Safety and Tolerability of Fractional CO ₂ Lasers for Facial Rejuvenation Across Fitzpatrick Skin Phototypes I– IV : Retrospective Cohort Study

BACKGROUND: laser systems include pulse modes such as HighPulse (HP), which deliver high energy over a shortened dwell time, reducing the duration of energy delivery per microbeam with the aim of limiting thermal diffusion beyond the ablation zone. METHODS: laser using HP mode for facial rejuvenation. Pain scores and adverse events were recorded, stratified by skin type and anesthetic use. RESULTS: Mean pain score was 4.8, with no statistically significant difference between patients who received topical anesthetic (LMX4) and those who did not. Pain scores did not differ significantly across skin phototypes I-IV. Erythema occurred in 50% of patients and edema in 24%, all of which were transient. No cases of blistering, post-inflammatory hyperpigmentation, or scarring were documented in routine clinical records, although the true incidence may be underestimated. Erythema rates did not differ significantly by anesthetic use. CONCLUSIONS: In this preliminary cohort, the HP fractional laser was associated with transient short-term adverse effects and no documented pigmentary complications among patients with Fitzpatrick skin types I-IV. These findings are descriptive and are not generalizable to Fitzpatrick phototypes V-VI, which were not represented.