Assessment of deep venous incompetence: a prospective study comparing duplex scanning with descending phlebography.

In this prospective study duplex scanning was performed in 21 consecutive patients (23 lower extremities) referred for descending phlebography. The grade of deep venous insufficiency (Grades 1-4) was estimated in a blinded fashion with phlebography and duplex technique. Agreement occurred in 15 of 23 lower extremities. Discrepancies were found particularly in patients with minor degrees of reflux. The patients with reflux below the knee according to phlebography were also identified with ultrasonography. The authors found duplex scanning to be accurate method of evaluating deep venous valvular function. With duplex--but not with phlebography--it was also possible to diagnose isolated lower extremity valvular insufficiency.