Get access

A pictorial essay on fetal rabbit anatomy using micro-ultrasound and magnetic resonance imaging


  • Funding sources: ME and PD are beneficiaries of a Marie Curie Industria-Academia Partnership and Pathways grant sponsored by the European Commission (251356). JDP is beneficiary of a fundamental clinical research grant of the Fonds Wetenschappelijk Onderzoek (FWO) Vlaanderen ( and JR, JT, and LD from the ‘Klinische Opleidings- en Onderzoeks- Raad’ of the University Hospitals Leuven. BVC is a postdoctoral fellow of the Research Foundation - Flanders (FWO). Our experimental program is supported by the Flemish Hercules foundation (large infrastructure investments AKUL/09/033) and by the KU Leuven (OT/13/115).

  • Conflicts of interest: None declared



With this pictorial essay, we aimed to provide gestational age specific reference ranges of relevant fetal structures using micro-ultrasound, as well as its correlation with postmortem MRI and whole body sections.

Material and Methods

Time-mated pregnant rabbits (n = 24) were assessed once at various gestational ages in the second half of pregnancy (15, 17, 21 to 23, 25 to 28, and 30 to 31 days; term = 31 days). We obtained biometric data, together with Doppler flow patterns in the ductus venosus, umbilical artery and umbilical vein. After euthanasia, micro-ultrasound images were compared with images obtained by 9.4 Tesla MRI and whole body paraffin sections at 15, 23, 26, and 28 days.


We constructed biometric normative curves, which showed a significant correlation with gestational age. The pulsatility index (PI) in the umbilical artery decreased with gestation (PI = 5.746–0.2969(GA) + 0.004931(GA)2; R2 = 0.30), whereas pulsatility index for veins (PIV) in the ductus venosus remained constant (median PIV = 0.82 (0.60–1.12)). In this report, we provide an anatomical atlas of fetal thoracic development using both micro-ultrasound and MRI.


We describe anatomical fetal leporine development as can be visualized by micro-ultrasound and MR imaging. The reported reference ranges may be useful for researchers using the fetal rabbit model. © 2013 John Wiley & Sons, Ltd.