Polarization enhanced wide-field imaging for evaluating dermal changes caused by non-ablative fractional laser treatment

Background and Objective Laser non‐ablative fractional treatment (NAFT) is an important part of armamentarium of modern dermatology. Recently, such treatments have become available in at‐home setting due to advent of self‐application NAFT devices. Safety and clinical efficacy of NAFT are well established in multiple studies. Less information is available on morphological and functional changes in tissue occurring as a result of NAFT. Polarization‐enhanced multispectral wide‐field imaging device allows for in vivo real time visualization of dermal structures. The objective of this study is to use this imaging modality to monitor early effects of the home‐use NAFT on collagen networks. Materials and Methods Eight subjects (skin types I–III) used a commercially available NAFT device (wavelength 1410 nm, energy per pulse up to 15 mJ) to treat peri‐orbital wrinkles in standard recommended mode, that is daily, for a period of two weeks. In each session, subjects applied a pre‐treatment gel to the peri‐orbital areas and then used the device, delivering 8–10 applications to each side of the face without overlap. Subjects were asked to use the highest device setting. Cross‐polarized 440 nm wide‐field images were acquired from peri‐orbital areas before and two weeks after the onset of the treatment regimen. Wide‐field images were normalized and thresholded to a level of 40% brightness to emphasize collagen structure. Collagen content was quantitatively determined from thresholded collagen images. Improvement in collagen content at two weeks of daily treatments was assessed. Results Eight subjects (age 24–53 years) completed the study. Cross‐polarized 440 nm wide‐field images clearly delineated collagen networks. Quantitative assessment of collagen images revealed statistically significant (P