AN28.1-10 | Face & parotid region — Summary & Reflection

REFLECT

Draw the path of the facial nerve (CN VII) from the pons to the five terminal branches. At each landmark, note which function would be lost if the nerve were damaged at that point. How does this help you localise a lesion in a patient with facial palsy?

KEY TAKEAWAYS

Face & Parotid Region — Key Points:

1. Facial expression muscles = 2nd pharyngeal arch = all supplied by CN VII. Frontalis has bilateral cortical representation (spared in UMN palsy).
2. Facial nerve branches: Temporal, Zygomatic, Buccal, Marginal mandibular, Cervical ("To Zanzibar By Motor Car"). Exits via stylomastoid foramen.
3. Face sensory = CN V: V1 (ophthalmic) → forehead; V2 (maxillary) → cheek/upper lip (infraorbital foramen); V3 (mandibular) → chin/lower lip (mental foramen).
4. Facial artery: ECA origin → hooks at lower mandible border → terminates as angular artery at medial canthus. Tortuous course; anastomoses with ICA at medial eye angle.
5. Facial vein is valveless — retrograde spread of infection to cavernous sinus possible. Deep facial vein = second route via pterygoid plexus.
6. Lymph drainage: Submandibular nodes receive most of the face; all drain to deep cervical (jugular chain).
7. Parotid gland: Contains ECA (deepest) → retromandibular vein → CN VII (most superficial). Duct (Stensen's) opens opposite upper 2nd molar.
8. Frey's syndrome: Post-parotidectomy gustatory sweating — aberrant parasympathetic regeneration into sweat gland sympathetics.