Laser Revision of Scars
Author: Keyvan Nouri, MD; Chief Editor: Dirk M Elston, MD
Integumental injury initiates the cascade of wound-healing events. In most cases, wound healing results in restoration of skin that is smooth and normal in appearance. Despite its normal appearance, repaired skin achieves only 70-80% of its original tensile strength. This consequence of normal healing processes does not raise concern; rather, when healing deviates from its orderly pattern, scarring results. Scars are common complications of wound healing that affect millions of individuals. Although pigmentary and vascular alterations often are transient, textural changes caused by collagen disruption often are permanent.
The wound-healing process is divided into 3 major overlapping stages: inflammation, granulation tissue formation, and matrix remodeling. The initial stage is defined by a structured sequence involving inflammatory cells. This cascade is orchestrated by neutrophils. Subsequently, macrophages elaborate a variety of cytokines, which create an environment amenable to granulation tissue formation. Finally, fibroblasts migrate into the area, proliferate, and recapitulate ontogeny by depositing new collagen, first type III and later type I. Simultaneously, angiogenic factors released into the wound environment stimulate formation of new capillaries. A problem arises when this organized process is disrupted. An overzealous healing response may occur, creating a raised nodule of fibrotic tissue. Alternatively, deleted collagen is inadequately replaced and forms a pitted appearance resembling the surface of a golf ball. In either case, the scar often is a legacy of skewed wound healing.