What causes facial twitching and how is it treated?

Causes and Treatment of Facial Twitching

Facial twitching refers to involuntary muscle contractions affecting the face, which can have various underlying causes ranging from benign to serious neurological conditions. The most effective treatment for facial twitching depends on the specific underlying cause, with botulinum toxin injections being the first-line treatment for hemifacial spasm and other persistent facial dyskinesias. 1

Common Causes of Facial Twitching

Benign Causes

• Bell's Palsy: Acute unilateral facial nerve paresis or paralysis with onset in less than 72 hours without identifiable cause 2

  • Typically self-limited condition
  • May cause facial weakness followed by synkinesis (involuntary facial movements)
  • Affects people 15-45 years old, those with diabetes, compromised immune systems, or during pregnancy

• Hemifacial Spasm: Unilateral, involuntary, irregular clonic or tonic movements of muscles innervated by the seventh cranial nerve 3

  • Most commonly caused by vascular compression of the facial nerve
  • Typically begins in the eyelid and spreads to other facial muscles
  • Usually presents in the third or fourth decade of life
  • Characterized by asymmetric and asynchronous facial contractions 4

• Paroxysmal Kinesigenic Dyskinesia (PKD): Movement-triggered facial twitching 2

  • Triggered by sudden voluntary movements
  • Episodes last less than 1 minute in over 98% of patients
  • May involve face twitching, rigidity of facial muscles, and dysarthria

Serious Causes

• Cerebellopontine Angle Lesions: Tumors, vascular malformations, or inflammation 2
• Brainstem Pathology: Infarction, multiple sclerosis, tumors 2
• Temporal Bone Disorders: Fractures, tumors, inflammation 2
• Parotid Tumors: Can affect the extracranial facial nerve 2

Differential Diagnosis

Several conditions may mimic facial twitching and should be distinguished:

• Blepharospasm: Bilateral involuntary eyelid closure 5
• Facial Tics: Brief, repetitive, stereotyped movements 6
• Facial Myokymia: Fine, continuous, wave-like movements 3
• Tardive Dyskinesia: Medication-induced facial movements 3
• Hemimasticatory Spasm: Affects jaw muscles 6
• Post-Bell's Synkinesis: Abnormal facial movements following Bell's palsy 7

Diagnostic Approach

1. History and Physical Examination:

   • Onset, duration, and triggers of facial twitching
   • Unilateral vs. bilateral involvement
   • Associated symptoms (pain, numbness, weakness)
   • History of trauma, dental procedures, or infections 2

2. Red Flags requiring immediate evaluation: 7, 6

   • Facial numbness or weakness
   • Other neurological symptoms
   • Bilateral involvement (rare in hemifacial spasm)
   • Progressive symptoms
   • Associated hearing loss or tinnitus

3. Imaging:

   • MRI is preferred for evaluating the facial nerve course and potential compression 2
   • High-resolution CT of temporal bone may be complementary to MRI for evaluating osseous integrity 2

Treatment Options

For Bell's Palsy:

• Oral corticosteroids: Strongly recommended within 72 hours of symptom onset 8
  • Significantly improves recovery rates
• Antiviral therapy: May be considered in combination with steroids, but offers minimal additional benefit 8
• Eye protection: Crucial for patients with incomplete eyelid closure 8
  • Artificial tears, ocular ointment, eye patching or taping

For Hemifacial Spasm:

• Botulinum toxin injections: First-line treatment 1, 4, 5, 3
  • Administered into affected facial muscles
  • Effective with few disabling side effects
  • May need to be repeated every 3-4 months

For Paroxysmal Kinesigenic Dyskinesia:

• Anticonvulsant medications: Often effective in controlling symptoms 2

For Secondary Causes:

• Treatment directed at underlying condition (tumor removal, vascular decompression, etc.) 2, 6

Management Considerations

1. Follow-up: Patients with Bell's palsy should be reevaluated if symptoms worsen or don't improve after 3 months 8

2. Botulinum Toxin Administration: 1

   • Proper injection technique is critical
   • Dosing is specific to each botulinum toxin product and not interchangeable
   • Should be administered by clinicians familiar with facial anatomy
   • Potential side effects include ptosis, facial weakness, and rarely, spread of toxin effect

3. Surgical Options:

   • Microvascular decompression may be considered for hemifacial spasm when botulinum toxin is ineffective or contraindicated 3

Prognosis

• Bell's Palsy: 70-94% of patients recover completely, depending on severity 8
• Hemifacial Spasm: Typically chronic but controllable with botulinum toxin 3
• Secondary Causes: Prognosis depends on underlying condition

Facial twitching requires careful evaluation to determine the underlying cause and appropriate treatment. While many cases are benign and treatable, some may indicate serious neurological conditions that require prompt attention.