A duplex ultrasound can be a non-invasive means of detecting and quantifying the narrowing and blockage in the blood vessels. It truly is performed by a trained sonographer and it is verified by a Radiologist. It's really a painless technique performed on the couch and typically will take 1-2 hrs. https://sgvasculargrp.com/medical-condition/peripheral-arterial-disease/icon-peripheral-arterial-disease-pad-2-3/