Interactive CS22 Embryo Model


The model is high resolution. Please allow time for it to load.

        Key to anatomical regions

  • Central nervous system
  • Eye
  • Ear
  • Dorsal root ganglia
  • Heart
  • Liver
  • Trachea
  • Lungs
  • Gastrointestinal tract

Movies of CS22 embryos


The movie below shows a micro-CT scan of a CS22 embryo. Sample staining and micro-CT was performed by Newcastle Preclinical In Vivo Imaging (PIVI) facility. 3D data-sets were acquired using Skyscan 1176, Bruker-microCT.

14916, male.


The movies below show volume renders of OPT models. Images of unstained specimens were captured using autofluorescence with a FITC filter.

N419 head 46XY
N419 body 46XY
N542 46XX





Painted Anatomical Regions


The movies below show anatomical domains defined in the N542 model. The domains have been manually defined in the OPT model using specialised software and then visualised using commercial rendering packages.

The various domains are: eye - dark blue; otic vesicle - yellow; dorsal root ganglia - cyan. The CNS domains have been further subdivided as follows: pallium - red, subpallium - orange, hypothalamus - light brown, prosomere 3 - bright green, prosomere 2 - green, prosomere 1 - dark green; mesencephalon - blue; isthmus - dark purple, metencephalon (rhombomeres 1-6) - purples/pinks; myelencephalon (rhombomeres 7-11) - magenta; spinal cord - maroon.

The top panel is a surface render of the 3D anatomical regions, and the middle panel shows the painted N542 model being digitally sectioned through the z-plane.


A 3D model of the head of a human embryo, Carnegie stage 22, with brain regions defined  

The movie below is a another surface render of anatomical domains within the brain of the CS22 model. Here the floor of the brain has been painted red, and the roof blue. For reference the rest of the neural tube is painted transparent grey.








Carnegie Stage 22 Definition



A 3D model of the head of a human embryo, Carnegie stage 22


Age is approximately 53 postovulatory days

Length is approximately 23 - 27mm

External Features Include: the hands extend further in front of the body and the fingers of one hand may overlap those of the other. The superficial vascular plexus of the head extends upward to form a line at approximately 3/4 of the way above the eye-ear level.

O'Rahilly R and Muller F [1987] Developmental Stages in Human Embryos. Carnegie Institute, Washington, Publication no. 637, and O'Rahilly R, Müller F (2010) Developmental stages in human embryos: revised and new measurements. Cells Tissues Organs. 192:73-84. PMID: 20185898.