Blepharoclonus in multiple sclerosis.

Abstract

Keane described 2 patients with gaze-evoked blepharoclonus (BLC), a form of reflex BLC, and multiple sclerosis (MS). A search for common areas of demyelination and focal axonal atrophy (T1 black holes) of the central nervous system (CNS) in 11 patients with MS exhibiting eyelid closure BLC was conducted employing magnetic resonance imaging (MRI). Finding lesions in common CNS locations on these patients can help to elucidate the pathogenesis of this restricted movement disorder. Eleven adult patients with relapsing-remitting, primary or secondary progressive MS were studied. MRI views were completed employing a 1.5-tesla scanner. Contrast Axial T1 imaging was obtained in 9 patients. TL blackholes were not identified. Ten patients had multiple, scattered periventricular (PV) areas of demyelination. Four patients exhibited brainstem lesions of diverse but inconsistent locations including midbrain, cerebellar peduncle, pons and medulla. In 2 of the patients the brainstem lesions were transient but BLC persisted after the lesions regressed. No common areas of CNS demyelination or focal axonal atrophy were identified on these patients with MS and BLC. The pathogenesis and clinical significance of BLC in MS remains to be elucidated.