Scar

From ArticleWorld

A scar is the end result of the biological process that repairs the skin and some of its deeper layers. It is tissue that is similar in appearance but microscopically different from normal skin. It often has no hair follicles or sweat glands and is less resistant to UV radiation. There are fewer melanocytes (pigment cells) in scar tissue than in surrounding skin.

Formation

Scars occur whenever the deeper dermis layer of the skin is damaged and are the result of a wound healing process that begins with the cleansing of the wound by macrophages and other phagocytes and ends when epidermis covers the wounded area. Layers of collagen are laid down to bridge the gap between the normal edges of the wound. Small capillaries grow within the scar and give it an initial reddish color that fades with time. Most mature scars are flat and paler than the surrounding tissue. They are also less elastic than normal skin.

Abnormal scarring

Generally, the deeper the scar and the wider the gap between healthy tissues, the more visible a scar becomes. This is why wounds are often sutured. Sutured wounds scar less when the healthy tissue is pulled in close proximity to the original state. Some people form an excess of collagen whenever a wound heals, leading to a red, raised scar. This is called a hypertrophic scar. This type of scar gradually improves in appearance over time.

Some people form a more serious type of scar known as a keloid. Keloid scars are also produced by an excess of collagen but often grow in a tumor-like fashion beyond the margins of the original wound. Younger people and those with dark skin are more likely to form keloid scars. There seems to be a genetic predisposition toward getting them.

Other abnormal scars appear as a sunken area of tissue without the normal supporting structures of normal skin. Stretch marks are a form of scar that occurs when the skin overstretches during rapid weight gain or adolescence. This type of scar appears less obvious over time.

Treatment

While scars cannot ever resolve completely, measures can be taken to improve their appearance. The use of creams and vitamin E oil is often used but does not appear to be as effective as once thought. Surgical excision of a scar can lessen the wide appearance of some scars. Laser treatments may take away the raised portion of a scar. Some doctors use steroid injections to help flatten scars.

While scares are forming, pressure garments can prevent a scar from becoming irregular or raised. Dermabrasion is often used to reduce the elevation of a scar. In the case of sunken scars, collagen injections can help raise them to a more normal level.