title: Penetration of the laser light into the skin in vitro.
abstract: OBJECTIVE
  Knowledge of the optical parameters of the skin is important for all kinds of phototherapy. We analyzed penetration of laser light and proved different optical properties of in vitro specimens of normal skin and granular tissue from skin ulcers.
  
  
  METHODS
  An He-Ne laser (lambda = 632.8 nm, output 50 mW) and a semiconductor laser (lambda = 675 nm, output 21 mW) were used. The distribution of laser radiation was detected by a CCD camera and evaluated by the image analysis software DIPS.
  
  
  RESULTS
  Transmittance in granular tissue was about 2.5 times higher than that in normal skin. In the thickest skin sample (2 cm), approximately 0.3% of He-Ne laser and 2.1% of semiconductor laser light penetrated.
  
  
  CONCLUSIONS
  The results demonstrate the percentage of incident light penetrating the individual skin layers in different localizations on the skin surface, which is a decisive factor for the selection of the radiation dose.
authors.affiliation: Center of Molecular Biology and Medicine, Department of Medical Biophysics, Medical Faculty, Palacký University, Olomouc, Czech Republic. kol@tunw.upol.cz
authors.forename: H
authors.initials: H
authors.lastname: Kolárová
authors.forename: D
authors.initials: D
authors.lastname: Ditrichová
authors.forename: J
authors.initials: J
authors.lastname: Wagner
mesh_terms: D000042:Absorption; D000293:Adolescent; D000328:Adult; D006801:Humans; D053685:Laser Therapy; D007834:Lasers; D008297:Male; D010789:Phototherapy; D012542:Scattering, Radiation; D012867:Skin / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*; D012883:Skin Ulcer / Q000473:pathology / Q000628:therapy