Long-Term Clinical and Histological Effects of a Bipolar Fractional Radiofrequency System in the Treatment of Facial Atrophic Acne Scars and Acne Vulgaris in Japanese Patients: A Series of Eight Cases

Objective: This retrospective case series was designed to compare the long-term safety and efficacy of bipolar fractional radiofrequency (FRF) therapy as a treatment for atrophic acne scars (ASs) and acne vulgaris. Background data: Few clinical and histological studies have examined the long-term utility of bipolar FRF therapy as a treatment for ASs and acne in people with darker skin. Materials and methods: Eight Japanese patients with ASs and mild-to-severe acne on both cheeks were treated with a bipolar FRF system (eMatrix; Syneron). Five treatment sessions with the same settings (coverage rate: 10%; peak energy: 62 mJ/pin; two passes) were carried out at 1-month intervals, and the patients were followed up for at least 1 year after the final treatment. Assessments of ASs and acne severity were performed and samples were removed for histological examination. Results: We demonstrated that mild ASs responded better than moderate and severe ASs, and at least 50% improvement in scar severity was seen in 50% of patients after the final treatment. Six patients remained disease free at 1.5 years without the use of any additional therapies. The biopsy specimens showed a marked improvement characterized by a decrease in dermal pilosebaceous units and perivascular inflammatory cell infiltrates with an increase in elastin content and collagen deposition in the upper dermis. Conclusions: Bipolar FRF treatment showed long-term effectiveness against mild ASs and acne in Asian patients and had minimal side effects.