Avram Marc R, Rogers Nicole E
Cornell Department of Dermatology, New York, NY, USA.
J Cosmet Laser Ther. 2009 Jun;11(2):110-7. doi: 10.1080/14764170902842531.
Low-level laser therapy (LLLT) is a new therapy for the treatment of hair loss. It has received enormous media attention and tremendous marketing budgets from companies that sell the devices, but no independent, peer-reviewed studies have demonstrated its efficacy in this application. Here we investigate the efficacy of LLLT in enhancing hair growth.
A total of seven patients were exposed to LLLT twice weekly for 20 minutes each time over a period of 3-6 months. Five patients were treated for a total of 3 months and two were treated for 6 months. Videomicroscopic images were taken at baseline, 3 months, and 6 months, and analyzed for changes in vellus hair counts, terminal hair counts, and shaft diameter. Both videomicroscopic and global images underwent blinded review for evidence of subjective improvement. Patients also answered questionnaires assessing hair growth throughout the study. Neither patients nor physicians conducting the study received any financial compensation.
The results indicate that on average patients had a decrease in the number of vellus hairs, an increase in the number of terminal hairs, and an increase in shaft diameter. However, paired i-testing indicated that none of these changes was statistically significant. Also, blinded evaluation of global images did not support an improvement in hair density or caliber.
LLLT may be a promising treatment option for patients who do not respond to either finasteride or minoxidil, and who do not want to undergo hair transplantation. This technology appears to work better for some people than for others. Factors predicting who will most benefit are yet to be determined. Larger, longer-term placebo-controlled studies are needed to confirm these findings, and demonstrate statistical significance, or refute them altogether.
低能量激光疗法（LLLT）是一种治疗脱发的新方法。它受到了媒体的广泛关注，销售该设备的公司投入了巨额营销预算，但尚无独立的、经过同行评审的研究证明其在这一应用中的疗效。在此，我们研究低能量激光疗法促进头发生长的疗效。
共有7名患者接受低能量激光疗法，每周两次，每次20分钟，持续3至6个月。5名患者共治疗3个月，2名患者治疗6个月。在基线、3个月和6个月时拍摄视频显微镜图像，并分析毳毛数量、终毛数量和毛干直径的变化。对视频显微镜图像和整体图像进行双盲评估，以寻找主观改善的证据。患者在整个研究过程中还回答了评估头发生长情况的问卷。患者和进行研究的医生均未获得任何经济补偿。
结果表明，患者平均毳毛数量减少，终毛数量增加，毛干直径增大。然而，配对t检验表明，这些变化均无统计学意义。此外，对整体图像的双盲评估也不支持头发密度或粗细有改善。
对于对非那雄胺或米诺地尔均无反应且不想接受毛发移植的患者，低能量激光疗法可能是一种有前景的治疗选择。这项技术对一些人似乎比对另一些人效果更好。预测谁将最受益的因素尚待确定。需要开展更大规模、更长期的安慰剂对照研究来证实这些发现，并证明其统计学意义，或者完全推翻这些发现。
