Why does the ipsilateral pupil dilate following uncal herniation?
A) Because of pressure on the optic cranial nerve (CN I)
B) Because of pressure on the abducens cranial nerve (CN VI)
C) Because of pressure on the oculomotor cranial nerve (CN III)
D) Because of pressure on the trochlear cranial nerve (CN IV)

Question

Quizplus · Accepted Answer

Uncal herniation occurs when the uncus (part of the temporal lobe) shifts and compresses the oculomotor nerve (CN III). This results in ipsilateral dilation of the pupil.

Why Does the Ipsilateral Pupil Dilate Following Uncal Herniation