Clinical application of three-dimensional ultrasound in fetal brain assessment

Aim. To clarify the usefulness of three-dimensional (3D) ultrasound in the assessment of the fetal head and brain, according to 3D ultrasound surface reconstruction, multiplanar image analysis, three-dimensional angiography, and volume calculation. Methods. We examined 326 normal fetuses between 10 and 40 weeks of gestatio n using 3D ultrasound (Voluson, 530D, Medison, Seoul, Korea), mainly with t ransvaginal 3D transducer. Fetal head structures, such as skull, brain stru cture, and brain circulation, were presented by surface mode, multiplanar i maging mode, acid three-dimensional Doppler mode. After automatic volume ac quisition of the fetal head, image analyses were performed off-line, and 3D View software was used for volume imaging of the lateral ventricle and cho roid plexus in randomly selected 3D normal fetuses. Seven fetuses with intr acranial abnormalities were evaluated by 3D ultrasound functions. Results, Surface mode of 3D ultrasound objectively depicted in vivo develop ment of the cranial bones and formation of the cranial sutures and fontanel les in normal fetuses. Multiplanar image analysis of the brain structure pr esented a fetal brain in more cutting sections than conventional 2D ultraso und. Transvaginal 3D angiography was successful in 13% of normal fetuses an d rotation of 3D circulatory image allowed the analysis of the intracranial vessels. Volume imaging showed the individual intracranial structures, suc h as the lateral ventricle and choroid plexus. Intracranial abnormalities w ere longitudinally evaluated by 3D ultrasound and objective images helped i n reaching prenatal diagnoses. Conclusion. Advanced 3D ultrasonography and software for volume analysis ca n provide additional objective information about the fetal skull formation, brain structure, and brain circulation.