Symptomatic dystonias associated with structural brain lesions: report of 16 cases

Isolated Cervical Dystonia: Diagnosis and Classification

This document presents a consensus on the diagnosis and classification of isolated cervical dystonia (iCD) with a review of proposed terminology. The International Parkinson and Movement Disorder Society Dystonia Study Group convened a panel of experts to review the main clinical and diagnostic issues related to iCD and to arrive at a consensus on diagnostic criteria and classification. These criteria are intended for use in clinical research, but also may be used to guide clinical practice. The benchmark is expert clinical observation and evaluation. The criteria aim to systematize the use of terminology as well as the diagnostic process, to make it reproducible across centers and applicable by expert and non-expert clinicians. Although motor abnormalities remain central, increasing recognition has been given to nonmotor manifestations, which are incorporated into the current criteria. Three iCD presentations are described in some detail: idiopathic (focal or segmental) iCD, genetic iCD, and acquired iCD. The relationship between iCD and isolated head tremor is also reviewed. Recognition of idiopathic iCD has two levels of certainty, definite or probable, supported by specific diagnostic criteria. Although a probable diagnosis is appropriate for clinical practice, a higher diagnostic level may be required for specific research studies. The consensus retains elements proven valuable in previous criteria and omits aspects that are no longer justified, thereby encapsulating diagnosis according to current knowledge. As understanding of iCD expands, these criteria will need continuous revision to accommodate new advances. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Possible Post-Traumatic Focal Dystonia Associated with Tau Pathology Localized to Putamen-Globus Pallidus

Background

Dystonia is often associated with damage to basal ganglia (BG), but neuropathological assessments of these cases are infrequent.

Methods

A brain was assessed with possible post-traumatic focal dystonia that appeared after an accident occurred during childhood.

Results

Tau pathology was found within putamen and globus pallidus of the right hemisphere, and chronic traumatic encephalopathy (CTE) was observed in the cortex of the left hemisphere. No diffuse axonal injury (DAI), β-amyloid, ubiquitin, p62, or pTDP43 pathology was found.

Conclusions

Post-traumatic dystonia could be associated with post-traumatic tau pathology formation. However, more cases are necessary to establish causality. The tau lesions found in the BG of this patient did not fit within CTE criteria. We hypothesize that due to the anatomo-histological characteristics of the BG, tau pathology associated with brain traumas produce histopathological patterns different from sulcal-tau pathology, which is the only tau pathology distribution currently accepted as pathognomonic of CTE.

Comparison of dystonia between Parkinson's disease and atypical parkinsonism: The clinical usefulness of dystonia distribution and characteristics in the differential diagnosis of parkinsonism

OBJECTIVE

Dystonia is occasionally found in patients with Parkinson's disease (PD) and atypical parkinsonisms. However, systematic comparative analysis of the association between dystonia and parkinsonism have seldom been reported. The goals of this study are to compare the clinical characteristics and distributions of dystonia between PD, multiple system atrophy (MSA), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD).

METHODS

We prospectively enrolled 176 patients who presented with dystonia and parkinsonism out of 1278 patients with parkinsonism. We analyzed the clinical features of dystonia and parkinsonism.

RESULTS

The frequencies of dystonia were 11.0% in PD, 20.9% in MSA, 40.7% in PSP and 66.7% in CBD. Dystonia symptoms were most frequent in CBD and relatively more frequent in PSP and MSA (p<0.001). Moreover, multiple types of dystonia occurred most frequently in MSA (p=0.034). According to the distribution of dystonia, cranio-facial dystonia (CFD) and cervical dystonia (CD) were more frequently observed in atypical parkinsonism (p=0.001). In contrast, limb dystonia (LD) was more frequently observed in both PD and CBD, and truncal dystonia (TD) was more frequently detected in PD (p<0.001). Levodopa medication related dystonia was markedly more frequent in PD than in atypical parkinsonism (p=0.030).

CONCLUSIONS

In this long-term, observational, prospective study, we concluded that levodopa medication related LD and TD were more frequently observed in PD than in atypical parkinsonism. Conversely, levodopa medication non-related CFD and CD were more frequently observed in atypical parkinsonism, and coexisting of some types of multiple dystonia may be unique features of atypical parkinsonism. TD or multiple types of LD, might be representative of PD rather than atypical parkinsonism.

Contribution of TMS and rTMS in the Understanding of the Pathophysiology and in the Treatment of Dystonia

Dystonias represent a heterogeneous group of movement disorders responsible for sustained muscle contraction, abnormal postures, and muscle twists. It can affect focal or segmental body parts or be generalized. Primary dystonia is the most common form of dystonia but it can also be secondary to metabolic or structural dysfunction, the consequence of a drug's side-effect or of genetic origin. The pathophysiology is still not elucidated. Based on lesion studies, dystonia has been regarded as a pure motor dysfunction of the basal ganglia loop. However, basal ganglia lesions do not consistently produce dystonia and lesions outside basal ganglia can lead to dystonia; mild sensory abnormalities have been reported in the dystonic limb and imaging studies have shown involvement of multiple other brain regions including the cerebellum and the cerebral motor, premotor and sensorimotor cortices. Transcranial magnetic stimulation (TMS) is a non-invasive technique of brain stimulation with a magnetic field applied over the cortex allowing investigation of cortical excitability. Hyperexcitability of contralateral motor cortex has been suggested to be the trigger of focal dystonia. High or low frequency repetitive TMS (rTMS) can induce excitatory or inhibitory lasting effects beyond the time of stimulation and protocols have been developed having either a positive or a negative effect on cortical excitability and associated with prevention of cell death, γ-aminobutyric acid (GABA) interneurons mediated inhibition and brain-derived neurotrophic factor modulation. rTMS studies as a therapeutic strategy of dystonia have been conducted to modulate the cerebral areas involved in the disease. Especially, when applied on the contralateral (pre)-motor cortex or supplementary motor area of brains of small cohorts of dystonic patients, rTMS has shown a beneficial transient clinical effect in association with restrained motor cortex excitability. TMS is currently a valuable tool to improve our understanding of the pathophysiology of dystonia but large controlled studies using sham stimulation are still necessary to delineate the place of rTMS in the therapeutic strategy of dystonia. In this review, we will focus successively on the use of TMS as a tool to better understand pathophysiology, and the use of rTMS as a therapeutic strategy.

The anatomical basis of upper limb dystonia: lesson from secondary cases

Upper limb dystonia is a focal dystonia that may affect muscles in the arm, forearm and hand. The neuroanatomical substrates involved in upper limb dystonia are not fully understood. Traditionally, dysfunction of the basal ganglia is presumed to be the main cause of dystonia but a growing body of evidence suggests that a network of additional cortical and subcortical structures may be involved. To identify the brain regions that are affected in secondary upper limb dystonia may help to better understand the neuroanatomical basis of the condition. We considered only patients with focal upper limb dystonia associated with a single localized brain lesion. To identify these patients, we conducted a systematic review of the published literature as well as the medical records of 350 patients with adult-onset dystonia seen over past 15 years at our movement disorder clinic. The literature review revealed 36 articles describing 72 cases of focal upper limb dystonia associated with focal lesions. Among patients at our clinic, four had focal lesions on imaging studies. Lesions were found in multiple regions including thalamus (n = 39), basal ganglia (n = 17), cortex (n = 4), brainstem (n = 4), cerebellum (n = 1), and cervical spine (n = 7). Dystonic tremor was not associated with any particular site of lesion, whereas there was a trend for an inverse association between task specificity and thalamic involvement. These data in combination with functional imaging studies of idiopathic upper limb dystonia support a model in which a network of different regions plays a role in pathogenesis.

Animal models for dystonia

Symptomatic animal models have clinical features consistent with human disorders and are often used to identify the anatomical and physiological processes involved in the expression of symptoms and to experimentally demonstrate causality where it would be infeasible in the patient population. Rodent and primate models of dystonia have identified basal ganglia abnormalities, including alterations in striatal GABAergic (ie, transmitting or secreting γ-aminobutyric acid) and dopaminergic transmission. Symptomatic animal models have also established the critical role of the cerebellum in dystonia, particularly abnormal glutamate signaling and aberrant Purkinje cell activity. Further, experiments suggest that the basal ganglia and cerebellum are nodes in an integrated network that is dysfunctional in dystonia. The knowledge gained from experiments in symptomatic animal models may serve as the foundation for the development of novel therapeutic interventions to treat dystonia. © 2013 Movement Disorder Society.

Nonprimary dystonias

Dystonias can be classified as primary or secondary, as dystonia-plus syndromes, and as heredodegenerative dystonias. Their prevalence is difficult to determine. In our experience 80-90% of all dystonias are primary. About 20-30% of those have a genetic background; 10-20% are secondary, with tardive dystonia and dystonia in cerebral palsy being the most common forms. If dystonia in spastic conditions is accepted as secondary dystonia, this is the most common form of all dystonia. In primary dystonias, the dystonic movements are the only symptoms. In secondary dystonias, dystonic movements result from exogenous processes directly or indirectly affecting brain parenchyma. They may be caused by focal and diffuse brain damage, drugs, chemical agents, physical interactions with the central nervous system, and indirect central nervous system effects. Dystonia-plus syndromes describe brain parenchyma processes producing predominantly dystonia together with other movement disorders. They include dopa-responsive dystonia and myoclonus-dystonia. Heredodegenerative dystonias are dystonic movements occurring in the context of other heredodegenerative disorders. They may be caused by impaired energy metabolism, impaired systemic metabolism, storage of noxious substances, oligonucleotid repeats and other processes. Pseudodystonias mimic dystonia and include psychogenic dystonia and various orthopedic, ophthalmologic, vestibular, and traumatic conditions. Unusual manifestations, unusual age of onset, suspect family history, suspect medical history, and additional signs may indicate nonprimary dystonia. If they are suspected, etiological clarification becomes necessary. Unfortunately, potential etiologies are legion. Diagnostic algorithms can be helpful. Treatment of nonprimary dystonias, with few exceptions, does not differ from treatment of primary dystonias. The most effective treatment for focal and segmental dystonias is local botulinum toxin injections. Deep brain stimulation of the globus pallidus internus is effective for generalized dystonia. Antidystonic drugs, including anticholinergics, tetrabenazine, clozapine, and gamma-aminobutyric acid receptor agonists, are less effective and often produce adverse effects. Dopamine is extremely effective in dopa-responsive dystonia. The Bertrand procedure can be effective in cervical dystonia. Other peripheral surgery, including myotomy, myectomy, neurotomy, rhizotomy, ramizectomy, and accessory nerve neurolysis, has largely been abandoned. Central surgery other than deep brain stimulation is obsolete. Adjuvant therapies, including orthoses, physiotherapy, ergotherapy, behavioral therapy, social support, and support groups, may be helpful. Analgesics should also be considered where appropriate.

Orofacial movement disorders

This article reviews three poorly recognized yet relatively common presentations of hyperactive orofacial movement disorders: oromandibular dystonia, orofacial dyskinesia, and drug-induced extrapyramidal syndrome reactions. Orofacial movement disorders are often misdiagnosed as temporomandibular disorders, hence understanding these conditions is pertinent for the practitioner treating orofacial pain. Aspects of epidemiology, etiology, pathophysiology, clinical presentation, and diagnosis are discussed along with treatment considerations for these orofacial movement disorders.

Focal hand dystonia secondary to Basal Ganglia germinoma

Descriptions of symptomatic focal dystonia caused by focal lesions of the central nervous system (CNS) are rare in the literature. We report a 9-year-old child who experienced sudden-onset left-hand dystonia for 6 months. Brain magnetic resonance imaging showed a mass lesion involving the putamen, globus pallidus, head of caudate, and the anterior limb of the internal capsule. Histopathological and immunocytochemical examinations of the mass revealed features characteristic of malignant germinoma. CNS germinoma in the basal ganglia is very rare. Combining previous reports in the literature with the anatomical and clinical presentation of our case suggests that this phenomenon results from disruption of the pathways within and adjacent to the basal ganglia.

Glucose hypermetabolism in the thalamus of patients with essential blepharospasm

Essential blepharospasm (EB) is classified as a form of focal dystonia characterized by involuntary spasms of the musculature of the upper face. The basic neurological process causing EB is not known. The purpose of this study was to investigate cerebral glucose metabolism in patients with EB whose symptoms were suppressed by an injection of botulinum-A toxin. Earlier studies were confounded by sensory feedback activities derived from dystonic symptom itself. Cerebral glucose metabolism was examined by positron emission tomography (PET) with (18)F-fluorodeoxyglucose (FDG) in 25 patients (8 men and 17 women; age 52.6 +/- 10.1 years) with EB. The patients were awake but with the spasms suppressed by an injection of botulinum-A toxin. Thirty-eight normal volunteers (14 men and 24 women; age 58.2 +/- 7.3 years) were examined as controls. The difference between the two groups was examined by statistical parametric mapping (SPM99). A significant increase in the glucose metabolism was detected in the thalamus and pons in the EB patients. Hyperactivity in the thalamus may be a key pathophysiological change common to EB and other types of focal dystonia. The activity of the striatum and cerebellum are likely to be sensory dependent.

Sporadic rapid-onset dystonia-parkinsonism syndrome: failure of bilateral pallidal stimulation

We report on a woman who had a severe sporadic nonprogressive dystonia-parkinsonism syndrome with rapid onset of symptoms at age 21. Secondary causes for dystonia were ruled out. No response to levodopa/carbidopa was seen. The patient fulfilled all diagnostic criteria of rapid-onset dystonia-parkinsonism, except for autosomal-dominant inheritance. Bilateral deep brain stimulation of the globus pallidus failed to alleviate her symptoms.

Patterns of EMG-EMG coherence in limb dystonia

Dystonia of the limbs may be due to a wide range of aetiologies and may cause major functional limitation. We investigated whether the previously described pathological 4 to 7 Hz drive to muscles in cervical dystonia is present in patients with aetiologically different types of dystonia of the upper and lower limbs. To this end, we studied 12 symptomatic and 4 asymptomatic carriers of the DYT1 gene, 6 patients with symptomatic dystonia due to focal basal ganglia lesions, and 11 patients with fixed dystonia, a condition assumed to be mostly psychogenic in aetiology. We evaluated EMG-EMG coherence in the tibialis anterior (TA) of these and 15 healthy control subjects. Ten of 12 (83%) of symptomatic DYT1 patients had an excessive 4 to 7 Hz common drive to TA, evident as an inflated coherence in this band. This drive also involved the gastrocnemius, leading to co-contracting electromyographic bursts. In contrast, asymptomatic DYT1 carriers, patients with symptomatic dystonia, patients with fixed dystonia, and healthy subjects showed no evidence of such a drive or any other distinguishing electrophysiological feature. Moreover, the pathological 4 to 7 Hz drive in symptomatic DYT1 patients was much less common in the upper limb, where it was only present in 2 of 6 (33%) patients with clinical involvement of the arms. We conclude that the nature of the abnormal drive to dystonic muscles may vary according to the muscles under consideration and, particularly, with aetiology.

Eyelid movements in health and disease. The supranuclear impairment of the palpebral motility

The eyelid movements are mediated mainly by the orbicularis oculi (OO) and the levator palpebrae superioris (LPS) muscles. Dissociated upper lid functions exhibit different counterbalanced action of these muscles, and in blinking they show a strictly reciprocal innervation. The disturbance of this close LPS-OO relationship likely leads to many of the central lid movement disorders. Three groups of supranuclear motor impairment of lid movements are considered: the disorders of the lid-eye movements' coordination, the disturbances of blinking and lid "postural" maintenance, and the alteration of voluntary lid movements. Nuclei of the posterior commissure control the inhibitory modulation of LPS motor-neuronal activity and they are involved in the lid-eye coordination disorders such as lid retraction, which is observed in the Parinaud's syndrome and also in parkinsonism and progressive supranuclear palsy. Spontaneous (SB) and reflex blinking consist of two components: the inhibition of the basal tonic LPS activity, which keeps the eyes open, and the concurrent activation of the OO muscles. LPS inhibition precedes and outlasts the OO activation. This normal configuration is impaired in parkinsonism and blepharospasm (BSP). SB shows a highly interindividual rate variation (among 10-20 per minute in adults) and abnormal blink rates occur in neurological diseases related to dopaminergic transmission impairments. Lid postural abnormalities include involuntary eyelid closure, which is usually associated with inability to open the eyes. Two major disorders share these two aspects: BSP and blepharocolysis (BCO). BSP consists of an involuntary overactivity of the OO, with LPS co-contraction activity, and is expressed as frequent and prolonged blinks, clonic bursts, prolonged tonic contraction or a blend of all of them. BCO (commonly named "so-called lid opening apraxia") is an overinhibition of the LPS with no evidence of ongoing OO activity. BSP and BCO occur in many instances of idiopathic dystonias and basal ganglia diseases and, less frequently, in rostral brainstem lesions. Both may coincide in the same patient. Voluntary lid movement disorders comprise the impairment of Bell's phenomenon, the voluntary eyelid closure palsy and the so-called cerebral ptosis, all related to lesions of frontal cortical areas and/or the corticospinal system.

Positron emission tomography scanning in essential blepharospasm

PURPOSE

To localize in the brain using positron emission tomography neuroimaging with (18)fluorodeoxyglucose [PET ((18)FDG)] differences in glucose metabolism between patients with essential blepharospasm (EB) and controls.

DESIGN

Prospective case-control study.

METHODS

Positron emission tomography neuroimaging with (18)fluorodeoxyglucose was performed in 11 patients with EB and 11 controls matched for age and gender. Global analysis of images was used to localize differences in glucose metabolism between groups.

RESULTS

Multiple cortical and subcortical abnormalities were observed in EB patients in comparison with controls. Cortical areas with the largest and most significant clusters of increased glucose uptake were the inferior frontal gyri, right posterior cingulate gyrus, left middle occipital gyrus, fusiform gyrus of the right temporal lobe, and left anterior cingulate gyrus. Cortical areas with the largest and most significant clusters of decreased glucose uptake were the inferior frontal gyri, ventral to the area of increased glucose metabolism. Subcortical abnormalities, consisting of increased glucose uptake, involved the right caudate and consisting of decreased glucose uptake, involved the left inferior cerebellar hemisphere and thalamus.

CONCLUSIONS

Global analysis of positron emission tomography neuroimaging with (18)fluorodeoxyglucose neuroimaging in EB patients in comparison with controls demonstrates a pattern of abnormalities involving several cortical and subcortical areas that control blinking, including the inferior frontal lobe, caudate, thalamus, and cerebellum.

Diminished striatal [123I]iodobenzovesamicol binding in idiopathic cervical dystonia

Striatal dysfunction is thought to underlie many dystonias. We used [(123)I]iodobenzovesamicol single-photon emission computed tomography imaging to determine the density of cholinergic terminals in the striatum and other brain regions in 13 subjects with idiopathic cervical dystonia. Striatal [(131)I]iodobenzovesamicol binding was reduced. These results support a role for striatal dysfunction in idiopathic dystonias and suggest diminished striatal cholinergic interneuron density in cervical dystonia.

Treatment of dystonia in striatal necrosis caused by Mycoplasma pneumoniae

We report on an 8-year-old male with bilateral striatal necrosis secondary to Mycoplasma pneumoniae respiratory infection. This patient has been remarkable for persistent severe dystonia that has been difficult to treat. We share our experience of beneficial responses to multimodal treatment, including moderate doses of trihexyphenidyl, botulinum toxin, and intrathecal baclofen.

The natural history and treatment of acquired hemidystonia: report of 33 cases and review of the literature

OBJECTIVE

To evaluate the natural history and response to treatment in hemidystonia.

METHODS

190 Cases of hemidystonia were identified; 33 patients in this series and 157 from the world literature. Data was collected on aetiology, age of onset, latency, lesion location, and response to treatment.

RESULTS

The most common aetiologies of hemidystonia were stroke, trauma, and perinatal injury. Mean age of onset was 20 years in this series and 25.7 years in the literature. The average latency from insult to dystonia was 4.1 years in this series and 2.8 years in the literature, with the longest latencies occurring after perinatal injury. Basal ganglia lesions were identified in 48% of cases in this series and 60% of the cases in the literature, most commonly involving the putamen. Patients experienced benefit from medical therapy in only 26% of medication trials in this series and in only 35% of trials in the literature. In the patients reported here, the benzodiazepines clonazepam and diazepam were the most effective medications with 50% of trials resulting in at least some benefit. In the literature, anticholinergic drugs were most effective with 41% of trials resulting in benefit. Surgery was successful in five of six cases in this series and in 22 of 23 cases in the literature. However, in 12 cases, results were transient.

CONCLUSIONS

The most common cause of hemidystonia is stroke, with the lesion most commonly involving the basal ganglia. Hemidystonia responds poorly to most medical therapies, but some patients may benefit from treatment with benzodiazepines or anticholinergic drugs. Surgical therapy may be successful but benefit is often transient.

Dystonia and parkinsonism

Parkinsonism and dystonia may coexist in a number of neurodegenerative, genetic, toxic, and metabolic disorders and as a result of structural lesions in the basal ganglia. Parkinson's disease (PD) and the 'Parkinson-plus' syndromes (PPS) account for the majority of patients with the parkinsonism-dystonia combination. Dystonia, particularly when it involves the foot, may be the presenting sign of PD or PPS and these disorders should be suspected when adults present with isolated foot dystonia. Young age, female gender, and long disease duration are risk factors for PD-related dystonia, but dystonia in patients with PD is usually related to levodopa therapy. The mechanism of dystonia in PD is not well understood and the management is often challenging because levodopa and other dopaminergic agents may either improve or worsen dystonia. Other therapeutic strategies include oral medications (baclofen, anticholinergics and benzodiazepines), local injections of botulinum toxin, intrathecal baclofen, and surgical lesions or high frequency stimulation of the thalamus, globus pallidus, or subthalamus.

Dystonia in Wilson's disease

The frequency and type of dystonic movements, as well as brain abnormalities, as depicted with magnetic resonance imaging (MRI), which might correlate with dystonia, were studied in 27 consecutive patients with a neurologic form of Wilson's disease (WD) and optimized treatment. Dystonia was found in 10 patients (37%), being generalized in half of them, while two patients had segmental, two patients multifocal dystonia, and one patient bilateral foot dystonia. Dystonia was a presenting sign in four patients and developed later in the course of the disease in six patients, despite the administered therapy for WD. Putamen was the only structure significantly more frequently lesioned in dystonic (80%) in comparison to WD patients without dystonia (24%), suggesting a relation between abnormalities in this brain region and dystonic movements in WD.

Lesch-Nyhan disease and the basal ganglia

The purpose of this review is to summarize emerging evidence that the neurobehavioral features of Lesch-Nyhan disease (LND), a developmental disorder caused by congenital deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT), may be attributable to dysfunction of the basal ganglia. Affected individuals have severe motor disability described by prominent extrapyramidal features that are characteristic of dysfunction of the motor circuits of the basal ganglia. They also display disturbances of ocular motility, cognition, and behavioral control that may reflect disruption of other circuits of the basal ganglia. Though neuropathologic studies of autopsy specimens have revealed no obvious neuroanatomical abnormalities in LND, neurochemical studies have demonstrated 60-90% reductions in the dopamine content of the basal ganglia. In addition, recent PET studies have documented significant reductions in dopamine transporters and [18F]fluorodopa uptake in the basal ganglia. These findings support the proposal that many of the neurobehavioral features of LND might be related to dysfunction of the basal ganglia.

D2 receptor binding in dopa-responsive dystonia

We have studied dopamine D2 receptor binding by [11C]raclopride positron emission tomography in 14 patients with dopa-responsive dystonia (DRD). Data were compared with 16 levodopa-treated patients with Parkinson's disease (PD) and 26 healthy controls. The results revealed an elevated [11C]raclopride binding index in the putamen and caudate nucleus of DRD patients compared with controls as well as a significant elevation in the caudate nucleus compared with PD patients. The increase of [11C]raclopride binding may be interpreted either as reduced tracer displacement by endogenous dopamine, or as an alteration of the receptor features due to chronic dopamine deficiency. The difference in [11C]raclopride binding in DRD and PD patients in the caudate nucleus suggests that this structure may be of pathophysiological relevance in the presentation of the clinical features of both diseases.