Paroxysmal choreoathetosis precipitated by movement, sound and photic stimulation in a case of arterio-venous malformation in the parietal lobe

Cutaneous and Mixed Nerve Silent Period Recordings in Symptomatic Paroxysmal Kinesigenic Dyskinesia

Objective:

The underlying neurophysiologic mechanism responsible for secondary paroxysmal kinesigenic dyskinesia (PKD) is still unclear. Here, we study the pathogenesis of PKD in two patients with a demyelinating lesion in the spinal cord.

Methods:

Electromyogram recordings from affected arms of two patients with spinal cord lesions presenting PKD were compared with our laboratory standards. The cutaneous silent period (CuSP), mixed nerve silent period (MnSP) and coincidence period (CiP), defined as the common period between the CuSP and MnSP, were recorded.

Results:

A large decrease in the MnSP and disappearance of the CiP were observed in our patients, which was secondary to simultaneous extinction of the third portion of the MnSP, while the CuSP was normal. The MnSP and CiP were normal after recovery.

Conclusions:

Our results demonstrate that the third portion of the MnSP and the CuSP do not correspond to the same physiologic process. These findings suggest that PKD patients have abnormal spinal interneuron integration.

Involuntary movement induced by cerebral ischemia: pathogenesis and surgical outcome

Object. Involuntary movement is an uncommon manifestation of a transient ischemic attack. It may be induced by cerebral hemodynamic insufficiency, which is associated with several cerebral ischemic diseases. The authors present three cases of limb shaking due to moyamoya disease (MMD) or radiation-induced middle cerebral artery stenosis, and three additional cases of choreic movement due to MMD. Neuroimaging studies and surgical outcomes in these patients were retrospectively analyzed to investigate the pathological mechanism underlying the symptoms and to provide guidance for the management of involuntary movement disorders in cases of ischemic cerebral disease.

Methods. The patient population included two children and four adults with ages at presentation ranging between 7 and 50 years. The initial presenting symptoms were involuntary movements in all six cases. A magnetic resonance imaging finding common in all cases was a small infarct in the frontal corona radiata, which did not extend to the cortex or basal ganglia. A perfusion defect in the frontoparietal cortical and subcortical regions was demonstrated by singlephoton emission computerized tomography in all patients. Improved hemodynamic circulation in the frontoparietal cortical and subcortical regions occurred in parallel with clinical improvement following indirect or direct bypass surgery.

Conclusions. Ischemic dysfunction of the frontal cortical and subcortical motor pathways rather than that of the basal ganglia was suspected to be the cause of the observed contralateral involuntary movements. Direct and indirect bypass surgery can be used effectively to treat involuntary movements in patients with cerebral ischemic diseases such as MMD and in those with stenosis of an intracranial major artery.

Paroxysmal kinesigenic dyskinesias

The paroxysmal dyskinesias (PxDs) are involuntary, intermittent movement disorders manifested by dystonia, chorea, athetosis, ballismus or any combination of these hyperkinetic disorders. Paroxysmal kinesigenic dyskinesia (PKD), one of the four main types of PxD, involves sudden attacks of dyskinesias induced by voluntary movements. PKD most commonly occurs sporadically or as an autosomal-dominant familial trait with variable penetrance. Many causes of secondary PKD are being recognized. The exact pathophysiology of the PxDs awaits further elucidation, although basal ganglia dysfunction appears to play a major role. Although the precise gene remains unknown, genetic linkage studies have isolated loci on chromosome 16, which colocalizes with the locus for familial infantile convulsions and paroxysmal choreoathetosis in some studies. The episodic nature of PKD and its relationship with other episodic diseases, such as epilepsy, migraine, and episodic ataxia, suggests channelopathy as a possible underlying etiology. PKD may remit spontaneously, but it also responds well to anticonvulsants as well as some other agents.

Cerebral arteriovenous malformations and movement disorders

A series of six patients with movement disorders associated with cerebral arteriovenous malformations (AVM) is reported. The AVMs were classified according to the Spetzler-Martin classification as grade V (one patient), grade IV (four patients), and as grade III (one patient). One patient had action-induced hemidystonia caused by a contralateral frontoparietal AVM which compressed the putamen and was supplied partially by enlarged lenticulostriate arteries. Two patients presented with unilateral cortical tremor associated with contralateral high-frontal cortical/subcortical AVMs sparing the basal ganglia. Another patient developed hemidystonia and hemichorea-hemiballism after bleeding of a contralateral temporooccipital AVM and subsequent ischemia. Two patients had focal dystonia after thalamic and basal ganglia hemorrhage from AVMs. Five patients were operated on. The movement disorder was abolished in one patient postoperatively. Different mechanisms were identified that are relevant for the development of AVM-related movement disorders: mass effect, diaschisis, local parenchymal altered cerebral blood flow, and hemorrhagic or ischemic structural lesions.

Parietal motor syndrome: a clinical description in 32 patients in the acute phase of pure parietal strokes studied prospectively

We prospectively studied motor symptoms in 32 patients with CT- or MRI-proven acute pure parietal stroke. A transient, mild, 'pseudoparesis' of the hand (90%), was noted, improved by visual attention and prompting, associated with non-awareness of muscle power (53%), transient soft pyramidal signs (50%), unilateral akinesia (100%) and motor hemineglect (37%) in non-dominant lesions. Lower motoneurone-type atrophy was not observed in this acute phase. We called 'poikilotonia' the striking unpredictable variations in muscle tone, ranging from extreme hypertonia to hypotonia, found in all patients. When maintaining postures, patients showed large oscillations (100%), laterodeviation or levitation of the arm (60%), especially in the case of large or posterior lesions, or, occasionally (3%), motor persistence or even hemicatalepsy (3%). Limb kinetic and manipulatory apraxia, with inadequate organization and anticipation of motor sequences and synergies, motor arrests, perplexity, unrecognizable gestures and loss of bimanual coordination, was a constant finding (100%). Other apraxias (62%) and difficulty in copying intransitive gestures of the hand (84%) were associated with posterior lesions involving the supramarginal gyrus. When reaching towards objects, all patients showed abnormal anticipatory hand shaping, but visuomotor ataxia (3%) was only seen with bilateral posterior stroke. Sensory (70%) or pseudocerebellar (4%) ataxia, was seen in both anterior and posterior lesions. Avoidance behaviors (34%) were not uncommon, but had no localizing value. Of the dyskinesias, hand dystonia (84%) was frequent, but athetosis (16%), asterixis (15%), postural tremor (15%), myoclonus (9%) and stereotypia (9%), were uncommon. The abnormal eye movements were unilateral hypo-akinesia of exploratory saccades (43%), abnormal ipsilateral pursuit and contralateral optokinetic nystagmus in the case of posterior lesions, and oculomotor apraxia with bilateral posterior lesions. In conclusion, parietal motor syndrome can be recognized during bedside examination, and probably reflects the loss of multiple sensory feedback to motor programs, especially those directed to the extrapersonal space.

Hyperkinetic movement disorders during and after acute stroke: the Lausanne Stroke Registry

BACKGROUND AND OBJECTIVE

To study consecutive patients with acute or delayed hyperkinetic movement disorders in the Lausanne Stroke Registry.

METHODS

We have identified 29 patients with acute or delayed movement disorders among 2500 patients who had their first-ever acute stroke in the Lausanne Stroke Registry.

SETTING

Department of Neurology, Lausanne University Hospital.

RESULTS

Our patients presented with hemichorea-hemiballism (11 patients), hemidystonia (5 patients), stereotypias (2 patients), jerky dystonic unsteady hand (3 patients), asterixis (2 patients), initial limb-shaking (2 patients), bilateral tremor (1 patients), bilateral jaw myoclonus (1 patient), hemiakathisia (1 patient) and dysarthria-dyskinetic hand (1 patient). On neuroimaging a lesion was found in 25 of the 29 cases in the territory of the middle cerebral artery (7 deep, 2 superficial and 2 complete), the posterior cerebral artery (11 patients), both middle and posterior cerebral arteries (2 patients) or the anterior cerebral artery (1 patient). The jerky dystonic unsteady hand syndrome was associated with a specific lesion, an infarct in the territory of the posterior choroidal artery. Presumed small-vessel disease was the commonest cause of stroke (15 patients). Only 3 patients had persistent movements (> 6 months).

CONCLUSION

Hyperkinetic movement disorders are uncommon in acute stroke (1%), the commonest types being hemichorea-hemiballism and hemidystonia. These movement disorders are associated with stroke involving the basal ganglia and adjacent white matter in the territory of the middle or the posterior cerebral artery. The jerky dystonic unsteady hand syndrome is specifically associated with a small infarct in the territory of the posterior choroidal artery. The abnormal movements usually regress spontaneously.

Paroxysmal dyskinesias: clinical features and classification

We studied 46 patients with paroxysmal dyskinesia and classified them according to phenomenology, duration of attacks, and etiology. There were 13 patients, 7 females, who had paroxysmal kinesigenic dyskinesia (PKD), 10 with attacks lasting 5 minutes or less (short lasting) and 3 with attacks lasting longer than 5 minutes (long lasting). Twenty-six patients, 18 females, had paroxysmal nonkinesigenic dyskinesia (PNKD), 9 with short-lasting and 17 with long-lasting PNKD. Five patients, 3 females, had paroxysmal exertion-induced dyskinesia (PED), 3 with short-lasting PED and the other 2 with long-lasting PED. In addition, there was 1 patient with paroxysmal hypnogenic dyskinesia (PHD) and 1 with paroxysmal superior oblique myokymia. Only 2 patients, 1 with PKD and 1 with PHD, had family history of paroxysmal dyskinesias. No specific cause could be identified in 21 patients; in the other 23 patients the etiologies included the following: psychogenic (9 patients), cerebrovascular diseases (4), multiple sclerosis (2), encephalitis (2), cerebral trauma (2), peripheral trauma (2), migraine (1), and kernicterus (1). Nine of 10 (90%) patients with PKD improved with medications, mostly anticonvulsants, compared with only 7 of 19 (37%) with PNKD. This new classification, based chiefly on precipitating events, allowed appropriate categorization of the attacks in all our patients with paroxysmal dyskinesias.