title: Biophysical evaluation of fractional laser skin resurfacing with an Er:YSGG laser device in Japanese skin.
abstract: BACKGROUND
  Ablative fractional laser skin resurfacing (FLSR) has recently been used for the amelioration of acne scars, and previous studies have shown clinical effectiveness. Despite its extensive use, few studies have focused on the associated changes in biophysical properties of the epidermis. Herein, we evaluate transepidermal water loss, sebum levels, skin hydration, and skin elasticity, following FLSR treatments with an Er:YSGG laser device (Pearl FractionalTM, Cutera Inc., Brisbane, CA), employing non-invasive measurements.
  
  
  METHODS
  Five Japanese patients with facial acne scars underwent one FLSR session. Some acne scars appeared to become less obvious as a consequence of the treatment. All patients were aware of a feeling of skin tightness in treated areas.
  
  
  RESULTS
  Objective measurements on the lower lateral angle of the eye and on the inner cheeks were evaluated at baseline and at 3 days, 1 week, and 4 weeks after FLSR. Transepidermal water loss showed a significant two-fold (100%) increase at day 3, but had returned to almost the baseline level at week 4 in both areas. Sebum secretion showed a 50% increase at day 3, but had returned to the baseline level after day 7. Skin hydration showed a significant decrease at day 3, but had returned to the baseline level by day 7, and showed significant improvement at the end of the study. Skin elasticity (R2) was still at baseline on day 3, but showed some improvement--an increase of at least 30%--at the end of the study.
  
  
  CONCLUSIONS
  Based on our findings, we believe that FLSR should be performed no more than once a month to allow sufficient time for the damaged skin to recover its barrier function in most areas of the face.
authors.affiliation: Department of Dermatology, Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan.
authors.forename: Utako
authors.initials: U
authors.lastname: Kimura
authors.forename: Ayako
authors.initials: A
authors.lastname: Kinoshita
authors.forename: Aki
authors.initials: A
authors.lastname: Osawa
authors.forename: Osamu
authors.initials: O
authors.lastname: Negi
authors.forename: Kunitaka
authors.initials: K
authors.lastname: Haruna
authors.forename: Yuki
authors.initials: Y
authors.lastname: Mizuno
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Suga
mesh_terms: D000152:Acne Vulgaris / Q000150:complications*; D000328:Adult; D002921:Cicatrix / Q000209:etiology / Q000601:surgery*; D004548:Elasticity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007564:Japan; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D008297:Male; D012629:Sebum / Q000378:metabolism; D016037:Single-Blind Method; D012867:Skin / Q000378:metabolism*; D013997:Time Factors; D016896:Treatment Outcome; D014870:Water Loss, Insensible; D055815:Young Adult