Abstract
Sclerotherapy is a widely used treatment for varicose veins; although numerous complications are documented, delayed complications are uncommon. This report describes an 82-year-old woman who developed a firm, nonpulsatile leg mass 3.5 years after ultrasound-guided sclerotherapy. Doppler ultrasound examination suggested a varicose collateral aneurysm, but atypical features and the risk of malignancy prompted surgical excision. Histopathology revealed a benign reactive vascular lesion, likely related to prior endothelial injury and thrombosis. This case highlights the importance of considering previous interventions when evaluating new vascular lesions and demonstrates that, although imaging is useful, histopathological evaluation is essential for accurate diagnosis and management.