Download Cranial Nerves

Cranial Nerves
III
1
V
2
VI
VII
VIII
3
I
4
X
5
XI
XII
1
2
IV
3
4
5
6
7
8
9
10
Cranial Nerve 1: Olfactory Nerve
Anosmia
•Patients complain of loss of taste.
•Head injury is a common cause.
Cranial Nerve II: Optic Nerve
Cranial Nerves III, IV, VI: Oculomotor, Trochlear,
Abducens
Oculomotor
• Nucleus in midbrain
• Innervates 4 extraocular muscles and functions in most eye movements
• Contains parasympathetic which innervates pupillary constrictor muscles
and ciliary muscle of lens.
Trochlear
• Nucleus in midbrain
• Nerve exits dorsal surface and crosses over
• Moves eye medially and downward
Abducens
•Nucleus in pons
•Moves eye laterally
Cranial Nerve V: Trigeminal Nerve
•
•
Trigeminal ganglion
Ophthalmic, maxillary and mandibular divisions
•
•
•
Sensory: Touch, pain, temp, proprioception for face, mouth,
anterior 2/3 of tongue, nasal sinuses.
Motor: Muscles of chewing, tensor tympani muscle
Cranial Nerve VII: Facial Nerve
• Motor function: muscles of facial expression.
• Parasympathetic function: innervation of lacrimal glands and some
salivary gland.
• Visceral sensory function: taste from anterior 2/3 of tongue
Facial Nerve Lesions
cause paralysis in face
Bell’s Palsy
Facial nerve is impaired and then gradually recovers.
Cause unknown,(viral or inflammatory)
Cranial Nerve VIII: Vestibulocochlear Nerve
•Auditory and vestibular sensation
•Travels with facial nerve
•Branches go to cochlea, vestibule
Vestibular and Cochlear Sensory Organs
Lesions in Auditory Pathway
1. During auditory seizures: patients often report tones
from the side opposite the cortical area involved in the seizure.
2. Vertigo can be caused by damage to vestibular pathways
Cranial Nerve IX: Glossopharyngeal Nerve
•Motor function: stylopharyngeus muscle which elevates pharynx during
talking and swallowing and participates in gag reflex.
•Parasympathetic function: innervation of parotid salivary gland.
•Visceral sensory function: taste from posterior1/3 of tongue
Cranial Nerve X: Vagus Nerve
•Motor function: pharyngeal muscles (swallowing) & laryngeal muscles
(vocalization)
•Parasympathetic function: innervation of heart, lungs, most if digestive tract.
•Somatic sensation function: sensation from pharynx, meninges,
external auditory meatus.
Cranial Nerve XI: Spinal Accessory Nerve
Motor :
sternomastoid
upper trapezius muscles
Cranial Nerve XII: Hypoglossal Nerve
Motor function: intrinsic and extrinsic tongue muscles.