29th Annual Meeting of the American Society of Photobiology

Downtown Marriot

Chicago, Il.

Predicting Epidermal Side Effects on all Skin Types with a Very Long Pulsed Diode (810nm) Wavelength Laser

Abstract-
Purpose: To evaluate the reliability of using the Fitzpatrick Skin Phototyping system to predict epidermal side effects with a diode laser designed for hair removal. Method: 40 adult subjects, representing all Fitzpatrick skin types (16-VI, 5-V, 5-IV, 5-III, 5-II, 4-I) were treated in the study. 24 test sites per subject, were marked and images obtained using digital images from a CCD camera. Test sites were treated with the diode laser system (modified LightSheer, developed by Palomar Medical Technologies, Inc. and Star Medical Technologies, Inc.) with combinations of very long pulsewidths (20-200 ms) and fluence levels (15-100 J/cm2). The diode laser utilizes contact cooling (ChillTipTM) to improve epidermal protection. Associated epidermal side effects were assessed at 1,2,3, and 6 months post laser treatment. Results: In darker skin types (Fitzpatrick Skin Types IV to VI) wide ranges of tolerated fluences were noted. Very long pulse-widths allow for all skin types to tolerate substantially higher fluences, allowing for darker skin types to be treated more safely and effectively. Transient pigment changes were the most common side effect, which is significantly reduced with longer pulsewidths. Textural changes occurred more often with high fluences, dark skin, and/or short pulsewidths. Textural changes did not occur without apparent acute epidermal damage. Conclusion: The Fitzpatrick Skin Typing system provides clinicians with a general guide to predicting laser induced epidermal side effects. A more precise skin typing system is needed, particularly in darker skin types (Fitzpatrick Skin Types IV to VI and sun-tanned skin) to assist in predicting safe laser treatment parameters to all patients, regardless of ethnic origin or skin color.

Keywords: Laser, Ethnic, Fitzpatrick Skin Type