RESUMEN
BACKGROUND: The efficacy of numerous hyaluronic acid (HA)-based fillers has been demonstrated by semi-quantitative and qualitative methods, useful in clinical practice, but poorly reliable. OBJECTIVE: To objectively evaluate the efficacy of a HA gel in treating nasolabial folds (NLFs) over a 9-12-month follow-up period. METHODS: A total of 47 adult patients with moderate to severe NLFs received one or two injections of HA gel. Efficacy was assessed by measuring NLF depth at time intervals up to 12 months subjectively by blind and open clinical scoring using the Lemperle scale, and objectively using skin replicas and in vivo 3D imaging methods. Tissue characterization and dermal thickness were also assessed using radiofrequency ultrasonography and high-resolution ultrasound imaging, respectively. RESULTS: The filler injection highly significantly decreased the depth of NLFs (p < 0.0001) at all time points, with an improvement of at least 1 grade in the Lemperle score in 77% and 89% of the subjects at 9 and 12 months, respectively. NLF volume measured on replicas and 3D images significantly decreased after injection and this improvement was maintained over 12 months. CONCLUSION: This HA gel is well tolerated and provides a significant and long-lasting correction of moderate to severe NLFs, as objectively demonstrated by instrumental methods.