This document summarizes how to perform an ultrasound scan to assess chronic venous disease in the lower limbs. It outlines the anatomy of the venous system, including the superficial and deep veins and perforating veins. It describes how to evaluate for reflux in the veins using Doppler ultrasound, and provides guidance on scanning the different areas of the lower limbs to investigate sources of reflux or varicose veins. The goal is to identify reflux or obstructions in the deep or…