Background: Since Langer's first foray into studying cutaneous lines, although people have studied skin lines across the body, there has not been a study that elucidates changes to skin structure of elastin and collagen at different load levels. This study set out to look at whether incisional lines and excisional lines have different biodynamics and have to be considered differently.Materials and Methods: For this study, we used a two-photon microscopic camera using optimal wavelengths to detect collagen and elastin. Measurements were taken in 5 patients at the center of the excisional wound (high-load) and at the ends of the wound (tapered end of the ellipse) where effectively the wound is an incisional wound.Results: Wounds were observed after they were surgically closed. When incisional wounds were observed, where there was minimal tension (<1.5N force) we found that, in each case, elastin stretched and collagen buckled, revealing mostly elastin. Where larger defects were created after excisions (as in the figure where a skin cancer had been removed, where forces to close wounds were typically greater than 2N), we noted that the image revealed mostly collagen, suggesting that the reverse had occurred (i.e. collagen stretched and elastin buckled).
Conclusion:This difference between tension loads on skin and the interplay between collagen and elastin has never before been elucidated for incisional and excisional wounds, and in the author's view has great research interest for a cutaneous surgeon seeking to identify the best skin lines to utilize to minimize scarring.