====== Anterior medullary velum ======


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The [[superior medullary velum]] (anterior medullary velum, valve of Vieussens) is a thin, transparent lamina of white matter, which stretches between the [[superior cerebellar peduncle]]s; on the dorsal surface of its lower half the [[folia]] and [[lingula]] are prolonged.

It forms, together with the superior cerebellar peduncle, the [[roof of fourth ventricle]]; it is narrow above, where it passes beneath the facial colliculi, and broader below, where it is continuous with the white substance of the superior vermis.

A slightly elevated ridge, the fraenulum veli, descends upon its upper part from between the inferior colliculi, and on either side of this the trochlear nerve emerges.

Blood is supplied by branches from the [[superior cerebellar artery]].