Nerves of Head/Neck Flashcards
Anterior Superior Alveolar Nerve
Branch of: Infra orbital Nerve < Maxillary Nerve (V2) < Trigeminal (CN-V)
Its Branches: Nasal branch and dental branch
Supply to: sensory innervation to maxillary sinus, anterior maxillary oral mucosa, the incisor and canine teeth and the lower lateral nasal wall
Location: between the inner and outer tables of bone of the maxilla
Inferior Alveolar Nerve
Branch of: Posterior Division of Mandibular (V3) < Trigeminal (CN-V)
Its Branches: nerve to mylohyoid (before mandibular foramen) and incisive nerve and mental nerve (after already entering mandibular foramen)
Supply to: motor supply to the mylohyoid and the anterior belly of the digastric muscle (n. to mylohyoid)
and sensory supply lower dentition: molars and premolars
Mental nerve - skin of the chin/lower lip through mental foramen
Location: Emerges between the Lateral Pterygoid and Medial Pterygoid muscles along with the lingual nerve deep to lateral pterygoid muscle and lateral to the pterygomandibular raphe, between the sphenomandibular ligament and the ramus of the mandible.
Abducens Nerve (CN-VI)
Cranial Nerve 6
Comes from Pons (Metencephelon)
Motor ONLY
Motor to Lateral Rectus (extraocular muscle)
Travels through Superior Orbital Fissure (between greater and lesser wing of Sphenoid Bone in Middle Cranial Fossa)
Olfactory Nerve (CN-I)
Cranial Nerve 1
Origin: Telencephalon (from Prosencephalon)
Sensory ONLY
Nasal cavity for sense of smell
Travels through Cribiform Plate (Ethmoid bone in Anterior Cranial Fossa)
Fibers synapse in Olfactory Bulb
Optic Nerve (CN-II)
Cranial Nerve 2
extension of brain; surrounded by cranial meninges
Origin: Diencephalon (from Prosencephalon)
Extension of Brain/surrounded by cranial meninges
Sensory ONLY
Carries afferent fibers from retina to visual centers of brain (thalamus)
Travels through Optic Canal with Opthalmic Artery (lesser wing of sphenoid in middle cranial fossa)
Also, the central artery of retina travels in center of optic nerve and occlusion leads to blindness
Optic disc
– Where optic nerve leaves retina
– Blind spot
Occulomotor Nerve (CN-III)
Cranial Nerve 3
Origin: Midbrain (Mesencephalon)
Branches: Superior branch and Inferior Branch
Superior branch: Motor innervation to the superior rectus and levator palpabrae superioris. Sympathetic fibres run with the superior branch to innervate the superior tarsal muscle.
Inferior branch: Motor innervation to the inferior rectus, medial rectus and inferior oblique.
Parasympathetics to the sphincter pupillae and ciliary muscles. (constrictors pupil and ciliary body)
PATHWAY FOR PARASYMPATHETIC INNERVATION:
1) Edinger-Westphal Nucleus in the midbrain leave the brain with the Occulomotor Nerve
2) Through the Superior Orbital Fissure, travels to the Ciliary Ganglion (technically inferior branch) and SYNAPSES at the Cilary Ganglion
3) Postganglionic Parasympathetics then hitchhike onto the SHORT CILIARY NERVES (branch of nasociliary nerve which is a branch of the opthalmic nerve (V1))
4) innervates constriction of pupil
Trochlear Nerve (CN-IV)
Cranial Nerve 4
Origin: midbrain (mesencephalon) posterior aspect of the midbrain (it is the only cranial nerve to exit from the posterior midbrain)
Motor ONLY
Motor to Superior Oblique muscle (extraocular m.)
Travels along the lateral wall of the cavernous sinus (along with the oculomotor nerve, the abducens nerve, the ophthalmic and maxillary branches of the trigeminal nerve and the internal carotid artery) before entering the orbit of the eye via the superior orbital fissure.
Trigeminal Nerve (CN-V)
Cranial Nerve 5
Derivatives of the 1st Branchial (pharyngeal) Arch
SENSORY CELL BODIES ARE LOCATED IN THE TRIGEMINAL GANGLION LOCATED IN A FOSSA LOCATED IN THE ANTERIOR PORTION OF THE PETROUS BONE IN THE MIDDLE CRANIAL FOSSA.
Origin: Pons (Metencephalon)
sensory part arises from the trigeminal ganglion (trigeminal ganglion is located lateral to the cavernous sinus, in a depression of the temporal bone. This depression is known as the trigeminal cave.(Meckel’s cave) a recess located between endosteal and meningeal dura)
The motor and sensory
components of V3 join within foramen ovale or in the ITF. The cell bodies of the lower motor
neurons in V3 are located in the trigeminal motor nucleus within the pons.
Mixed (Both Motor and Sensory)
skin of the face; mucous membranes of the nasal and oral cavities; general sensation (GSA) to the anterior 2/3 of the tongue
carries hitchhiking postganglionic parasympathetic fibers, but not considered parasympathetic nerves
Gives to 3 divisions:
“Standing Room Only”
ophthalmic (V1) = sensory
maxillary (V2) = sensory
mandibular (V3) = both
The ophthalmic nerve and maxillary nerve travel lateral to the cavernous sinus exiting the cranium via the superior orbital fissure and foramen rotundum respectively. (Foramen Rotundum leads to Pterygopalatine Fossa) The mandibular nerve exits via the foramen ovale entering the infra-temporal fossa.
Ophthalmic Nerve (CN-V1)
Branch of: Trigeminal
Its Branches:
Frontal
- Supra-orbital Nerve (supraorbital foramen) - Supratrochlear Nerve (supratrochlear notch)
Lacrimal
Post ganglionic fibers from the pterygopalatine ganglion (derived from the facial nerve), travel with the zygomatic branch of V2 (zygomaticotemporal) and then join the lacrimal branch of V1. The fibers supply parasympathetic innervation to the lacrimal gland.
Nasociliary Nerve (superior orbital fissure)
- Anterior ethmoidal (foramen with same name)
- Posterior ethmoidal (foramen with same name)
- Small communicating branch to ciliary ganglion
- Infratrochlear (skin and conjunctiva of the medial upper and lower eyelids; skin of the lateral surface of the nose; inferior to the trochlea (pulley) of the superior oblique m.)
- Long ciliary nerve
- Short ciliary nerves
SENSORY ONLY
Supply to: innervate the skin and mucous membrane of derivatives of the frontonasal prominence (UPPER FACE)
Forehead and scalp Frontal and ethmoidal sinus Upper eyelid and its conjunctiva Cornea (see clinical relevance) Dorsum of the nose
Location: Superior Orbital Fissure
Maxillary Nerve (CN-V2)
Branch of: Trigeminal
Its Branches:
- Pharyngeal Nerve (palatovaginal canal)
- Nasopalatine (sphenopalatine foramen)
- Greater Palatine (greater palatine foramen)
- lat. posterior inferior nasal nerve - Lesser Palatine (lesser palatine foramen)
- Posterior superior lateral nasal nerve (sphenopalatine foramen)
Infraorbital Nerve (infraorbital foramen)
- Middle superior alveolar
- Anterior superior alveolar
-Inferior palpebral (face)
– Superior labial (face)
– Lateral nasal (face)
*Posterior Superior Alveolar Nerve (nerve before pterygomaxillary fissure exits foramina in maxillary tuberosity)
- Zygomatic (enters orbit via inferior orbital fissure)
- Zygomaticofacial
- Zygmomaticotemporal
SENSORY ONLY** THINK PTERYGOPALATINE FOSSA!!!!!!!!!!!!! *=in the PPF
Supply to: skin of the upper lip, cheek, lower eyelid; mucous membrane of the palate; teeth and gingiva of the maxillary alveolar arch; the mucous membrane lining most of the nasal cavity; the mucous membrane lining the maxillary sinus
Location: Passes through the Foramen Rotundum to enter the pterygopalatine fossa; the pterygopalatine ganglion is associated with it in the pterygopalatine fossa; postganglionic parasympathetic fibers distribute with branches of the maxillary division to mucous glands of the nasal cavity and palate; the zygomatic n. & its brs. carry postganglionic parasympathetics to orbit to reach the lacrimal n. and lacrimal gland
Mandibular Nerve (CN-V3)
Branch of: Trigeminal Nerve
Its Branches:
Trunk of V3
- Medial Pterygoid
> tensor veli palatini
> tensor tympani
- Nervus Spinosus
Anterior Division (motor)
- lateral pterygoid n.,
- masseteric n., (sensory to TMJ)
- anterior and posterior deep temporal n.,(post. sensory to TMJ)
- long buccal n. (sensory)
Posterior Division (sensory
-auriculotemporal n.
- lingual n.,
-inferior alveolar n.
>nerve to mylohoid
MOTOR AND SENSORY A
Supply to:
Motor = mylohyoid m., anterior belly of the digastric m.; tensor tympani m., tensor veli palatini m.; muscles of mastication (temporalis, masseter, medial pterygoid and lateral pterygoid)
Sensory = skin of the lower lip and jaw extending superiorly above level of the ear; mucous membrane of the tongue and floor of the mouth; lower teeth and gingiva of the mandibular alveolar arch
Location: passes through the Foramen Ovale to exit the middle cranial fossa; the otic ganglion is associated with the medial side of V3 below the foramen ovale; the auriculotemporal n. carries postganglionic parasympathetic axons to the parotid gland; the submandibular ganglion is associated withe the lingual n. near the submandibular gland; postganglionic parasympathetics from the submandibular ganglion supply the submandibular gland and the sublingual gland
Facial Nerve (CN-VII)
Cranial Nerve 7
Derivatives of 2nd Brachial (Pharyngeal) arch
Origin: pons
nucleus solitarius of medulla via nervus intermedius (sensory root) from geniculate ganglion; Superior Salivatory nucleus (preganglionic parasympathetic) of pons via nervus intermedius; facial motor nucleus of pons via motor root
Branches:
(In Tympanic Cavity/Inside Skull Region)
- Greater petrosal n. (preganglionic parasympathetic to pterygopalatine ganglion, postganglionic parasympathetic travels with brs. of maxillary division of trigeminal)
- Chorda tympani (taste from anterior 2/3 of the tongue; preganglionic parasympathetic to the submandibular ganglion, postganglionic parasympathetic to the submandibular and sublingual glands)
- n. to stapedius
The big motor branch of the facial nerve enters the internal accoustic meatus –> facial canal –>
emerges on the face through the STYLOMASTOID foramen –> travels through the parotid
gland –> gives two divisions w/in the parotid gland TEMPOROFACIAL AND CERVICOFACIAL
which further divide into even more branches
Branches on Face: temporal - zygomatic - buccal -marginal mandibular -cervical -posterior auricular -posterior belly of digastric n.
BOTH SENSORY AND MOTOR; PARASYMPATHETIC, AND TASTE
Supply to: Motor = stapedius m., stylohyoid m., posterior belly of digastric m., ALL muscles of facial expression
Secretomotor = to lacrimal, submandibular, sublingual, and mucous glands of the nasal and oral cavities
Taste = anterior 2/3 of the tongue; part of the skin of the external auditory meatus
Location: exits the posterior cranial fossa by passing into the internal acoustic meatus, goes through the facial canal; exits the skull at the stylomastoid foramen
Vestibulocochlear Nerve (CN-VIII)
Cranial Nerve 8
SENSORY ONLY
Hearing
Origin: pons: vestibular nuclei from the vestibular ganglion of the semicircular ducts; spiral ganglion of cochlea
Branches: Divides within the temporal bone into vestibular and cochlear part
-vestibular: balance/proprioception
- cochlear: hearing
Location: passes into the internal auditory meatus
Glossopharyengeal Nerve (CN-IX)
Cranial Nerve 9
Derivative of 3rd Branchial Arch (only 1 muscle = stylopharyngeus)
Origin: medulla:
nucleus solitarius from the inferior ganglion; nucleus ambiguus; inferior salivatory nucleus (preganglionic parasympathetic)
Branches:
- Tympanic nerve to the tympanic plexus
- Lesser petrosal n.,
- Carotid sinus n.
- Stylopharyngeus branch
- Pharyngeal branches (afferent supply to the pharyngeal plexus)
Supply to: MOTOR = stylopharyngeus; cell bodies located in nucleus ambiguus
SECRETOMOTOR: to the parotid gland (preganglionic parasympathetic via the tympanic n. to the lesser petrosal n. to the otic ganglion; postganglionic parasympathetic via the auriculotemporal n. of V3
SENSORY: carotid body, carotid sinus, pharynx, middle ear; skin of the external ear; sensory part of PHARYGEAL PLEXUS
TASTE: posterior 1/3 of the tongue; inferior surface of soft palate
Location: exits the posterior cranial fossa by passing through the jugular foramen; it may penetrate the stylopharyngeus m.
Vagus Nerve (CN-X)
Cranial Nerve 10:
Derivative of 4th and 6th Brachial Arches
Origin: medulla: dorsal motor nucleus inferior ganglion; nucleus ambiguus; superior ganglion; inferior ganglion
Branches
- auricular (mastoid canaliculus in the lateral wall of the jugular foramen)
-pharyngeal br., (Pharyngeal plexus)
-superior laryngeal,
>internal laryngeal (pierces the thyroid cartilage; sensory larynx)
>external laryngeal (motor to circothyroid)
-recurrent laryngeal n.,
IN THORAX
**anterior vagal trunk = LEFT vagus
**posterior vagal = RIGHT vagus
MOTOR, SENSORY, PREGANGLIONIC PARASYMPATHETICS, VISERAL SENSORY, TASTE
Supply to:
MOTOR = Intrinsic muscles of the larynx, pharynx (except stylopharyngeus), and palate (except tensor veli palatini (V3) )
SENSORY = skin of the external auditory meatus viscera of head, neck, thorax & abdomen proximal to the left colic flexure
TASTE: epiglottis and root of tongue
Location: passes through the jugular foramen to exit the posterior cranial fossa; vagus means “wanderer” in reference to its extensive distribution to the body cavities
Accessory Nerve (CN-XI)
Cranial Nerve 11
Origin: medulla - nucleus ambiguus; spinal root: spinal nucleus of the upper cervical spinal cord
MOTOR ONLY
Supply to: sternocleidomastoid and trapezius mm
Location: passing through the foramen magnum; exits skull by passing through the jugular foramen
Hypoglossal Nerve (CN-XII)
Cranial Nerve 12
Origin: medulla: hypoglossal nucleus
MOTOR ONLY
Supply to: intrinsic and extrinsic muscles of the tongue (except the palatoglossus m. (cn-ix pharyngeal plexus)
Location: exits the posterior cranial fossa by passing through the hypoglossal canal; the superior root of the ansa cervicalis travels with the hypoglossal n. for a short distance;
arise between the olive and the pyramid of medulla;
passing posterior to the internal carotid artery and the glossopharyngeal and vagus nerves.
it then passes inferiorly sandwiched between the internal jugular vein and the internal carotid artery. It then loops forward over the occipital artery
travels lateral to hypoglossus m. on the way to tongue
Middle Superior Alveolar Nerve
Branch of: Infraorbital n. < Maxillary n (V2) < Trigeminal
Supply to: maxillary premolar teeth and gingiva; maxillary sinus
Middle Superior Alveolar artery may be absent in some people
Posterior Superior Alveolar Nerve
Branch of Maxillary n (V2)
Supply to: maxillary molar teeth and gingiva; (specifically 3rd molar, 2nd molar, and distal root of 1st maxillary molar); maxillary sinus
Location: posterior superior alveolar n. enters bone by passing through the small foramina on the posterior surface of the maxilla (maxillary tuberosity) and branches off the maxillary before it enters the pterygomaxillary fissure which connects Intertemporal Fossa to Pterygopalatine Fossa (travles from PPF to ITF with a.)
Ansa Cervicalis
Part of Cervical Plexus (C1 - C4)
Made up specifically of C1-C3 fibers
Descendens Hypoglossi/superior root (C1 and C2)
Descendens Cervicalis/inferior root (C2 and C3)
ALL MOTOR
Supply to: Infrahyoid muscles:
- Superior/Inferior belly of Omohyoid m
- Sternohyoid m.,
- Sernothyroid m.,
Location: A part of the cervical plexus which is in the floor OF THE POSTERIOR TRIANGLE OF THE NECK halfway up the sternocleidomastoid muscle, and within the prevertebral layer of cervical fascia.
