DIAGNOSIS OF PULMONARY ARTERIOVENOUS-MALFORMATIONS BY COLOR DOPPLER ULTRASOUND AND AMPLITUDE ULTRASOUND ANGIOGRAPHY

Background-The clinical value of colour Doppler ultrasound and amplitu de ultrasound angiography in the diagnosis and follow up of pulmonary arteriovenous malformations (PAVM) was investigated. Methods-Six conse cutive patients suspected by clinical appearance and abnormal chest ra diographic findings of having PAVM were included in the study. Ultraso nography was performed first by real time grey scale imaging then by c olour Doppler imaging and amplitude ultrasound angiography in a random order. All were later proved by angiography to have PAVM. Results-The ultrasound study was successfully performed in all six patients. A to tal of eight lesions was detected. The real time grey scale image of P AVM revealed well defined hypoechoic subpleural nodules with strong po sterior acoustic enhancement. Colour Doppler ultrasound of PAVM showed turbulent flow, manifest as an area of intense colour with high and m ixed velocities (reticulated or mosaic-like pattern). Anatomical conti nuity was demonstrated in some PAVM. Amplitude ultrasound angiography can delineate a tangled vascular structure with a clear vessel wall an d anatomical continuity as well as conventional angiography. Spectral wave analysis showed a relatively low impedance flow presenting with h igh peak systolic velocity (mean 44.4 cm/s) and relatively high diasto lic velocity (mean 19.3 cm/s). The mean pulsatility index (PI) and res istive index (RI) were 1.80 and 0.49, respectively. In two patients wh o received embolotherapy the colour Doppler ultrasound scan obtained a fter the procedure showed-that the previous focal areas of colour flow signals disappeared or diminished in size. This was compatible with t he decrease in, or absence of, blood flow demonstrated by angiography after embolotherapy. Conclusions-Combined colour Doppler ultrasound an d amplitude ultrasound angiography are useful non-invasive techniques for diagnosing PAVM and provide an alternative approach to angiography in evaluating the efficacy of embolotherapy.