Needle-free Subcision and Hyaluronic Acid Injection Using CureJet for Horizontal Neck Fold Reduction Assessed by Ultrasound and 3-dimensional Analysis.

Background: Horizontal neck folds (HNF) result from fibrous connections between the platysma and skin, often becoming more prominent with aging and skin laxity. This study aimed to assess the effectiveness of combining needle-free subcision and hyaluronic acid (HA) filler injections in improving the dermal and subcutaneous architecture of HNF using sonographic and 3-dimensional (3D) imaging tools. Methods: Twenty patients underwent 3 sessions of HA (Cleviel Wrinkle) injections for HNF. A needle-free injector (CureJet) was used in the first session to perform subcision via high-pressure microjets of HA, mechanically disrupting adhesions in the subcutaneous tissue. The second and third sessions involved 29G needle injections for volumization. Ultrasound and 3D imaging measured changes in dermal thickness, subcutaneous fat, and skin roughness. Results: Ultrasound showed significantly thinner subcutaneous fat in wrinkled areas (0.67 ± 0.26 mm) compared with normal regions (1.73 ± 0.32 mm), confirming fat loss as a key contributor to HNF. Posttreatment, subcutaneous fat thickness increased to 2.05 ± 0.41 mm, whereas dermal thickness improved from 1.02 ± 0.17 to 1.58 ± 0.26 mm. 3D analysis revealed a reduction in skin roughness, with the roughness average decreasing from 3.43 ± 0.73 to 1.79 ± 0.49. Mild bruising from subcision resolved within 7 days. Conclusions: HA injections effectively increased dermal and subcutaneous fat thickness, reducing the appearance of HNF without complications such as nodules or lumps. The combination of needle-free subcision for adhesion release and subsequent HA volumization provided both structural and aesthetic benefits, making it a promising approach for noninvasive neck rejuvenation.