Affiliation:
1. Laser Dermatology Consultation, Division of Dermatology and Venereology Geneva University Hospitals Geneva Switzerland
2. Pediatric Dermatology Unit, Departments of Dermatology & Venereology, University Hospital Lausanne University of Lausanne Lausanne Switzerland
3. Dermato‐Oncology Unit, Division of Dermatology and Venereology Geneva University Hospitals Geneva Switzerland
Abstract
ABSTRACTBackgroundThe advent of ablative fractional photothermolysis has revolutionized laser dermatology by providing a method to produce well‐standardized, precise, and repeatable microscopic lesions. These wounds typically heal within 1–3 weeks, depending on the body site, with a minimal risk of permanent scarring. This positions ablative fractional photothermolysis as an exemplary in vivo model for studying the skin's wound healing processes.ObjectivesThis study aims to evaluate and compare the effectiveness of two noninvasive imaging techniques, reflectance confocal microscopy (RCM) and line‐field confocal optical coherence tomography (LC‐OCT), in assessing skin wound healing following microscopic injuries induced by ablative fractional photothermolysis.MethodsThe forearms of participating volunteers were treated and ablated with a CO2‐Laser in a fractional pattern using varying power settings (2.5–10 mJ/MTZ). In vivo RCM and LC‐OCT images were obtained at predefined time intervals post‐laser treatment, ranging from 6 h to 14 days.ResultsVertical visualization of the lesions through both imaging modalities revealed a healing process characterized by the upward and outward movement of microscopic epidermal necrotic debris, thereby reducing the depth of the injury while forming an external crust. LC‐OCT imaging demonstrated more comprehensive results with fewer movement artifacts. Conversely, horizontal visualization with both techniques highlighted a gathering of keratinocytes around the wounds, indicating the initiation of the regenerative process. RCM provided superior image clarity in this horizontal plane.ConclusionsRCM and LC‐OCT offer valuable and complementary noninvasive alternatives to conventional biopsy methods for the assessment and characterization of the skin's wound healing process post‐ablative fractional photothermolysis. These findings underscore the potential of such imaging techniques in enhancing our understanding of the wound healing process.Trial RegistrationClinicalTrials.gov identifier: NCT05614557.