Abstract

Recently, encouraging results have been obtained using a Ruby laser to depilate unwanted hair. Ruby laser with a wavelength of 694 nm is well absorbed by melanin and is poorly absorbed by haemoglobin (1). It is thought that melanin in hair follicles acts as a chromophore which can be targeted to achieve selective photothermolysis (2) of hair follicles while sparing adjacent tissues. A study using Q-switched Ruby laser on guinea pig skin by Polla et al (3) showed that melanin was the fundamental target of energy absorption and at appropriate radiant exposures, it injured melanosomes without inducing any visible damage to unmelanized organelles. A clinical study performed by Gault et al (4), using a Ruby laser (694 nm, continuous mode with pulse width of 600 microseconds), resulted in a reduction of the overall hair density by 58% in a follow up of up to one year. Grossman et al (5) also demonstrated that Ruby Laser (694 nm, continuous mode with pulse width of 270 microseconds) produced a growth delay in hair follicles, with 4 out of 13 dark haired subjects having less than 50% regrowth of hair at 6 months.

© 1997 Optical Society of America