title: Laser skin resurfacing of the face with a combined CO2/Er:YAG laser.
abstract: BACKGROUND
  A combined, dual-wavelength CO2/Er:YAG laser system having the ability to deliver both clean ablation of skin with the erbium wavelength and a simultaneous deeper penetrating subablative thermal pulse of CO2 was developed for full-face resurfacing. The CO2 component can be pulsed from 1 to 100 msec at a power of 1-10 W with the Er:YAG component pulsed at 350 microsec at 1.7 J/cm2 through either a computer pattern generator with 3 mm diameter spot size or through a noncollimated spot ranging from 0.2 to 8 mm in diameter. Our previous study using this laser on the neck using a 4-8 mm diameter spot with Er:YAG fluence at 1.7 J and the CO2 at 5 W with a 50 msec pulse at a frequency of 10 Hz showed a higher degree of overall patient satisfaction, as well as improvement in skin texture and skin color, compared to patients treated with an Er:YAG laser alone.
  
  
  OBJECTIVE
  This study evaluated the CO2/Er:YAG laser treatment modality in facial resurfacing.
  
  
  METHODS
  Ten patients were treated with four passes at 1.7 J with a 4 mm diameter spot and the CO2 at 5 W with a 50-msec pulse at a frequency of 10 Hz. Photoaging scores as well as thermal damage and new collagen formation were compared immediately before and after treatment as well as at 2 weeks and 3 months postoperatively.
  
  
  RESULTS
  The average pretreatment periorbital score was 6.2 The average posttreatment periorbital scores were 4.2 (P =.0239) at 2 weeks postoperatively (32% improvement) and 3.8 (P =.0028) at 3 months postoperatively (38% improvement). The average pretreatment perioral score was 5.9. The average posttreatment perioral scores were 3.0 (P =.0001) at 2 weeks postoperatively (49% improvement) and 3.3 (P =.0009) at 3 months postoperatively (44% improvement). The average pretreatment cheek score was 4.7. The average posttreatment cheek scores were 2.7 (P =.0066) at 2 weeks postoperatively (43% improvement) and 3.8 (P =. 0152) at 3 months postoperatively (36% improvement). The average pretreatment forehead score was 4.7. The average posttreatment forehead scores were 3.8 (P =.0340) at 2 weeks postoperatively (33% improvement) and 3.6 (P =.0147) at 3 months postoperatively (37% improvement). The average depth of collagen measured in the dermis pretreatment was 29 microm. The average depth of collagen 3 months posttreatment was 54 microm. This is an average increase of 25 microm or an 86% increase in collagen (P =.006). The average thermal damage immediately after treatment was 20 microm.
  
  
  CONCLUSIONS
  The CO2/Er:YAG laser utilized with four passes at the above-mentioned parameters results in a similar degree of improvement as other forms of laser resurfacing with high-energy, short-pulsed CO2 lasers.
authors.affiliation: Dermatology/Cosmetic Laser Associates of San Diego County, Inc., La Jolla, California 92037, USA. mgderm@aol.com
authors.forename: M P
authors.initials: MP
authors.lastname: Goldman
authors.forename: N
authors.initials: N
authors.lastname: Marchell
authors.forename: R E
authors.initials: RE
authors.lastname: Fitzpatrick
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001706:Biopsy; D062109:Dermatologic Surgical Procedures; D005069:Evaluation Studies as Topic; D005145:Face / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D053685:Laser Therapy / Q000295:instrumentation / Q000379:methods*; D008875:Middle Aged; D011300:Preoperative Care; D011446:Prospective Studies; D012867:Skin / Q000473:pathology; D015595:Skin Aging / Q000473:pathology; D013997:Time Factors