@7 months ago with 54 notes
Transtentorial herniation, Uncal herniation
occurs when the medial aspect of the temporal lobe compresses the free margin of the tentorium.
1. Compress CN III → ipsilateral pupillary dilation
※Note the parasynpathetic nerve of CNIII is first affected by compression, followed by motor nerve damage.
2. Compress ipsilateral Posterior cerebral artery → hypoperfusion of the primary visual cortex, contralateral hemianopsia
3. Compress ipsilateral crus cerebri → contralateral hemiparesis
sometimes contralateral crus cerebri is compressed, causing paresis which is ipsilateral to the mass lesion(Kernohan’s notch)
4. Duret hemorrhages = Hemorrhagic lesions in the midbrain and pons
[X] ←helpful site to study about herniation