logn-term efficacy and safety of hyaluronic acid fillers in the nasolabial fold treatment: a comprehensive assessment with 3D facial scanning, ultrasound imaging, standardized scales, and immune status evaluation

Objective. To evaluate the long-term efficacy and safety of hyaluronic acid fillers using a comprehensive assessment of laboratory and ultrasound markers of the immune and inflammatory response, tissue integration and biodegradation of the material, as well as aesthetic improvements according to standardized scales. Material and methods. This 12-month single-center, prospective, non-comparative study included healthy female volunteers aged 25–55 years (n=20) with clinical indications for the nasolabial fold correction. Participants received injections of a hyaluronic acid filler (24 mg/mL) in a total volume of 1–2 mL. Efficacy and safety outcomes were evaluated at several time points using a number of methods, such as 3D facial scanning, ultrasound imaging, laboratory diagnostics, etc. Results. Ultrasound imaging after filler injection revealed an increase in the total soft tissue thickness and subcutaneous fat layer thickness, both of which gradually returned to baseline over the follow-up period as the filler progressively resorbed. No inflammatory or infiltrative changes were detected at any follow-up point. According to the GAIS scores, the most pronounced aesthetic improvement was noted both by physicians (4.0) and participants (3.9) immediately after the procedure, followed by a gradual reduction in effect over the follow-up period. At all timepoints (7 days, 1, 6, and 12 months), no clinically significant inflammatory changes or pathological immune responses were detected based on immunological parameter assessment. Conclusion. Injection of a hyaluronic acid filler into the nasolabial fold area showed high efficacy and safety, without significant changes in the immune and inflammatory status of the participants.