The treatment of acne scars is often difficult as several evaluations are required to ensure realistic patient expectations, as well as to define acceptable results. The physician should assess the psychosomatic issues of acne scarring and gain patient trust before starting treatment.

Modalities Used for the Management of Acne Scars

The therapeutic options that are currently available to treat acne scars include excision, punch excision, subcision, cryosurgery, dermabrasion, microdermabrasion, chemical peels, ablative lasers, nonablative lasers, fractional lasers, silicone sheeting compression, dermal fillers and an emerging technique known as skin needling

Lasers come in a variety of wavelengths and energy settings. Knowing which lasers to use in the correct setting is imperative, as using the wrong setting or the incorrect laser can harm and even disfigure the patient. Patients with higher Fitzpatrick skin types tend to require lower energy densities. For patients who have acne scars with less fibrotic tissue, lower fluences should be used. Laser treatment should be avoided during acute or chronic cutaneous infections or inflammatory processes.

The acne scars should be properly evaluated and graded to determine the appropriate approach. In 2007, Goodman and Baron proposed a global acne scarring classification of four grades. The first grade consists of macular, hyper- or hypo-pigmented marks visible to an observer from any distance. The second grade consists of mild atrophy or hypertrophy, but can be covered by makeup or a shaved beard. The third grade is moderate atrophic or hypertrophic scarring, not easily covered by makeup or a shaved beard in men, that can be viewed at distances greater than 50 cm and can be flattened by stretching of the skin around the scar. The highest grade is severe atrophic or hypertrophic scaring that is visible at distances greater than 50 cm, and cannot be flattened by stretching the skin around the scar. Goodman and Baron recommend that nonablative lasers are appropriate for patients in the second grade, and ablative lasers may be used for patients who fit criteria for the third grade.

The two most commonly used ablative lasers for acne scars are the CO2 and erbium lasers. When using CO2 laser, atrophicscars generally improve by 50-80%. 

Fractional Lasers

Most recently Manuskiatti et al. demonstrated that atrophic scars in Asian patients can effectively and safely be treated with a CO₂ a blative FP. A total of 13 Asian patients who had Fitzpatrick skin type IV underwent four treatment sessions over a 7-week duration. Notably, the scar smoothness and volume improved in a statistically significant way compared with baseline at 1 and 3 months. In addition, 85% of the patients experienced between 25 and 50% improvement 6 months after treatment. A total of 92% of the treated patients experienced mild PIH that completely disappeared in a mean time of 5 weeks.

In a study by Alster and colleagues published in 2007, 53 patients with atrophic acne scarring were treated with nonablative FP on a monthly basis with a series of three Fraxel SR750 treatments. Two independent assessors evaluated clinical responses to treatment using a quartile grading scale. Nearly 90% of the patients showed an improvement of 51–75% after three treatments. Mean improvement scores increased proportionately with each successive laser session. Side effects included transient erythema and edema, but no dyspigmentation, ulceration or scarring was noted.  Similar results have been observed in some other studies.  The conclusions drawn on the basis of these studies was that FP improved the appearance of acne scars by as much as 50% after a series of four to five treatments performed on a monthly basis. Furthermore, FP significantly improved acne scars with PIH.

For post-treatment care, it has been recommended that semi-occlusive dressings or noncomedogenic moisturizers, but not occlusive ointments (e.g., petroleum jelly), are used in order to reduce acne flares. In addition, the use of post-treatment bleaching agents and daily sunscreen (minimum sun protection factor 30 with helioplex or mexoryl) may help to minimize the risk of PIH.

Expert Commentary

Acne scars are an unavoidable and frustrating complication of acne, ranging from slight hyperpigmented macules to atrophic scars or even hypertrophic scarring. It is advisable to treat acne and avoid development of new lesions in order to control the formation of new scars and, at the same time, treat the scars. Topical retinoids help with both acne and its scars. Chemical peels and dermabrasion are effective means of improving the appearance of acne scars.

The new modality being applied for the management of acne scars and becoming popular at a fast pace are lasers. Ablative and nonablative lasers have been tried for this purpose. Patients with atrophic scars are good candidates for laser treatment. There has always been apprehension about using lasers on darker skin types owing to complications of dyspigmentation and other complications. With more and more studies on darker skin types being treated with lasers, safer treatment protocols are being used with fewer reports of complications.

In our experience, lasers have a great advantage, including greater precision, less bleeding and discomfort, and possibly shorter recovery time over the modalities discussed above. Although the outcomes of laser resurfacing of acne scars can vary substantially depending on the skill and technique of the surgeon, in the right hands, lasers can be a very effective treatment.

The procedures with these lasers are associated with mild adverse effects, such as slight pain, erythema, edema, slight scaling and bronzing of skin. Ablative lasers are associated with more drastic effects, such as bleeding, oozing and increased downtime. Cooling modalities used in conjunction with these lasers alleviate the pain to a great extent. Topical anesthesia may be employed in certain cases.