Skin Pharmacol Physiol. 2009 Dec 14;23:79

Effect of Helium-Neon Laser Irradiation on Hair Follicle Growth Cycle of Swiss Albino Mice.
Shukla S, et al
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We report the results of a study carried out to investigate the effect of helium-neon (He-Ne) laser (632.8 nm) irradiation on the hair follicle regrowth cycle of testosterone-treated and untreated mice. Both histology and optical coherence tomography (OCT) were used for the measurement of hair follicle length and the relative percentage of hair follicles in different growth phases. A positive correlation was observed for the lengths of hair follicles measured by both methods. Further, the ratios of the lengths of hair follicles in the anagen and catagen phases obtained by both methods were nearly the same. However, the length of the hair follicles measured by both methods differed by a factor of 1.6, with histology showing smaller lengths. He-Ne laser irradiation (at approximately 1 J/cm(2)) of the skin of both the control and the testosterone-treated mice was observed to lead to a significant increase in % anagen, indicating stimulation of hair regrowth. The study also demonstrates that OCT can be used to monitor the hair follicle growth cycle, and thus hair follicle disorders or treatment efficacy during hair loss.

Z Hautkr.1977;52:1129

Alopecia areata: successful half-side treatment with DNCB

Happle R, Echternacht K.

In 46 patients with hai rloss due to alopecia areata, one side of the head was treated with weekly applications of DNCB. The treatment aim was mild contact dermatitis. The other side of the head served as control region. A treatment effect was noted in 36 patients: 22 patients showed regrowth of hair exclusively on the treated side, and in 14 patients hair regrowth was considerably faster and more dense on the treated side. In 8 patients no regrowth was observed, and in 2 patients regrowth occurred on both sides without any difference of intensity. The difference between both sides with regard to hair growth was seen in all of the 7 patients with moderate involvement and in 12 out of 13 patients with extensive involvement; but also in 17 out of 26 patients with alopecia areata totalis or fere totalis. The difference was noted, in the majority of cases, within 3 months…