The venous system of the human foetal spinal cord. Scanning electron microscope of vascular corrosion casts.

The investigation was carried out on 16 human foetal cadavers at the age of 17-23 weeks from the time of conception. The foetal vascular system was injected with the synthetic resin MERCOX CL-2R and analysed in scanning electron microscope.The vascular system of the foetal spinal cord was studied. The foetal vascular system was characterised by high variability concerning the number, course and localisation of blood vessels. It contained numerous anastomoses with the internal spinal venous plexuses, which included anterior and posterior radicular veins. Large arteries running on the surface of the spinal cord are accompanied by the homoname veins. The venous system of the investigated foetuses was divided into 2 categories of veins: internal veins responsible for the drainage of blood from the central area, that is central and peripheral veins coming radially to the surface of the spinal cord and external veins, which form the venous system of the surface of the spinal cord. The venous system of the foetal spinal cord was also examined as to the presence of the valves.