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. 1234 Objectives:To evaluate the long-term safety and clinical performance of a low-MoD (2%) HA filler (Volonic Light, Volonic Inc., 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 Inc., Korea).Injections targeted fine lines and contours in the mid-and superficial dermis.Follow-up visits were performed at 2 weeks, 6, 12, 18, and 24 months.Safety outcomes included early and delayed adverse events, particularly granulomas, delayed-onset nodules, and delayed inflammatory reactions.Clinical persistence was assessed by the treating investigator using standardized photographs; GAIS and patient satisfaction were evaluated at 6 months. Results:Across 60 patients and 24 months of observation, no clinically apparent granulomas, delayedonset nodules, or persistent inflammatory reactions were observed at any time point.Early postinjection events included transient edema (24/60, 40.0%) and ecchymosis (9/60, 15.0%), which resolved spontaneously within 7-10 days.At 6 months, investigator-rated GAIS was "very much improved" or "much improved" in 83% of patients (mean 2.1 0.6).Patient-rated GAIS showed similar results (mean 2.2 0.5), and 88% reported being "satisfied" or "very satisfied" with their aesthetic outcome.Progressive softening of effect was noted between 12 and 24 months, and by 24 months all treated sites were judged to have nearly or completely returned to baseline, without palpable residual nodules or irregularities. 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.These findings suggest a potentially favorable long-term safety profile in this limited cohort; however, rare Objective volumetric assessments (e.g., 3D photography or ultrasound) to quantify timedependent degradation Such work would help refine filler choice based not only on rheology and lifting capacity, but also on long-term immunologic safety and degradation behavior. | CONCLUSIONIn this 24-month prospective, single-arm cohort (n = 60), treatment with a low-MoD (2%) hyaluronic acid filler (Volonic Light) was not associated with clinically apparent granulomas, delayed nodules, or delayed inflammatory reactions.With 0/60 granulomas, the exact 95% CI for granuloma incidence was 0.0-5.9%,so rare events cannot be excluded.Aesthetic improvement and patient satisfaction at 6 months were favorable, and clinical effect diminished with nearcomplete resorption by 24 months.Overall, these findings support the feasibility of a low-MoD approach for fine-line correction and subtle facial contouring, while emphasizing the need for larger, controlled and preferably multicenter studies incorporating comparator fillers, blinded outcome assessment, and objective volumetry to establish robust evidence-based guidance on long-term safety and durability.
Yi et al. (Sun,) studied this question.