title: Laser fragmentation of foreign bodies in the urinary tract: an in vitro study and clinical application.
abstract: OBJECTIVE
  Foreign bodies of the urinary tract represent a urologic emergency. First-line treatment is endoscopic removal, but this is often impeded by restricted space, especially in the urethra. We postulated that foreign objects could be fragmented by Holmium:YAG laser and investigated its effect on objects of varying composition.
  
  
  METHODS
  In a specially designed stage flushed with physiologic saline, medical and non-medical objects of differing composition and diameter were subjected to fragmentation by Holmium:YAG at powers of 18 and 30 W. In additional thermal experiments, 5,000 J was applied to differing volumes of 0.9% sodium chloride. Experiments were repeated ten times.
  
  
  RESULTS
  With one exception (16 Ch silicon catheter) all medical objects were fragmented (latex urinary catheter, ureteral stents, and guidewires). Of non-medical objects (wood, steel, copper, graphite, and nylon) only copper wire was not amenable to laser dissection. These in vitro results were applied in two patients who presented with a pencil (wood and graphite) in the urethra or bladder. After Holmium:YAG laser fragmentation, the pencil could be removed by forceps each.
  
  
  CONCLUSIONS
  Foreign objects in the urinary tract can be fragmented with a Holmium:YAG laser. When foreign bodies are too big for initial endoscopic extraction, the clinician should consider this technique as a reasonable and atraumatic option to avoid open surgery.
authors.affiliation: Department of Urology, University of Tübingen, Hoppe-Seyler-Strasse 3, 72076 Tübingen, Germany. bedke@live.com
authors.forename: Jens
authors.initials: J
authors.lastname: Bedke
authors.forename: Stephan
authors.initials: S
authors.lastname: Kruck
authors.forename: David
authors.initials: D
authors.lastname: Schilling
authors.forename: Anton
authors.initials: A
authors.lastname: Matter
authors.forename: Marcus
authors.initials: M
authors.lastname: Horstmann
authors.forename: Karl-Dietrich
authors.initials: KD
authors.lastname: Sievert
authors.forename: Arnulf
authors.initials: A
authors.lastname: Stenzl
authors.forename: Udo
authors.initials: U
authors.lastname: Nagele
mesh_terms: D000368:Aged; D002404:Catheterization; D007172:Erectile Dysfunction; D005547:Foreign Bodies / Q000473:pathology / Q000628:therapy*; D006108:Graphite; D006358:Hot Temperature; D006801:Humans; D066298:In Vitro Techniques; D053685:Laser Therapy / Q000295:instrumentation* / Q000379:methods*; D053844:Lasers, Solid-State; D008297:Male; D008875:Middle Aged; D009757:Nylons; D012648:Self Care / Q000009:adverse effects; D012825:Silicon; D013232:Steel; D015607:Stents; D014552:Urinary Tract Infections; D014934:Wood
chemical_list: D009757:Nylons; D013232:Steel; D006108:Graphite; D012825:Silicon