Imaging diagnosis and evaluation for chronic venous insufficiency of the lower limbs        SHANG Dan*, YU Chong, LI Yi-qing. *Department of Vascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China 
Corresponding author: LI Yi-qing,E-mail:qzg599@126.com
SHANG Dan and YU Chong are the first authors who contributed equally to the article.
Abstract    Chronic venous insufficiency(CVI)of the lower limbs is a common clinical disease, mainly caused by primary or secondary deep venous valve insufficiency, which leads to venous reflux and elevated venous pressure, followed by a series of pathological and physiological changes and diverse clinical symptoms, this seriously affecting the quality of life of patients. How to make a clear diagnosis is very important for treatment and improvement of patient prognosis. The specificity of the symptoms and signs of CVI patients to evaluate their venous function is usually low. Simple medical history and physical examination cannot fully clarify the degree and anatomy of venous anatomy and functional abnormalities,so accurate examination methods are very important.At present,various imaging examination methods such as color Doppler ultrasound(CDU),CT venography(CTV),magnetic resonance venography(MRV),digital subtraction angiography(DSA),and intravascular ultrasound(IVUS)can effectively evaluate venous obstruction and reflux of the lower limbs,providing important basis for clinical diagnosis and treatment.