Q-Switched Laser Treatment for Freckles in Individuals with Skin Type V

Abstract

Freckles are usually thought of as small, poorly marginated, well-circumscribed, pale brown macules present on sun-exposed skin areas in fair-complexioned individuals. However, freckles also occur in patients who have skin types IV and V, and there is a risk of prolonged depigmentation after treatment with a Q-switched laser emitting wavelengths of 532 nm. Unlike in fair-complexioned patients with light eyes and auburn hair who respond well but relapse in a matter of weeks, patients with skin type V show a permanent and satisfactory response to laser therapy. However, lower energies have to be used to prevent permanent hypopigmentation, which stands out in patients with skin of color. It is advisable to perform test spots on freckles before treating the entire face. After treatment, freckles can become of an ash white color. Test spots can be evaluated after 6 weeks. Sunscreen should be mandatory after the procedure. Additionally, freckles should be differentiated from lentigines by Wood lamp examination, where the superficial freckles get ac­centuated. Lentigines are treated using wavelengths of 1,064 nm.

Fluorescent polymer markers photoconvertible with a 532 nm laser for individual cell labeling

“…The most common discrete wavelength laser in the green range for imaging cells and labels with sufficient resolution is 532 nm one. This wavelength is widely used in cell cytometry [38], different types of fluorescence microscopy [39], as well as in cosmetology [40]. The popularity of the 532 nm laser is due to the advantages including the availability, low cost and relatively highpower values.…”