Mapping Filler Nodules: Ultrasound Characteristics and Clinical Patterns in Dermal Filler Complications.

[BACKGROUND] The popularity of dermal fillers in aesthetic procedures has led to an increase in complications, including nodules that can be challenging to diagnose and treat. The role of ultrasound as a noninvasive diagnostic tool across different fillers remains underexplored.

[OBJECTIVE] To investigate the clinical features and ultrasound characteristics of dermal filler nodules.

[MATERIALS AND METHODS] The authors conducted a retrospective cohort study from February 2018 to December 2024, enrolling 62 patients with filler nodules referred to a tertiary center. Demographic data, filler types, clinical history, and cultures were collected and analyzed. Nodules were evaluated by ultrasound for their echogenicity, border definition, and internal architecture.

[RESULTS] Most patients were women (88.7%), with a mean age of 44.9 years. Hyaluronic acid was the most commonly reported filler, followed by polycaprolactone and poly-d,l-lactic acid. The midface was the most frequent site of nodule development. Ultrasound imaging revealed distinct, filler-specific characteristics: hyaluronic acid nodules evolved from anechoic "jelly" to hypoechoic "stormcloud" patterns; poly-d,l-lactic acid nodules presented as well-circumscribed hyperechoic "snow globe" formations; polycaprolactone ranged from fibrotic "dragon-beard candy" to layered "water ripple" patterns; and silicone resembled diffuse, ill-defined "snowstorm" echotexture.

[CONCLUSION] Ultrasound reveals filler nodule patterns, supporting more accurate diagnosis and safer, individualized treatment.