Though acne is not commonly treated in an aesthetic capacity, patients with acne scars often seek interventions from clinicians of various aesthetic backgrounds. Therefore, it's important for all cosmetic physicians to understand acne scars in their many varieties, particularly as treatment options continue to expand. Ahead, I will outline the clinical features of different types of acne scars and survey the evolving therapeutic landscape, in particular the increased role of microneedle resurfacing procedures.
EVALUATION OF ACNE SCARS
The physical and clinical features of acne scars can range greatly in color and depth. Discolored scars may be red (fresher scars) or brown. Brown scars are a result of post-inflammatory hyperpigmentation and are more commonly seen in patients with skin type III or darker. Rolling scars are soft, indented scars that resemble rolling hills. These scars are often distensible with stretching of the skin and respond better to treatment than deeper scars. Scars with a flat-bottom (boxcar scars) or in the shape of a point (ice-pick scars) and are still visible upon stretching of the skin and are often more difficult to treat. Another type of scar that is difficult to treat is the hypertrophic or keloid scar. These scars are elevated above the skin and feel indurated. They occur most commonly on the jawline, neck, chest, shoulders, and back. Often, these scars require additional therapy such as intralesional steroids or fluorouracil in addition to conventional approaches. Patients who have a tendency toward formation of this type of scar should be approached with caution if any resurfacing procedure is done. It is important to note that a single patient may exhibit multiple scar types.
Before treating acne scars, one important consideration to make is age, as many younger patients may still have acne that is creating new scars. In these cases, it is essential to get the patient's acne under control before treating the scars. Often times, patients will want to treat the scarring while treating the acne itself, and while some scars may improve with topical acne treatments such as with retinoids, it is best to avoid any resurfacing procedures until after the acne is resolved, since many of the therapies can cause flare-ups.
Age may also play a role in treatment, since scars that are not as old tend to respond to therapy better than scars that are 10 or 20 years old.
Another important issue regarding the treatment of acne scars is the patient's skin type. If the patient has darker skin, s/he might not be the ideal candidate for certain procedures including peels and laser therapy that may increase the risk of hyperpigmentation.
Acne scars can be treated with a range of modalities, from lasers and devices, to punch excision, as well as TCA and other topical products. Included in most of these are home care regiments, such as a retinoid to stimulate collagen that improves skin texture, a bleaching/brightening cream, and basic sun protection, all of which should be part of any clinical regimen.
For red scars or other facial erythema, a vascular laser can be effective. This may apply more to fair-skinned patients who are more prone to red acne scars. Treatment with a vascular laser often requires several sessions for optimal result.
For deep scars such as the boxcar and ice-pick types that don't respond as well to laser and other resurfacing treatments, one older technique is to do punch excisions. Using a 1mm to 2mm biopsy tool, the physician can cut out the scar and suture the treatment area. This essentially creates a flatter scar that can then be resurfaced with a device. Another older modality for deeper scars is chemical ablation, which involves the application of 80-100% TCA at the base of the scar using a sharp, wooden applicator. This helps to break down the scar tissue, which can be effective but comes with some risk. Unaffected skin should not be treated, as it can cause darker skin to pigment.
Another aggressive technique for deeper scars that has since diminished in popularity is subcision. This involves use of a Nokor needle to make an incision on patient's skin and then gliding the sharp edge of the needle under the skin surface to lift the scar and mechanically break up the scar tissue. One can then inject filler under the scar to maintain the lifted effect.
Within the last decade, ablative and non-ablative fractional laser resurfacing has become a go-to standard for many types of acne scars. Although fractional resurfacing is often effective, it is costly, can be painful for patients, and also comes with a risk of hypo- or hyperpigmentation.
One option for the treatment of acne scars that's emerged fairly recently is microneedle resurfacing. The newer mechanical variations of microneedle resurfacing perform what's known as percutaneous collagen induction therapy. This technology includes automated high-speed vibrating handheld devices with multiple stainless steel 32 gauge disposable needles at the tip. The needles penetrate the skin over 1,000 times per second with precise, vertical micro-wounds, stimulating emission of growth factors, fibroblast growth, and production of collagen and elastin. Due to the minimally invasive nature of the procedure, most patients experience three to four days of clinical healing time with erythema, mild swelling, and possible pinpoint bruising. However, despite the fact that the technique is wounding the skin, the procedure can be used safely in all skin types and body areas. Moreover, since there is no heat, there is less risk of hypo/hyperpigmentation.
During the procedure, patients will require topical anesthesia only. In addition to the needles being very small, the vibration of the device provides some modulation of pain due to gate control. Most devices allow for control of depth of treatment and several passes can be made depending on the fraction of skin coverage desired. Duration of treatment ranges between five and ten minutes, and the recommended number of sessions can be between three and six. The treatments can be spread apart by four to six weeks and benefits are gradual for up to six months as seen with other collagen-stimulating modalities. Patients may resume skin care with gentle, hypoallergenic products and sun protection immediately. Ideally, they would add a post-treatment skincare regimen that includes Vitamin C, growth factor product, oxygenation, hyaluronic acid, and a retinoid as tolerated.
Unlike most traditional resurfacing techniques, microneedling appears to have the benefit of less downtime, less risk, and real results. The procedure itself is fast, nearly painless, and relatively inexpensive, making it very desirable for patients. Younger patients are seeking it out for treatment of acne scars with less fear of physical and financial pain. It can also be used safely in patients of all skin types making it a safer staring point for treatment of darker skin patients. Moreover, microneedle resurfacing can be effective for patients with keloid scars, as well. It can be combined with topical products and other procedures such as intralesional steroid or fluorouracil injections for hypertropic scars.
Microneedling has become my first-line therapy for all types of acne scars. I like to perform the microneedling procedure first in many cases, and then tell the patient that we can incorporate other modalities in more severe cases or for resistant scars.
Unfortunately, no one treatment exists that can treat all acne scars effectively. Moreover, each patient may opt for a slightly different approach regarding care. But perhaps most important is that all acne scars are unique, and patients often have different varieties of scars depending on the skin type and location on the face or body. Thus, it is important for clinicians to consider the range of options when creating a treatment regimen.
Nancy Samolitis, MD is a Board Certified der- matologist with specialized training in cosmet- ic dermatology. She specializes in treatment of aging and sun-damaged skin on the face and body. Dr. Samolitis has lectured nationwide and has authored several peer-reviewed journal articles and textbook chapters. She has received a research grant award from the National Rosacea Society for the devel- opment of a project studying the effects of lasers and light therapy on rosacea. She is a fellow of the American Academy of Dermatology and the American Society of Dermatologic Surgery.