Acne is a common condition that affects most people at some point in their lives. For reasons that are not understood some people develop severe acne that leads to permanent and sometimes disfiguring scarring. The term "scarring" refers to a process where collagen within the skin is damaged from inflammation, leading to permanent texture changes in the skin. However, many patients refer to scarring when they see color changes that remain for months after an acne lesion has healed. Scarring, color changes, and treatment options will be discussed below.
Types of Acne Scarring
There are different kinds of acne scarring: ice pick scarring, atrophic scarring, and hypertrophic scarring. Ice pick scars are deep pitted scars with steep edges. Atrophic scars are pitted but have smooth borders and are not as deep. Hypertrophic scar, more common on the back and chest, are thick lumpy scars that sit above the surface of the skin.
Color changes in acne in more common than scarring and can resolve but may take years to completely disappear. Color changes come in three basic flavors: post inflammatory erythema (pink and purple patches at the site of acne lesions), post inflammatory hyperpigmentation (brown/black discoloration at the site of the acne lesion), and post inflammatory hypopigmentation (white marks at the site of a healed acne lesion). Post inflammatory hyperpigmentation is very common in those with darker skin tones or in those who tan easily and can significantly worsen the appearance of acne.
Ethnic Skin and Acne Scars
Acne is one of the most common skin conditions in patients with darker skin. African American patients usually have post inflammatory hyperpigmentation and are at higher risk of scarring. Hispanics and those of Middle Eastern descent also commonly have post inflammatory hyperpigmentation. Asians have a lower risk of hyperpigmentation than African Americans, but higher risk than Caucasian patients. The risk of hypertrophic and keloidal scars is 5-15 times higher in African American patients and 3-5 times higher in patients of Asian descent. Thus, treating acne early, before scar formation and discoloration is recommended.
Treatment of Acne Scars
Acne scarring is permanent but can be treated. No treatment is 100% effective and the best result is improvement, not perfection. Treatment of scarring may require many different kinds of treatments, depending on the kind of scarring present. Treatment of acne scarring can be expensive and may not be covered by insurance. It is important that all the acne is clear before treating scarring. Otherwise, new scars form and the procedures are wasted. The most effective treatments are surgical and there are many types.
Mechanical resurfacing of the skin (see section on Dermabrasion) involves the use of abrasive tools to remove the outer layers of the skin to produce an improved appearance. Dermabrasion is primarily used for the treatment of acne scarring. Superficial and deep techniques are available. There are two layers of the skin; the outer layer is called the epidermis and the inner layer, the dermis. Superficial dermabrasion removes portions of the epidermis and deep dermabrasion removes all of the epidermis and portions of the dermis. Deep methods are the preferred method for treatment of scarring. Deep methods are effective but generally require weeks of healing time and carry a higher risk of complications. Improvements continue for months after the procedure as collagen remodels underneath the skin. It is important that the physician performing dermabrasion is experienced in the procedure. Dermabrasion has been proven to improve the cosmetic appearance of the skin, especially in the treatment of acne scarring. However, deep ice pick scars typically do not improve significantly with dermabrasion.
is a medium-deep or deep procedure and employs the use of a motorized brush or diamond cylinder. These tools are used to remove the outer layers of the skin in a controlled setting. Local anesthesia is used for pain control during the procedure.
In manual dermasanding, the physician abrades the skin with silicone carbide sandpaper. This method is usually considered to be a medium depth procedure and is sometimes used in combination with other methods, such as chemical peels, carbon dioxide lasers, and motorized dermabrasion.
Not everyone is a good candidate for dermabrasion. Those with active acne, infections, and other scarring skin conditions may need treatment before undergoing dermabrasion. Complications are rare but include infection, prolonged healing, hyperpigmentation, and scarring. Dermabrasion may not be recommended for those with darker skin types because of the risk of hyperpigmentation or darkening of the skin. You and your physician need to decide if dermabrasion is the right procedure for you.
Laser resurfacing (see section on Laser Resurfacing) has been used for the treatment of acne scarring. All lasers use a high-energy beam of light that targets specific structures in the skin. The CO2 and Erb:Yag lasers used for laser resurfacing are less specific and destroy the epidermis and superficial dermis. Like dermabrasion, laser resurfacing is ablative meaning that it destroys the outer layers of the skin. Ablative techniques are more effective but less popular because they require recovery time. Side effects are similar to dermabrasion and need to be discussed in detail with your doctor.
Subcision is used for atrophic scarring. Local anesthesia is used and a needle is then inserted under the scar and gently moved underneath the skin to release the scar tissue. This method has been tested in recent studies and shown to be effective.
Punch excision and grafting
For deep ice pick scars, the only effective treatment is complete removal of the scar. A small, round, cookie-cutter-like device (called a punch) is used to cut out the scar and the edges of the wound are then sewn together with a suture. In this case, a deep, large scar is traded for a tiny line scar that can later be treated to further blend into the rest of the skin. Larger scars can be removed and then filled with a skin graft, taken from skin (usually behind the ear). Grafts are later contoured with dermabrasion to blend them into the rest of the skin.
Substances that add volume to the skin (see section on Fillers) can be used alone or in combination with the above procedures. Fillers can improve the appearance of acne scars by flattening the scar but their effect is temporary. To maintain the result, the lesions must be re-injected at regular intervals.
Chemical peels, also known as chemical resurfacing (see section on Chemical Peels), are chemical treatments to produce an improved appearance of the face, including acne scars. Chemical peels produce controlled injury to the skin that promotes the growth of new skin with an improved appearance. Many different chemicals are used including glycolic acid, trichloroacetic acid (TCA), salicylic acid, “Jessners” solution, and phenol. The different chemical solutions produce different degrees of injury to the skin. Medium depth and deep peels produce injury within the dermis and can improve the appearance of atrophic acne scars. The deeper peels are more effective but carry more risks such as infection, scarring, and discoloration, especially for patients with dark skin. However, more studies are being performed in patients with dark skin and certain peels are proving to be beneficial. For example, in one study of Asian patients, glycolic acid peels (which are superficial) improved acne scarring and pore size. Further studies are in progress.
Treatment of Hypertrophic Acne Scars
Although less common, hypertrophic (and keloid) scars can be more disfiguring and harder to treat than other kinds of acne scarring. This type of scarring is more common on the chest and back. For reasons that are not understood, hypertrophic scars tend to recur after removal. Treatment usually involves topical steroids, injected steroids, silicone dressings, and/or cryosurgery. Recently, pulse dye lasers have been employed with some success. More work is needed in this area.
Treatment of Discoloration From Acne
Discoloration from acne (red, purple, brown, black, and white) is less permanent and easier to treat than acne scarring. However, it is also much more common. Both topical medications and surgical methods are employed.
• Topical Medications
Over-the-counter creams contain 2 percent hydroquinone, a bleaching agent. Prescription creams may use single agents, such as Retin-A (tretinoin) or combinations of medications such as hydroquinone with tretinoin plus a cortisone cream. These treatments can be quite effective when used properly. You need to discuss the risks of each medication with your doctor.
• Chemical Peels
Chemical peels are described above (and see section on Chemical Peels). In general, chemical peels are effective for improving discoloration from acne. More superficial peels have proven effective which is beneficial because there is less risk and less recovery time. However, several peels may be needed to obtain the desired effect.
Often referred to as a "lunch time" procedure (see section on Microdermabrasion), microdermabrasion is a popular procedure which is classified as light, or very superficial dermabrasion. This method employs aluminum oxide crystals that are propelled at the skin and immediately sucked up. Although not scientifically proven to improve the appearance of skin, many patients report that their skin feels smoother. It is used to treat acne, and the hyperpigmentation caused by acne. It is also popular because it is painless and there is no recovery time after the procedure. However, to effectively treat acne discoloration, up to 15 treatments may be necessary which can be very expensive. Newer devices now are crystal-less.
All photos courtesy of S. Zimmet, MD and P. Bitter Jr., MD