Background: To find out outcomes of the day-case MOCA in the management of great saphenous vein (GSV) reflux. There is a rapid change in the management of great saphenous vein reflux in recent years. MOCA being minimal invasive instead of vein surgery, can be performed by percutaneous catheter ablation without incisions. Patients and methods: This prospective randomized controlled study was conducted on 78 cases (93 limbs); 63 cases with unilateral limb and 15 cases with bilateral limbs with GSV reflux. All patients were treated with MOCA using the Flebogrif catheter using duplex guidance without tumescent anesthesia. Follow-up period was for 6-months. Results: There was satisfactory results and marked improvement of patients' symptoms. Patients experienced significantly less postoperative pain at 1st 2 days (VAS: 1.9 ± 0.6). Patients were discharged within hours and returned back to work within few days. There were 1-week PO minor complications that disappeared by time except only 1 (3.3%) limb of DVT was treated conservatively. At 3-6 months there was residual varicosities only in 6 (6.6%) and treated by foam sclerotherapy. Conclusions: MOCA utilizing Flebogrif catheter and completion foam sclerotherapy are considered very promising interventions to treat GSV reflux; being less invasive, highly effective with good quality of life, less pain, satisfactory cosmoses and rapid return to work.