Facial Nerve Flashcards
What are the 4 nuclei situated in lower pons
Motor nucleus
Superior salivatory nucleus
Lacrimatory nucleus
Nucleus of tractus solitarius
Where does the facial nerve arise from
Junction of pons and medulla (brain stem)
What are the 3 branches given off the facial canal
Greater petrosal nerve
Nerve to stapedius
Chorda tympani
What does the greater petrosal nerve do
Parasympathetic fibres to mucous glands and lacrimal gland
What does the nerve to stapedius do
Motor fibres to stapedius muscle of middle ear
What does the chorda tympani do
Special sensory fibres to anterior 2/3 tongue and parasympathetic fibres to submandibular and sublingual glands
What foramen does the facial nerve exit the cranium from
Stylomastoid foramen
What is the name of the ganglion formed by the two roots fused in the cranium
Geniculate ganglion
What are the 3 branches given off once the facial nerve exits the foramen
Posterior Auricular nerve
Nerve to posterior belly of digastric muscle
Nerve to stylohyoid muscle
What does the posterior Auricular nerve do
Innervates intrinsic and extrinsic muscles of the outer ear, occipital part of Occipitalfrontalis
What does the nerve to posterior belly of digastric muscle do
Responsible for raising hyoid bone
What does the nerve to stylohyoid muscle do
Responsible for raising hyoid bone
Why is the facial nerve vulnerable to trauma and inflammatory changes
Has the longest passage through bony canal of any nerve in body
On emerging from stylomastoid foramen what function does the facial nerve have
Entirely motor
What happens when the facial nerve reaches the parotid gland
It terminates by dividing into five terminal motor branches
What does the temporal branch do
Innervates frontalis, orbicularis oculi and Corrugator supercilii
What does the zygomatic branch do
Innervates orbicularis oculi
What does the buccal branch do
Innervates orbicularis oris, Buccinator and zygomaticus
What does the marginal mandibular branch do
Innervates depressor labii inferioris, depressor anguli oris and mentalis
What does the cervical branch do
Innervates Platysma
What ganglion is on the greater petrosal nerve
Pterygopalatine ganglion
What do the muscles of facial expression all develop from
Second pharyngeal arch
What are the 2 muscles in the orbital group
Orbicularis oculi
Corrugator supercilii
What are the 3 muscles in the nasal group
Nasalis
Procerus
Depressor septi nasi
What are the 3 muscles in the oral group
Orbicularis oris
Buccinator
Minor oral muscles - act on lips and mouth
What 3 muscles are in the lower group of the minor oral muscles
Depressor anguli oris
Depressor labii inferioris
Mentalis
What are the 6 muscles in the upper minor oral muscle group
Risorius
Zygomaticus major
Zygomaticus minor
Levator labii superioris
Levator labii superioris alaeque nasi
Levator anguli oris
What does damage to the upper motor neurons of the facial nerve result in
Contra lateral lower facial weakness
How do the facial muscles of contralateral side display
Axons of upper motor neurons of facial nerve cross midline of brain stem
What is the location of the upper motor neuron lesion
Motor cortex, connection from motor cortex to facial nucleus in pons
Above the facial nucleus
Which side is affected by an upper motor neuron lesion
Contralateral
Which muscle are affected by an upper motor neuron lesion
Lower muscles of facial expression
What is the location of a lower motor neuron lesion
Facial nucleus anywhere along the facial nerve below the facial nucleus
Which side is affected by a lower motor neuron lesion
Ipsilateral
Which muscles are affected by a lower motor neuron lesion
Upper and lower muscles of facial expression
Which type of lesion affects the forehead
Lower motor neuron lesion
What type of symptoms can occur with a lower motor neuron lesion
Incomplete eye closure (dry eyes, corneal ulceration), hyperacusis, loss of taste sensation to anterior tongue
What are the 2 branches which form the facial nerve
The motor root of facial nerve and nervus intermedius
What does the geniculate ganglion contain
Cell bodies of tase afferents
Where is the geniculate ganglion
At the site of turn when the facial nerve makes a sharp posterior turn (the Genu) to run posteriorly and medially across medial wall of middle ear cavity
In the petrous temporal bone what are the 2 preganglionic parasympathetic branches given off
Greater superficial petrosal nerve and chorda tympani
Where does the greater superficial petrosal nerve arise from
The geniculate ganglion
What does the greater superficial petrosal nerve pass through
The greater superficial petrosal foramen
What is the parasympathetic function of the greater superficial petrosal nerve
Secretomotor innervation of lacrimal gland and small glands of nose and palate
What is the special sensory function of the greater superficial petrosal nerve
Taste innervation of palate
When does the chorda tympani leave the facial nerve
After geniculate ganglion
What nerve does the chorda tympani join as it passes downward and forwards
The lingual nerve
What is the parasympathetic function of the chorda tympani
Secretomotor innervation of submandibular and sublingual glands
What is the special sensory function of the chorda tympani
Taste innervation of anterior 2/3 of tongue
What are the parasympathetic synapses of the cranial ganglia of the facial nerve
Nicotinic and muscurinic
What are the sympathetic synapses of the cranial ganglia in the facial nerve
Nicotinic and adrenergic
What are the 4 parasympathetic ganglia
Ciliary
Pterygopalatine
Otic
Submandibular
Which parasympathetic ganglia is occulomotor
Ciliary
Which parasympathetic ganglia is otic
Glossopharyngeal
Which parasympathetic ganglia are facial
Pterygopalatine
Submandibular
What is the location of the ciliary ganglion
Posterior orbit
What is the sympathetic nerve of the ciliary ganglion
Internal carotid plexus
What is the sensory nerve of the ciliary ganglion
Opthalmic branch of trigeminal
What is the sensory function of the ciliary
Autonomic feedback from eyeball
What is the parasympathetic function of the ciliary
Sphincter pupillae muscle
Ciliary muscle
What is the sympathetic function of the ciliary
Dilator pupillae muscle
Blood vessels of eye
What is the sensory function of the Pterygopalatine
Mucosa of nasal cavity
Paranasal air sinuses
Superior pharynx
Hard and soft palates
What is the parasympathetic function of the Pterygopalatine
Lacrimal grand via zygomatic nerve
Mucous glands of nasal cavity
Paranasal air sinuses
Superior pharynx
Hard and soft palates
What is the sympathetic function of the Pterygopalatine
Lacrimal gland and glands and vessels of nasal cavity
Paranasal air sinuses
Superior pharynx
Hard and soft palates
What is the sensory function of the otic
Autonomic feedback from parotid gland
What is the parasympathetic function of the otic
Parotid gland via auriculotemporal nerve
What is the sympathetic function of the otic
Parotid gland and its blood vessels
What is the sensory function of the submandibular
Autonomic feedback from submandibular and sublingual glands and minor glands of floor of mouth
What is the parasympathetic function of the submandibular
Submandibular and sublingual glands and minor glands of the floor of the mouth
What is the sympathetic function of the submandibular
Submandibular and sublingual glands
Minor glands of floor of the mouth and glandular vessels
What syndrome occurs due to injury of the auriculotemporal nerve
Frey syndrome
