Facial Nerve Flashcards
Origin
It is a mixed nerve arising by 3 nuclei:
1. Sensory
2. Motor
3. Parasympathetic
Motor
In pons
Parasympathetic
Is nervus intermedius
Superior salivary nucleus in pons
Sensory
Is nervus intermedius
Solitary nucleus in medulla
Course inside skull
- It arises from pons
- Passes lateral through internal auditory meatus
- Enter facial canal
- Passes backwards on middle ear medial wall then downwards on its posterior wall
- Leaves skull via Stylomastoid foramen
Course outside skull
- Curves around styloid process
- Enter parotid Posteromedial surface
- Passes superficial to posterior facial vein and ECA
- Divides into 5 terminals
Branches
Inside petrous bone:
1. Greater superficial petrosal
2. Nerve to Stapedius
3. Chorda tympani
Just outside skull:
1. Posterior auricular
2. Branch to posterior belly digastric and Stylohyoid
In face (inside parotid gland):
1. Temporal
2. Zygomatic
3. Buccal
4. Mandibular
5. Cervical
Chorda tympani
- Arises on facial canal vertical part (6mm above Stylomastoid foramen)
- Passes forwards via tympanic membrane
- Leave middle ear via pterotympanic fissure
- Enters Infratemporal fossa
- Joins lingual nerve deep to lateral pterygoid at acute angle to be distributed with its branches
Chorda tympani supply
- Taste
- Parasympathetic
Taste
To anterior 2/3 tongue
Parasympathetic chorda tympani
To
1. Submandibular gland
2. Sublingual gland
After relaying in submandibular ganglion
Branches outside the skull
Emerge from stylomastoid foramen
Posterior auricular nerve
To occipital belly of occipitofrontalis
Terminal branches
Supply muscles of:
1. Scalp
2. Face
3. Platysma
Facial nerve
7th cranial nerve