Foramen caecum of medulla oblongata

The foramen caecum of medulla oblongata (Foramen of Vicq d'Azyr; Schwalbe's foramen) is the triangular-shaped superior expansion of the anterior median fissure of the medulla oblongata at its termination at the inferior border of the pons.

The foramen caecum is bounded laterally by the pyramid of medulla oblongata and the abducens nerve (CN VI) emerges lateral to the foramen caecum.

The foramen caecum have a high concentration of brainstem perforating vessels, mainly form the basilar artery, the anterior spinal artery and the AICA.

Its average dimension are 4,6 +/-0,16 mm.