
  RESULTS
  Three catheters--silicone, Silitek, and polyurethane--showed changes in their physical characteristics that would make them less desirable for stone chemolysis. The silicone catheter showed changes in elastic texture as well as marked weight reduction. The Silitek and polyurethane catheters had similar, but less dramatic changes. C-13 NMR analysis of collected solvents showed that commonly used plasticizers were leached out of some catheters.
  
  
  CONCLUSIONS
  These results suggest that all catheters are not suitable for use with all solvents. The choice of catheter should be made based on the solvent in use. The polyethylene catheter performed best under the conditions and endpoints used in this study.
authors.affiliation: Department of Radiology, University of Oklahoma Health Science Center, Oklahoma City.
authors.forename: C A
authors.initials: CA
authors.lastname: Long
authors.forename: S K
authors.initials: SK
authors.lastname: Teplick
authors.forename: J C
authors.initials: JC
authors.lastname: Brandon
authors.forename: G H
authors.initials: GH
authors.lastname: Harb
authors.forename: K
authors.initials: K
authors.lastname: Yan
authors.forename: M L
authors.initials: ML
authors.lastname: Baker
mesh_terms: D002404:Catheterization / Q000295:instrumentation*; D002769:Cholelithiasis / Q000628:therapy*; D006801:Humans; D011095:Polyethylenes; D011140:Polyurethanes; D012828:Silicones; D012997:Solvents / Q000494:pharmacology*
chemical_list: D011095:Polyethylenes; D011140:Polyurethanes; D012828:Silicones; D012997:Solvents