Hemifacial myokymia is a rare clinical sign characterised by involuntary undulating waves of unilateral facial muscle contraction. Additionally, there is often tonic contraction of the muscles of the affected side. It is highly associated with ipsilateral pontine lesions particularly multiple sclerosis (MS) plaques and tumours. This has only infrequently been reported as the presenting feature of MS.Case report
Here we present a case of a 46 year old woman presenting with 8 days of right sided continuous facial myokymia (CFM) and right facial contraction. She had no previous symptoms suggestive of neurological disease except episodes of right foot paraesthesia/numbness associated with lower back pain. MRI FLAIR sequences did not demonstrate a brainstem lesion, however multiple hyperintense white matter lesions were detected with an appearance compatible with MS diagnosis based on the 2016 MAGNIMS revision of the McDonald criteria.Discussion
The association between MS and CFM is well established. In a previous study the vast majority of patients had an MRI lesion located in the ipsilateral postgenu portion of the facial nerve. Our case is unusual firstly because no pontine lesion was demonstrated and secondly because CFM has only very rarely been reported as the presenting feature of MS.