The prevalence of severe chronic venous insufficiency (CVI) is significant in the growing octogenarian population. While radiofrequency ablation (RFA) is a standard minimally invasive treatment, robust data on its outcomes and safety profiles specifically in patients aged 80 years and older remain scarce. This study aims to evaluate the risks and benefits of RFA in this specific, high-risk demographic.This prospective, single-arm, single-center cohort study will enroll 50 patients (initial target sample size) aged ≥80 years with CVI classified as CEAP C3 to C6 and with confirmed great or small saphenous vein reflux. All participants will undergo endovenous RFA under tumescent local anesthesia. The primary outcomes are: 1) the great/small saphenous vein occlusion rate at 6 months, assessed by duplex ultrasonography, and 2) the change in disease-specific quality of life from baseline to 6 months, measured by the Aberdeen Varicose Vein Questionnaire (AVVQ). Secondary outcomes include occlusion rates at 1 and 3 months; complication rates (e.g., deep vein thrombosis, skin burns, paresthesia) within 30 days; and changes in the Venous Clinical Severity Score (VCSS) and the 12-Item Short Form Health Survey (SF-12) at predefined intervals over 6 months.This study is designed to demonstrate a high technical success rate (occlusion rate \>95% at 6 months) and a statistically significant improvement in AVVQ and VCSS scores at 6 months post-procedure. The collected data will provide a detailed profile of complication rates, characterizing the safety of RFA in this very elderly cohort.This study will provide crucial, prospective evidence regarding the efficacy and safety of RFA for treating CVI in octogenarians. The findings are expected to guide clinical decision-making and inform treatment guidelines for this vulnerable and expanding patient population.