3.3 Lllt for Hair Regrowth

One of the most commercially successful applications of LLLT is the stimulation of hair regrowth in balding individuals. The photobiomodulation activity of LLLT can cause more hair follicles to move from telogen phase into anagen phase. The newly formed hair is thicker and also more pigmented. The Hairmax Lasercomb (Fig. 5e) was shown to give a statistically significant improvement in hair growth in a randomized, double-blind, sham device-controlled, multicenter trial in 110 men with androgenetic alopecia and this led to FDA clearance for efficacy (FDA 510(k) number K060305) [7]. The teeth of the comb are supposed to improve the penetration of light though the existing hair to the follicles requiring stimulation (Fig. 5f). Recently, a different LLLT device received FDA clearance in women suffering from androgenetic alopecia (FDA 510(k) numberK091496). This group of patients have fewer treatment options than men. In order to make the application of light to the head more user-friendly and increase patient compliance, companies have developed "laser caps" (Fig. 5g).

Conclusion

Advances in design and manufacturing of LLLT devices in the years to come will continue to widen the acceptability and increase adoption of the therapy among the medical profession, physical therapists and the general public. While the body of evidence for LLLT and its mechanisms is still weighted in favor of lasers and directly comparative studies are scarce, ongoing work using non-laser irradiation sources is encouraging and provides support for growth in the manufacture and marketing of affordable home-use LED devices. The almost complete lack of reports of side effects or adverse events associated with LLLT gives security for issues of safety that will be required [1].

LLLT will steadily progress to be better accepted by both the medical profession and the general public at large. The number of published negative reports will continue to decline as the optimum LLLT parameters become better understood, and as reviewers and editors of journals become aware of LLLT as a scientifically based therapy. On the clinical side, the public's distrust of big pharmaceutical companies and their products is also likely to continue to grow. This may be a powerful force for adoption of therapies that once were considered as "alternative and complementary," but now are becoming more scientifically accepted. LLLT is not the only example of this type of therapy, but needle acupuncture, transcranial magnetic stimulation and microcurrent therapy also fall into this class. The day may not be far off when most homes will have a light source (most likely a LED device) to be used for aches, pains, cuts, bruises, joints, and which can also be applied to the hair and even transcranially to the brain [15].

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