First, it helps to know what kind of acne scars you have. On the body (chest and back), some people, particularly darker skin types, may have thicker scars called hypertrophic scars. These scars may benefit from injection with cortisone medication to thin out the scar. On the face, scars are more frequently atrophic instead of hypertrophic, meaning that there are depressions or divots in the skin. These atrophic scars can be divided into several types as follows:
- Ice pick scars: very small caliber, sharply demarcated depressions in the skin as if left by stabbing an ice-pick into the skin
- Boxcar scars: sharply demarcated circular or rectangular scars (larger caliber than ice-pick scars)
- Rolling scars: shallow depressions with softer edges and less deep than boxcar scars.
For ice-pick scars, since they are so small and deep, a helpful technique is punch excision. This means taking a small tool called a punch and removing a core of skin usually 2-3 mm wide. This area would then be closed with a suture to remove the defect in the skin. After healing, additional treatment might include laser therapy to smooth over the tiny healed scar from the punch excision.
High potency Acid Peeling Agents for Ice-Pick Scars:
An alternative to excision is application of high-potency peeling agents (such as trichloroacetic acid) directly into the scar with the tip of a needle or a sharp tip of a wooden applicator. The controlled injury of the skin can effectively cause the skin in an ice-pick scar to heal back together.
Generalized Chemical Peels for Boxcar and Rolling Scars:
For boxcar and rolling scars, a tried and true method of treatment is the mid- to high-potency chemical peel. These procedures are great because they are relatively widely available and tend to be lower cost than newer treatments. The downside is that chemical peeling can have some downtime and may sometimes leave hyperpigmentation in darker skin types. It also may not be as effective as other newer therapies. One advantage of chemical peels is that they help if acne is still occurring and can be part of an acne treatment regimen in addition to addressing the scars.
Subcision for Boxcar and Rolling Scars:
Another tried and true method of treatment is subcision, a technique where a sharp needle is inserted into the skin below the scar and moved back and forth to release the scar tissue from the underlying deeper tissue. Simply by causing a controlled injury there will also be stimulation of new collagen formation as well. This technique is often used in combination with other newer techniques.
Microneedling and/or Microneedling with Radiofrequency:
Microneedling is one newer technique that has been very successful in recent years. It involves a roller type of device that inserts tiny sharp needles into the skin as it is rolled over the tissue. It sounds more painful than it actually is because the needles are so very tiny. Microneedling is well-tolerated in all skin types and usually requires a series of treatments to create the desired effect. It works by creating small, controlled injury to the skin with the tiny needles. The healing process allows new collagen to form and lessens the appearance of the scar. Microneedling can sometimes be combined with a radiofrequency device that will heat up the collagen and also stimulate a healing response. Topical application of growth factor serums or even the patient's own platelet rich plasma are sometimes recommended with the microneedling technique.
Laser Resurfacing for Boxcar and Rolling Scars:
Laser resurfacing has been available for several years, but recent years have seen an explosion in the number of fractionated laser resurfacing devices. Fractionation of laser energy means that instead of creating injury to the entire surface of the skin, tiny dots of injury are made against a background of non-disturbed skin. This technique promotes rapid healing and has less downtime with less risk of discoloration of the skin. Multiple different devices are available. Resurfacing is best for boxcar and rolling scars but is less helpful for ice-pick scars.
Dermal Fillers for Rolling Scars:
Injection of dermal fillers into rolling scars and some boxcar scars can be particularly helpful. Hyaluronic acid is widely available and well-tolerated. Injection may need to be repeated over time as hyaluronic acid will dissolve over time. Multiple brand names of hyaluronic acid exist on the market.
A longer-lasting option is polymethylmethacrylate (PMMA) complexed with bovine collagen, otherwise known as Bellafill®. This newer filler is FDA approved for acne scar treatment and may last up to 5 years. A skin test is required prior to treatment to make sure no allergy to bovine collagen exists. This filler has shown particular benefit compared to other fillers in the acne scarring category. It can be combined with subcision to achieve maximal results.
Acne scar treatment is best addressed by different methods depending on the type of scar and the needs of the patient. Combining therapies such as subcision with filler injection or microneedling may be of particular benefit. Consult with your dermatologist regarding which treatments are right for you!