Effect of visible and infrared polarized light on the healing process of full-thickness skin wounds: an experimental study.
OBJECTIVE
Polarized light has already been experimentally and clinically used in an effort to promote wound healing, but the findings have been equivocal. The aim of this study was to evaluate the effect of visible and infrared polarized light of a specific range of wavelength (580-3400 nm) on the secondary healing of full-thickness skin wounds in rats.


METHODS
Forty male Wistar rats were used, divided in two groups of 20 animals each. A standardized open full-thickness skin wound was created on the back of each animal. In the first group the rats were exposed to polarized light (40 mW/cm(2) and 2.4 J/cm(2)) for 7 min on a daily basis (total daily dose = 16.8 J/cm(2)), while the second group acted as controls. Clinical and histological evaluation of wound healing were performed on days 5, 10, 15, and 20 post-wound. The size of the wounds was measured with the use of planimetry, whereas epithelialization, inflammatory response, neovascularization, and collagen formation were histologically assessed.


RESULTS
According to our findings, the group exposed to light therapy showed statistically significantly faster epithelialization seen on days 10 and 15 post-wound compared to controls, as well as better quality of the healing process (although not statistically significantly) at all time points.


CONCLUSIONS
In conclusion, this specific fraction of polarized light seems to have beneficial effects on wound healing, leading to faster epithelialization and qualitatively better wound healing.
Iordanou
Panagiota
P
Technological Educational Institute of Athens, Ioannina University School of Medicine, Ioannina, Greece.
Lykoudis
Efstathios G
EG
Athanasiou
Athanasios
A
Koniaris
Efthymios
E
Papaevangelou
Maria
M
Fatsea
Theodora
T
Bellou
Panagiota
P
D000818:Animals; D004195:Disease Models, Animal; D007259:Infrared Rays; D008027:Light; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012867:Skin / Q000528:radiation effects*; D014945:Wound Healing / Q000528:radiation effects*; D014947:Wounds and Injuries / Q000532:radiotherapy*