title: Photothermolysis of blood vessels using indocyanine green and pulsed diode laser irradiation in the dorsal skinfold chamber model.
abstract: OBJECTIVE
  For the treatment of vascular lesions, the use of laser light absorbed by the endogenous chromophore hemoglobin may still be improved.
  
  
  METHODS
  Laser treatment (lambda(em) = 805 nm; fluence rate: 106 kW/cm2; fluence: 3.2 J/cm2 (3 milliseconds)), of blood vessels directly after i.v. application of indocyanine green (ICG) (ICG-concentration: 0, 2, or 4 mg/kg body weight (b.w.)) (n = 14,117) was investigated in the skinfold chamber model. Vessel diameters (1-351 microm) were measured using intravital fluorescence microscopy up to 24 hours following irradiation. Histology was taken 1 or 24 hours after irradiation. Results were compared to a mathematical model based on the finite element method.
  
  
  RESULTS
  The reduction of blood vessel perfusion was proportional to ICG-concentration and pulse duration; only a 30 milliseconds pulse duration (2 or 4 mg/kg b.w. ICG-concentration) induced a loss of perfusion even of blood vessels with a diameter <30 microm. Histology revealed photocoagulation of blood vessels up to 24 hours. Results were in agreement with mathematical calculations.
  
  
  CONCLUSIONS
  ICG-mediated laser irradiation induces irreversible photocoagulation of blood vessels of all diameters in this model.
authors: Department of Dermatology, Regensburg University Medical Center, 93042 Regensburg, Germany. philipp.babilas@klinik.uni-regensburg.de
authors: Philipp
authors: P
authors: Babilas
authors: Gal
authors: G
authors: Shafirstein
authors: Jürgen
authors: J
authors: Baier
authors: Vivien
authors: V
authors: Schacht
authors: Rolf-Markus
authors: RM
authors: Szeimies
authors: Michael
authors: M
authors: Landthaler
authors: Wolfgang
authors: W
authors: Bäumler
authors: Christoph
authors: C
authors: Abels
mesh_terms: D000818:Animals; D004396:Coloring Agents / Q000494:pharmacology*; D006224:Cricetinae; D062109:Dermatologic Surgical Procedures; D020342:Finite Element Analysis; D007208:Indocyanine Green / Q000494:pharmacology*; D017075:Laser Coagulation / Q000379:methods*; D008297:Male; D008833:Microcirculation; D008856:Microscopy, Fluorescence; D012867:Skin / Q000098:blood supply
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green