title: Temperature controlled CO(2) laser welding of soft tissues: urinary bladder welding in different animal models (rats, rabbits, and cats).
abstract: OBJECTIVE
  Laser welding of tissues is a method of closure of surgical incisions that, in principle, may have advantages over conventional closure methods. It is a noncontact technique that introduces no foreign body, the closure is continuous and watertight, and the procedure is faster and requires less skill to master. However, in practice, there have been difficulties in obtaining strong and reliable welding. We assumed that the quality of the weld depends on the ability to monitor and control the surface temperature of the welded zone during the procedure. Our objective was to develop a "smart" fiberoptic laser system for controlled temperature welding.
  
  
  METHODS
  We have developed a welding system based on a CO(2) laser and on infrared transmitting AgClBr fibers. This fiberoptic system plays a double role: transmitting laser power for tissue heating and noncontact (radiometric) temperature monitoring and control. The "true" temperature of the heated tissue was determined by using an improved calibration method. We carried out long-studies of CO(2) laser welding of urinary bladders in various animal models. Cystotomies were performed on the animals, and complete closure of the bladder was obtained with a surface temperature of 55 +/- 5 degrees C at the welding site.
  
  
  RESULTS
  In early experiments on 31 rats, the success rate was 73%. In later experiments with 10 rabbits and 3 cats, there was an 80% and a 100% success rate, respectively.
  
  
  CONCLUSIONS
  The success rate in these preliminary experiments and the quality of the weld, as determined histologically, demonstrate that temperature controlled CO(2) laser welding can produce effective welding of tissues. The fiberoptic system can be adapted for endoscopic laser welding.
authors.affiliation: Department of Urology, Centre Hospitalier Pontchaillou, Rennes, France.
authors.forename: B
authors.initials: B
authors.lastname: Lobel
authors.forename: O
authors.initials: O
authors.lastname: Eyal
authors.forename: N
authors.initials: N
authors.lastname: Kariv
authors.forename: A
authors.initials: A
authors.lastname: Katzir
mesh_terms: D000818:Animals; D002245:Carbon Dioxide; D002415:Cats; D005260:Female; D005336:Fiber Optic Technology; D006358:Hot Temperature; D053685:Laser Therapy; D008297:Male; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D013536:Suture Techniques; D001743:Urinary Bladder / Q000473:pathology / Q000601:surgery*
chemical_list: D002245:Carbon Dioxide