Background: Benign essential blepharospasm (BEB) is a neurologic disorder characterized by an adult-onset focal dystonia that causes involuntary blinking and eyelid spasms. The pathophysiology of BEB patients remains unclear. This study investigated intrinsic low-frequency fluctuation in BEB patients during resting state functional magnetic resonance imaging (fMRI).
Methods: The study included 9 patients with BEB (mean age, 61.7 years; range, 52-66 years), in whom the average duration of symptoms was 2.7 ± 1.8 years, and another 9 subjects from an age- and sex-matched control group. Resting state fMRI was performed in both the patients with BEB and the normal controls. Voxel-based analysis was used to characterize the alteration of amplitude of low-frequency fluctuation (ALFF) in both patients with BEB and the normal controls.
Results: The whole brain analysis indicated that in comparison with the normal control group, there was a significantly increased ALFF in the left putamen, pallidum, insular lobe, and medial prefrontal cortex and a significantly decreased ALFF in the bilateral somatosensory regions, thalami, cerebellum, and medial and posterior cingulate cortex.
Conclusion: The present study suggests that both an abnormal default mode network and corticostriatopallidothalamic loop may play a role in the pathophysiology of BEB.