Paediatric Bell’s Palsy Paediatric Update November 2014

Richard Webster, Paediatric Neurologist

Children’s Hospital at Westmead

Typical history

Unilateral LMN facial weakness

Acute onset

– over a day or two

– progressive worst within 2-4 weeks

Preceding ear canal pain

Recovery of function

– starts within 3 weeks

– resolution within 6 months

Definition Bell’s palsy

Acute idiopathic peripheral facial nerve palsy

– 1. Assessment

– 2. Differential diagnosis

– 3. Treatment

– 4. Monitoring

..but first some anatomy

Facial nerve motor nucleus

– Lower pons

– Fibres of VIn curve around the VIIn nucleus

– Bilateral supranuclear inputs for upper face control

Facial nerve

– Leaves pontomedullary junction

– Sensory/autonomic fibres join in facial canal

– Passes through the facial canal

Facial nerve anatomy

Functions of facial nerve – 1. Facial expression

– 2. Lacrimal gland – greater petrosal nerve

– 3. Nerve to stapedius

– 4. Taste fibres to anterior 2/3 tongue (chorda tympani)

– 5. Sensation external auditory meatus

– 6. Salivation – (chorda tympani)

1. Assessment: facial expression

1. Observe

2. Look up

3. Eye closure

4. Muscles of facial expression

– Smile – emotional/voluntary

– Blow out cheeks – lip closure

5. Platysma

– Difficult

Bell’s palsy algorithm? Facial palsy?

LMN UMN

Face assessment

1. What is weak?

– One side or both sides

– Is it all consistent with VIIn?

2. Is the forehead involved?

– UMN lesions spare the forehead

– Get the child to look up

1. Where in the nerve is the lesions?

1. Dry eye?

2. Hyperacusis?

3. Loss of taste (difficult in most children) ant 2/3 of tongue

4. Test for auricular sensation

Bell’s palsy algorithm Facial palsy?

LMN UMN

Neurological exam

Isolated Other signs

Is this isolated facial n palsy?

Cranial nerves

– II – papilloedema

– VI + gaze – nuclear lesions

– VIII – hearing

– IX, X – swallowing, palate

– XI,XII

Cerebellum

Long tract signs

Gait

Neurological differential diagnosis

1. Nerve disease

– Infiltration

– Inflammation/infection

– Compression – bone/neoplasm

2. Muscle disease

– Myasthenia

Case

8 yo girl with R LMN VII weakness

– Gradual onset

Treated with steroids for 1/52 no improvement then given a second course

No improvement within 3 weeks

Then developed unsteady gait

– Limitation of eye movement to right

– Deviates to right on tandem gait

Bell’s palsy algorithm Facial palsy?

LMN UMN

Neurological exam

Isolated Other signs

Examination/Ix

No cause

BP - hypertension FBC - leukaemia Middle Ear- OM/mastoiditis, Herpes

Further examination

Check ears

– ? Otitis media

– ? Evidence of vesicles (Ramsay Hunt)

Systemic examination

– BP

– Hepato-splenomegaly/pallor

FBC – evidence of leukaemia

Warning signs

Young age

Bell’s palsy uncommon in infants and young children

3/100,000 < 10, 25/100,00 adults

Malignancy/ diseases predisposing to

malignancy

History of recurrent otitis media

Syndromes associated with facial

dysmorphism

Bell’s palsy algorithm Facial palsy?

LMN UMN

Neurological exam

Isolated Other signs

Examination/Ix

No cause

BP - hypertension FBC - leukaemia Middle Ear- OM/mastoiditis, Herpes

Treat

3. Treatment

Eye protection

– Avoid corneal abrasions if the patient with facial palsy is unable to close the eye.

– Artificial tears during the day

– Ointment at night

– Eye patch if needed

Treatment

Steroids

– No definite evidence but strong adult data

– Prednisolone 2mg/kg/day (max 60-80mg)

– Give for 5 days and then taper for 5 days

– (Up to date)

Bell’s palsy algorithm Facial palsy?

LMN UMN

Neurological exam

Isolated Other signs

Examination

No cause

BP - hypertension FBC - leukaemia Middle Ear- OM/mastoiditis, Herpes

Treat

Review

4. When to review?

Review

– 1 week after diagnosis

– Weekly until clear improvement

– Follow-up to make sure of resolution

Imaging/referral

Unusual history

– Slow onset

Progression beyond 3 weeks

Failure to improve after 4 weeks

Associated history/signs suggesting a more sinister cause for Bell’s palsy