Retrospective Study on Palpable Indurations After Cosmetic Filler Injection: Ultrasonic Characterization and Image-Guided Therapy

BACKGROUND: Minimally invasive filler injections are prevalent in aesthetic medicine. However, in recent years, the occurrence of complications has gradually increased. Current management lacks standardization, necessitating reliable imaging for diagnosis and treatment guidance. OBJECTIVES: This study aimed to evaluate the diagnostic value of high-frequency ultrasound in filler-induced indurations and explore its significance in guiding treatment strategy selection. METHODS: A retrospective analysis included 231 patients with indurations after filler injection (January 2023 to June 2025). All underwent high-frequency ultrasound (12-18 MHz); 70 received pathological biopsy. Biopsy was used to determine the nature of the lesions and establish the correlation between lesion type and sonographic features. Based on ultrasound characteristics, lesions were classified into 7 types and analyze the accuracy of ultrasound diagnosis and the efficacy of different treatment methods. RESULTS: The ultrasound-pathology concordance rate was 85.7%. The most common complications were accumulation of non-HA fillers (37.2%) and granuloma with non-HA fillers (22.5%). Non-HA filler granuloma responded better to noninvasive treatment (P < .001), while granuloma without residual filler and HA with granuloma favored invasive treatment (P = .001). Invasive treatment showed greater improvement in indurations (P < .001). CONCLUSIONS: High-frequency ultrasound accurately identifies types of complication, providing crucial evidence for individualized treatment selection. LEVEL OF EVIDENCE: 4 (THERAPEUTIC): For image description, please refer to the figure legend and surrounding text.