Trigeminal Nerve Flashcards
What is the largest cranial nerve
Trigeminal nerve CN V
That is the nerve of the 1st pharyngeal arch
Timrigeminal
What are the 3 roots of the trigeminal nerve
Sensory (major)
Motor (minor)
Mesencephalic
Fibres of CN V arise from what ganglion
Semilunar ganglion or gasserian ganglion
Characteristics of semilunar ganglion
Develops from the neural crest
Consists of unipolar neurons
Crescent in shape
Located in the Meckel’s cavity (superior to the petrous part of the temporal bone)
Characteristics of motor root of the trigeminal nerve
Located in the pons
Medial to the gasserian ganglion
Passes through the foramen ovale
Joins the mandibular nerve
Supplies the muscles of mastication
Is trigeminal nerve a mixed nerve
Yea, it is.
I has small motor root and large sensory root
TMJ receives proprioception from
Periodontium
Teeth
Hard palate
TMJ
Fibres of sensory root of CN V arises from what
Gasserian’s ganglion
About the mesencephalic root
It’s the afferent station
The afferent fibres accompany fibres of motor root
Proprioception from TMJ, periodontal membrane, teeth, hard palate
Associated with afferent impulses from stretch receptors in muscles of mastication.
What are the 2 types of nucleus of CN V?
Motor nuclei
Sensory nuclei
What are the 3 types of sensory nuclei
Main (chief/principal) pontine nucleus ( located in the pons)
Mesencephalic nucleus (located in the midbrain)
Spinal nucleus
What are the 3 subdivisions of the spinal nucleus, there origins and extensions
Subnucleus Oralis: Originate in the pons and end at pontomedullary junction inferiorly
Subnucleus interpolaris: origjnates from the pontomedullary junction to the obex (medullospinal junction)
Subnucleus causalis: originates from the obex to the C3 level of spinal cord
Characteristics of the motor nucleus of the CN V
-Located at the midpontine level
-Medial to the main sensory nucleus
-fibres distribute to muscles of mastication (tempotalis, Massey we, medial and lateral pterygoid), myoihyliud, anterior belly of digastric, tensor tympani, tensor veli palatini.
Why is the location of the upper main nucleus
Midpons
What trigeminothalamic tract does the upper (main nucleus form)
Dorsal trigeminothalamic tract
What nucleus does ascending fibres of sensory root of trigeminal nerve terminate in
Upper (main) sensory nucleus
Where nucleus does desceding fibres of sensory root of trigeminal nerve terminate in
Motor nucleus
What impulses do upper (main) nucleus convey
Light touch, tactile discrimination, sense of position and passive movement
What is the true sensory ganglion of the CN V?
Mesencephalic nucleus
Mesencephalic nucleus can also convey impulse from what muscles
Extraocular muscles
What is the larger sensory trigeminal nucleus
Spinal nucleus
Origin and extent of spinal nucleus
Extends caudally from main nucleus to C3 level of spinal cord
What part of the trigeminothalamic tract does the spinal nucleus form
Ventral part
What impulse does the spinal nucleus convey
Pain and temperature
What impulse par oralis and interpolaris of the spinal nucleus convey
Tactile sense
What impulse does the pars caudaulis of the spinal nucleus convey
Pain and Temperature
What are the divisions of the trigeminal nerve
Ophthalmic V1
Maxillary V2
Mandibular V3
Principal nucleus is the nucleus of what division of trigeminal nerve
Ophthalmic division
Spinal nucleus is the nucleus of what division of trigeminal nerve
Maxillary (Spimax)
Mesencephalic nucleus is the nucleus of what division of trigeminal nerve
Mandibular
Trigeminal motor nucleus accompanies what nerve
Mandibular nerve (and motor branch passes the foramen ovale along with mandibular nerve, that’s why mandibular nerve has both sensory and motor innervation)
What nerve forms the smallest division of CN V
Ophthalmic nerve
What is the course of the V1
From anterior medial part of the semilunar ganglion, it passes through the lateral wall of the cavernous sinus
Areas the CN V1 innervates
Scalp, lacrimal gland, conjunctiva of eye, upper eyelid lining frontal sinus, skin of lateral angle of the eyeball, liming of ethmoidal cell
What does the principal sensory nucleus give rise to
Gasserian ganglion (in which the V1, V2 and V3 branches arise from) (refer to the picture on your phone)
Branches of the ophthalmic nerve
-Lacrimal
-Frontal
-Nasociliary
Branches of frontal nerve of V1
Supratrochlear
Supraorbital
What is the smallest beach of ophthalmic nerve
Lacrimal nerve
Course of lacrimal nerve
Enters the orbit through the narrowest part of the superior orbital fissure, then runs along the upper part of lateral Rectus muscle.
It communicates with the zygomatic branch of maxillary nerve.
It enters the lacrimal gland and gives off several filaments.
Finally m, pierces the orbital septum and end up supplying the skin of the upper eyelid.
What is the largest branch of the ophthalmic nerve
Frontal nerve
Course of the frontal nerve
Enters the orbit thorough the superior orbital fissure.
Runs forward between the levatotor palpebrae superioris and periosteum.
Divides into 2 branches midway between the apex and the base of the orbit.
What are the 2 branches of the frontal nerve
Supratrochlear
Supraorbital
Which is the smaller branch of the frontal nerve
Supraorbital nerve (it gives filaments that joins the infratrochlear nerve)
Areas the supraorbital nerve supply
Fikun over lower forehead
Skin over upper eyelid
Conjunctiva of eyes
Where does supratrochlear nerve pass through
Supraorbital foramen
Branches of the supratrochlear nerve
Medial and lateral branches
Areas the supratrochlear nerve supply
Conjunctiva
Skin over the upper eyelid
Twigs of pericranium
Course of the nasociliary nerve
Enters the orbit between the 2 heads of the Rectus lateralis and passes through the anterior ethmoidal foramen
Branches of the nasociliary nerve
Ethmoidal
Internal nasal (supplies the mucous membrane)
External nasal branch (supplies the skin and ala of the nose)
Long ciliary branches
Areas maxillary nerve supply (totally sensory)
From lower eyelids, side of the nose, upper lip, all maxillary teeth and gingival, mucous membrane of most nasal cavity, hard and soft palate, tonsillar region and region of pharynx
Branches of the nasociliary nerve
— Superior Alveolar nerves (anterior, middles and posterior)
— inferior orbital nerve
— Palatine nerves (greater and lesser palatine nerves)
— Zygomatic nerve (Zygomaticofascial nerve and Zygomaticotemporal nerve).
— Pharyngeal branches
— Nasopalatine nerve
— Superior laboal nerve
— Superior and inferior nasal nerves
About the zygomaticotemporal nerve
— It exits the zygomatic bone on it’s medial surface
— It then pierces the temporal fascia to supply the skin over the temple
— It receives branches from the lacrimal nerve
— It communicates with the facial and auriculotemporal nerve
About zygomaticofacial nerve
— Leaves the zygomatic bone through the lateral surface.
— Supplies the skin over malar prominence
Communicates with the facial nerve and inferior palpebral branch of maxillary nerve
Posterior superior alveolar nerves
Arise from the pterygopalatine fossa, leaves this fossa and enters the posterior alveolar canals.
Areas the posterior superior alveolar nerve supplies
Sinus lining
Three twigs to molars
Gingiva
Adjoining part cheek
Origin of middle superior alveolar nerves
Arise from maxillary nerve in the posterior part of the Infraorbital canal and runs in the Infraorbital groove on the lateral wall max sinus
Areas that the middle superior alveolar nerves supply
Gingiva
Premolars
Adjoining part cheek
The middle, anterior and posterior alveolar branches of the maxillary nerve forms what
Superior dental plexus
Anterior superior alveolar nerves is given off just before exiting the Infraorbital foramen, true or false
True
Areas that the anterior superior alveolar nerves supply
Canine and incisor teeth check the slides for more information (page 35)
anterior superior alveolar nerves does NOT communicate with the sphenopalatine ganglion, TRUE OR FALSE
False
What is the sensory innervation of the hard palate
Greater palatine and Nasopalatine nerves (these nerves pass through the pterygopalatine ganglion)
What is the sensory innervation of the uvula, tonsil and soft palate
Lesser (middles and posterior) palatine nerves
Areas the motor division of mandibular nerve CN V3 supply
-Muscles of mastication (temporalis, massetter, medial and lateral pterygoid muscles)
-Mylohyoid
-Anterior belly of digastric
-Tensor tympani
-Tensor Levi palatini
Areas the sensory division of mandibular nerve CN V3 supply
- Dura
- Skin
- Mucous membrane of chin, cheek and lower lip
- External ear region
- Parotid gland
- Lower teeth and Gingiva
- Anterior 2/3 of tongue
- Scalp over the temporal bone
- TMJ
What are the 2 branches of mandibular nerve
✨Branches from undivided nerve
- nervous spinosus
- nerve to the internal pterygoid
✨ Branches from divided nerve
- anterior
- posterior divisions
Anterior divisions of mandibular nerve
- External pterygoid
- Masseter nerve
- Nerves to the Temporal muscle (anterior deep and posterior deep temporal nerve)
- Baccal nerve
Posterior divisions of mandibular nerve
- Auriculotemporal muscle
- Lingual nerve
- Inferior alveolar nerve
What is a ganglion?
A ganglia is a cluster of cell bodies of neurons in the peripheral nervous system
Ciliary ganglion is suspended from what nerve
Nasociliary nerve
The ganglion of CN III is called what
Ciliary ganglion
The ganglion of CN V is called what
Semilunar or gasserian ganglion
The ganglion of CN IX is called what
Otic and submandilar ganglion
The ganglion of CN VII is called what
Prerygopalatine or sphenopalatine ganglion
The ganglion of CN X is called what
It’s called a wandering ganglion cos it doesn’t have a specific name (check your note)
The ciliary ganglion belongs to what nerve
Anatomically
Functionally
Anatomically - trigeminal nerve
Functionally - occulomotor nerve
Ciliary ganglion Carries parasympathetic motor fibre from what nucleus
Edinger- westphal nucleus
Otic ganglion is suspended from what nerve
Mandibular nerve V3
The otic ganglion belongs to what nerve
Anatomically
Functionally
Trigeminal nerve
Glossopharyngeal nerve
Check slide for the nerve distribution
Submandibular ganglion is suspended from what nerve
Lingual ganglion
The submandibular ganglion belongs to what nerve
Anatomically
Functionally
Trigeminal nerve
Facial nerve
(Check slide for the nerve distribution)
Pterygopalatine ganglion is suspended from what nerve
Maxillary nerve
The pterygopalatine ganglion belongs to what nerve
Anatomically
Functionally
Trigeminal nerve
Facial nerve
Check slide for nerve distribution
