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Treatment of benign pigmented lesions using a long-pulse alexandrite laser.

BACKGROUND
To evaluate the efficacy of a novel long-pulse alexandrite laser with contact cooling in the treatment of benign pigmented lesions.


METHODS
Five patients were enrolled in the study. All patients presented with epidermal pigmented lesions on the arms, hands, chest, or legs. Patients were all female with a mean age of 59 years. At the initial evaluation, baseline pigment readings were determined with a pigment meter. Test spots were performed with escalating doses of alexandrite laser (ClearScan ALX, Sciton, Palo Alto, CA) deployed by a 7-mm spot equipped with a 30 mm x 30 mm scanner and a 10-ms pulse duration. Contact cooling was used, and temperature was maintained at 18°C to 20°C. Patients returned 4 to 7 days after test spots for evaluation for the purpose of optimizing settings. The highest settings that allowed for epidermal preservation and crusting of the hyperpigmented lesions were applied for the remainder of the treatment zones. Determinations of improvement were made by evaluation of photographs with standard settings using polarized and nonpolarized images. At each appointment, baseline pigment measurements were made to ensure there were no significant changes between treatment sessions. Two treatment sessions were performed approximately 4 weeks apart, and the final evaluation was 3 months after the final treatment.


RESULTS
Evaluation by a panel of blind observers determined a mean improvement of approximately 30%. Darker lesions responded better than lighter lesions. So-called low-contrast lesions performed the poorest. Pain was approximately 2/10 with the use of 5% lidocaine numbing cream applied approximately 45 minutes before each procedure. Pain was most severe where there was underlying hair.


CONCLUSION
A long-pulse alexandrite laser equipped with contact cooling can achieve significant pigmentation improvement.