Allison K P, Kiernan M N, Waters R A, Clement R M
University Hospitals Birmingham NHS Trust, Raddlebarn Road, Birmingham, B29 6JD.
Lasers Med Sci. 2003;18(3):165-70. doi: 10.1007/s10103-003-0266-6.
Lasers have been established as effective treatment for hair removal, with possible long-term suppression of hair growth in treated areas. The purpose of this study was to assess long-term hair regrowth after treatment with the ruby laser. Volunteers recruited into the 1997-99 study were divided between three treatment groups, each having left and right treatment sides. Two treatments were given on both sides at monthly intervals. A third treatment was given randomly to one side. Hair counts of the experimental sites were made at monthly intervals for 1 year. The three patient groups were: top lip (25), axillae (25) and legs (19). Long-term hair reduction was achieved in all patients. A single treatment reduced hair counts by up to 75. Three treatments had an impact for 2 additional months, but not long term. Unexpected spontaneous hair reduction was found 5 months following treatment and lasted 2 months. This ruby laser produced a persistent two-thirds reduction in hair count over 8 months of follow-up. Extension of the follow-up to 12 months did not show significant regrowth. Existing experimental data, together with the results of this study, suggest that hair shaft damage is the key feature in achieving damage to the hair-producing mechanism. The correlation of treatment success and anagen growth phase is less likely.
