Symptomatic dystonias associated with structural brain lesions: Report of 16 cases

Background: Symptomatic (secondary) dystonias associated isolated lesions in the brain provide insight into etiopathogenesis of the idiopathic form of dystonia and are a basis for establishing the possible correlation between the anatomy of a lesion and the type of dystonia according to muscles affected. Methods: In 358 patients with differently distributed dystonias, a group of 16 patients (4.5%) was encountered in whom dystonia was associated with focal brain lesions. Results: Of the 16 patients, 3 patients had generalized, 3 segmental and 3 hemidystonia, while the remaining 6 patients had focal dystonia. The most frequent etiologies were infarction in 7, and tumor in 3 patients. These lesions were usually found in the lenticular and caudate nucleus, thalamus, and in the case of blepharospasm in the upper brainstem. Conclusions: Our results support the suggestion that dystonia is caused by a dysfunction of the basal ganglia.