What causes facial twitching and how is it treated?

Causes and Treatment of Facial Twitching

Facial twitching is most effectively treated with botulinum toxin injections for persistent cases, while addressing the underlying cause is essential for successful management. 1

Common Causes of Facial Twitching

Facial twitching can result from various conditions:

• Bell's palsy: Acute unilateral facial nerve paresis/paralysis with onset in less than 72 hours 1
• Hemifacial spasm: Intermittent, unilateral, spasmodic contractions of facial muscles innervated by the facial nerve 2
• Tardive dyskinesia: Side effect of antipsychotic medications 1
• Other causes:
  • Paroxysmal Kinesigenic Dyskinesia (PKD)
  • Cerebellopontine angle lesions
  • Brainstem pathology
  • Temporal bone disorders
  • Parotid tumors 1
  • Vascular compression of facial nerve (most common cause of hemifacial spasm) 3
  • Post-Bell's synkinesis
  • Dystonia
  • Psychogenic conditions 4

Diagnostic Red Flags Requiring Immediate Evaluation

• Facial numbness or weakness
• Other neurological symptoms
• Bilateral involvement
• Progressive symptoms
• Associated hearing loss or tinnitus 1

Diagnostic Approach

1. Clinical presentation assessment:

   • Unilateral vs. bilateral involvement
   • Tonic vs. clonic contractions
   • Distribution of affected muscles
   • Associated symptoms 1

2. Imaging studies:

   • MRI: Preferred for evaluating facial nerve course and potential compression
   • High-resolution CT of temporal bone: Complementary to MRI for evaluating osseous integrity 1

Treatment Algorithm

First-line Treatment

Botulinum toxin injections are the treatment of choice for persistent facial twitching, particularly hemifacial spasm:

• High efficacy with few disabling side effects 1, 2
• Administered no more frequently than every three months 5
• Typical dose: 4 Units per injection site 5
• Proper technique is essential to avoid complications like eyelid ptosis 5

Treatment Based on Underlying Cause

1. For Bell's palsy:

   • Oral corticosteroids within 72 hours of symptom onset
   • Antiviral therapy may be considered in combination with steroids (minimal additional benefit)
   • Eye protection for incomplete eyelid closure (artificial tears, ocular ointment, eye patching) 1

2. For Paroxysmal Kinesigenic Dyskinesia:

   • Anticonvulsant medications 1

3. For structural causes:

   • Treatment directed at underlying condition (tumor removal, vascular decompression) 1

4. For tardive dyskinesia:

   • Assess for abnormal movements every 3-6 months using the Abnormal Involuntary Movement Scale
   • Consider medication adjustment if caused by antipsychotics 1

Important Precautions with Botulinum Toxin

• Not interchangeable: Units of JEUVEAU (prabotulinumtoxinA-xvfs) are specific to the preparation and cannot be converted to units of other botulinum toxin products 5

• Proper administration technique:

  • Avoid injection near the levator palpebrae superioris
  • Place lateral corrugator injections at least 1 cm above the bony supraorbital ridge
  • Avoid injecting closer than 1 cm above the central eyebrow 5

• Contraindications:

  • Known hypersensitivity to botulinum toxin
  • Infection at injection site 5

• Warning - Spread of toxin effect:

  • Symptoms may include asthenia, muscle weakness, diplopia, ptosis, dysphagia, dysphonia, dysarthria
  • Seek immediate medical care if swallowing, speech, or respiratory difficulties occur 5

Prognosis

• Bell's palsy: 70-94% chance of complete recovery, depending on severity 1
• Hemifacial spasm: Typically chronic but controllable with botulinum toxin 1, 6
• Secondary causes: Prognosis depends on the underlying condition 1

Follow-up Recommendations

Patients should be reevaluated if symptoms worsen or don't improve after 3 months 1