Scar Revision 

The treatment of aesthetically displeasing scars of the head and neck is challenging at times, although not without options. While removing one scar without leaving another is not possible, replacing an unfavorable scar with a more camouflaged one, or rendering an existing scar less noticeable, is possible.

By the time scar revision patients present to a physician, they have exhausted every means at their disposal to disguise the scar. These attempts at concealing the scar typically involve the use of cosmetics, clothing, and hairstyle modifications. While various treatments exist, none is perfect, and the cornerstone of any scar revision is a thorough understanding of the patients' dissatisfaction with their appearance and their expectations following treatment. Patients must understand that the best result may require multiple treatments and that initially, little improvement may be noticeable relative to the preexisting deformity.

Other considerations of paramount importance when considering scar revision include (1) whether the scar is in a position that compromises function and (2) if any revision might result in decreased function. As with any skin defect, the quality and availability of surrounding tissue must be assessed.^{[1, 2]}

The Medscape Dermatology Surgery Resource Center and Aesthetic Medicine Resource Center may be helpful.

According to ancient Egyptian writing, scarification for aesthetic reasons dates back to 1700 BCE. Throughout history, different cultures have used scarring as a depiction of one's affiliation with a particular group, its exploits, or stature. In most cultures now however, scars on the head and neck are perceived as undesirable, and patients often present to their physician requesting revision to render their scars less noticeable.

In general, scar revision techniques are either operative or nonoperative in nature. More aesthetically pleasing scars are those that are less noticeable. Intuitively, this includes matching the surrounding skin in color, texture, distensibility, and elevation. The characteristics of scars are important relative to their surroundings. For example, scars often have fewer dermal appendages or lack them altogether. In areas of hair-bearing skin, a scar's lack of hair follicles is particularly noticeable. In other areas with sparse hair follicles, this is a desirable attribute of scars.

Patient characteristics also play a large factor in scarring, as does the quality of closure and the cleanliness of the wound. Patients at the extremes of age often scar to a greater degree. Young patients are more prone to excessive scar formation, while elderly persons are more prone to poor healing, owing to diminished fibroblast activity. Individuals with connective-tissue disease, diabetes mellitus, or vitamin deficiencies or those who return to activity too early may experience healing complications that result in greater scarring upon final closure.

Wounds that are poorly closed, undergo dehiscence, have necrosis of the skin edges, or have edges that are poorly approximated are more likely to heal with unsightly scarring. Likewise, wounds that become infected or undergo foreign body reactions to sutures more frequently yield poor cosmetic results. Proper screening of patients prior to surgery, proper nutrition, good technique, and conscientious wound care dramatically favor faster wound healing and more aesthetic results.

Before considering scar revision, the treating physician must have an understanding of wound healing and how scar tissue forms. Wound healing progresses in 3 phases: an inflammatory phase, a granulation phase, and the final, remodeling phase.

Inflammation is an immediate physiologic response to any injury to the body. In the skin, it serves the additional role of helping to contain and repel any organisms or foreign materials introduced into the tissues by a variety of traumas, including surgical incisions. The various mediators of inflammation are the first materials released in the wound, including activated complement, transforming growth factor-beta, circulating monocytes, tissue macrophages, neutrophils, platelets, clotting factors, and serum proteins, among others. Damaged collagen fibers promote platelet aggregation in the wound. Later, collagen provides the scaffold for wound healing as the major constituent of the extracellular matrix. This primary phase of wound healing typically lasts for 1-2 days.

The granulation or proliferative phase involves fibroblast proliferation within the wound bed. These cells are responsible for the production of the collagen extracellular matrix. Cytokines present in the wound bed at this time also promote the process of angiogenesis and the appearance of granulation tissue, a characteristic of the healing wound. Once collagen is laid down as an extracellular matrix and cells have grown on this scaffold, the wound enters the remodeling phase of wound healing.

The remodeling phase involves the reassortment of collagen fibers laid down in the preceding proliferative phase. Remodeling is the longest period of the wound healing process; it may continue for up to a year. However, 2-3 weeks is a more common interval for this final phase of wound healing. During this time, the net amount of collagen does not increase, but the formation of a more orderly arrangement of fibers helps to greatly increase the wound's tensile strength. When healed properly, the final wound strength reaches 70-80% of prewound strength.

The ideal scar is narrow and fills but does not eclipse the original volume of the wound bed. In fact, the wound often decreases in size upon healing due to contractile forces involved in scar formation. Occasionally, scar formation may be exuberant, as in the cases of hypertrophic scarring or keloid formation. Although discussed in detail in Keloid and Hypertrophic Scar, a brief mention of these unwelcome sequelae of wound healing is warranted.

Hypertrophic scars do not extend beyond the original boundaries of the wound laterally, but scar tissue may rise above the level of the surrounding skin. This commonly results in a very noticeable, irregularly contoured scar. A more extreme example of exuberant growth of scar tissue is the keloid. Keloid scars extend beyond the original borders of the wound, resulting in a raised and expanded scar relative to the original defect. These are often very noticeable, and they occur with increased frequency in persons with dark complexions. In both hypertrophic scars and keloids, components of the extracellular matrix are increased. Thus, while the number of fibroblasts present is normal, the cells present are apparently overactive in their wound healing response.

The indications for scar revision are often a matter of patient preference. Scars on the head and neck are distressing to most patients. However, certain aspects of a scar, such as the color or texture, may bother one patient more than another. Patients should be counseled that a scar-free revision is not realistic and that an optimal result is achieved only through cooperation between patient and physician.

Cigarette smoking, nonsteroidal anti-inflammatory drugs, vitamin E, and isotretinoin should be stopped at the appropriate time prior to revision. Noninvasive or minimally invasive measures such as microdermabrasion and intralesional steroid injection can be performed as early as 3 weeks after revision of the scar, but many practitioners prefer to wait 6 weeks. When undertaking a revision, subtle problems should be treated conservatively first, before more aggressive interventions are used. Patients should be informed that the final maturation of the scar may take up to a year after revision. Above all, stress to the patient that scar revision merely replaces one scar with another in an attempt to improve the aesthetics of the area.

Complete restoration to the preinjury state is not possible under any circumstances, but the revised scar may be less detectable. A patient with realistic expectations is more likely to be satisfied with the final results of the revision procedures than a patient with unrealistic expectations.