About 95% or more of acne patients will be left with scarring, which seriously affects aesthetics. Acne scars are classified as proliferative or depressed, of which 75% of acne scars are clinically depressed scars, which can be classified as ice pick, carriage and wheel type scars according to their appearance. Clinically, inappropriate acne treatment can lead to aggravated inflammatory response and fibrous proliferation with surrounding tissues, which aggravates the scar manifestation. In addition, hyperplastic scars are more likely to occur in dark-skinned individuals and are also more likely to produce post-inflammatory hyperpigmentation.
Currently, the treatment options available for different types of acne scarring are filler therapy, chemical peel, surgical excision, dermabrasion and photoelectric therapy. Among them, photoelectric treatment for acne scar can be divided into fractional laser, intense pulsed light, pulsed fuel laser, micro plasma, radiofrequency treatment, etc. Nowadays, for acne scar, the most widely used fractional laser for skin reconstruction; exfoliative fractional CO2 and Er:YAG laser can be applied to the treatment of hyperplastic and acne scars.
For severe ice pick and compartmentalized scars, surgical excision or local dermal fillers with fractional lasers are used. However, post-operative adverse effects can be reduced by increasing the energy and decreasing the density. It can be applied to superficial and minor acne scars. For proliferative scars and keloids, a combination of intense pulsed light or pulsed fuel laser can also be used to perform vascular destruction and reduce the inflammatory response. In addition, for depressed scars, microplasma and fractional radiofrequency can also provide some efficacy.
In recent years, due to the continuous improvement and advancement of photoelectric technology, the treatment options for acne scarring have become more diversified, and different treatment modalities are chosen according to the patient’s acne scarring type, etc. Overall, fractional CO2 laser has better efficacy for ice-pick type acne scars, but has a longer downtime; microplasma comes second. For patients requiring a short downtime, radiofrequency microneedling and non-ablative fractional laser can be used, however, their efficacy is limited, while intense pulsed light and pulsed fuel laser can be used for destruction of proliferating vessels and reduction of inflammatory response in the early stages of scar growth.