Abstract
BACKGROUND: The degree of modification (MoD) of hyaluronic acid (HA) fillers reflects the extent of chemical cross-linking of native HA chains. Lower MoD values correspond to reduced cross-linker content and potentially more physiological behavior, but may also shorten filler longevity. Recent work on HA filler chemistry suggests that cross-linking intensity and impurity load contribute to delayed inflammatory reactions, nodules, and granulomas. OBJECTIVES: To evaluate the long-term safety and clinical performance of a low-MoD (2%) HA filler (Volonic Light, Volonic Co., Ltd., Korea) over 24 months, focusing on the incidence of granulomas, nodules, and delayed inflammatory reactions, as well as durability and patient-reported satisfaction. METHODS: In this prospective, single-center, single-arm cohort study, n = 60 adults underwent facial rejuvenation with a monophasic, lidocaine-containing HA filler with MoD 2% (Volonic Light; Volonic Co., Ltd., Korea). Injections targeted fine lines and contours in the mid- and superficial dermis. RESULTS: Across 60 patients and 24 months of observation, no clinically apparent granulomas, delayed-onset nodules, or persistent inflammatory reactions were observed at any time point. Early post-injection events included transient edema (24/60, 40.0%) and ecchymosis (9/60, 15.0%), which resolved spontaneously within 7-10 days. CONCLUSIONS: In this single-center, single-arm cohort (n = 60), a low-MoD (2%) HA filler was not associated with clinically apparent granulomas or delayed-onset nodules during 24 months of follow-up, and showed a predictable, near-complete clinical resolution of effect by 2 years.