Scar Revision, Keloids, and Camouflage

Serial Excision

Wide scars, birthmarks, and skin grafts with poor match to surrounding tissues can all be candidates for serial excisions. In some ways, this is a variant of tissue expansion, in that scarred skin is excised and adjacent normal skin brought into the defect area. Like tissue expansion, this technique relies on the skin's biologic creep (ability to stretch over time) and is limited by the given amount of stretch attainable during each excision. Typically, older patients and those with increased skin laxity will require fewer excisions than younger patients with increased skin tone. As with all techniques of scar revision, the patient must be well informed as to the proposed number of excisions and must understand that serial excision can require months to years to complete.

Tissue Expansion

When treating larger scars, the best camouflage is afforded when abundant amounts of similar-appearing tissue can be brought into the repair. Tissue expansion can be a powerful tool to help create excess amounts of surrounding tissue. Tissue expanders are available in a variety of shapes and sizes. Studies on the gain of surface area afforded by the three most commonly shaped expanders have determined that rectangular expanders provide the greatest expansion at 38%, crescent-shaped expanders provide 32%, and round expanders provide only 25%. As a general rule, the base of an expander should be approximately 2.5 to 3 times as large as the area to be reconstructed.

The effects of tissue expansion on skin have been debated. The currently accepted understanding regarding tissue layer expansion is that (1) the epidermis is thickened, (2) melanin production increases, (3) mitotic activity increases, (4) dermis thins (30% to 50%), (5) collagen synthesis is enhanced, (6) hair follicle number remains unchanged, (7) hair density decreases, (8) muscle thins and can atrophy, and (9) blood vessels proliferate. Interestingly, epidermal changes and increased melanin production seen during expansion resolve a few months after surgery.

Implantation of the expanders must take into account the neurovascular supply and final positioning of the skin to be transferred. Expansion can proceed until the skin blanches or the patient complains of discomfort. Intervals between injections can be from 4 to 14 days, ideally two to three times per week.

A critical point of understanding for the clinician is the temporary psychological toll that is placed on the patient undergoing expansion. Tissue expanders can cause impressive disfigurement of the head and neck, which naturally results in significant emotional stress to the patient ( Fig. 18.5A ). It is essential to remind the patient that the disfigurement is temporary and that the final reconstruction will warrant the time spent dealing with the expansion devices (see Fig. 18.5B ).

Z-plasty

The Z-plasty is one of the oldest and simplest techniques for scar irregularization, with the additional benefits of scar reorientation and adjustable elongation. A “classic” Z-plasty involves the transposition of equilateral 60-degree triangles ( Fig. 18.6 ). When these triangular flaps are transposed and closed, the original direction of the scar is rotated and the scar is lengthened by 75%. When lesser amounts of lengthening are required, a 30-degree or 45-degree Z-plasty can be used to lengthen the scar by 25% or 50%, respectively. Longer scars may benefit from multiple Z-plasties. This can be particularly helpful when correcting scar contractures along anatomic concavities. Consecutive Z-plasties allow for the redistribution of forces more evenly along the entire length of the scar and help camouflage the scar into the surrounding RSTLs ( Fig. 18.7 ).

W-Plasty and Geometric Broken Line Closure

Both W-plasty and geometric broken line closure (GBLC) are useful irregularization techniques that often use shorter limbs compared with Z-plasty and do not create lengthening of the scar. The general concept is the same—that the human eye will have a harder time following an irregular line versus a straight line. The key difference is that W-plasty creates regular irregularization and GBLC creates irregular irregularization of the final scar line. The technique begins with the marking out of a series of consecutive shapes. The arms should be between 5 and 7 mm in length, and ideally at least one arm of a given shape is in parallel with the RSTLs ( Figs. 18.8 and 18.9 ). Although these segments may look long when marked on the patient's face, due to the natural skin contraction following incision, 5 mm turns out to be the shortest segment one would want to use. After excision previously stated principles of wide undermining, low tension closure, and delicate skin edge suturing are all followed. These wounds are also amenable to postoperative dermabrasion to further camouflage the wound.