Valuable use of 3D in early and late 1st trimester fact or (still) fiction?

Purpose: The advent of novel US technologies has markedly improved our capabilities of early assessment of embryonic and fetal anatomy throughout the first trimester of pregnancy. In particular, three-dimensional reconstruction of normal and abnormal conceptions has given valuable insights into early human development. We herein demonstrate the potential of novel volume ultrasound applications in aiding the diagnosis of first trimester structural anomalies. Material and methods: All cases in which early embryonic demise had been confirmed and the CRL was reproducibly > 20 mm (n = 51) as well as all fetuses ≤14 completed weeks either affected by structural and/or chromosomal anomalies (n = 37) were enrolled in our study. US exams were primarily performed via a transvaginal approach, only in few cases a transabdominal scan was done. Results: In 23/51 miscarriages additional information could be obtained by 3D volume rendered images (including neural tube defects, craniofacial anomalies, ventral dysraphias). Applying 3D US in all other (viable) fetuses, even subtle structural lesions (micrognathia, cleft hand, facial clefts), CNS anomalies (Dandy-Walker-malformation) or skeletal abnormalities could readily be seen either during multiplanar or surface rendered imaging, highlighting the claim for adjunctive 3D US in those cases. Conclusion: Additional use of 3D US is proven to offer crucial information regarding both the etiology of early embryonic demise and distinct pattern of structural or genetic disorders of the developing fetus otherwise unobtainable during conventional 2D US.