Lower-Fluence, Higher-Density versus Higher-Fluence, Lower-Density Treatment with a 10,600-nm Carbon Dioxide Fractional Laser System: A Split-Face, Evaluator-Blinded Study

BACKGROUND Adequate laser settings in the treatment of scars using a carbon dioxide fractional laser system (CO2 FS) have not been established. OBJECTIVE To compare the efficacy and safety of low-fluence, high-density with high-fluence, low-density treatment with CO2 FS on acne scars and enlarged pores. METHODS Ten patients with mild to severe atrophic acne scars and enlarged pores were enrolled. Half of each subject's face was treated with a single session of CO2 FS with a fluence of 70 mJ and a density of 150 spots/cm2; the other half was treated with a fluence of 30 mJ and a density of 250 spots/cm2. RESULTS Follow-up results 3 months after a single low-fluence, high-density treatment with CO2 FS showed that four of 10 participants had clinical improvement of 51% to 75% from baseline. After the high-fluence, low-density CO2 FS treatment, five of 10 patients demonstrated marked clinical improvements of more than 76%. CONCLUSION Higher-energy, lower-density laser settings seem to be more effective than lower-energy, higher-density settings for acne scars and enlarged pores, although our results do not constitute a conclusive comparison of the two different modes of CO2 FS. The authors have indicated no significant interest with commercial supporters.