Aesthetic Plast Surg. 2026 May 18. doi: 10.1007/s00266-026-05907-y. Online ahead of print.
ABSTRACT
OBJECTIVE: To assess the impact of CO2 fractional laser intervention at various time points within one month post-surgery on scar formation, thereby guiding clinicians in optimizing the timing of treatment.
METHODS: Six New Zealand white rabbits were used in this study. Six surgical incisions were made on the ventral side of each rabbit’s ear and randomly divided into six groups: Group A (non-laser intervention group), Group B (the day of surgery laser intervention group), Group C (1 week post-surgery laser intervention group), Group D (2 weeks post-surgery laser intervention group), Group E (3 weeks post-surgery laser intervention group), Group F (4 weeks post-surgery laser intervention group). At week 7 post-surgery, Scar Cosmesis Assessment and Rating (SCAR) scores were recorded. Hematoxylin and eosin (HE) staining was employed to measure dermal thickness, while Masson staining was utilized to determine the collagen volume fraction. Additionally, microvascular density was evaluated via CD31 immunohistochemistry. One-way analysis of variance (ANOVA) was conducted to assess overall differences among the groups. Where significant differences were found, the least significant difference (LSD) post hoc test was employed for pairwise comparisons. Statistical significance was determined at a threshold of P< 0.05.
RESULTS: At week 7 post-surgery, macroscopic observation revealed that Group A (non-laser intervention group) exhibited the most pronounced linear scars. In contrast, Groups B to F, which underwent laser intervention, displayed only partial linear scars. The SCAR scores, dermal thickness, collagen volume fraction, and microvascular density in Group A were all significantly higher than those in the laser intervention groups (Groups B-F) (P < 0.05). However, no statistically significant differences were observed among the laser intervention groups (Groups B-F) for any of these parameters (P > 0.05).
CONCLUSIONS: CO2 fractional laser intervention at five different time points-the day of surgery, and at 1, 2, 3, and 4 weeks post-surgery-significantly reduces scar formation on rabbit ear surgical incisions. However, earlier laser intervention for postoperative scars within one month does not yield superior outcomes.
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PMID:42151609 | DOI:10.1007/s00266-026-05907-y
