Absence of the great cerebral vein is quite rare.

Most conditions associated with the great cerebral vein are due to congenital defects.

Most of the blood in the deep cerebral veins collects into the great cerebral vein.

The great cerebral vein is one of the large blood vessels in the skull draining the cerebrum (brain).

The great cerebral vein of Galen is considered a deep/internal cerebral vein.

A malformed Great Cerebral Vein will be noticeably enlarged.

A possible complication of this tension is rupture of the great cerebral vein of Galen.

Thrombosis of the great cerebral vein is a form of stroke due to a blood clot in the vein.

Superior cistern (Quadrigeminal cistern or cistern of the great cerebral vein).

It forms from the confluence of the inferior sagittal sinus and great cerebral vein (great vein of Galen).

Therefore, when a child is diagnosed with a faulty Great Cerebral Vein of Galen, most parents know little to nothing about what they are dealing with.

There are both superficial/external and deep/internal cerebral veins, the great cerebral vein being a deep/internal vein as mentioned above) in the brain.

There is usually a venous anomaly downstream from the draining vein that, together with the high blood flow into the great cerebral vein of Galen causes its dilation.

The veins at the anterior poles of the thalami merge posterior to the pineal gland to form the Great Cerebral Vein of Galen.

It also contains the right and left internal cerebral veins (which drain the choroid plexuses) at its roof (the two veins unite to form the great cerebral vein).

In the absence of the great cerebral vein, the veins from the diencephalon and the basal ganglia drain laterally into the transverse sinus instead of conjoining in the midline through the Galenic drainage system.

These include superior vena cava syndrome (SVCS), and thrombosis of the lateral sinus, superior sagittal sinus, internal jugular vein, or of the Great Cerebral Vein of Galen itself.

Dilation of the great cerebral vein of Galen is a secondary result of the force of arterial blood either directly from an artery via an arteriovenous fistula or by way of a tributary vein that receives the blood directly from an artery.

They run backward parallel with one another, between the layers of the tela chorioidea of the third ventricle, and beneath the splenium of the corpus callosum, where they unite to form a short trunk, the great cerebral vein of Galen; just before their union each receives the corresponding basal vein.