Clinical and Histological Analysis after Laser Treatment in Hypertrophic Scar

ABSTRACT

PURPOSE: A hypertrophic scar following a burn injury is caused by the excessive deposit of collagen resulting in an exaggerated wound healing response. The aim of this study was to investigate the clinical and histological analysis after laser treatment in hypertrophic scar. METHODS: Three patients underwent a hypertrophic scar contrcture release and skin graft. The Modified Vancouver Scar Scale (MVSS) is commonly used to evaluate scars. It was composed of pliability, height, vascularity and pigmentation. Thickness was measured by an ultrasound. Pain and itching over the scar were recorded by using the Verbal Numerical Rating Scale (VNRS). All biopsies were taken from scar tissue and normal tissue for grafting area in the operation room. Epidermis and monocytes around vessels, collagen fiber, elastic fiber and mast cell of scaring dermis part observed histologically. RESULTS: On the basis of microscopic findings in patient 3, there are two patterns. The upper part of dermis shows thickened, glassy, eosinophilic collagen bundles which is similar to that of keloid formation. The lower part of dermis shows hypercellular collagen fibers, which is similar to that of regular hypertrophic scar pattern. Probably this patient may have a tendency of keloid formation or secondary change of Laser therapy. Clinical correlation is suggested. CONCLUSION: The laser has the improvement of hypertrophic scaring but can make histological changes due to many procedures. We should be aware of the side effects of the laser.