This document provides an overview of neuroanatomy as it relates to the ophthalmologist. It discusses the cranial fossae and their boundaries, cranial nerves III-VII, venous sinuses, and cerebrospinal fluid circulation. The oculomotor, trochlear, abducens, trigeminal, facial, and vestibulocochlear cranial nerves and their nuclei and pathways are described in detail.
8. Venous sinuses
Superior SS .
Inferior SS join the Great vein of Galen
Straight sinus.
SSS, straight S, and two transverse S.
frequenly join (confluence of sinuses).
Straight S Sigimoid S Int Jugular vein.
13. Oculomotor Nerve
Nuclei lie at level of sup colliculi.
Dorsally into the third ventricle.
Laterally: MLF.
Through tegmentum and
Red nucleus medial to
Crus cerebri.
14. Oculomotor Nerve
Interpeduncular fossa.
Lateral to PCOM (between PCA above and Post Cerebellar art.
Below).
Lateral wall of cavernous sinus SOF.
15. Oculomotor nucleus
MR subnucleus : 3 different masses.
SR subnuclue : innervates contralateral SR.
Central caudal nucleus: innervates LPS bilaterrally.
Visceral subnuclei: anterior median, Edinger-Westphal,
nucleus of Perlia.
17. Trochlear Nerve
Two nuclei in mesencephalon ventral to inferior colliculi.
Close to caudal end of IIIrd nerve nuclei.
Only somatic nerve to emerge from the dorsal aspect of the CNS.
Decussation (anterior medullary velum ).
Nucleus: anterior to periacqueductal gray matter.
18. Trochlear nerve
Around the crus cerebri between PCA and Sup cerebell art
(lateral to 3rd nv.) beneath the free edge of the tentorium
Pierces the dura and enters the lateral wall of the cavernous sinus
beneath the 3rd cranial nerve.
21. Abducens Nerve
Pierces the dura early upward on
The clivus.
Vertical Horizontal direction.
Runs beneath the petroclinoid
(Guber’s) Ligament.
Within the cavernous sinus (lateral
to the ICA).
22. Trigeminal nerve
Gessarian ganglion : Temporal bone within middle cranial fossa
(Meckel’s cave).
V1 SOF , V2 FR , V3 FO.
23. Trigeminal nerve
V1Sensory.
V2 carries PS from
The facial (superficial
Petrosal nv.) for
Lacrimation,
V3 Motor and
Sensory.
24. Facial nerve
Supranuclear neurons : in the frontal lobe
(pre-central gyrus).
Corticobulbar fibers in the middle of internal
capsule.
Fibers cross (below MB) cross to innervate
contralateral facial nucleus , some to
ipsilateral.