Transvaginal power Doppler angiography of the fetal brain.

Using transvaginal B-mode sonography combined with power Doppler flow mapping on a total of 65 fetuses between 12 and 30 weeks of gestation, fetal intracerebral arteries and veins and blood flow were demonstrated in the coronal and sagittal planes. Clear images of the fetal brain and intracerebral vascular flow were obtained in 36 of the 65 cases. Bilateral vertebral arteries, the basilar artery and posterior cerebral arteries were imaged in the coronal plane at 12 weeks of gestation. Bilateral carotid and middle cerebral arteries were also depicted in the coronal plane at 13 weeks of gestation. The middle cerebral arteries and their branches were depicted via the anterior fontanelle in the coronal plane at 20 weeks of gestation. The anterior cerebral artery and its branches were demonstrated in the sagittal plane at 26 weeks of gestation. The fetal cerebral venous systems of the superior sagittal sinus, internal cerebral vein, vein of Galen and straight sinus were clearly imaged in the mid-sagittal plane. Although we encountered several problems with this new technology of transvaginal power Doppler sonography, we were able to demonstrate its potential to assess fetal intracranial blood flow during pregnancy.