The demonstration of saphenofemoral incompetence; doppler ultrasound compared with standard clinical tests.

Patients with primary varicose veins were examined by a combination of the standard tourniquet test with detection of reflux by Doppler ultrasound. Results were compared with standard clinical tests: impulse or thrill at the saphenous opening on coughing, tap impulse at the groin, and the 'Trendelenburg' tourniquet test. The state of competence of the saphenofemoral junction was noted at operation. One hundred and sixty-one limbs of 105 patients were studied. The saphenofemoral junction was incompetent in 132/161 limbs (82 per cent) and was judged competent in 29/161 limbs (18 per cent). The combined Doppler and tourniquet test assessed the saphenofemoral junction correctly in 82 per cent of limbs and was more accurate than all the other tests. The test had good sensitivity (0.9) but poor specificity (0.45). Poor specificity was a feature of all the tests except for thrill which was a highly insensitive test. The combined Doppler and tourniquet test appears to be the most simple, rapid and accurate means of detecting saphenofemoral incompetence.