Anterior spinal veins

Anterior spinal veins
1: Posterior spinal vein 2: Anterior spinal vein 3: Posterolateral spinal vein 4: Radicular (or segmental medullary) vein 5: Posterior spinal arteries 6: Anterior spinal artery 7: Radicular (or segmental medullary) artery
Details
Artery	Anterior spinal artery
Identifiers
Latin	Venae spinales anteriores
Dorlands /Elsevier	v_05/12851730
TA	A12.3.07.024
FMA	70892
Anatomical terminology []

Anterior spinal veins (also known as anterior coronal veins and anterior median spinal veins) are veins that receive blood from the anterior spinal cord.

There are two major components to venous draining: the intrinsic vessels which drain first, and the pial veins which drain second. Within the intrinsic vessels are a group of veins known as central veins. These are organized into individual comb-like repetitive structures that eventually fuse together once in the ventral median spinal fissure. After their fusion the group of central veins drains its combined contents into an anterior spinal vein. These veins can infiltrate back into the ventral median spinal fissure previously mentioned by up to a few centimeters. They are also not only smaller in size but more numerous than the equivalent anterior spinal artery which they lie dorsal to.

There are three anterior spinal veins in total. These, along with three posterior spinal veins, are allowed to communicate with one another as they run interconnected throughout the entire length of the spinal cord. This is seen through both sets of veins combining to form a network of anastomoses around the conus medullaris. Together, these two sets of veins also collect blood from intramedullary radial veins as well as other veins. They are drained by the anterior and posterior radicular veins, respectably. Radicular veins appear blue to the naked eye. Next, both radicular veins travel to the epidural space by means of joining the internal vertebral venous plexuses. Ultimately, this plexus is able to send and receive information from the veins and sinuses inside the brain. The external vertebral venous plexuses is also available for the internal vertebral venous plexus to communicate with.

Anterior spinal veins fall into the intradural network of the vertebral venous system. The intradural network breaks down into the intramedullary and extramedullary systems which are sets of highly reliable veins. This is because they are vastly redundant in what they do and so only fail under exceedingly unfavorable conditions. Their dependability can be compromised, however, by the bridge that connects them. This fragile link across the dura mater of the spine is known as the radiculomedullary veins. Although these veins connect the trustworthy intramedullary and extramedullary veins, they have no support network to protect them and are seen in much fewer numbers by comparison. This may lead to complications such as thrombosis. For example patients that have spinal dural fistulas can experience venous hypertension caused by thrombosis of these veins.