Diagnosis of fetal pulmonary hypoplasia by measurement of blood flow velocity waveforms of pulmonary arteries with Doppler ultrasonography

OBJECTIVE: The aim of the study was to determine the utility of ultrasonogr aphically recorded blood flow waveforms of the pulmonary artery in the diag nosis of pulmonary hypoplasia. STUDY DESIGN: The normal values of the pulsatility index and peak systolic flow of pulmonary arterial blood velocity waveforms were determined in 300 uncomplicated single fetus pregnancies with well-established gestational ag es between 24 and 40 weeks. We also measured the same parameters in 5 fetus es at high risk for development of severe pulmonary hypoplasia. We also det ermined the radial alveolar count and microvessel density, representing the extent of angiogenesis, in tissue specimens collected at autopsy from norm al and hypoplastic lungs and stained both with hematoxylin and eosin and im munohistochemically for factor VIII. RESULTS: In healthy fetuses the pulsatility index values of both the right and left pulmonary arteries diminished significantly with advancing gestati on, whereas the peak systolic velocity increased significantly with advanci ng gestation. In fetuses with pulmonary hypoplasia pulsatility index values were high and the peak systolic flow was significantly lower than in healt hy fetuses. Histologic examination showed a lower radial alveolar count and poorer angiogenesis in fetuses with pulmonary hypoplasia than in healthy f etuses. CONCLUSION: Doppler ultrasonographic determination of pulmonary artery broa d velocity waveforms is a useful tool for the diagnosis of pulmonary hypopl asia.