Cranial Nerves

Smell (SSA)

Sight (SSA)

• EOM's (Med / Sup / Inf Recti, Inferior Oblique - GSE)
• Constrictor Pupillae (GVE)

Superior Oblique (GSE)

• Sensation to the Face (GSA)
• Muscles of Mastication (Temporalis, Massester, Medial and Lateral Pterygoids as well as the Tensor Veli Pallatini, Tensor Tympani, Mylohyoid, and Anterior Belly of Diggastricus - SVE)

Lateral Rectus (GSE)

• Muscles of Facial Expresion (GSE)
• Taste (Anterior 2/3's tongue - SVA)
• Salivation / Lacrimation (GVE)

• Hearing (SSA)
• Vestibulation (SSA)

• Sensation to the Patch
• Sensation from the Carotid Body and Sinus, posterior
• 1/3 of tongue, pharynx, and palatial arch
• Secretomotor innervation of the Parotid
• Taste to Posterior 1/3 of Tongue
• Motor Innervation of Stylopharyngeus

• Sensation to the Patch
• Sensation from the Pharynx, Larynx, and viscera to
• Thorax and Abdomen
• Motor innervation of all smooth muscles within the
• pharynx, larynx, thorax, and abdomen
• Taste to the epiglottis
• Motor Innervation to all striated muscles of the
• pharynx, larynx, and esophagus except the stlyopharyngeus and tensor veli
• palatini

• Trapezius
• Sternocleidomastoid

Tongue Momvement

• III
• IV
• VI
• XI
• XII

• I
• II
• VIII

• III (Edinger-Westphal Nucleus and Ciliary Ganglion)
• VII (Pterygopalatine and Submandibular Ganglia)
• IX (Otic Ganglion)
• X

• V
• VII
• IX
• X

Olfactory receptors in the nose send axons in the olfactory nerve through the cribiform plate of the ethmoid bone to the to the olfactory bulb where they synapse forming the olfactory tracts which run in the olfactory sulcus next to the gyrus rectus back to the primary olfactory cortex (piriform and periamygdaloid cortices). Secondary processing occurs in the orbitofrontal, entorhinal, hippocampal cortices.

• Traumatic Brain Injury (shearing along cribiform)
• Olfactory Groove Meningiomas (Foster-Kennedy Syndrome)
• Uncal Lesions (olfactory hallucinations)

• Formed by the axons of Retinal Ganglion Cells that perforate the sclera and become enclosed by the meninges. Optic Nerve passes posteriomedially through the orbit and out the Optic Canal into the Middle Cranial
• Fossa. The right and left Optic Nerves partially decussate at the Optic Chiasm and continue posteriorally as Optic Tracts to terminate in the Lateral Geniculate
• Body

• Emerges from the midbrain near the Cerebral Peduncle in the Middle Cranial Fossa and runs along the lateral wall of the Cavernous Sinus.·
• While in the Cavernous Sinus, CN III adopts sympathetic fibers from the carotid plexus
• CN III exits the skull via the Superior Orbital
• Fissure and splits into Supeiror and Inferior Divisions.

• Longest, smallest, and only nerve to exit from the dorsal brainstem
• Fibers that cross before exiting the brain at the level of the inferior colliculi then wind around the brainstem and pierces the dura to enter the Cavernous Sinus and run along its superior aspect through the Superior Orbital Fissure above the Tendonous Ring

• Emerges from the mid-pons and forms the semilunar (trigeminal) ganglion which rests in Meckel's cave in the middle cranial fossa.
• Divides into three branches - Frontal, Nasociliary, and Lacrimal - which enter the orbit through the superior orbital fissure.

• Emerges from the mid-pons and forms the semilunar (trigeminal) ganglion which rests in Meckel's cave in the middle cranial fossa.
• Passes through Foramen Rotondum to emerge within the Pterygpalatine Fossa where it gives rise to several branches and the Pterygopalatine Ganglion.
• Continues into the orbit through the infraorbital canal
• and exits the canal just below the eye to give rise to several terminal branches.

• Emerges from the medulla cranial to the vagus and passes through the Jugular Foramen where it has Superior and Inferior Ganglia.
• From there it follows the course of Stylopharyngeus passing between the Superior and Middle Constrictors of the Pharynx to reach the oropharynx and the
• tongue and gives off several branches

• Emerges from the lateral aspect of the rostral medulla and exits the skull via the Jugular Foramen where it has superior and inferior ganglia.
• Gives rise to several branches to the pharynx and larynx.
• Continues in the neck within the Carotid Sheath
• with the common carotid artery and internal jugular vein.

Emerges from the lateral brainstem on the lateral surface between the pontomedullary junction next to CN VII

• Emerges on the lateral surface of the brainstem between
• the Pons and Medulla as two roots (Motor and Nervus Intermedius).
• These pass through the Internal Acoustic Meatus entering the Petrous Portion of the Temporal Bone via the Facial Canal giving rise ot several branches (Greater Petrosal, Stapedius, Chorda Tympani).
• Remaining fibers continue through the facial canal and exit the temporal bone through the Stylomastoid Foramen and gives rise to numerous branches (Temporal, Zygomatic, Buccal, Mandibular, Digastric, Platysmal)

• Emerges from the brainstem between the Pons and
• Pyramid of the Medullar in the Posterior Cranial Fossa, pierces the dura, and passes through the Cavernous Sinus
• Enters the orbit via the Superior Orbital Fissure
• within the Tendonous Ring

• Emerges from the mid-pons and forms the semilunar (trigeminal) ganglion which rests in Meckel's cave in the middle cranial fossa.
• Exits the skull via Foramen Ovale and splits into anterior and posterior trunks.
• Anterior trunk carries most of the SVE fibers to the muscles of mastication.
• Posterior Trunk gives rise ot the Lingual Nerve which accepts taste fibers from the Chorda Tympani and forms the inferior alveolar nerve.

• Afferent: CN V1 (ophthalmic division)
• Efferent: CN VII (obicularis occuli)

• Afferent: CN V3 (mesencephalic nucleus)
• Efferent: CN V3 (motor nucleuus)

• Afferent: CN V1 (ophthalmic division)
• Efferent: CN VII (lacrimal gland)

• Afferent: CN V1 (opthalmic division)
• Efferent: CN X

• Afferent: CN IX
• Efferent: CN X

• Afferent: CN IX
• Efferent: CN X

Intermittent lancinating pain in the distribution of a branch of CN V which can be triggered by chewing.

• Herpes Zoster infection affecting the geniculate ganglion. Unilateral facial pain with vesicles in the external ear canal.
• Associated with loss of taste to the anterior 2/3’s of the tongue and hearing loss.

• Idiopathic (likely viral / post-viral) lesion of the facial nerve within the facial canal or as it leaves the stylomastoid foramen resulting in ipsilateral facial weakness in a peripheral pattern.
• Associated with loss of taste, pain, dry eye / mouth

• Disrupiton of the sympathetic fibers descending from the hypothalamus resulting in ptosis, miosis, and anhidrosis on the side of the sympathetic palsy. The enophthalmos is more apparent than real.
• The affected pupil is visibly slow to dilate in dim light; due to a lesion of the cervical sympathetic chain or its central pathways.

• Symptpms: Proptosis, Papilledema, and Painful
• Ophthalmoplegia
• Affects CN’s: III, IV, V1, V2, VI and postganglionic fibers along the ICA

Granulomatous inflammation of the cavernous sinus resulting in painful ophthalmoplegia which is treated with prednisone