Uncal herniation occurs when:
A)the hippocampal gyrus shifts from the middle fossa through the tentorial notch into the posterior fossa.
B)the diencephalon shifts from the middle fossa straight downward through the tentorial notch into the posterior fossa.
C)the cingulate gyrus shifts under the falx cerebri.
D)a cerebellar tonsil shifts through the foramen magnum.

Question

Quizplus · Accepted Answer

Uncal herniation (hippocampal herniation, lateral mass herniation) occurs when the uncus or hippocampal gyrus (or both) shifts from the middle fossa through the tentorial notch into the posterior fossa, compressing the ipsilateral third cranial nerve impairing parasympathetic function carried in the periphery of the nerve, then the contralateral third cranial nerve, and finally the mesencephalon, inducing coma.

Uncal Herniation Occurs When