Varicose veins in the legs are usually associated with valvular incompetence of the LSV or SSV, & these conditions can be readily detected by CDU. This incompetence may be primary or secondary, but in most cases the causative factors are confined to the lower limbs themselves. In some cases, however, incompetence may be a result of factors within the pelvis or abdomen. Listed below are clinical & CDU features of leg veins that suggest possible abdomino-pelvic obstruction & should prompt the examiner to extend the scan to include the abdomino-pelvic veins.
• Atypical posterior or lateral thigh varices
•Clinical signs of venous stasis without adequate supportive lower extremity CDU evidence of incompetence
•Anomalous venous anatomy
•Incompetent or prominent tributaries tracking toward pelvic floor
•Unduly large diameter LSV (incompetent or competent)
•Varicosities with competent flow in LSV/SSV
•Common femoral vein thrombus
CDU assessment of abdomino-pelvic veins entails the application of low colour flow settings with optimal gain settings to clearly and accurately visualise colour flow defects, luminal reduction or stenoses which may result from extrinsic compression &/or the presence of venous collaterals.
Examples of atypical causes of venous hypertension include iliac vein thrombus, May Thurner syndrome or pelvic pathology causing extrinsic compression. Other esoteric examples will be included during the presentation. Atypical varicose veins may be a result of a plethora of causes. It is crucial to the patient’s outcome to reveal the true nature of the underlying cause.