7.4 Cranial Nerve VII (Facial) Palsy

Cranial Nerve VII palsies may require the candidate to determine:

1. The location of the neurological lesion, and exclude life-threatening causes
2. The oculoplastic management to a multi-factorial problem

Examination Outline

Examination Structure

1. Visual Acuity (Best Corrected)

2. Inspection

  1. Facial asymmetry
    1. Loss of forehead wrinkles (lower motor neurone CNVII palsy)
    2. Brow ptosis (not blepharoptosis) / Lid retraction & Superior sclera [iii]
    3. ↓ Blink “Please blink” Twitch of mouth = aberrant regeneration
    4. Ectropion (paralytic) / Inferior scleral show / Red eye
    5. Loss of nasolabial fold
    6. Drooping angle of the mouth
  2. Scars / masses (behind ear, parotid, lymphadenopathy)
  3. Esotropia (CNVI

Check MRD1 if considering a gold weight

Figure 7.4.1 Right Lower Motor Neurone CNVII Palsy

Figure 7.4.1
Right Lower Motor Neurone CNVII Palsy

Note the loss of forehead wrinkles (hence LMN palsy), brow ptosis, paralytic ectropion and less prominent nasolabial fold.

3. Dynamic Testing


Instruction to Patient

Examiner Task

i. Temporal

Instruction to Patient

“Look up”

Examiner Task

Try to push down

ii. Zygomatic + Bells

Instruction to Patient

“Close your eyes as tight as you can”

Examiner Task

Try to open

iii. Buccal

Instruction to Patient

“Puff out your cheeks”

Examiner Task

Push in

iv. Mandibular

Instruction to Patient

“Grin like a gorilla / Show me your teeth”

Examiner Task

Narrow inter-palpebral fissure = aberrant regeneration

v. Cervical (platysma)

Instruction to Patient

“Stretch your neck as if shaving”

Examiner Task

Crocodile tears [iv] = aberrant regeneration

The fibres that originally innervated the submandibular / sublingual glands now innervate the lacrimal gland via the greater petrosal nerve

4. Assess Risk of Exposure

i. Bells Phenomenon
  • Firmly but gently grip both upper eyelids with your thumbs to prevent closing. Ask the patient to “Close your eyes”. With an upward Bells phenomenon, the globes rotate up and out
ii. Lagophthalmos

(2° to upper lid orbicularis dysfunction, unopposed levator)

  • Ask the patient to “Rest your head back and gently close your eyes as if you are going to sleep”. Assess whether there is an opening between the upper and lower eyelids- if so, measure this with a ruler
iii. Facial / Corneal Sensation (CN V)
  • Ask the examiner for corneal sensation - under examination conditions you will usually be told the result
iv. Dry Eye and Corneal Exposure
  • Stain the tear film with fluorescein and examine with a slit lamp for punctate stain

5. CN VI

  • Check abduction


Test hearing (use 512 Hz tuning fork):

  • Hyperacusis = loss of dampening function of stapedius
  • Deafness = consider CPA tumour

Check the ears:

  • Vesicles in external auditory canal = Ramsay-Hunt
  • SCC behind ear = infiltrate facial nerve

7. Parotid

  • Palpate for tumours
  • Check regional lymph nodes

8. Slit-Lamp Exam

  • Corneal exposure?

9. Fundoscopy

  • Papilloedema?

10. Hemiplegia

  • Strength
  • Cerebellar function – finger-nose


  • Unilateral or bilateral
  • Upper vs. lower motor neuron
  • Aberrant regeneration
  • Corneal exposure (Paralytic ectropion? Neurotrophic cornea?)
  • CNVI / VIII involvement
  • Ramsay-Hunt


Figure 7.4.2 CNVII Pathways

Figure 7.4.2
CNVII Pathways

Upper versus Lower Motor Neurone CNVII Palsies

  • Upper Motor Neurone (e.g. CVA)
    • Spastic paralysis of contralateral lower face
    • (Sparing of frontalis & some orbicularis- bilateral innervation)
    • Can raise eyebrows
  • Lower Motor Neurone (e.g. Bells palsy)
    • Flaccid paralysis of ipsilateral side of face
    • Can’t raise eyebrow on affected side
Figure 7.4.3 Upper versus Lower Motor Neurone CNVII Palsies

Figure 7.4.3
Upper versus Lower Motor Neurone CNVII Palsies

Upper Motor Neurone lesions produce spastic paralysis of the contralateral lower face. The forehead is unaffected because this has bi-cortical innervation.
Lower Motor Neurone lesions produce flaccid paralysis of the ipsilateral side of the face


1. Idiopathic

  • Bell’s palsy is a diagnosis of exclusion and may be related to viral infection (e.g. HSV)
  • ⅔ of unilateral CNVII palsy
  • Develops over hours
  • Unilateral mastoid pain is often present
  • 85% get satisfactory recovery by 3 months
  • Consider MRI if no improvement

2. Trauma / Surgery

  • e.g. parotid

3. Infection

  • Ramsay-Hunt syndrome (VZV) – external acoustic meatus (EAM) vesicles, deafness, vertigo
  • Chronic otitis media
  • Chronic meningitis (TB, Sarcoidosis)
  • HIV

4. Immunological

  • MS
  • Guillain- Barré syndrome

5. Neoplastic

  • Cerebellopontine Angle CPA (acoustic neuroma, nasopharyngeal cancer, cholesteatoma)
  • Parotid Cancer
  • SCC with perineural spread

6. Metabolic

  • Diabetes
  • Paget’s disease

Causes of Bilateral CNVII palsy

  1. Myaesthenia gravis / Guillain-Barré
  2. Sarcoidosis
  3. NF-2 (bilateral acoustic neuromas)
  4. Mobius syndrome
  5. Basilar meningitis

Causes of CNVII Palsy by Location

i. Upper Motor Neurone
  1. CVA
  2. Tumour
  3. Infection
  4. Demyelination (MS)
ii. Lower Motor Neurone

Brainstem (Pons)


  1. CVA
  2. Tumour
  3. Infection
  4. Demyelination (e.g. MS)

Associated Features

  1. CN V palsy (↓ Corneal sensation)
  2. CN VI palsy (Diplopia)
  3. Long-tract signs


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