Hemifacial spasm non-motor and motor-related symptoms and their response to botulinum toxin therapy

Hemifacial spasm (HFS) is a chronic movement disorder which presents as clonic and/or tonic facial muscle contractions frequently accompanied by many other sensory (visual or auditory disturbances, pain), motor (facial weakness, trismus, bruxism, dysarthria) and/or autonomic (lacrimation, salivation) symptoms. The aim of the study was to assess the occurrence of HFS non-motor and motor-related symptoms and their responsiveness to botulinum toxin type A (BTX-A) therapy. 56 HFS patients were included in the open-label design study. Patients were examined three times: before BTX-A injection, and 2 and 12 weeks later. The occurrence of non-motor and motor-related symptoms was assessed by a special questionnaire, and the severity of HFS was rated by the Clinical Global Impression-Severity scale (CGI-S) and depression symptoms by the Beck Depression Inventory (BDI). Over 81% of the patients before BTX-A therapy reported HFS non-motor and motor-related symptoms. Almost 50% of the patients reported more than three symptoms. The most frequent symptoms were: tearing (44.5%), eye irritation (39.3%), facial paraesthesia (26.8%) and hearing of a "clicking" sound (25.0%). 2 weeks after BTX-A injection 75% of the patients did not report any symptoms and 20% reported only one or two. 3 months later the number of symptoms had increased again, with 57% of patients reporting at least one. The number of HFS non-motor and other symptoms did not correlate with the patients' age, disease duration and the presence of neuro-vascular conflict, but were positively correlated with the CGI-S and BDI scores. This study showed that muscle contractions in HFS patients are commonly accompanied by non-motor and other motor-related symptoms and most of them are reduced following BTX-A treatment.