The ultrasound can detect any malfunctioning valves in the phase of vein, indicating this phase is diseased. This is usually termed a venous reflux scan, given that the defective valves will generate refluxing circulation as detected with the ultrasound device. Sudden Swelling in One Leg: Unexpected swelling in one leg, https://www.sgvascularctr.com/swelling-leg-treatment-singapore/