Brief Anatomy
The skin varies considerably in thickness and consistency. An intricate feature of the skin are the so-called relaxed skin tension lines. These lines develop as a result of the activity of underlying muscles and are related to the visible lines that run, for example, across the forehead. When a cut or incision runs across the skin tension lines, the wound is distracted and distorted every time the underlying muscle contracts. The negative effects of muscle activity are more pronounced the more the scar runs at an angle relative to the relaxed skin tension lines. In contrast, wounds that are aligned parallel with the relaxed skin tension lines are called favorable and tend to heal with better cosmetic results.
An effective method to improve healing and reduce scar formation is by injecting the musculature adjacent to a wound with botulinum toxin. Thus the musculature is paralyzed for approximately 2 months and favorable healing can take place before muscle activity recovers.
Preop Evaluation
Most aspects of pre-, intra-, and postoperative care vary considerably among surgeons. The suggestions given herein represent the author’s preferences at the University of Regensburg (Germany) and have proven successful over time. However, these suggestions are not meant to be dogmatic or to imply that different preferences are less effectual. Scars may restrict certain functions, such as nasal breathing or eye closure. A contracted scar may also limit the mobility of the neck and other facial areas. And scars are frequently visible because of discoloration, width, fullness, depression and other features.
Each of these aspects may require individualized treatment, and the sequence and timing of the required procedures should be discussed in detail with the patient. Choosing the right time for scar revision is important, since scars are frequently not treated until they have matured for an extended period of time. It may take time until all treatments are complete, healing has taken place and the desired result is achieved.
Treatment
The best scar treatment is to prevent the formation of a scar in the first place. A number of measures can be employed to optimize healing after an injury or surgery. As stated above, the activity of surrounding muscles may negatively affect healing. Injection of botulinum toxin has been shown to immobilize wounds during the healing phase. This leads to more favorable scarring. Especially wounds in animated areas, such as the face and neck, frequently promise to heal better if botulinum toxin is injected. Therefore facial wounds resulting from surgery or an accident should be evaluated for prophylactic botulinum toxin injection.
If a patient is prone to forming particularly wide, so called hypertrophic scars, an injection of a steroid into the scar during the first weeks of healing may be beneficial. These injections may be repeated every week or two. Once a scar exists, there are a number of treatment options. An uneven or elevated scar may be polished with a laser or a diamond burr. A wide scar may be excised and replaced by a finer scar. Since straight scars are more visible than irregular ones, scar excision may be performed according to the “broken line” technique: A number of angles and shapes are incorporated into the new excision line and make the new scar more cosmetic. If a scar is very wide, as is the case for burn scars, it may be necessary to remove it in pieces with serial excisions. This may be combined with skin expansion: When there is not enough surrounding tissue available to cover the previous scar, a balloon is temporarily inserted to stretch the adjacent skin prior to scar revision.
For more complex and larger scars, advanced surgical techniques may be required for correction. These include various flaps.
Post Op Instructions
During the early healing phase, the wound is covered with an occlusive dressing or an ointment to keep the wound moist. Sutures are typically removed after 5 to 7 days, and sun exposure is strictly limited for at least 6 months. Continuity of care is especially important in scar revision treatment. Intermittent postoperative visits with the same surgeon are scheduled to evaluate healing and perform additional treatments as required.
Literature References
Gassner HG, Brissett AE, Otley CC, Boahene DK, Boggust AJ, Weaver AL, Sherris DA.
Botulinum toxin to improve facial wound healing: A prospective, blinded, placebo-controlled study.
Mayo Clin Proc. 2006 Aug;81(8):1023-8.
Gassner HG, Sherris DA.
Chemoimmobilization: improving predictability in the treatment of facial scars.
Plast Reconstr Surg. 2003 Oct;112(5):1464-6
Sherris DA, Gassner HG
Botulinum toxin to minimize facial scarring.
Facial Plast Surg. 2002 Feb;18(1):35-9.