Acne Scars: Types and Treatment

"Old-looking" skin can sometimes have less to do with aging than with a defect that makes the skin look prematurely old. One such skin problem—and a fairly common one—is acne scars.

Acne is one of most common skin conditions in the world, afflicting 40 to 50 million Americans. Nearly 80 percent of people aged 11 to 30 years have acne, most often on the face, chest and back. However, acne is not restricted to any age group; adults in their 20s, 30s and even into their 40s can get acne. Most cases of acne responds to treatment and clears up without leaving scars. Healed acne does leave scars in some people, however, and it is not easy to predict who will have scars after acne and who will not. Severe, inflamed, cystic acne always leaves scars after healing, but in some people even superficially inflamed acne can result in scarring. (Click on AcneNet, an American Academy of Dermatology Web site, for comprehensive information on the causes and treatment of acne).

Whether acne scarring is deep or superficial, extensive or scattered, the esthetic result can be less than desirable and even disturbing. Acne scars can give the skin an "old" look. Scars may also contribute to an appearance of age as the skin loses its elasticity over the years (Click on Basic Facts About Aging Skin).

A number of treatments are available to remove or improve acne scars. The type and depth of scars influences the choice of treatment to a large degree. Here are some basic facts about acne scars:

Types of Acne Scars

Acne scars result from two types of tissue response to the inflammation of acne: (1) increased tissue formation, and (2) loss of tissue.

Increased Tissue Formation

Scars caused by increased tissue formation are caused by a build up of collagen (Glossary) in the skin. These are called hypertrophic and keloid scars. Keloid resulting from acne is shown in this photo:

Keloid-type acne scars on the back of a young man’s neck.

(Photos used in this discussion are with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides and the Sulzberger Institute for Dermatologic Education)

Keloids tend to "run in the family"—that is, there is a genetic predisposition to form keloids after tissue injury. African-Americans often have a predisposition to keloid formation. Some families also tend to form hypertrophic or thickened scars.

Scars Resulting from Loss of Tissue

Acne scars resulting from loss of tissue are more common than scars resulting from increased tissue formation. There are several types:

Ice-pick scars get their name from their appearance. They may be superficial or deep, are usually small in diameter and have steep sides like an ice-pick wound. They may be hard or soft to the touch; the soft scars are usually more superficial and the hard scars deeper. The base of hard scars under the skin may be wider than the scar at the surface of the skin.

Depressed fibrotic scars are usually large scars that have sharp margins and steep sides. They are similar in appearance to deep chicken pox scars.

Superficial and deep soft scars are variable in size, and have sloping edges that merge with normal skin.

Atrophic macules are soft, flat scars that often have a bluish or violet color on white skin due to underlying blood vessels. Macules tend to fade over time and become less obvious.

Treatment of Acne Scars

A person may seek treatment for acne scars (1) as a procedure to remove or improve the scars, or (2) in conjunction with an overall program of skin rejuvenation.

It is essential for the patient to discuss the desired outcome of the procedure with the dermatologist or dermatologic surgeon. Selection of a skin rejuvenation procedure may be guided, in part, by the result the patient wishes to have accomplished:

• Chemical peel
• Dermabrasion
• Laser or resurfacing of scars
• Soft-tissue augmentation
• Intralesional steroid injection (keloids)
• Excisional surgery in selected cases

(Click on Treatments for Aging Skin for a description of the procedures)

Chemical peels can improve small, depressed scars and some larger scars. Peeling may also be effective in treating any remaining acne by removing comedones (blackheads and whiteheads). Ice-pick scars and deep fibrotic scars are not treated effectively by chemical peels. Keloids are usually not treated by chemical peels. Repeated and/or deep peels may be necessary to improve deep or extensive scarring.

Dermabrasion was originally developed as a procedure to treat acne scars, and is still a procedure commonly used for that purpose. It can reach deeper layers of skin than a chemical peel and is a possible choice for treating both deeper and hypertrophic scars. In the past, dermabrasion was not considered effective in treating ice-pick scars because removal of the top layer of skin sometimes opened up a wider, fibrotic scar in deeper layers. Today a combination of dermabrasion and "punch" excision of scar tissue make many ice-pick scars treatable by dermabrasion.

Laser treatment of acne scars is a newer technology but one that can be very effective in selected patients. The various energy and tissue-penetrating power of different lasers may be used to treat complex scars. For example, the deep tissue penetration of a YAG laser may be used to "sculpt" irregular scarring and the infrared beam of the carbon dioxide laser may be used to tighten collagen fibers in the skin and elevate depressed scars.

Soft-tissue augmentation can correct some atrophic (loss of tissue) scars. Injections of subcutaneous fat or collagen under the scars elevates them to bring the surface of the scars even with the surface of surrounding skin. The procedure may have to be repeated from time to time. (Link to American Society for Dermatologic Surgery for more information about soft-tissue augmentation and other acne treatment procedures).

Injection of steroids directly into keloid scars can sometimes result in scar improvement. An intralesional injection can be combined with surgery to reduce the size of scars in carefully selected patients. Keloid surgery should be performed only by a dermatologic surgeon.

Acne scars are an unwanted reminder of a condition that can cause embarrassment and social isolation. Scars can also contribute to an appearance of premature aging. The good news is that acne scars can usually be treated by a dermatologist or dermatologic surgeon, and do not have to be endured.

References

Cunliffe W. The Acnes. (Chapter reprints from previous AcneNet Advisory Committee).

AAD Press Releases.

Roenigk HH, Jr. Treatment of the aging face. In: Roenigk RK, Roenigk HH, Jr. (Eds). Dermatologic Surgery. Principles and Practice. New York: Marcel Dekker, Inc.; 1996: 1057-1160.

Jordan RE, Cummins CL, Burls AJ, Seukeran DC. Laser resurfacing of acne scars (Cochrane review). Cochrane Database System Rev 2001; 1:CD001866.