3D Models Related Images

Anterior View of Structures at Atlantooccipital Region

Surgical Correlation


Anterior view of structures at atlantooccipital region. Bone of the lower clivus and adjacent parts of the occipital bone were removed to expose the medulla and its associated neurovasculature. The anterior margin of the foramen magnum has been preserved. Through this foramen the vertebral arteries ascend and subsequently unite at the pontomedullary sulcus to form the basilar artery. Prior to this union, they give rise to the posterior inferior cerebellar arteries, the largest branches of the vertebral arteries. Along the rostral lateral medulla emerge in sequence the glossopharyngeal (CNIX), vagus (CNX), and spinal accessory (CNXI) nerves. These nerves converge on the jugular foramen. The hypoglossal (CNXII) nerve exits the sulcus between the pyramid and olive and passes toward the hypoglossal canal. The occipital condyles articulate with the superior articular processes of the lateral masses of the atlas. The anterior arch of the atlas is located at the lower border of this image. (Image courtesy of AL Rhoton, Jr.)