title: The comparison of effects between pulsed and CW lasers on wound healing.
abstract: OBJECTIVE
  In order to evaluate the effects of pulsed continuous wave (CW) laser and detect the role of wound healing in rats using both pulsed and CW 635-nm low-level laser therapy (LLLT), a pilot study was undertaken.
  
  
  BACKGROUND
  Some acceleration effects of wound healing on animals were found after treatment using various lasers with CW. There are other reports, however, using pulsed CW laser to evaluate the effects of wound healing in rats.
  
  
  METHODS
  An elliptic wound was created aseptically with a scalpel on the shaved back of the rats after anesthesia. The rats treated were restrained in a Plexiglas cage without anesthesia during the laser irradiation period. An Erchonia pulse laser (635 nm) was used in the experiment. The laser beam was delivered through an expander. The percentage of relative wound healing was calculated.
  
  
  RESULTS
  The percentage of relative wound healing was 4.32 in 100 Hz, 3.21 in 200 Hz, 3.83 in 300 Hz, 2.22 in 400 Hz, 1.73 in 500 Hz and 4.81 in CW.
  
  
  CONCLUSIONS
  LLLT using pulsed, CW laser at the appropriate dosimetry and frequency can provide acceleration in wound healing in rats. The 100-Hz frequency had a better effect than other pulse frequencies used in the study. The effects of treatment using CW laser was higher than pulse frequency. The frequency of pulsed CW laser was not found to increase wound healing in rats compared with normal CW laser, as reported in our previous studies.
authors.affiliation: Laser Medicine Research Section, Biological and Medical Research Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia. watban@kfshrc.edu.sa
authors.forename: Farouk A H
authors.initials: FA
authors.lastname: Al-Watban
authors.forename: X Y
authors.initials: XY
authors.lastname: Zhang
mesh_terms: D000818:Animals; D028022:Low-Level Light Therapy / Q000295:instrumentation / Q000379:methods; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012867:Skin / Q000293:injuries; D014945:Wound Healing / Q000528:radiation effects*