Introduction: Laser resurfacing with the 950 microsec pulsed CO2 laser has been proven to be efficacious in improving photodamaged skin and acne scarring. Unfortunately, prolonged erythema and delayed wound healing are common adverse sequelae, which require intensive patient education and intervention. These adverse effects may be due to the degree of nonspecific thermal damage present after resurfacing with the CO2 laser. Since erbium: YAG (Er:YAG) laser vaporization leaves far less thermal damage, it is hypothesized that its use after CO2 laser resurfacing will decrease the extent of nonspecific damage and result in improved wound healing.
Methods: Ten patients were randomized to receive laser resurfacing of one-half of the face with the 950 Msec pulsed CO2 laser with 3 passes at 300 mJ, utilizing the computer pattern generator (CPG) at settings of 596, 595, 584, and the other half of the face (randomly chosen) resurfaced with the 950 Msec pulsed CO2 laser 2 passes with the CPG at 300 mJ at settings of 596 and 595, followed by 2 passes with the Er:YAG laser (Derma-20 or Derma-K, ESC Medical Systems, Inc., Needham, MA) with a 4 mm diameter spot size at 1.7 J (approximately 14 J/cm2). Patients were evaluated in a "blinded" manner clinically and histologically before resurfacing, immediately after resurfacing, 2 to 3 days postoperatively, 1 week postoperatively, and, 4 to 8 weeks postoperatively.
Results: There was slightly less inflammation with the CO2/Er:YAG-treated patients. The epidermis re-formed 1 to 2 days faster with combination (UPCO2)/Er:YAG treatment than with UPCO2 laser treatment alone. In 7 of 10 patients, Er:YAG erythema resolved within 2-3 weeks with CO2 x 3 erythema persisting at the 8-week follow-up period in all patients. Three of 10 patients had no difference in the degree of erythema between the 2 treatment areas. Clinical findings correlated with histologic findings of vascularity. There was no difference in the extent or time of edema between techniques. The usual demarcation line between cheek and neck at the mandibular angle was less apparent when the UPCO2/Er:YAG combination was used. Two of 10 patients noted quicker healing with the combination laser technique.
Conclusion: Treating a patient with the Er:YAG laser after treatment with the UPCO2 laser results in a decreased incidence of adverse sequelae without a noticeable difference in the degree of wrinkle improvement.