Facial Nerve Flashcards
What is the attachment of the facial nerve?
Lateral surface of brainstem, between pons and medulla oblongata
What are the 3 parts which make the facial nerve a mixed nerve?
- Motor
- Sensory
- Parasympathetic
Where is the sensory root of the facial nerve located?
Medulla oblongata
Where is the motor root of the facial nerve located?
Pons
What are the two roots of the facial nerve?
- Small sensory root
2. Large motor root
How do the motor and sensory roots of the facial nerve leave the cranial cavity?
Internal acoustic meatus
What is the function of the motor part of the facial nerve?
Control muscles of facial expression
What is the function of the parasympathetic part of the facial nerve?
Control lacrimal, submandibular and sublingual glands
What is the function of the sensory part of the facial nerve?
Detect taste in anterior 2/3 of the tongue
Describe the course of the facial nerve after entering the internal acoustic meatus
Passes through facial canal in petrous part of temporal bone
Where does the facial nerve emerge from?
Base of the skull through the stylomastoid foramen
Where does the facial nerve go after it emerges from the base of the skull?
Transverses parotid gland
What 3 branches are given off the facial nerve within the facial canal?
- Greater petrosal
- Nerve to stapedius muscle
- Chorda tympani nerve
What 3 branches are given off the facial nerve just below stylomastoid foramen?
- Nerve to post. belly of digastric
- Nerve to stylohyoid muscle
- Posterior auricular nerve
What 5 branches are given off the facial nerve after piercing the parotid gland?
- Temporal
- Zygomatic
- Buccal
- Mandibular
- Cervical
Where does the greater petrosal nerve arise?
The nerve at the geniculate ganglion
What nerve is formed when the greater petrosal nerve meets the deep petrosal nerve?
Nerve of pterygoid canal
What are the 2 parts of the facial motor nucleus?
- Dorsal
2. Ventral
Describe the dorsal part of the facial motor nucleus
Receives corticonuclear fibres from both sides of the body
Describe the ventral part of the facial motor nucleus
Receives corticonuclear fibres from the opposite side of the body only
What is a clinical example of an upper motor neuron lesion?
Stroke
What is a clinical example of an lower motor neuron lesion?
Bell’s palsy
What is the result of a UMNL?
Paralysis of muscles in lower face on opposite side
What is the result of a LMNL?
Paralysis of upper and lower parts of the face on the same side
What are 4 ways facial nerve paralysis can physically affect a person?
- Wrinkles of forehead disappear
- Unable to close eyelids
- Angle of mouth drops
- Accumulation of food in the vestibule
