[A comparative study of benign and malignant pulmonary masses with coloured Doppler sonography].

In order to differentiate benign from malignant pulmonary masses by means of observing blood flow signal, with coloured Doppler sonography, the authors examined 67 in-patients who had been found having masses in the lungs by X-ray or CT. For comparison 43 benign cases showing blood signals in the lung was also examined. The results showed that the blood flow signals of all lung cancers were of relatively low blood flow resistance or arteriovenous shunting, while those of benign lesions were of high blood flow resistance. The pulsatility index in lung cancer was 1.02 +/- 0.30, the restance index was 0.52 +/- 0.13, the peak systolic velocity was 0.19 +/- 0.11 m/s, the end diastolic velocity was 0.06 +/- 0.02 m/s. The pulsatility index in benign pulmonary lesions was 1.53 +/- 0.30, the resitance index was 0.86 +/- 0.05, the peak systolic velocity was 0.28 +/- 0.05 m/s and the end diastolic velocity was 0.04 +/- 0.01 m/s. There were significant differences between the benign and malignant pulmonary lesions in the four indices (P < 0.01) by t test and t' test. Lower pulsatility index, lower resistance index, lower peak systolic velocity and higher end diastolic velocity were characteristics of malignancy.