How Does Scarring Occur?
Scar formation is a natural part of the healing process after injury. Various factors influence how your skin scars. For example, the depth and size of the wound or incision and the location of the injury will affect the appearance of the resulting scar. Many other factors, including age, heredity, gender and ethnicity, will affect how skin reacts.
What is a keloid?
A keloid scar is a raised or thickened scar that tends to grow rapidly above the surface of the skin at the site of an injury. It may appear as having a smooth top and a pink, red or purple color. Keloid scars tend to be irregularly shaped and may become progressively enlarged. Unlike other forms of scarring, keloid scars do not resolve or get softer over time. Keloid scars can occur from acne, burns, chickenpox, ear piercings, body piercings, minor scratches, skin incisions, traumatic wounds, and vaccination sites.
What is the difference between a keloid and a hypertrophic scar?
Hypertrophic scars result after the skin has been injured and the healing process usually leaves a flat or level scar. If the scar is thickened or raised, but confined to the margin of the wound, it may be considered to be hypertrophic. Hypertrophic scars tend to be red and may subside on their own over 6-12 months, or with the aid of intralesional steroid injection therapy.
Keloid scars may start at any time after the skin has been injured, and extend beyond the wound site. This tendency to continue to grow is the main difference between keloid and hypertrophic scars. Keloids typically appear following surgery or injury, but they can also appear spontaneously or as a result of inflammation, such as acne, burns or insect bites.
What are the signs of a keloid scar?
Keloids are raised and may appear shiny and dome-shaped, ranging in color from pink to red or purple. Some keloids become quite large and unsightly and can be painful. These scars are also commonly itchy, tender and tight and can be unsightly and a cause of severe disfigurement and social embarrassment.
What causes keloid scars?
The causes of keloid scars can be varied. Doctors do not understand the precise reasons why some people are more prone to developing keloid scars, and cannot predict who is most likely to form them. It is possible to develop a keloid scar in one earlobe after piercing and not in the other.
Who is most susceptible to keloids?
Keloid scars are equally common in women and men, and less common in children and the elderly. Keloid scars also tend to be more common in people ages 10 – 20, and the tendency to form keloid scars often runs in families.
Although people with darker skin types, predominantly African Americans, Asians and Hispanics, are more likely to develop them, keloid scars can occur in people of all skin types.
In which areas do keloids tend to appear?
Keloids develop most often on the chest, back, shoulders, and around the earlobes. They are less common on the face, but can sometimes appear on the jawline.
What are the treatments for keloids?
Intralesional Steroid Injections: Steroid injections may be used to help flatten keloids; however, they can also make the flattened keloid redder by stimulating the formation of more superficial blood vessels. Over use of steroid injections may also lead to skin atrophy or depressions.
Surgery: Excising a keloid scar can trigger the formation of a similar or even larger keloid scar. Applying pressure dressings to a wound site after excising the keloid can help in some cases.
Laser Therapy: Pulsed-dye lasers can be effective at softening keloids and reducing redness. Several treatment sessions may be needed.
Silicone Sheets: Silicone sheets, gels, patches and creams are commonly applied to scars with very variable results.
Interferons: Interferons are proteins produced by the immune systems to fight off viruses and bacteria. Injections of interferon have been shown to help reduce the size of keloid scars, at least temporarily. Applying topical Imiquimod has also been used to stimulate the body to produce interferon.
Fluorouracil: Injections of Fluorouracil, a chemotherapy agent, have also been used with and without steroid injections to treat keloid scars.
Radiation: Some doctors have used radiation therapy to shrink keloid scars.