BACKGROUND: Blepharospasm is a form of focal dystonia that manifests as 
repetitive involuntary closure of the eyes. The pathogenesis of blepharospasm 
and the neuroanatomic substrates involved are not fully understood. Dysfunction 
of the basal ganglia traditionally is presumed to be the main cause of most 
forms of dystonia, but a growing body of evidence suggests that a network of 
additional cortical and subcortical structures may be involved.
METHODS: The medical records of 1114 patients with blepharospasm seen over past 
10 years at Emory University were reviewed to identify potentially contributing 
brain lesions. A systematic review of the published literature was also 
conducted to identify potentially contributing brain lesions.
RESULTS: Among patients with blepharospasm at Emory University, 18 had focal 
lesions on imaging studies available for review. The literature review revealed 
25 articles describing 30 additional cases of blepharospasm associated with 
focal lesions. Among all 48 cases, lesions were found in multiple regions 
including the thalamus (n=12), lower brainstem (n=11), basal ganglia (n=9), 
cerebellum (n=9), midbrain (n=7), and cortex (n=1).
CONCLUSIONS: These data in combination with functional imaging studies of 
primary blepharospasm support a model in which a network of different regions 
plays a role in the pathogenesis of blepharospasm.