Duplex ultrasound in the pre-operative assessment of varicose veins.

A technique for the pre-operative localization of sites of incompetence using B mode and Doppler ultrasound (duplex) is described. The reliability of this investigation was compared with the clinical assessment of a group of surgeons experienced in varicose vein surgery, and with the subsequent surgical findings. Duplex scans were found to be over 98% sensitive and 93-97% specific compared with the surgical findings. Clinical techniques were much less sensitive and specific, and in addition there was uncertainty about incompetence in up to 52% of cases. The place of ultrasound and comparison with other techniques is discussed. While this technique is widely used, especially in vascular laboratories, the technique has not previously been reported in detail.