Scars

Scars (cicatrix; scar; ICD-10-GM L90.5: scars and fibrosis of the skin) are so-called replacement tissues that the body forms to close wounds. They represent the final state of healing. Mustoe scar classification (modified from):

• Mature scar – light, flat and soft scar at the skin level or slightly below the skin level.
• Immature scar – scarring not yet completed; it shows a reddish to brown or blue-reddish scar, which is sometimes itchy and rarely slightly painful; is minimally elevated; it presents as a papule (thickening of the skin) or plaque (areal or plate-like substance proliferation of the skin)
• Hypertrophic scar
  • Linear hypertrophic scar – strand-like bulge with an irregular surface; a red, raised, sometimes itchy and slightly painful scar appears; loses color over time; it is possible for a hypertrophic scar to regress on its own.Growth approximately 3-6 months, then regression (regression) over 2 years.
  • Areal hypertrophic scar (> 0.5 cm) – red, irregularly raised scar, also nodular; usually significant itching and touch pain, occasionally spontaneous pain; initial wound edges are respected; possibly also coarse papules, plaque or nodules (origin: areal injuries such as burns and burns).
• Keloid – this occurs as excessive scarring when the body produces too much collagen in the wound area. The tendency to excessive scarring is a genetic predisposition. However, it not infrequently occurs only in certain regions of the body. For example, the body may form excessive scars on the trunk, but “normal” scars that are barely visible on the arms and legs.
  • Small keloid (< 0.5 cm) – red, irregular surface level, also nodular, always itching and pain on touch (highly sensitive); possibly also spontaneous pain; initial wound edges are exceeded
  • Large keloid (> 0.5 cm) – red, irregular surface level, plaque-like, also nodular and irregularly bumpy, always itching and touch pain (highly sensitive); spontaneous pain (rel. frequent)Continuous growth > 1 year. Initial wound edges are exceeded
• Atrophic scar – pale, often multiple skin depressions, such as may be left behind in severe acne, among other conditions, including.
  • Narrow deep (ice pick) depressions or.
  • Wide cup-shaped (rolling) depressions or
  • Wide, like punched out (boxcar) depressions

Symptoms – Complaints

Scar classification according to Mustoe describes at the same time the clinical picture of a scar in its possible states. Depending on the type of scar (see below scar classification), scars can cause itching, tightness and pain, possibly also movement restrictions.

Pathogenesis (disease development) – etiology (causes)

Scars occur after injuries, burns, inflammation – for example, due to acne (e.g. acne vulgaris) – after surgery or similar. The process of wound healing is called scarring and cicatrization. Wound healing proceeds in the following phases:

• Exudative phase (hemostasis (hemostasis)) – in the first hours or until the 1st day after the injury.
  • Immigration and aggregation (clustering of individual cells into associations) of platelets (blood clots).
  • Release of cytokines (proteins that play an important role in the immune system): hemostasis.
  • Exudation (secretions) of fibrin (Latin : fibra ‘faseŕ; “glue” of blood clotting) and coagulated (clotted) blood fills the wound gap. Scab is formed, which protects the wound externally against the penetration of germs.
• Inflammatory phase (inflammatory phase) – 1st to 3rd day after injury.
  • Catabolic autolysis: macrophages (“scavenger cells”) eliminate blood coagulum (blood clots) from wound tissue.
  • Fibrin degradation
  • Inflammatory response and signs
  • Infection defense
• Proliferative phase (granulation phase) – 4th to 7th day after injury.
  • Formation of granulation tissue by mediators, angioblasts, fibroblasts (connective tissue cells), myofibroblasts.
  • Regeneration of basement membrane zone and epithelium (superficial cell boundary layer).
• Reparative phase (scarring phase) – 8th to 12th day after injury.
  • Formation of collagen fibers
  • Wound contraction: tensile strength increases
  • Epithelialization (the wound grows with epithelial cells to).
• Differentiation phase – from 2 to 3 weeks or up to 1 year.
  • Remodeling (remodeling processes) specific tissue: intact scar-free skinor.
  • Granulation tissue is remodeled into stress-resistant connective tissue; the wound contracts and becomes tear-resistant; a scar is formed – scars are initially well supplied with blood and appear bright red; gradually, the blood vessels are broken down and the scar appears less and less red until it finally fades.

Superficial abrasions rarely leave scars. Particularly at risk for unsightly scarring are the chest and shoulder. Keloids often run in families. Furthermore, dark-skinned skin types have an increased risk of keloid formation.The deeper a wound is, the greater the likelihood of scarring.Scars are usually reddened at the beginning and later fade.What remains are usually white scars. This is due to the fact that scars are not able to form pigments like the rest of the skin.

Diagnostics

Scars are detected by visual diagnosis.

Prevention

Use of scar ointments: these contain silicones or enzymatically active substances as active ingredients to counteract hypertrophic scarring (allantoin, heparin, onion extract).

Therapy

Scars can be removed in a variety of ways:

• First, it is possible to inject individual sunken scars using fat or hyaluronic acid to bring them back in line with the skin level.
• Not all scars can be injected under, protruding, i.e. hypertrophic scars can not be relined, they must be cut out, removed by milling or treated by other methods.
• If the scars are extensive, for example, distributed throughout the face, more extensive methods are used.
• Surgical methods are: Scar correction, dermabrasion.
• Cryopeeling (cold peeling), dermabrasion treatment or chemical peels can be used to treat not only individual scars, but also larger areas of skin covered with scars.
• Hypertrophic scars and keloids.
  • Injection therapy with triamcinolone and verapamil (calcium antagonist) (1:1 mixture (triamcinolone: 49 mg/ml); verapamil: 2.5 mg/ml)) showed a good result after a total of three injections:
    • In hypertrophic scars, patient and observer scar assessment scale (POSAS) scores improved significantly: baseline (70.59) and time points 3-4 months (43.33), 4-6 months (48.80), and after more than 12 months (46.83)
    • For keloids, POSAS scores significantly reduced compared with baseline (67.77) (3-4 months: 46.57; 4-6 months: 48.5; after more than twelve months: 39.0)
  • Intralesional injection (“inside the damage”) of triamcinolone plus hyaluronic acid for keloids showed good efficacy with a low spectrum of side effects; intralesional radiofrequency therapy plus triamcinolone was similarly effective.
  • The combination of topical (external application) clobetasol propionate and a silicone dressing showed the same efficacy as intralesional injection of triamcinolone.
• Removal of the keloid is possible by cryotherapy (cold therapy).
• Laser therapy
  • Scars can be removed with a CO2 laser, erbium Yag laser (Er:YAG laser), or argon laser, among others.
    • Red scars: Blood flow reduction of the top layer of skin (dye laser; vascular laser).
    • Brown scars: ruby laser, neodymium Yag laser or Fraxel laser.
  • Hypertrophic scars and keloids can be additionally treated by dye laser. The scar tissue is vaporized by the energy of the laser beams. Note: Monotherapy for keloids with ablative lasers (Er:YAG and CO2 laser systems) is not very successful.
  • Excess scar tissue can also be vaporized with a CO2 laser. However, due to the predisposed tendency, there is a risk that overshooting scar tissue will form again after treatment.

Depending on how deep the scar is in the skin, it is not always possible to completely remove a scar.Nevertheless, the appearance and therefore the aesthetics can be significantly improved in most cases.There is no guarantee that a scar correction will last.