Three-dimensional sonographic evaluations of embryonic brain development.

OBJECTIVE: The purpose of this presentation is to show 3-dimensional development of the ventricles of the brain in early pregnancy, from 6 to 13 weeks, and to provide a reference for early diagnosis of central nervous system anomalies such as hydrocephalus and holoprosencephaly.

METHODS: From March 2007 to August 2007, 46 patients were included. All patients had routine first-trimester 2- and 3-dimensional sonographic examinations at the same time. All cases were examined with a Voluson 730 Expert or Voluson E8 ultrasound scanner (GE Healthcare, Milwaukee, WI) using a 4- to 8- or 6- to 12-MHz transvaginal probe. Volumes were reviewed and analyzed with GE 4DView release 6 software. After the inversion-rendering mode was selected, volumes were dissected by the MagicCut function to show the ventricles.

RESULTS: A total of 34 volumes from 7 to 12 complete gestational weeks were successfully dissected. Those before 7 and after 12 weeks could not be dissected properly. The crown-rump length ranged from 12.7 to 68 mm. Twelve representative images of the rendered volumes in chronologic order are shown. The brain volume dissections of 2 fetuses with ventriculomegaly and alobar holoprosencephaly are shown for comparison.

CONCLUSIONS: Early human brain ventricular structures could be evaluated in vivo with 3-dimensional sonography. This presentation shows the timeline of brain development and provides reference images to compare possible anomalies of development.