Photoepilation With The New Pulsed Diode Apex 800 Laser System With Subzero Contact Cooling Jeffrey D. Parks, MD
Meg E. Pierce, PA-C Parks Dermatology Center
Ormond Beach, Florida
Introduction: This study reports treatment using the Apex 800 diode laser system, a high power, long pulsed diode with a subzero contact cooling and a wavelength of 800 nm for laser hair reduction. Laser hair reduction operates on the principles of selective photothermolysis. This process combines the selective absorption of light energy by the melanin in the hair follicle with suitable fluences and pulse durations to allow selective injury to the hair follicle while sparing skin.
Methods: This prospective study looked at hair reduction in 36 healthy subjects (33 women and 3 men) between the ages of 28 and 78 years old. All subjects had tried various hair removal methods in the past without satisfactory results. These methods included shaving, tweezing/plucking, waxing, electrolysis, prescription medications and other hair laser machines. Eligible subjects had black or brown hair, Fitzpatrick skin type I - IV and lacked exclusion criteria. All patients were treated with the Apex 800 diode laser (Iridex Corporation, Mountain View, CA) at 800nm wavelength setting using a 9mm ColdTip cooling handpiece set at 0 degrees Celsius and a repetition rate of 1.5 Hz.
Results: Eighteen subjects completed three treatment sessions, eight subjects completed two treatment sessions and ten subjects completed only one treatment session. The average hair reduction of all sites was 41% after the first treatment, 55% after the second treatment and 68% after the third treatment. Hair reduction varied by both treatment site (axilla, face, legs, back, neck, arms, abdomen, and bikini) and number of treatment sessions. Hair reduction continued to improve with each subsequent treatment.
Discussion: The data confirm that the Apex 800 diode laser, with the ColdTip handpiece providing contact skin cooling, provides a safe and effective method for hair reduction in a heterogeneous population. The good hair reduction rates (68% on average) seen in this study are comparable with responses reported for other high powered 800 nm diode lasers and other wavelengths (6). Hair reduction over 75% was noted in different treatment sites in 40% of subjects.
Active cooling is vital in hair removal treatment. Skin cooling was maximized with the use of chilled gel and pre-, parallel, and post-treatment contact of the ColdTip hand piece with the skin. Parallel cooling extracts heat during the pulse allowing even greater levels of epidermal protection. This excellent cooling allowed the maximum energy density (50J/cm2) to be used on some patients to improve outcome without adverse side effects.
Overall, hair reduction was evident in all skin type groups and similar among subjects with varied hair diameter. Treatments were well tolerated with minimal to no post-treatment side effects. Clinical outcome continued to improve with subsequent treatments and subjects were pleased with the cosmetic results.