Varicose veins of the great saphenous vein (GSV) are a prevalent venous disorder, with higher incidence in women. They cause swelling, pain, ulcers, eczema, and phlebitis, impacting patients' occupational performance and quality of life. Endovenous laser ablation (EVLA) has been supplanted by high-level laser surgery (HLS) as the primary treatment for incompetent GSVs. EVLA uses laser energy to generate heat, altering or inactivating proteins and enzymes within the vessel wall. Occlusion rates are shown to be around 95% after one year. However, the influence of the untreated proximal segment adjacent to the sapheno-femoral junction (SFJ) on reflux and recurrence is ambiguous. Contemporary laser fibers, such as radially emitting fibers, can reduce postoperative discomfort and improve outcomes. However, data on the safety and long-term outcomes of flush ablation compared to standard ablation remains insufficient.

Varicose veins of the great saphenous vein (GSV) represent one of the most prevalent venous disorders, with a higher incidence in women compared to men. The manifestations of varicose veins include not only swelling and pain in the lower extremities but are frequently associated with ulcers, eczema, phlebitis, and other detrimental effects, resulting in an irreversible impact on patients' occupational performance and quality of life. To enhance this, it is essential to investigate appropriate treatments for clinical implementation (3). Current guidelines indicate that EVLA and other endovenous thermal ablation techniques have supplanted HLS as the primary treatment for incompetent saphenous veins, due to their demonstrated efficacy in numerous countries. In the EVLA treatment, laser energy is introduced into the lumen of the blood vessel, generating heat that alters or inactivates the proteins and enzymes within the vessel wall. Following the destruction of the vein wall's structure, the vein exhibits fibrosis, resulting in the contraction and permanent occlusion of the blood vessels. Endovenous laser ablation (EVLA) is an efficacious technique for addressing incompetent great saphenous veins (GSV) (5, 6, 7). Occlusion rates were shown to attain approximately 95% after one year (5). Notwithstanding favorable outcomes regarding the occlusion rate, the influence of the untreated proximal segment adjacent to the sapheno-femoral junction (SFJ) on the onset of reflux and recurrence following thermal ablation remains ambiguous (8, 9, 10, 11). Increased incidences of stump reflux following EVLA have been documented in comparison to high ligation and stripping (8, 9). Flessenkämper et al. demonstrated a significantly higher incidence of reflux from the SFJ into the GSV following EVLA alone compared to high ligation and stripping (HL/S) and HL plus EVLA (8). Rass et al. reported a 17.8% incidence of reflux in the GSV stump following EVLA and a 1.3% incidence after HL/S (9). The authors consequently reported a greater incidence of recurrent varicose veins in the groin compared to high ligation/stripping after five years (9). Contemporary laser fibers, such as radially emitting fibers, can diminish postoperative discomfort and enhance outcomes (12, 13). A modified radial fiber emits laser energy in two distinct rings radially around the tip. This is believed to produce a more uniform thermal effect on the venous wall, resulting in reduced pain and bruising post-procedure (14). These fibers facilitate the ablation of the GSV near the SFJ and may yield results comparable to high ligation (15). A comparable effect can be achieved with the 1-ring fiber, exhibiting a slightly elevated linear energy density (LEED) at the junction with the deep vein. This study will utilize the 2-ring fiber, as we favor a marginally diminished LEED at the tip to mitigate the risk of injury to the deep vein. Regrettably, data regarding the safety and long-term outcomes of flush ablation in comparison to standard ablation remain insufficient.

Inclusion Criteria:

• age 18-60 years.
• patients with CEAP classes C2 to C6
• primary great saphenous vein insufficiency with at least 0.5 seconds of reflux in the standing position on color Doppler ultrasound.

Exclusion Criteria:

• deep or superficial venous thrombosis
• previous treatment of the varicose veins
• severe infection in the ipsilateral lower limb
• GSV diameter more than15 mm or less than 3 mm
• ipsilateral lower limb arterial stenosis or occlusion;
• pregnancy or breastfeeding;
• iliac vein compression syndrome.
• congenital venous anomalies
• allergy to lidocaine
• Debilitating systemic disease.