title: A split face study to document the safety and efficacy of clearance of melasma with a 5 ns q switched Nd YAG laser versus a 50 ns q switched Nd YAG laser.
abstract: OBJECTIVE
  To determine the safety and efficacy of a 50 ns Q switched Nd YAG laser vs. a 5 ns Q switched Nd YAG laser for clearance of melasma. To compare subject satisfaction, efficacy, and comfort level between the two lasers.
  
  
  METHODS
  This is a prospective, randomized split face clinical study. The study was approved by the Scripps IRB. Ten healthy female subjects with moderate to severe melasma were enrolled. Each subject had three laser treatments one month apart. Patients were followed up approximately 1 month, 3 months, and 6 months after the final laser treatment. A treatment session consisted of a microdermabrasion, 1064 nm QS laser, and topicals. Subjects were asked to rate treatment pain based on a numerical scale range 0-10 (0 = no pain and 10 = worst pain). A melasma area and severity index (MASI) grading system was applied. Also, melanin measurements were acquired by a reflectance spectrophotometer. Side effects were documented during the study including post treatment erythema.
  
  
  RESULTS
  Eight patients completed the study. Subjects showed improvement on both sides of the face. From baseline to 1 month post the final laser treatment, the average MASI scores showed a 16% reduction for the 50 ns QS 1064 nm laser vs. a 27% reduction for the 5 ns QS 1064 nm laser (both significant versus baseline pigment, P < 0.05). This difference in MASI scores between the two lasers was not statistically significant (P = 0.87930). Laser treatments displayed mild erythema that resolved after one day. The melanin meter measurements showed a reduction in pigment readings on both sides. Three months after the final treatment there was some relapse in the melasma, as the mean pigment reduction fell to 12% for the 50 ns laser and 11% for the 5 ns laser. By 3 months pigment reduction was not statistically significant for either laser, and no significant differences in pigment reduction were noted between the two pulse durations. There was a statistically significant difference (P < 0.05) in pain scores reported by the subjects (scale 0-10), the mean pain score for 50 ns QS 1064 nm laser was 1.2 and for the 5 ns QS 2.9 the score was 2.9.
  
  
  CONCLUSIONS
  In this study, we showed that a combination of microdermabrasion, QS1064 nm laser, and topicals decreased the MASI and meter scores without clinically significant side effects. Moreover, the longer pulsed Q switched 1064 nm laser i.e. (50 ns) was associated with less pain than its shorter pulse width counterpart.
authors.affiliation: Dermatology Department, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Salman M S
authors.initials: SM
authors.lastname: Alsaad
authors.forename: E Victor
authors.initials: EV
authors.lastname: Ross
authors.forename: Vineet
authors.initials: V
authors.lastname: Mishra
authors.forename: Lee
authors.initials: L
authors.lastname: Miller
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003869:Dermabrasion; D005145:Face; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053685:Laser Therapy / Q000009:adverse effects / Q000295:instrumentation*; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008297:Male; D008548:Melanosis / Q000473:pathology / Q000601:surgery*; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome; D055815:Young Adult
keywords: QS Nd: YAG 1064 nm laser; melasma