Relationship Between Blepharospasm and Headaches
Blepharospasm is not typically associated with headaches as part of its primary presentation, though headaches may occur as a comorbid condition or secondary feature in some patients.
Underlying Mechanisms of Blepharospasm
Blepharospasm is an adult-onset focal dystonia characterized by involuntary contractions of the orbicularis oculi muscles 1. The pathophysiology involves dysfunction in multiple brain regions:
- Basal ganglia, cortex, and cerebellum show functional abnormalities, though it remains unclear whether these changes are cause or consequence of the disorder 2
- The etiology of primary blepharospasm is largely unknown, making therapeutic approaches primarily symptomatic 1
- Various movement patterns can occur, including typical blepharospasm with Charcot's sign, pretarsal blepharospasm, and eyelid flickering 1
Clinical Presentation and Associated Features
Primary blepharospasm typically presents without headache as a defining feature. The condition manifests with:
- Involuntary eyelid closure that may result in functional blindness despite an otherwise normal visual pathway 3
- Onset typically in the fifth and sixth decades of life 3
- Possible association with dystonia in the lower face, jaw, or cervical muscles 1
- Non-motor symptoms may provide clues to understanding the disease better 2
Important Clinical Distinction
Essential blepharospasm, a comorbidity that may be confused with blepharospasm, can be associated with headaches when it occurs as part of Meige syndrome or other dystonic disorders 4. However, this represents a different clinical entity from isolated blepharospasm.
Rare Secondary Causes
While adults presenting with blepharospasm rarely require extensive etiological investigation 1, clinicians should be aware that:
- Structural brain lesions and ophthalmologic conditions can cause secondary blepharospasm 5
- Rare cases have reported blepharospasm as the presenting feature of thyroid and parathyroid neoplasms 5
- Unless clinical clues suggest a symptomatic cause, extensive workup is not warranted 1
Clinical Pitfall to Avoid
Do not confuse blepharospasm with migraine-associated conditions. Migraine-associated vertigo requires migrainous headache as part of diagnostic criteria 4, but this is a completely separate entity from blepharospasm and should not influence the evaluation of isolated blepharospasm.