8 Weeks Gestation


Case 1: Specimen and image information (ex-vivo)

Below are annotated images of fetus at 8 weeks gestation, imaged ex-vivo using 3D ultrasound imaging with CrystalVue and RealisticVue™ applied (CRL: 2.50cm; estimated gestational age 8+6 based on morphological characteristics;  range 8+6 – 9+6 weeks)

This specimen was matched to a Carnegie Stage 21 (CS21) embryo from the Carnegie Collection (CRL: 1.73cm; estimated gestational age 8+2, range 7+4 – 8+6 weeks based on CRL) Histological sections and a 3D embryological model of this specimen have been adapted from B.S. de Bakker, with permission and are used as a reference standard to validate and annotate anatomical structures visualised using 3D ultrasound imaging.

1. Coronal plane

A. 3D ultrasound volume with CrystalVue™ and RealisticVue™ rendering. The volume was sectioned in a coronal plane to visualise internal structures. 

B. Histological section from the Carnegie Collection. A matching imaging plane was selected to validate visualised structures. The original specimen was sectioned in the transverse plane. The sections were imported into a digital post-processing software (Amira, ThermoFisher Scientific) and aligned. From this imaging stack, the software can recreate other imaging planes, including the coronal imaging plane as demonstrated here. 

C. Annotated cross section of a 3D embryological model based on histological sections as shown in image B, the cross section was taken in the same imaging plane as image B. 

D. Annotated 3D ultrasound volume based on comparison with the histological sections and 3D embryo models as shown in images B and C. 

Image credit for images B and C3D Atlas of Human Embryology, B.S. de Bakker et al., An interactive three-dimensional digital atlas and quantative database of human develpoment, Science 2016; 354

2. Sagittal plane

A. 3D ultrasound volume with CrystalVue™ and RealisticVue™ rendering. The volume was sectioned in a parasagittal plane to visualise internal structures. 

B. Histological section of the matched specimen from the Carnegie Collection (reconstructed imaging plane). 

C. Annotated cross section of a 3D embryological model based on histological sections as shown in image B, the cross section was taken in the same imaging plane as image B. 

D. Annotated 3D ultrasound volume based on comparison with the histological sections and 3D embryo models as shown in images B and C. 

Image credit for images B and C3D Atlas of Human Embryology, B.S. de Bakker et al., An interactive three-dimensional digital atlas and quantative database of human develpoment, Science 2016; 354