title: Nonablative facial remodeling: erythema reduction and histologic evidence of new collagen formation using a 300-microsecond 1064-nm Nd:YAG laser.
abstract: BACKGROUND
  A variety of nonablative lasers have been used to improve skin color and toning. Evidence of new collagen has been seen. Using blinded observer analysis of electron microscopic changes, we have documented the effect of a nonablative Nd:YAG laser on collagen production and its relationship to patient age.
  
  
  METHODS
  Ultrastructural analysis of 9 patients showed a decrease in overall collagen fiber diameter in the papillary dermis at 1 month and 3 months after 3 treatment sessions. This is consistent with the formation of new collagen. Younger patients had a greater decrease in collagen fiber diameter compared with older patients. The change in collagen fiber diameter with time as well as the relationship between that change and the patient's age were statistically significant (P<.001). Photographic evaluation showed that those patients with preexisting erythema showed improvement in erythema along with an associated improvement in skin quality. There were no adverse events.
  
  
  CONCLUSIONS
  Microsecond Nd:YAG lasers appear to be safe for nonablative laser remodeling. Our study indicates that microsecond Nd:YAG lasers can produce new collagen formation in the papillary dermis. In addition, the condition of patients with erythema may be improved. Younger patients may form more new collagen compared with older patients with photodamage.
authors.forename: Chrys D
authors.initials: CD
authors.lastname: Schmults
authors.forename: Robert
authors.initials: R
authors.lastname: Phelps
authors.forename: David J
authors.initials: DJ
authors.lastname: Goldberg
mesh_terms: D000328:Adult; D000368:Aged; D003094:Collagen / Q000096:biosynthesis*; D004890:Erythema / Q000473:pathology / Q000628:therapy*; D024022:Fibrillar Collagens / Q000648:ultrastructure; D006801:Humans; D053685:Laser Therapy; D008854:Microscopy, Electron; D008875:Middle Aged; D016037:Single-Blind Method; D012867:Skin / Q000378:metabolism* / Q000473:pathology / Q000648:ultrastructure; D015595:Skin Aging; D016896:Treatment Outcome
chemical_list: D024022:Fibrillar Collagens; D003094:Collagen