2217 Cranial Nerves Slides
-
Upload
terence-au -
Category
Documents
-
view
228 -
download
0
description
Transcript of 2217 Cranial Nerves Slides
-
Human Neurobiology 910.217
Brainstem and Cranial Nerves II
Prof. Stuart Bunt
-
Human Neurobiology 910.217
Patterning of the cranial nerves
-
Human Neurobiology 910.217A reminder about embryology
-
Human Neurobiology 910.217
Names and NumbersUnderstand the names!
Olfactory I
Optic II
Oculomotor III
Trochlear IV
Trigeminal V
Abducens (t) VI
Facial VII
Vestibulocochlear VIII
Glossopharyngeal IX
Vagus X
Accessory XI
Hypoglossal XII
Sensory Sensory & motor Motor
-
Human Neurobiology 910.217
Nerves covered in other lectures
1 Olfactory 2 Optic 3,4,6 Extraocular eye muscles 8 Vestibulo-cochlear
5 Motor and Sensory to the face and muscles of mastication (sensory, motor and mesencephalic nucleus for proprioception)
-
Human Neurobiology 910.217
Note position of nerves on the brainstem
I Cerebrum
II Diencephalon
III, IV Midbrain
V Pons
VI, VII, VIII Junction : Pons-Medulla
IX, X, XI, XII Medulla oblongata
-
Human Neurobiology 910.217
Nerves run from 1 to 12
-
Human Neurobiology 910.217
Cranial nerves exit from the skull
except spinal branch of accessory (XI), which has some spinal roots
-
Human Neurobiology 910.217
Can use anatomical knowledgeto identify sites of lesions
Remember positions 1-12 Note many pathways
(which you will learn later) pass nearby
Cranial nerve symptoms usually pretty obvious
Often serious (brainstem involvement)
-
Human Neurobiology 910.217
Sensory cranial nerves 1. Olfactory, only sensation
to enter the cortex without passing through the thalamus (old sense?)
Rhinencephalon forms the cortex?
-
Human Neurobiology 910.217
Sensory nerves
2. Optic (chiasm) 8. Vestibulo-cochlear
-
Human Neurobiology 910.217
Motor nerves
3. Occulomotor extraolcular eye
muscles except:-
4. Trochlear (only one that emerges dorsally) trochlear muscle
6. Abducens lateral rectus
-
Human Neurobiology 910.217
Motor nerves (cont.) 11. Accessory 12. Hypoglossal
5. Trigeminal 7. Facial 9. Glossopharyngeal 10. Vagus
Mixed nerves
-
Human Neurobiology 910.217
Facial Nerve (a) The nerve of the second
arch Contributes to ear formation Tongue formation Facial musculature migrates
up over first arch
A mixed (sensory and motor) cranial nerve
Sensory from the ear Special sensory from the
tongue
-
Human Neurobiology 910.217
Facial Nerve (b)
Motor to the muscles of facial expression, stylohyoid, posterior belly of digastric and stapedius (to dampen loud sounds), all attached to structures derived from the second pharyngeal arch.
-
Human Neurobiology 910.217
Facial Nerve (c)
Viscero-motor (parasympathetic) to pterygopalantine ganglion
the glands of the mucosa of the nose and palate the lacrimal gland
submandibular ganglion submandibular and sublingual salivary glands
otic ganglion parotid gland
-
Human Neurobiology 910.217
-
Human Neurobiology 910.217
Innervation of the tongue
-
Human Neurobiology 910.217
Clinical Evaluation Upper Motor
Neuron cortex controls lower
opposite face forehead and eye
closure dual consensual reflexes
Lower Motor Neuron all muscles on oneside affected taste affected
-
Human Neurobiology 910.217
7th nerve damage
Bells palsy pain around ear no sensory impairment complete palsy rapid recovery(2-8wks) Entrapment in facial
canal after infection? steroids in severe cases
where taste affected
-
Human Neurobiology 910.217
Other 7th nerve lesions
Ramsay-Hunt syndrome Herpes Zoster of 7th
nerve very severe pain in ear vescicles poor recovery
Hemifacial spasm irritation of nerve by
blood vessel?
-
Human Neurobiology 910.217
Glossopharyngeal Nerve (9) Nerve of the third pharyngeal arch somatic motor to stylopharyngeus visceral motor to parotid via otic
ganglion special sense to the posterior 1/3 of the
tongue sensory to posterior pharynx, soft
palate, post. 1/3 of the tongue, tympanum, etc.
Sensory from Carotid sinus (pressure) and carotid body (pCO2)
Important for swallowing reflex.
-
Human Neurobiology 910.217
-
Human Neurobiology 910.217
Vagal Nerve (10) The wanderer cf vagrantnerve of 4th Arch Motor to all smooth muscle Secretory to all glands Afferent from all mucous surfaces in the gut
and its derivatives as far as the splenic flexure Motor to all muscles of the larynx, pharynx
and palate (except stylopharyngeus and tensor veli palatini)
Taste from a few taste buds on the epiglottis Inhibits cardiac muscle Sensory to the outer ear drum, external
auditory meatus and behind the auricle
-
Human Neurobiology 910.217
-
Human Neurobiology 910.217
-
Human Neurobiology 910.217
Accessory Nerve (11) Motor nerve to the
sternocleidomastoid muscle and trapezius
A somitic, spinal nerve that re-enters the foramen magnum to look like a cranial nerve. (accessoryto the vagus)
Has both spinal and brainstem origins
Damage leads to trouble turning the head
-
Human Neurobiology 910.217Hypoglossal Nerve
Motor nerve supplies occipital somite derivatives
Intrinsic and extrinsic muscles of the tongue
Leaves the brainstem above the olive as a series of small rootlets
Damage leads to deviation of the tongue towards the effected side