title: Long-term results after CO2 laser skin resurfacing: a comparison of scanned and pulsed systems.
abstract: BACKGROUND
  New laser technology permits the use of high-energy pulsed and continuous-wave carbon dioxide (CO2) lasers with flashscanners to treat rhytides.
  
  
  OBJECTIVE
  We compared the efficacy and side effects of the two leading CO2 lasers used in skin resurfacing.
  
  
  METHODS
  A total of 28 patients with facial rhytides were treated with either the UltraPulse or SilkTouch laser systems; in five additional patients, contralateral cosmetic units were treated with one system or the other in a direct comparison of the lasers.
  
  
  RESULTS
  We compared photographs taken before and after treatment, and a lessening of facial wrinkling was noted in all subjects. In some subjects improvement was confirmed by optical profilometry methods. Biopsy specimens in representative patients showed that immediate thermal damage was limited to 180 microns. Long-term postoperative specimens showed changes in the papillary dermis consistent with new collagen deposition and reduction of pretreatment solar elastosis. Posttreatment facial erythema was noted in half the patients for up to 2 months; transient hyperpigmentation was observed in one third of the treated areas.
  
  
  CONCLUSIONS
  Although the SilkTouch system produced more immediate thermal damage, there were no significant differences in efficacy or adverse effects between the lasers. Our results suggest that both laser systems, used with appropriate settings, are capable of safely smoothing the skin surface.
authors.affiliation: Dermatology Laser Center, Harvard Medical School, Boston, MA 02114, USA.
authors.forename: E V
authors.initials: EV
authors.lastname: Ross
authors.forename: M C
authors.initials: MC
authors.lastname: Grossman
authors.forename: D
authors.initials: D
authors.lastname: Duke
authors.forename: J M
authors.initials: JM
authors.lastname: Grevelink
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D003094:Collagen / Q000032:analysis; D062109:Dermatologic Surgical Procedures; D004890:Erythema / Q000209:etiology; D005145:Face / Q000601:surgery; D005260:Female; D006801:Humans; D017495:Hyperpigmentation / Q000209:etiology; D053685:Laser Therapy / Q000009:adverse effects / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010781:Photography; D019651:Plastic Surgery Procedures / Q000009:adverse effects / Q000379:methods*; D012867:Skin / Q000473:pathology; D015595:Skin Aging
chemical_list: D003094:Collagen