Comparative study of four methods for quantifying Doppler ultrasound waveforms from the femoral artery.

Currently, there is no agreement as to the best method for quantifying Doppler ultrasound recordings from peripheral arteries in order to detect occlusive disease. The four methods assessed in this study are: the pulsatility index, height-width index, path length index, and a Laplace transform function index. Recordings of the Doppler ultrasound spectral waveforms from the common femoral artery of 232 limbs were digitized to obtain the maximum velocity waveforms. This data was analyzed and the various indices were computed and then compared with the arteriographic grades. The effect of distal disease was also examined. The diagnostic accuracy of each index was determined from receiver operating characteristics curves. We concluded that all four indices were capable of detecting significant aortoiliac disease with approximately equal diagnostic accuracy of 90-95% but that pulsatility index had the advantages of simplicity and ease of calculation.