TREATMENT OF NEVUS OF OTA WITH THE Q-SWITCHED RUBY-LASER

Background. Nevus of Ota is a benign bluish gray-brown lesion of the eye and the surrounding skin that has been reported to occur in about 1 in 200 people in Japan. Prior treatments have either been ineffective or caused scarring. The Q-switched ruby laser can produce very short high-energy pulses and can selectively target cells that contain pigment, such as dermal melanocytes. Methods. We treated the skin lesions of 114 patients (25 male and 89 female) with nevi of Ota with a Q-switched ruby laser set to deliver pulses of 6 J per square centimeter of body-surface area at a wavelength of 694.3 nm, with a pulse duration of 30 nanoseconds. The interval between treatments ranged from three to four months. Five dermatologists who were not familiar with the patients independently compared a full set of pretreatment and post-treatment photographs of each patient and determined the percentage of pigment lightening of the affected areas using standard criteria. Results. Of the 35 patients who received four or five treatments, 33 had an excellent response (lightening of 70 percent or more), and 2 had a good response (lightening of 40 to 69 percent). Of the 31 patients who received three treatments, 4 had an excellent response, 26 a good response, and 1 a fair response (lightening of 10 to 39 percent). Of the 25 patients who received two treatments, 2 had an excellent response, 16 a good response, and 7 a fair response. Of the 23 patients who received one treatment, 3 had a good response, 13 a fair response, and 7 no response (lightening of 9 percent or less). No patient had hypertrophic or atrophic scarring; eight patients had postinflammatory hyperpigmentation for up to two months after the first treatment. Conclusions. Selective photothermolysis with the Q-switched ruby laser is a safe and effective method for lightening nevi of Ota. Multiple treatments increase the response rate.