title: Effect of low-level laser therapy on blood flow and oxygen- hemoglobin saturation of the foot skin in healthy subjects: a pilot study.
abstract: OBJECTIVE
  This study on healthy test subjects intends to show whether one-off Low-Level Laser Therapy (LLLT) has an instant effect on the perfusion or the oxygenation of the skin tissue. These possible instant effects may have an influence on the accelerated wound healing which is often observed after application of LLLT, in addition to the usual postulated effects of LLLT which occur with a time delay normally.
  
  
  METHODS
  The study was carried out double-blind and placebo-controlled in two batches of testing. The test subjects received one-off LLLT on a defined area of the arch of the foot. Simultaneously a placebo treatment was carried out on the corresponding contralateral area. In the first batch of tests, the blood flow was measured immediately before and after treatment using thermography and LDI. In the second batch of tests, the blood flow and the oxygen saturation were determined immediately before and after the treatment using an O2C device.
  
  
  RESULTS
  No evidence that the LLLT has a significant instant effect on the circulation or the oxygen saturation could be found.
  
  
  CONCLUSIONS
  No immediate effect of an LLLT on the perfusion or oxygenation situation is to be expected with physiologically normal starting conditions. An additional investigation should be carried out in which either the radiation dose is varied or the starting conditions are pathological (e.g. chronic wounds) in order to rule out immediate effects on circulation or oxygen saturation as the cause of the improved wound healing which is often observed.
authors.affiliation: Institute of Physiology and Experimental Pathophysiology, University of Erlangen-Nuremberg, Erlangen , Germany.
authors.forename: Franziska
authors.initials: F
authors.lastname: Heu
authors.forename: Clemens
authors.initials: C
authors.lastname: Forster
authors.forename: Barbara
authors.initials: B
authors.lastname: Namer
authors.forename: Adrian
authors.initials: A
authors.lastname: Dragu
authors.forename: Werner
authors.initials: W
authors.lastname: Lang
keywords: Laser-doppler flowmetry; Low-power laser therapy; Oximetry; Oxygen to see; perfusion