Trigeminal Nerve 1 Flashcards
what are the divisions of the trigeminal nerve?
- Ophthalmic Nerve (V1)
- Maxillary Nerve (V2)
- Mandibular Nerve (V3)
what is the exit point in the skull of the ophthalmic nerve?
superior orbital fissure
what is the exit point in the skull of the maxillary nerve?
foramen rotundum
what is the exit point in the skull of the mandibular division?
foramen ovule
how many bones is the hard palate composed of?
2 bones
what bones make up the hard palate?
- palatine process of maxilla
- horizontal plate of palatine bone
name the foramen found on the hard palate:
- Incisive foramen (anterior)
- Greater palatine foramen
- Lesser palatine foramen
what part of the mandible forms part of the TMJ?
the condylar process
what type of nerves control the muscles of mastication? where are these located?
- special visceral efferent nerves
- from the motor nucleus in the pons
what are the three types of general somatic afferent nerves called(sensory) ? where are these found?
- Mesencephalic (midbrain)
- Chief sensory (pons)
- Spinal nucleus (medulla oblongata)
what does the sensory mesencephalic nucleus control?
proprioception
what does the chief sensory nucleus control?
discriminative touch
what does the (sensory) spinal nucleus control?
- pain & temperature for structures supplied by CNV
- general consciousness sensation for the viscera controlled by CN IX & X
what is the function of the trigeminal nerve?
- the three divisions of the trigeminal nerve supply general somatic sensation to most of the face, head, and associated orbital, nasal and oral cavities
- the mandibular division also contains the motor root for the muscles of mastication
where is the trigeminal ganglion located?
Meckel’s cave on the apex of the petrous temporal bone
what is Meckel’s cave?
a cave of dura mater
what is meant if all three CNV divisions are affected?
the lesion must be in the pons or at the cranial base
If the CNV divisions are affected as well as other nerves too such as CN III & CN IV, what does this suggest in terms of the affected site?
the CNV affected site is likely to be in the cavernous sinus
what course does the ophthalmic division of CNV take?
- passes anteriorly in the lateral wall of the cavernous sinus
- reaches the superior orbital fissure
what are the main branches of the Ophthalmic Division?
- frontal
- lacrimal
- nasociliary
what does the frontal nerve (from the ophthalmic division) divide into? where does this correspond to on the face?
- supraorbital nerve
- supratrochlear nerve
supplies sensation to the skin of vertex and upper eyelid/forehead
what does the lacrimal nerve (of the ophthalmic division) innervate?
provides sensory innervation to:
- lacrimal gland
- skin of lateral upper eyelid and forehead
what does the nasociliary nerve (of the ophthalmic division) divide into?
- long ciliary nerves
- anterior & posterior ethmoidal nerves
- infratrochlear nerve
where does the external nasal nerve derive from?
its a continuation of the anterior ethmoidal nerve
where does the external nasal nerve innervate?
provides sensory innervation to the skin at the tip of the nose
where does the infratrochlear nerve innervate?
provides sensory innervation to the skin at the medial angle of the aye and adjacent root of the nose
what nerve supplies sensation to the cornea of the eye?
nasociliary nerve
what is shingles at the tip of the nose suggestive of?
warning sign that singles will also develop on the cornea
what is the course of the maxillary division of CNV?
CN V2 passes anteriorly in the lateral wall of the cavernous sinus & reaches
- the pterygopalatine fossa via the foramen rotundum
what is the pterygopalatine fossa?
an enclosed space (not fully enclosed) protected by bone
where is the pterygopalatine fossa located?
- lies just lateral to the upper aspect of the nasal cavity & nasopharynx
- behind the orbit & above hard/soft palate
where is the sphenopalatine foramen located?
in medial wall of pterygopalatine fossa
what are the main branches of the Maxillary division?
- zygomatic
- infra-orbital
- nasopalatine
- greater & lesser palatine
- alveolar
where do the zygomatic and infraorbital branches enter?
enter into the orbit via the inferior orbital fissure
where does the infraorbital nerve innervate?
- lower eyelid
- cheek
- side of nose
- upper lip
what does the zygomatic nerve divide into?
- zygomaticofacial nerve
- zygomaticotemporal nerve
where does the nasopalatine nerve travel tO/
the nasal cavity via the sphenopalatine foramen
what are the different divisions of the alveolar nerve (maxillary origin)?
- posterior superior alveolar
- middle superior alveolar
- anterior superior alveolar
what nerve supplies the upper central incisor, lateral incisor and canine?
anterior superior alveolar nerve
what teeth does the middle superior alveolar nerve supply?
the premolars
what teeth does the posterior superior alveolar nerve supply?
the molars
what nerve supplies the anterior of the hard palate?
nasopalatine nerve
what nerve supplies the anterior of the palate?
greater palatine nerve
where does the lesser palatine nerve supply?
very posterior of hard palate but also:
- soft palate and uvula
