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 (CO(2) FS) have not been established.

Objective: To compare the efficacy and safety of low-fluence, high-density with high-fluence, low-density treatment with CO(2) 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 CO(2) FS with a fluence of 70 mJ and a density of 150 spots/cm(2) ; the other half was treated with a fluence of 30 mJ and a density of 250 spots/cm(2) .

Results: Follow-up results 3 months after a single low-fluence, high-density treatment with CO(2) FS showed that four of 10 participants had clinical improvement of 51% to 75% from baseline. After the high-fluence, low-density CO(2) 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 CO(2) FS.