Fractional radiofrequency with microneedling in acne scars

Acne can result in a variety of subtypes of scars; depending on the depth and severity of the inciting inflammation. Atrophic scarring limited to the epidermis and papillary dermis results in superficial macular scarring, which may be erythematous or hyperpigmented¹⁶. Involvement of the reticular dermis can result in ice-pick scars, boxcar scars, rolling scars, hypertrophic scars, and keloids^11,12. Ice-pick scars have a narrow aperture and penetrate deep into the dermis or subcutaneous tissue. Boxcar scars have sharp cliff-drop-like vertical margins and a larger, flatter base. Boxcar scars can be further subdivided into superficial and deep boxcar scars. Rolling scars occur from dermal tethering to the underlying superficial musculoaponeurotic system, with the appearance of gently sloping edges¹².

Chemical peels, subcision, augmentation using dermal fillers, ablative and non-ablative lasers, dermabrasion, dermal grafting, punch excision, punch elevation, punch grafting, and surgical excision are all available for the treatment of acne scarring^11–13. The following lasers have also all been applied for acne scarring:

• Pulsed dye laser¹⁴
• Non-ablative 1064 nm Nd:YAG¹⁵
• Non-fractionated 1320 nm Nd:YAG
• Non-fractionated 1450 nm diode^14,16
• Erbium-doped lasers (1410 nm, 1540 nm, and 1550 nm)
• Fractionated 1320/1440 nm
• Fractionated 2940 nm Er:YAG laser
• Fractionated 10600 nm CO₂ laser¹⁷.

The standard treatment for acne scarring is traditional, full-face CO₂ or Er:YAG laser resurfacing, with studies showing more favourable results with CO₂ lasers¹⁸. The non-fractionated, high-energy, pulsed CO₂ laser improves acne scars by an average of 80% with a single treatment¹⁸. Although ablative laser resurfacing produces the most dramatic improvement in acne scarring and texture, there is a significant risk of dyspigmentation, scarring, infection, and prolonged healing¹⁹.

The first publication on fractionated laser resurfacing was by Manstein et al in 2004²⁰. Fractional photothermolysis had the advantage over ablative laser resurfacing owing to a shorter recovery, lack of general anaesthesia, and lower risk of scarring, dyspigmentation, and infection¹³. Although originally described for rejuvenation of the ageing face, this concept was soon applied to acne scarring. In a small cohort of skin types IV–VI, 80% of patients had a minimum of 50–75% improvement in acne scarring after five treatments over a 1-month period using the fractionated 1550 nm erbium-doped laser²¹.

Figure 1 Active acne and acne scar (left) before and (right) after three treatments with microneedle radiofrequency

A meta-analysis reported that acne scars improved at least 50% with four to five treatments per month using a fractionated non-ablative laser²². After the development of fractionated non-ablative lasers, fractionated ablative lasers emerged. Cho et al²³ found an average of 60% improvement after a single treatment with a fractionated CO₂ laser, and in a study by Chapas et al²⁴, two to  three treatments with a fractionated CO₂ laser improved acne scarring by an average of 66.8%.

Peterson et al²⁵ reported improvements in acne scarring and texture of more than 60% with five treatments per month using a combination of fractionated laser with RF device and a fractionated bipolar RF device. The improvement of scarring is comparable with those of other non-ablative fractionated lasers. Rolling scars and boxcar scars improved more dramatically than ice-pick scars²⁵.