What is the approach for examining and treating blepharospasm?

Examination and Treatment Approach for Blepharospasm

Clinical Examination

Perform a comprehensive eye examination with slit-lamp biomicroscopy to identify the characteristic involuntary contractions of the orbicularis oculi muscles and rule out secondary causes. 1

History Taking

• Duration and pattern of symptoms: Ask specifically about involuntary eyelid closure, increased blinking frequency, and whether symptoms worsen in bright light or with stress 1, 2
• Associated features: Screen for oromandibular dystonia, cervical dystonia, or other focal dystonias that may indicate Meige syndrome 2
• Family history: Document any family history of dystonia or movement disorders 3
• Neurological symptoms: Rule out associated neurological disorders including Parkinson's disease, as these predict poorer treatment outcomes 3
• Medication history: Review current medications, particularly those that may cause secondary blepharospasm 1

Physical Examination Components

External examination should assess:

• Eyelid position and function: Evaluate for ptosis, lagophthalmos, and abnormal eyelid closure patterns 1
• Blink response: Observe for increased frequency, flickering movements, and pretarsal spasm 2
• Charcot's sign: Look for elevation of the eyebrows during forced eyelid closure 2
• Apraxia of eyelid opening: Test ability to voluntarily open eyes after forced closure 2, 4

Slit-lamp biomicroscopy must include:

• Corneal examination: Assess for exposure keratopathy, epithelial defects, or ulceration that may result from reduced blinking 5
• Tear film evaluation: Check for signs of dry eye disease 1
• Meibomian gland assessment: Evaluate for concurrent blepharitis or meibomian gland dysfunction 1

Diagnostic Considerations

• Rule out secondary causes: Unless clinical clues suggest symptomatic blepharospasm, extensive neurological investigation is not required in adults with typical presentation 2
• Assess severity: Use standardized scales such as the Jankovic Rating Scale and blepharospasm disability index to quantify baseline severity 4

Treatment Algorithm

First-Line Treatment: Botulinum Toxin Type A

Botulinum toxin type A injections into the orbicularis oculi muscle are the treatment of choice for blepharospasm. 5, 2, 6

Injection technique:

• Target the orbicularis oculi muscle with multiple injection sites around the eyelids 7
• Expect rapid relief from spasms within days to one week 5, 7
• Beneficial effects typically last 8-14 weeks, requiring repeat injections 7, 3
• 71-89% of patients achieve normal or near-normal vision restoration 3

Expected outcomes and monitoring:

• Older patients and those without oromandibular dystonia respond better 3
• Patients with associated neurological disorders have poorer outcomes 3
• Common side effects include temporary partial ptosis, which is generally well-tolerated 3, 5

Critical safety monitoring:

• Corneal protection: Reduced blinking from botulinum toxin can lead to corneal exposure, persistent epithelial defects, and ulceration 5
• Employ vigorous treatment of any corneal defect with protective drops, ointment, therapeutic soft contact lenses, or eye patching 5
• Monitor for dry eye symptoms (irritation, photophobia, visual changes) and refer to ophthalmologist if persistent 5

Second-Line Treatment: Adjunctive Therapies

If botulinum toxin alone provides insufficient relief:

• Photochromatic lenses: Consider for patients with significant photophobia 6
• Oral medications: Trial of medications may be considered, though success rates are low (only 1 in 36 patients responded in one series) 7
• Pimozide showed benefit in isolated cases after other medications failed 7

Third-Line Treatment: Surgical Intervention

Surgery is reserved for patients who fail or become resistant to botulinum toxin therapy. 6, 4

Surgical options include:

• Myectomy: Eyebrow-eyelid muscle stripping surgery shows considerable improvement 7
• Frontalis suspension or direct brow lift: With or without upper lid blepharoplasty for severe cases 4
• Expect side effects including frontal anesthesia, exposure keratitis, lagophthalmus, scarring, and eyelid malposition 7
• Residual spasm may persist in approximately 50% of surgical cases 7

Special Populations

For blepharospasm secondary to deep brain stimulation:

• Use multimodality approach combining botulinum toxin with potential surgical intervention 4
• Adjust STN-DBS stimulation settings as needed 4
• Surgery may be required if toxin treatment becomes ineffective 4

Common Pitfalls to Avoid

• Do not delay corneal protection measures after botulinum toxin injection, as reduced blinking can rapidly lead to sight-threatening corneal complications 5
• Do not assume all eyelid spasm is primary blepharospasm: Always rule out secondary causes including medications, neurological disorders, and ocular surface disease 1, 2
• Do not expect increasing duration of benefit with repeated botulinum toxin injections—the average 8-9 week duration remains stable over time 3