Reversible striatal hypermetabolism in chorea associated with moyamoya disease: a report of two cases

Late-onset, first-ever involuntary movement after successful surgical revascularization for pediatric moyamoya disease - Report of two cases

Background

A small number of children with Moyamoya disease develop involuntary movements as an initial presentation at the onset, which usually resolves after effective surgical revascularization. However, involuntary movements that did not occur at the onset first occur after surgery in very rare cases. In this report, we describe two pediatric cases that developed involuntary movements during the stable postoperative period after successful surgical revascularization.

Case Description

A 10-year-old boy developed an ischemic stroke and successfully underwent combined bypass surgery. However, he developed chorea six months later. Another 8-year-old boy developed a transient ischemic attack and successfully underwent combined bypass surgery. However, he developed chorea three years later. In both cases, temporary use of haloperidol was quite effective in resolving the symptoms, and involuntary movements did not recur without any medication during follow-up periods of up to 10 years.

Conclusion

Postoperative first-ever involuntary movement is very rare in pediatric moyamoya disease, and the underlying mechanisms are still unclear, but a temporary, reversible imbalance of excitatory and inhibitory circuits in the basal ganglia may trigger the occurrence of these rare symptoms. Careful follow-up would be mandatory.

Disappearance of hemichorea as the initial presentation of moyamoya disease after revascularization surgery regardless of residual hypoperfusion evaluated by quantitative N-isopropyl-p-123I-iodoamphetamine SPECT

BACKGROUND AND IMPORTANCE

Although hypoperfusion of the basal ganglia or the frontal subcortical matter is suspected, the pathology of chorea in moyamoya disease remains unclarified. Herein, we report a case of moyamoya disease presenting with hemichorea and evaluate pre- and postoperative perfusion using single photon emission computed tomography with N-isopropyl-p-¹²³I-iodoamphetamine (¹²³I-IMP SPECT).

CLINICAL PRESENTATION

An 18-year-old woman presented with choreic movement of her left limbs. Magnetic resonance imaging revealed an ivy sign, and ¹²³I-IMP SPECT demonstrated decreased cerebral blood flow (CBF) and cerebral vascular reserve (CVR) values in the right hemisphere. The patient underwent direct and indirect revascularization surgery to improve cerebral hemodynamic impairment. The choreic movements entirely resolved immediately after surgery. Although CBF and CVR values in the ipsilateral hemisphere demonstrated by quantitative SPECT increased, these did not reach the normal values threshold.

CONCLUSION

Choreic movement in moyamoya disease may be related to cerebral hemodynamic impairment. Further studies are required to elucidate its pathophysiological mechanisms.

Periodic electroencephalographic discharges and epileptic spasms involve cortico-striatal-thalamic loops on Arterial Spin Labeling Magnetic Resonance Imaging

Periodic discharges are a rare peculiar electroencephalogram pattern, occasionally associated with motor or other clinical manifestations, usually observed in critically ill patients. Their underlying pathophysiology remains poorly understood. Epileptic spasms in clusters and periodic discharges with motor manifestations share similar electroencephalogram pattern and some aetiologies of unfavourable prognosis such as subacute sclerosing panencephalitis or herpes encephalitis. Arterial spin labelling magnetic resonance imaging identifies localizing ictal and inter-ictal changes in neurovascular coupling, therefore assumed able to reveal concerned cerebral structures. Here, we retrospectively analysed ictal and inter-ictal arterial spin labelling magnetic resonance imaging in patients aged 6 months to 15 years (median 3 years 4 months) with periodic discharges including epileptic spasms, and compared these findings with those of patients with drug-resistant focal epilepsy who never presented periodic discharges nor epileptic spasms as well as to those of age-matched healthy controls. Ictal electroencephalogram was recorded either simultaneously with arterial spin labelling magnetic resonance imaging or during the close time lapse of patients' periodic discharges, whereas inter-ictal examinations were performed during the patients' active epilepsy but without seizures during the arterial spin labelling magnetic resonance imaging. Ictal arterial spin labelling magnetic resonance imaging was acquired in five patients with periodic discharges [subacute sclerosing panencephalitis (1), stroke-like events (3), West syndrome with cortical malformation (1), two of them also had inter-ictal arterial spin labelling magnetic resonance imaging]. Inter-ictal group included patients with drug-resistant epileptic spasms of various aetiologies (14) and structural drug-resistant focal epilepsy (8). Cortex, striatum and thalamus were segmented and divided in six functional subregions: prefrontal, motor (rostral, caudal), parietal, occipital and temporal. Rest cerebral blood flow values, absolute and relative to whole brain, were compared with those of age-matched controls for each subregion. Main findings were diffuse striatal as well as cortical motor cerebral blood flow increase during ictal examinations in generalized periodic discharges with motor manifestations (subacute sclerosing panencephalitis) and focal cerebral blood flow increase in corresponding cortical-striatal-thalamic subdivisions in lateralized periodic discharges with or without motor manifestations (stroke-like events and asymmetrical epileptic spasms) with straight topographical correlation with the electroencephalogram focus. For inter-ictal examinations, patients with epileptic spasms disclosed cerebral blood flow changes in corresponding cortical-striatal-thalamic subdivisions (absolute-cerebral blood flow decrease and relative-cerebral blood flow increase), more frequently when compared with the group of drug-resistant focal epilepsies, and not related to Vigabatrin treatment. Our results suggest that corresponding cortical-striatal-thalamic circuits are involved in periodic discharges with and without motor manifestations, including epileptic spasms, opening new insights in their pathophysiology and new therapeutical perspectives. Based on these findings, we propose a model for the generation of periodic discharges and of epileptic spasms combining existing pathophysiological models of cortical-striatal-thalamic network dynamics.

Truncal dystonia with isolated middle cerebral artery ischemia: A case report of revascularization therapy for dystonia

Background:

Dystonia is a rare movement disorder with some cases being difficult to treat. Although dystonia can occur as a symptom of moyamoya disease, few studies have reported truncal dystonia occurring with middle cerebral artery (MCA) stenosis. Here, we report a case of truncal dystonia with MCA occlusion.

Case Description:

The patient was a 48-year-old female clerical worker who lived alone. An abnormal cervical posture initially appeared 7 years before (right flexion). Symptoms improved with medication and botulinum toxin injection. Five years before this report, her symptoms worsened, so the dose of oral medication was increased and botulinum treatment was performed, but the symptoms did not improve. The patient showed decreased cerebral blood flow (CBF) in the cortical areas but not in the basal ganglia. We performed superficial temporal artery-MCA bypass surgery because we believed that the dystonia was due to right MCA stenosis. The patient’s symptoms improved immediately after surgery, except for her mild cervical backbend. Seven months after the surgery, the patient’s involuntary movements showed further improvement, and symptoms have not worsened even after 2 years.

Conclusion:

Revascularization therapy improved CBF and truncal dystonia and could be a viable treatment option for dystonia with ischemia in the MCA region. Extensive cerebral ischemia can result in cortical inhibition loss or over-adapted cerebral plasticity and cause dystonia. Revascularization therapy may be useful for patients with dystonia and decreased CBF in the MCA region.

Oro-mandibular dystonia in pediatric moyamoya disease: Two cases report

Background:

In this report, we describe rare two pediatric cases that developed oro-mandibular dystonia due to moyamoya disease.

Case Description:

A 7-year-old boy presented with oro-mandibular dystonia and transient weakness of the left extremities, and was diagnosed as moyamoya disease. Another 7-year-old boy developed oro-mandibular dystonia alone and was diagnosed as moyamoya disease. In both, cerebral blood flow (CBF) was markedly decreased in the involved hemispheres, including the basal ganglia and cerebral cortex. They successfully underwent combined bypass surgery and experienced no further attacks of oromandibular dystonia during follow-up periods. CBF almost normalized through surgical collaterals through direct and indirect bypass.

Conclusion:

When treating patients with oro-mandibular dystonia, moyamoya disease should be listed as one of the differential diseases. The underlying mechanism of oro-mandibular dystonia in moyamoya disease is still unclear, but persistent cerebral ischemia in the basal ganglia and/or parietal lobe may play a key role to induce this rare symptom.

Corticostriatal Hypermetabolism in Moyamoya Disease-Induced Hemichorea: Two Case Reports and a Literature Review

Moyamoya disease (MMD) is a rare cause of chorea, and its pathophysiological mechanism remains unclear. We explore the use of cerebral positron emission tomography (PET) to study brain functional connectivity in 2 patients with MMD-induced hemichorea. Abnormal metabolism of brain was analyzed by ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET images. Dopamine transporters (DAT) PET evaluated the integrity of the cerebral dopamine system. A comprehensive systemic literature search of the PubMed database was also conducted. The ¹⁸F-FDG imaging of our patients showed no responsible hypometabolism in affected brain areas, while hypermetabolism in the affected caudate nucleus, putamen and fronto-parietal areas could be seen. DAT PET imaging was normal in patient 1 (a 23-year-old woman), while remarkably reduced DAT binding was seen in the left striatum of patient 2 (a 48-year-old woman). The literature review of 9 publications revealed that 11 patients who underwent single photon emission computed tomography (SPECT) showed cerebral hypoperfusion in the cortex and subcortical area; ¹⁸F-FDG PET was performed in 3 cases, which revealed hypermetabolism in the affected striatum in 2 cases. These findings suggest that the striatal and cortical hypermetabolism in the first patient result from underactivity in indirect pathway from basal ganglia-thalamocortical circuits, causing increased activity of excitatory glutamatergic thalamostriatal and thalamocortical projection neurons. The collateral vessels in the basal ganglia might lead to disruption of normal basal ganglia signaling. A dominant left hemisphere with corpus callosal connections to the right basal ganglia resulting into left hemichorea is the most probable explanation for the second patient. We have identified abnormal functional connectivity in basal ganglia-thalamocortical circuits in patients with MMD-induced chorea highlighting the corticostriatal pathway plays an important role in the pathogenesis of MMD-induced chorea.

Asymmetric lenticulostriate arteries in patients with moyamoya disease presenting with movement disorder: three new cases

OBJECTIVE

Unilateral movement disorder associated with moyamoya disease is a rare finding and the mechanism remains to be fully elucidated. Theories postulated include contralateral cerebral ischemic or hemorrhagic lesions, and/or hypoperfusion. However, few studies have reported such patients without contralateral lesions nor hypoperfusion. This study aimed to explore the potential mechanism of those who had neither contralateral cerebral lesions nor hypoperfusion.

METHODS

Neuroradiological features of lenticulostriate arteries in three cases with unilateral movement disorder associated with moyamoya disease who had neither contralateral lesions nor hypoperfusion were mainly analyzed.

RESULTS

Angiography and 3 T black-blood T1-weighted intracranial vessel wall imaging both demonstrated a significant asymmetry between bilateral lenticulostriate arteries qualitatively and quantitatively on admission. After one-year follow-up, two patients' vessel wall imaging indicated that the asymmetry diminished, and the symptoms spontaneously resolved.

CONCLUSION

This report demonstrated that patients with moyamoya disease with unilateral movement disorder who had neither contralateral lesions nor hypoperfusion may be related to the asymmetry between bilateral lenticulostriate arteries through basal ganglia.

Acute hemichorea in a young type 1 diabetic

Purpose/Aim: Acute movement disorder is an uncommon presenting symptom in patients with diabetes mellitus. We report a 20-year-old lady with poorly controlled type 1 diabetes, who presented with acute hemichorea and was found to have two rare diabetes-related central nervous complications of diabetic striatopathy and severe moyamoya disease (MMD).Materials and methods: She was treated with aggressive glycemic control; clonazepam and tetrabenazine as well as aspirin stroke prophylaxis for her MMD with resolution of her chorea 3 months later. She subsequently underwent cerebral revascularization surgery for her MMD.Results: This case highlights the possible differentials of acute chorea in diabetic patients and explores the pathophysiological mechanisms that may underlie both conditions in patients with type 1 diabetes.Conclusion: We recommend performing both magnetic resonance imaging (MRI) and magnetic resonance angiogram (MRA) brain for comprehensive evaluation of diabetic patients with new onset chorea. Prompt and accurate diagnosis is crucial as it guides prognostication and treatment strategies.

[Clinical findings of a patient with hemiballism after superficial temporal artery-middle cerebral artery anastomosis for idiopathic middle cerebral artery stenosis]

A 32-year-old woman experienced several episodes of transient numbness on the left side of her face and body. MR angiography revealed severe stenosis in the right middle cerebral artery (MCA). Abnormal collateral vessel networks were not observed, and idiopathic MCA stenosis was diagnosed. She underwent superficial temporal artery (STA)-MCA anastomosis of the right hemisphere. The surgery eliminated the transient ischemic attacks; however, she developed hemiballism in the left side of her face and left upper limb 2 weeks after the surgery. The ballism disappeared 1.5 years after onset without any treatments. A few patients with development of chorea after STA-MCA anastomosis has been reported in moyamoya disease, but not in those with MCA stenoses. It has been previsouly reported that the development of an involuntary movement might be associated with hypermetabolism in the contra lateral striatum after STA-MCA anastomosis. We considered that a similar mechanism may have caused hemiallism in our patient. We need to recognize that STA-MCA anastomosis could cause hemichorea or hemiballism.