Pulsed alexandrite laser technology for noninvasive hair removal

Determination of the efficacy of pulsed Alexandrite Laser technology for rapid noninvasive hair removal.

Although previous studies have already shown that Ruby lasers are capable of noninvasive hair removal, a technology for the substantial increase of treatment speed is of great interest.

We have used a 2 msec free running pulsed Alexandrite (lambda = 755 nm) laser operated at a repetition rate of up to 5 pps at energy fluences of 25-40 J/cm2 to treat a wide range of body sites on 126 patients in conjunction with a fiber delivery system and a transparent target ruler. A transparent gel was used as epidermal heat sink. The study lasted 15 months. Pretreatment as well as follow-up hair count per cm2 was performed to determine the level of success. Treatments were repeated when 1-2 mm growth was observed.

The average hair count before the second treatment was found to be close to 65% of the pretreatment count. The average hair count 3 months after the last treatment, was found to be lower than 12%. The interval between treatments ranged from 4 weeks to 3 1/2 months.

The 2 msec pulsed Alexandrite laser technology is effective for the removal of unwanted hairs, ranging from fair to dark, except when hairs are absent in the shaft depending on the stage of their growth cycle. This results in the necessity of a few treatments or touchups. Adverse effects are minimal and transient.