Clinical features of facial myokymia and its treatment with botulinum toxin A / 中风与神经疾病杂志

ABSTRACT

@#Objective To investigate the clinical features of facial myokymia (FM),assess the therapeutic effect of botulinum toxin A for this condition,and offer clinical guidance for the treatment of this rare disease. Methods A retrospective analysis was performed on the clinical data of 17 patients who visited the Dyskinesia Outpatient Clinic of the Department of Neurology in Peking Union Medical College Hospital and were diagnosed with FM or facial peristalsis from March 2018 to March 2023,and the patients were followed up for the therapeutic effect of botulinum toxin A. Results Among the 17 patients with FM,12 were female and 5 were male;the mean age of onset was (31.4±9.3) years,and the duration of disease ranged from 1.5 months to 22 years. Unilateral onset was seen in all the cases;the onset in 3 cases was associated with trauma or extreme fatigue,while the cause was unclear in the remaining cases. The initial symptoms affected the lower eyelid,temporal muscle,and masseter muscle;symptoms progressed to the muscles on the same side of the face in 6 cases and involved the lower eyelid on the opposite side in 1 case;6 cases had concomitant pain;9 cases experienced functional impairment;12 cases had worsening symptoms due to coldness,tension,excitement,or strong light stimulation;1 case had head MRI results which revealed abnormal signals in the right insula,possibly due to abnormal congenital development (gray matter heterotopia);1 case had MRI results which revealed multiple intracranial ischemic foci. Seven cases showed improved symptoms after the use of carbamazepine,oxcarbazepine,phenytoin sodium,baclofen,and nicergoline during the course of disease;4 cases showed no response;6 cases did not receive any medication. Ten cases received treatment with BTX-A injection,with a mean onset of action of (5.0±2.7) days,a mean time to best effect of (8.5±4.9) days,a mean improvement rate of (78.5±15.8)%,and a mean maintenance time of (7.1±2.9) months. Following BTX-A injection,all patients experienced alleviation of anxiety and pain. Five cases who received regular BTX-A injections had a mean maintenance time of (6.3±3.4) months and a mean improvement rate of (85±13.7)%. Conclusion FM is a rare disease,lacking effective treatment consensus. Botulinum toxin A injection is a safe and effective treatment and is considered a first-line treatment for various types of focal dystonia. Based on limited case reports in the literature and our clinical research experience,botulinum toxin A injection can be recommended for the symptomatic treatment of FM.