The lesion causing continuous facial myokymia in multiple sclerosis

How to face the hemifacial spasm: challenges and misconceptions

Hemifacial spasm (HFS) is characterised by intermittent, brief or sustained, repetitive contractions of the muscles innervated by one facial nerve. It is one of the most frequent movement disorders affecting the face. However common and allegedly straightforward to diagnose, it might reveal as a challenge for clinicians in various situations. Indeed, it often needs prior exclusion of many other movement disorders affecting the face, with frequent phenomenological overlaps with blepharospasm, post-facial palsy, facial motor tics, etc. The clinical diagnosis shall be supported by modern brain imaging techniques, and sometimes electromyography, as some particular aetiologies may require specific treatment. Primary forms are associated with vascular compression of the ipsilateral seventh cranial nerve, whereas secondary forms can be caused by any injury occurring on the facial nerve course. This article proposes a global and organised approach to the diagnosis, and the ensuing therapeutic options, as many practitioners still use some inefficient medications when they encounter a case of facial spasm.

Movement Disorders in Multiple Sclerosis: An Update

Background:

Multiple sclerosis (MS), a subset of chronic primary inflammatory demyelinating disorders of the central nervous system, is closely associated with various movement disorders. These disorders may be due to MS pathophysiology or be coincidental. This review describes the full spectrum of movement disorders in MS with their possible mechanistic pathways and therapeutic modalities.

Methods:

The authors conducted a narrative literature review by searching for ‘multiple sclerosis’ and the specific movement disorder on PubMed until October 2021. Relevant articles were screened, selected, and included in the review according to groups of movement disorders.

Results:

The most prevalent movement disorders described in MS include restless leg syndrome, tremor, ataxia, parkinsonism, paroxysmal dyskinesias, chorea and ballism, facial myokymia, including hemifacial spasm and spastic paretic hemifacial contracture, tics, and tourettism. The anatomical basis of some of these disorders is poorly understood; however, the link between them and MS is supported by clinical and neuroimaging evidence. Treatment options are disorder-specific and often multidisciplinary, including pharmacological, surgical, and physical therapies.

Discussion:

Movements disorders in MS involve multiple pathophysiological processes and anatomical pathways. Since these disorders can be the presenting symptoms, they may aid in early diagnosis and managing the patient, including monitoring disease progression. Treatment of these disorders is a challenge. Further work needs to be done to understand the prevalence and the pathophysiological mechanisms responsible for movement disorders in MS.

Demystifying the spontaneous phenomena of motor hyperexcitability

Possessing a discrete functional repertoire, the anterior horn cell can be in one of two electrophysiological states: on or off. Usually under tight regulatory control by the central nervous system, a hierarchical network of these specialist neurons ensures muscular strength is coordinated, gradated and adaptable. However, spontaneous activation of these cells and their axons can result in abnormal muscular twitching. The muscular twitch is the common building block of several distinct clinical patterns, namely fasciculation, myokymia and neuromyotonia. When attempting to distinguish these entities electromyographically, their unique temporal and morphological profiles must be appreciated. Detection and quantification of burst duration, firing frequency, multiplet patterns and amplitude are informative. A common feature is their persistence during sleep. In this review, we explain the accepted terminology used to describe the spontaneous phenomena of motor hyperexcitability, highlighting potential pitfalls amidst a bemusing and complex collection of overlapping terms. We outline the relevance of these findings within the context of disease, principally amyotrophic lateral sclerosis, Isaacs syndrome and Morvan syndrome. In addition, we highlight the use of high-density surface electromyography, suggesting that more widespread use of this non-invasive technique is likely to provide an enhanced understanding of these motor hyperexcitability syndromes.

Continuous facial myokymia in multiple sclerosis

Facial myokymia is a clinical sign that can occur as a manifestation of demyelinating lesions. As seen in our patient with multiple sclerosis, acute-onset continuous facial myokymia can be indicative of an active lesion and can have localizing value.

Paroxysmal Symptoms in Multiple Sclerosis-A Review of the Literature

Paroxysmal symptoms are well-recognized manifestations of multiple sclerosis (MS). These are characterized by multiple, brief, sudden onset, and stereotyped episodes. They manifest as motor, sensory, visual, brainstem, and autonomic symptoms. When occurring in the setting of an established MS, the diagnosis is relatively straightforward. Conversely, the diagnosis is significantly more challenging when they occur as the initial manifestation of MS. The aim of this review is to summarize the various forms of paroxysmal symptoms reported in MS, with emphasis on the clinical features, radiological findings and treatment options.

Multiple Sclerosis Presenting with Facial Twitching (Myokymia and Hemifacial Spasms)

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system. The etiology is insufficiently understood. Autoimmune, genetic, viral, and environmental factors have been hypothesized. MS is twice as common in women as in men between the ages of 20 and 50 years. There is no known cure for MS. Current medical treatment helps to prevent new attacks and improve function after an attack. MS is diagnosed by physical examination, diagnostic imaging, and examination of cerebral spinal fluid. The most common physical signs and symptoms of MS include constitutional symptoms, muscle weakness, motor and autonomic spinal cord symptoms, paresthesias, and vision changes. Here we present a case of MS diagnosed in a 33-year-old male with facial myokymia of left eyelid, which progressed to left hemifacial spasm. This is an unusual presentation for multiple sclerosis. An awareness of this presentation not only may lead to an earlier diagnosis in some patients but can be a sign of relapse in patients with established multiple sclerosis.

Botulinum Toxin Treatment in Multiple Sclerosis-a Review

Purpose of review The purpose of this review is to provide updated information on the role of botulinum neurotoxin (BoNT) therapy in multiple sclerosis (MS). This review aims to answer which symptoms of multiple sclerosis may be amenable to BoNT therapy. Recent findings We searched the literature on the efficacy of BoNTs for treatment of MS symptoms up to April 1st 2017 via the Yale University Library's search engine including but not limited to Pub Med and Ovis SP. The level of efficacy was defined according to the assessment's criteria set forth by the Subcommittee on Guideline Development of the American Academy of Neurology. Significant efficacy was found for two indications based on the available blinded studies (class I and II) and has been suggested for several others through open-label clinical trials. Summary There is level A evidence (effective- two or more class I) that injection of BoNT-A into the bladder's detrusor muscle improves MS-related neurogenic detrusor overactivity (NDO) and MS-related overactive (OA) bladder. There is level B evidence (probably effective- two class II studies) for utility of intramuscular BoNT-A injections for spasticity of multiple sclerosis. Emerging data based on retrospective class IV studies demonstrates that intramuscular injection of BoNTs may help other symptoms of MS such as focal tonic spasms, focal myokymia, spastic dysphagia, and double vision in internuclear ophthalmoplegia. There is no data on MS-related trigeminal neuralgia and sialorrhea, two conditions which have been shown to respond to BoNT therapy in non-MS population.

Misleading bilateral blink reflex loss in a severe tetanus case

Tetanus is rare and often forgotten in the diagnostic workup. The diagnosis is mainly based on typical clinical symptoms, because of missing sensitive paraclinical test. As described in our case, a missing bilateral blink reflex may occur in severe tetanus, which should not lead to the rejection of the diagnosis.

Continuous hemifacial myokymia as the revealing symptom of demyelinating disease of the CNS

Facial myokymia (FM) is an uncommon involuntary movement, disorder of the musculature supplied by the facial nerve and, characterized by spontaneous undulating, vermicular movements beneath the, skin. It has rarely been described as a form of presentation of multiple, sclerosis. We describe a 31-year-old man presenting with continuous, unilateral facial myokymia as the revealing symptom of a demyelinating, disorder of central nervous system. Brain magnetic resonance imaging, showed an ipsilateral pontine T2/FLAIR hyperintensity close to the, postgenu course of facial nerve, suggestive of a segmental demyelination, of facial nerve causing facial nuclear hyperactivity and resulting in FM., Facial myokymia must raise the possibility of MS in adults under the age, of 40.

Facial synkinesis as a first symptom of multiple sclerosis

A 39-year-old woman was admitted to hospital because of a sensory hemisyndrome caused by a contrast-enhancing demyelinating lesion of the cervical cord. MRI, CSF examination and subsequent clinical and neuroradiological follow-up led to the diagnosis of multiple sclerosis. The patient had noticed an involuntary contraction of a small muscle fascicle on the right side of the chin for a year. Electromyographic and video recordings confirmed the synkinesis between the orbicularis oculi and lower facial muscles, a finding distinct from the myokymic discharges reported in multiple sclerosis and more similar to the synkinesis associated with hemifacial spasm.

Abnormal control of orbicularis oculi reflex excitability in multiple sclerosis

Brain lesions in patients with multiple sclerosis may lead to abnormal excitability of brainstem reflex circuits because of impairment of descending control pathways. We hypothesized that such abnormality should show in the analysis of blink reflex responses in the form of asymmetries in response size. The study was done in 20 patients with relapsing-remitting multiple sclerosis and 12 matched healthy subjects. We identified first patients with latency abnormalities (AbLat). Then, we analyzed response size by calculating the R2c/R2 ratio to stimulation of either side and the mean area of the R2 responses obtained in the same side. Patients with significantly larger response size with respect to healthy subjects in at least one side were considered to have abnormal response excitability (AbEx). We also examined the blink reflex excitability recovery (BRER) and prepulse inhibition (BRIP) of either side in search for additional indices of asymmetry in response excitability. Neurophysiological data were correlated with MRI-determined brain lesion-load and volume. Eight patients were identified as AbLat (median Expanded Disability Status Scale–EDSS = 2.75) and 7 of them had ponto-medullary lesions. Nine patients were identified as AbEx (EDSS = 1.5) and only 2 of them, who also were AbLat, had ponto-medullary lesions. In AbEx patients, the abnormalities in response size were confined to one side, with a similar tendency in most variables (significantly asymmetric R1 amplitude, BRER index and BRIP percentage). AbEx patients had asymmetric distribution of hemispheral lesions, in contrast with the symmetric pattern observed in AbLat. The brainstem lesion load was significantly lower in AbEx than in AbLat patients (p = 0.04). Asymmetric abnormalities in blink reflex response excitability in patients with multiple sclerosis are associated with lesser disability and lower tissue loss than abnormalities in response latency. Testing response excitability could provide a reliable neurophysiological index of dysfunction in early stages of multiple sclerosis.

Unilateral facial myokymia in a dog with an intracranial meningioma

A 23-month-old castrated male Cavalier King Charles spaniel was evaluated because of a 6-month history of unusual rippling/undulating movements of the right facial muscles that were continuous and persisted during sleep. Neurological examination revealed narrowing of the right palpebral fissure and unilateral right-sided facial myokymia that was characterised by myokymic, and to a lesser degree, neuromyotonic discharges on concentric needle electromyographic examination. After persisting unchanged for almost 2.5 years from its onset, the facial myokymia gradually disappeared over a 6-month period concomitant with the emergence of a persistent ipsilateral facial paralysis and head tilt. At 5 years and 9 months after the first examination, signs of ipsilateral lacrimal, pharyngeal and laryngeal dysfunction became evident and the dog was euthanased. Postmortem examination identified a malignant (WHO grade III) meningioma in the right cerebellopontomedullary angle that compressed the ventrolateral cranial medulla, effaced the jugular foramen and internal acoustic meatus and extended into the facial canal of the petrous temporal bone. Novel findings were the unique observation of isolated unilateral facial myokymia preceding diagnosis of a meningioma affecting facial nerve function within the caudal cranial fossa and the remarkably long duration of neurological signs (75 months) attributable to the neoplasm.

Tremor on smiling

Facial tremor occurring on smiling is a rare phenomenon and has been described (to the best of our knowledge) in the literature only once. We describe two patients who presented with a bilateral facial tremor that occurred only on smiling and other activation of therisorii muscles and had a high frequency of 9 Hz. One patient additionally suffered from young-onset Parkinson's disease, whereas the other had no further neurological symptoms or signs apart from this tremor. Anti-parkinsonian medication was unhelpful for the facial tremor in the patient with Parkinson's disease. Tremor on smiling may be a discrete entity or may be associated in some cases of Parkinson's disease.

Spastic paretic hemifacial contracture in multiple sclerosis: a neglected clinical and EMG entity

Background

Spastic paretic hemifacial contracture (SPHC) is an uncommon condition, originally described as a sign of brainstem neoplasia, characterized by sustained unilateral contraction of the facial muscles associated with mild ipsilateral facial paresis. SPHC has only rarely been reported in the context of multiple sclerosis (MS). To further study and assess the frequency of SPHC in patients with MS.

Methods

We screened clinically 500 consecutive patients with MS for the presence of SPHC and further studied electrophysiologically any cases identified.

Results

We identified two patients who developed the condition during the course of an MS relapse. The estimated frequency of the condition was 0.4%. Both patients had relapsing–remitting MS. SPHC was characterized on Electromyography (EMG) by continuous resting activity of irregularly firing motor unit potentials, associated with impaired recruitment of motor units on voluntary contraction. Myokymic discharges were not present. Blink reflex studies were partly consistent with midpontine lesions in the vicinity of the facial nucleus ipsilateral to SPHC. MRI showed lesions in the ipsilateral dorsolateral midpontine tegmentum.

Conclusions

SPHC constitutes a rare but distinct clinical and EMG entity in patients with MS.

Chronic Myokymia Limited to the Eyelid Is a Benign Condition

BACKGROUND

Eyelid myokymia, unlike myokymia of the other facial muscles, is assumed to be a benign, self-limited disorder. However, no systematic follow-up study has been performed on patients with chronic, isolated eyelid myokymia to verify its benign nature.

METHODS

Retrospective single-institution chart review of 15 patients examined between 1983 and 2002 with a diagnosis of isolated eyelid myokymia who have had at least 12 months of follow-up.

RESULTS

In all patients, symptoms began as unilateral, weekly or biweekly, intermittent eyelid spasms, and progressed to daily spasms over several months. The mean duration of symptoms at first examination was 91 months (range 2.5 months to 20 years). In no patient was the myokymia the first manifestation of a neurologic disease, although one patient progressed to ipsilateral hemifacial spasm. Thirteen patients (86.7%) underwent neuroimaging that gave negative results. The myokymia resolved spontaneously in four patients. Of the remaining 11 patients, eight were treated with botulinum toxin injection at regular intervals, with most reporting an improvement in symptoms.

CONCLUSION

Chronic isolated eyelid myokymia is a benign condition. It tends not to progress to other facial movement disorders or to be associated with other neurologic disease. It responds well to treatment with botulinum toxin.

Facial myokymia in brain death

BACKGROUND

Brain death (BD) is the irreversible loss of all functions of the brain and brainstem. Spontaneous and reflex movements of the limbs have been described in this condition. However, facial myokymia (FM) in BD has not been previously reported. The origin of that motor phenomenon in alive patients is still uncertain, since supranuclear, nuclear and peripheral mechanisms have been proposed.

OBJECTIVE

We describe the presence of FM in a patient who fulfilled the criteria for BD. A 40-year-old-man had right-sided weakness and impaired consciousness. After 14 h admission, he fulfilled the criteria for BD. A CT scan of the head showed a large putaminal hemorrhage. The EEG was isoelectric. At that time, fine spontaneous twitches of the left cheek were noticed. They consisted of repetitive and rhythmic movements in groups of 3-5 lasting for < 5 s. These movements appeared every 2-10 min during 6 h.

DISCUSSION

Spinal reflexes have been described in BD. The presence of any movements other than the recognized reflexes may question this diagnosis and limit organ procurement for transplantation. The recognition of FM as an accepted movement in BD patients has practical and legal implications.

The pathophysiology of multiple sclerosis: the mechanisms underlying the production of symptoms and the natural history of the disease

The pathophysiology of multiple sclerosis is reviewed, with emphasis on the axonal conduction properties underlying the production of symptoms, and the course of the disease. The major cause of the negative symptoms during relapses (e.g. paralysis, blindness and numbness) is conduction block, caused largely by demyelination and inflammation, and possibly by defects in synaptic transmission and putative circulating blocking factors. Recovery from symptoms during remissions is due mainly to the restoration of axonal function, either by remyelination, the resolution of inflammation, or the restoration of conduction to axons which persist in the demyelinated state. Conduction in the latter axons shows a number of deficits, particularly with regard to the conduction of trains of impulses and these contribute to weakness and sensory problems. The mechanisms underlying the sensitivity of symptoms to changes in body temperature (Uhthoff's phenomenon) are discussed. The origin of 'positive' symptoms, such as tingling sensations, are described, including the generation of ectopic trains and bursts of impulses, ephaptic interactions between axons and/or neurons, the triggering of additional, spurious impulses by the transmission of normal impulses, the mechanosensitivity of axons underlying movement-induced sensations (e.g. Lhermitte's phenomenon) and pain. The clinical course of the disease is discussed, together with its relationship to the evolution of lesions as revealed by magnetic resonance imaging and spectroscopy. The earliest detectable event in the development of most new lesions is a breakdown of the blood-brain barrier in association with inflammation. Inflammation resolves after approximately one month, at which time there is an improvement in the symptoms. Demyelination occurs during the inflammatory phase of the lesion. An important mechanism determining persistent neurological deficit is axonal degeneration, although persistent conduction block arising from the failure of repair mechanisms probably also contributes.

Bilateral hemifacial spasm: a report of five cases and a literature review

We describe five patients with bilateral hemifacial spasm evaluated in a Movement Disorders Clinic to illustrate the clinical characteristics and to draw attention to the differential diagnosis of this condition. All patients had unilateral onset followed by bilateral, asymmetric, and asynchronous facial contractions. The mean age of the patients (4 women and 1 man) was 70.6 years (range, 54-81 yrs), and the mean duration of symptoms was 17 years (range, 2-30 yrs). The facial twitching started in the left eyelid in all cases and the opposite side of the face began to twitch on the average 8.4 years (range, 0.2-15 yrs) later. Imaging studies revealed tortuous vertebrobasilar arteries in three patients. Four patients were successfully treated with botulinum toxin injections. Bilateral hemifacial spasm is a rare, peripherally induced disorder that must be differentiated from tics, dystonia including blepharospasm and other cranial dystonia, and other facial dyskinesias. Botulinum toxin injection appears to be the treatment of choice.

Hemifacial spasm: clinical findings and treatment

Hemifacial spasm (HFS) is a peripherally induced movement disorder characterized by involuntary, unilateral, intermittent, irregular, tonic or clonic contractions of muscles innervated by the ipsilateral facial nerve. We reviewed the clinical features and response to different treatments in 158 patients (61% women) with HFS evaluated at our Movement Disorders Clinic. The mean age at onset was 48.5+/-14.1 years (range: 15-87) and the mean duration of symptoms was 11.4+/-8.5 (range: 0.5-53) years. The left side was affected in 56% instances; 5 patients had bilateral HFS. The lower lid was the most common site of the initial involvement followed by cheek and perioral region. Involuntary eye closure which interfered with vision and social embarrassment were the most common complaints. HFS was associated with trigeminal neuralgia in 5.1% of the cases and 5.7% had prior history of Bell's palsy. Although vascular abnormalities, facial nerve injury, and intracranial tumor were responsible for symptoms in some patients, most patients had no apparent etiology. Botulinum toxin type A (BTX-A) injections, used in 110 patients, provided marked to moderate improvement in 95% of patients. Seven of the 25 (28%) patients who had microvascular decompression reported permanent complications and the HFS recurred in 5 (20%). Although occasionally troublesome, HFS is generally a benign disorder that can be treated effectively with either BTX-A or microvascular decompression.

Serial Gadolinium-Enhanced Magnetic Resonance Imaging and Assessment of Facial Nerve Function in Bell's Palsy

Eleven patients with mild or moderate acute idiopathic peripheral facial palsy, so-called Bell's palsy, were serially examined by gadolinium-DTPA-enhanced MRI on mean days 11, 40, and 97 (third examination, n = 10) after the onset of palsy. Results of the clinical and neurophysiologic assessment of facial nerve function were compared with the gadolinium-enhanced MRI findings. Eight of the 11 patients demonstrated contrast enhancement of the facial nerve at the initial examination, but in 7 of them, the enhancement had disappeared by the time of the serial follow-up gadolinium-enhanced MRI scans. The disappearance of facial nerve enhancement was found to be related to clinical and neurophysiologic improvements in facial nerve function during recovery from Bell's palsy. The three patients whose scans were negative at the initial gadolinium-enhanced MRI examination had the same clinical severity of palsy, but initially they had milder neurophysiologic involvement than those who demonstrated enhancement; these three patients did not exhibit enhancement at serial follow-up scans. These findings indicate that the presence of enhancement at the initial MRI scan is not necessarily indicative of a poor prognosis for recovery.

Experimental facial myokymia in cat

INTRODUCTION

The objective of this study was to describe facial myokymia in experimental animals accompanying kainic acid affects on facial motor neurons.

MATERIAL & METHODS

Anesthetized cats were injected with kainic acid into the pons adjacent to the facial nucleus. Facial movements appeared shortly after the injections and facial electromyographic potentials were recorded. Cats were killed up to 4 weeks later, the brainstems were processed histologically, and the number of neurons in the facial nucleus counted.

RESULTS

Cats receiving injection of kainic acid adjacent to facial nucleus all developed spontaneous writhing movements of the face ipsilateral to the injection site, clinically resembling facial myokymia in humans. Transient facial paresis, lasting several weeks, appeared in some of the cats. Facial myokymia occurred independent of histological evidence of neuronal loss in facial nucleus, whereas facial paresis occurred in all but one of the animals with significant neuronal loss in the facial nucleus. Placing a needle into the superior olive without injecting kainic acid or injections of kainic acid into cochlear nucleus was not accompanied by facial myokymia or subsequent facial paresis.

CONCLUSION

Facial movements in cats similar to myokymia in humans accompanies kainic acid injections adjacent to the nucleus of the facial nerve.