Cranial Nerves

Question 1

What is the pathway of the facial nerve?

Answer 1

originates at the pons/medulla junction in the brainstem
passes through the internal acoustic meatus to leave cranial cavity
goes through the facial canal in the temporal bone
exits the skull through the stylomastoid foramen

Question 2

Branches of the facial nerve

Answer 2

3 muscular nerves, posterior auricular, posterior digastric &stylohyoid nerve. then 5 motor branches including temporal, zygomatic, buccal, mandibular and cervical. also, two large mixed branches that include chorda tympani and greater petrosal nerve

Question 3

what are the branches for cranial nerve V (trigeminal)

Answer 3

Ophthalmic, Maxillary & Mandibular.

Question 4

cranial nerve VII (facial) branches of facial expression and muscles

Answer 4

-temporal branch/ superior orbicularis oculi
-zygomatic branch/ zygomaticus major
-buccal branch/ buccinator
-mandibular branch/ mentalis
-cervical branch/ platysma

Question 5

Branches of maxillary nerve (CNV) (V2) and areas of supply

Answer 5

Zygomatic formed by the zygomaticofacial (skin of cheek) and zygomaticotemporal (skin of temporal region) also sends post-ganglionic parasympathetic (motor) fibres to the lacrimal gland
Infraorbital supplies skin of upper lip. medial portion of cheek, lower eyelid and side of nose. branches to anterior superior alveolar (ASA) and middle superior alveolar (MSA). ASA supplies 13-23, periodontium and buccal tissue. MSA supplies maxillary premolars and MB root of maxillary first molar, sinus mucosa, periodontium and buccal gingiva
Nasopalatine supplies anterior hard palate, maxillary anterior teeth and tissue of nasal septum
Greater palatine supplies posterior hard palate and posterior palatal gingiva. Lesser palatine supplies soft palate and palatine tonsils
Posterior superior alveolar (PSA) supplies maxillary molars, maxillary sinus, periodontium and buccal gingiva

Question 6

Name a condition affecting the facial nerve (CNVII). Include cause, symptoms and treatment

Answer 6

Bell’s Palsy is rapid, unilateral facial paralysis, cause is unknown. Could be due to inflammation or a viral infection. Treatment can include anti-inflammatory corticosteroids or physical therapy

Question 7

Name a condition affecting the trigeminal nerve (CNV). Include cause, symptoms and treatment

Answer 7

Trigeminal Neuralgia (tic douloureux) is nerve pain due to compression by an artery, inflammation, or degeneration of the trigeminal nerve. Cause is unknown. Intense facial pain, like an electric shock and facial spasms. Mostly unilateral, more RHS. Treatment includes anticonvulsants, botox and alcohol injections.

Question 8

Chorda Tympani Nerve?

Answer 8

carries pre and post-ganglionic parasympathetic (motor) fibres to submandibular and sublingual salivary glands.
sensory nerve for taste sensation to body (anterior 2/3rds) of the tongue

Question 9

Greater Petrosal Nerve

Answer 9

carries pre-ganglionic parasympathetic (motor) fibres for the lacrimal gland to the pterygopalatine ganglion. post-ganglionic fibres to the lacrimal gland via zygomatic and lacrimal nerves.
sensory fibres for taste sensation in the palate