16/04/2021
Facial Palsy
♿Introduction
Facial palsy is due to the damage in the facial nerve that supplies the muscles of the face. It can be categorized into two based on the location of casual pathology:
1️⃣Central facial palsy- due to damage above the facial nucleus.
2️⃣Peripheral facial palsy-due to damage at or below the facial nucleus.
⚛️Clinically Relevant Anatomy
The VIIth cranial Nerve has its nucleus in the Pons and takes a rather winding route before exiting the skull through the stylomastoid foramen. It then passes through the parotid gland, splitting into 5 branches:
★ Temporal.
★zygomatic.
★buccal.
★mandibular.
★cervical.
♿Clinical Presentation
Paralysis of the muscles supplied by the Facial Nerve presents on the affected side of the face as follows:
🗣️Appearance and Range of Movement:
🏃Inability to close the eye
🏃Inability to move the lips eg. into a smile, pucker
🏃At rest, the affected side of the face may "droop"
🏃The lower eyelid may drop and turn outward - "ectropion"
🗣️Functional Effects:
🏃Difficulty eating and drinking as lack of lip seal makes it difficult to keep fluids and food in the oral cavity
🏃Reduced clarity of speech as the "labial consonents" (ie. b, p, m, v, f) all require lip seal
🏃Dryness of the affected eye.
🗣️Somatic Effects:
🏃The facial nerve supplies the lachrymal glands of the eye, the saliva glands, and to the muscle of the stirrup bone in the middle ear (the stapes). It also transmits taste from the anterior 2/3 of the tongue.
🏃Hyperacusis = sensitivity to sudden loud noises
🏃Altered taste sensation.
