Figure 14-60.

Coning of the Cerebellar Vermis, Brain, Cat.

A, Sagittal section. Coning of the cerebellum. The caudal cerebellar vermis has been displaced caudally through the foramen magnum; note the notch on the dorsal surface (arrow). This result has compressed the medulla oblongata (MO), which can cause death from compression of the respiratory center. Note the elevation of the corpus callosum (CC) and focal compression of the rostral cerebellar vermis by the tectum (quadrigeminal plate) (QP). B, Coning of the cerebellum through the foramen magnum, caudal view through the foramen magnum. Note that in this case not only has the cerebellar vermis (arrow) been displaced caudally, but also the medulla. The caudal cerebellar peduncles have been displaced caudally as far as the foramen magnum.

(A courtesy Dr. D. Cho, College of Veterinary Medicine, Louisiana State University; and Noah's Arkive, College of Veterinary Medicine, The University of Georgia. B courtesy College of Veterinary Medicine, University of Illinois.)