title: A case series of facial depigmentation associated with low fluence Q-switched 1,064 nm Nd:YAG laser for skin rejuvenation and melasma.
abstract: OBJECTIVE
  In recent years, "laser toning" using low fluence, large spot size, multiple passed Q-switched 1,064 nm Nd:YAG laser has gained much popularity in Asian countries for non-ablative skin rejuvenation and the treatment of melasma. This case series highlights one of the complications associated with laser toning, which is facial depigmentation.
  
  
  METHODS
  Fourteen patients with laser toning-associated facial depigmentation were assessed with cross-polarized and ultraviolet (UV) photographic images. The laser toning regimens received by these patients, as well as the treatment given for depigmentation, were analyzed retrospectively.
  
  
  RESULTS
  All 14 patients were Chinese females, 9 of whom received laser toning for non-ablative skin rejuvenation and the other 5 for melasma. The treatment regimens received by these patients were highly variable. The total number of treatments received ranged from 6 to 50 (mean 22.07). In all cases, UV photographic images demonstrated facial mottled depigmentation. Laser toning failed to significantly improve melasma in all five patients. Five patients received targeted narrowband UVB for depigmentation with good clinical results.
  
  
  CONCLUSIONS
  Laser toning with low fluence Q-switched 1,064 nm Nd:YAG laser for skin rejuvenation and melasma can be associated with mottled depigmentation. With laser toning being frequently performed, this complication may become more commonly encountered in clinical practice. The depigmentation can appear after only a few treatment sessions, and can cause much disfigurement, especially in cases with background melasma. Further studies on laser toning are needed with the view to optimizing efficacy and minimizing side-effects.
authors.affiliation: Division of Dermatology, Department of Medicine, University of Hong Kong, Hong Kong SAR, China.
authors.forename: Nicola P Y
authors.initials: NP
authors.lastname: Chan
authors.forename: Stephanie G Y
authors.initials: SG
authors.lastname: Ho
authors.forename: Samantha Y N
authors.initials: SY
authors.lastname: Shek
authors.forename: Chi K
authors.initials: CK
authors.lastname: Yeung
authors.forename: Henry H
authors.initials: HH
authors.lastname: Chan
mesh_terms: D000328:Adult; D044466:Asian People; D002681:China; D005260:Female; D006801:Humans; D053844:Lasers, Solid-State; D028022:Low-Level Light Therapy; D008548:Melanosis / Q000532:radiotherapy*; D008875:Middle Aged; D012189:Retrospective Studies; D015595:Skin Aging