Cerebral arteriovenous malformations and movement disorders

Hemichorea secondary to isolated temporal infarction with severe middle cerebral artery stenosis: a case report and review of literature

BACKGROUND

Hemichorea typically results from a contralateral subthalamic nuclei (STN) lesion, although it has been reported in the cortex in a minority of cases. However, to our best knowledge, there are no documented cases in literature of hemichorea occurring as a secondary condition to an isolated temporal stroke.

CASE PRESENTATION

We present a case of an elderly female who sustained a sudden onset of hemichorea in her right extremities, predominantly in the distal region, lasting over a period of two days. Brain diffuse weighted image (DWI) demonstrated a high signal in the temporal region, while magnetic resonance angiography (MRA) revealed severe stenosis of the middle cerebral artery. During the symptomatic phase, computed tomography perfusion (CTP) revealed delayed perfusion in the left middle cerebral artery territory, characterized by the time-to-peak (TTP) measure. Based on the results of her medical history and laboratory tests, we were able to rule out the possibility of infectious, toxic, or metabolic encephalopathy. Her symptoms gradually improved with antithrombotic and symptomatic treatment.

CONCLUSIONS

It is important to recognize and consider acute onset hemichorea as an initial symptom of stroke to avoid misdiagnosis and delays in appropriate treatment. Further research on temporal lesion that lead to hemichorea is warranted to gain a better understanding of the underlying mechanisms.

Endothelial Rbpj Is Required for Cerebellar Morphogenesis and Motor Control in the Early Postnatal Mouse Brain

Intercellular influences are necessary for coordinated development and function of vascular and neural components in the brain. In the early postnatal period after birth, the mammalian cerebellum undergoes extensive morphogenesis - developing its characteristic lobules, organizing its diverse cell types into defined cellular layers, and establishing neural circuits that support cerebellar function, such as coordinated movement. In parallel, the cerebellar vasculature undergoes extensive postnatal growth and maturation, keeping pace with the expanding neural compartment. Endothelial deletion of Rbpj leads to neurovascular abnormalities in mice, including arteriovenous (AV) shunts that supplant capillaries and instead direct high-pressure/high-flow arterial blood directly to veins. Gross and histopathological cerebellar abnormalities, associated with these Rbpj-mediated brain AV malformations (AVMs), led to our hypothesis that early postnatal morphogenesis and lamination of cerebellum was perturbed in mice harboring endothelial Rbpj deficiency from birth. Here, we show that endothelial Rbpj-mutant mice developed enlarged vascular malformations on the cerebellar surface, by 2-week post-Rbpj deletion. In addition, outgrowth of cerebellar lobules was impaired through decreased cell proliferation, but not increased apoptosis, in the external granule layer. Molecular layer thickness was reduced, and the Purkinje layer was affected, by decreased Purkinje cell number, primary dendrite length, and dendritic arbor density. Endothelial deletion of Rbpj also led to impaired motor behaviors, consistent with abnormal cerebellar morphogenesis and lamination. Thus, our data suggest that Rbpj is required, in early postnatal vascular endothelium, to ensure proper cerebellar outgrowth, morphogenesis, and function in mice.

Hypofractionated stereotactic radiosurgery in a large bilateral thalamic and Basal Ganglia arteriovenous malformation

Purpose. Arteriovenous malformations (AVMs) in the basal ganglia and thalamus have a more aggressive natural history with a higher morbidity and mortality than AVMs in other locations. Optimal treatment—complete obliteration without new neurological deficits—is often challenging. We present a patient with a large bilateral basal ganglia and thalamic AVM successfully treated with hypofractionated stereotactic radiosurgery (HFSRS) with intensity modulated radiotherapy (IMRT). Methods. The patient was treated with hypofractionated stereotactic radiosurgery to 30 Gy at margin in 5 fractions of 9 static fields with a minimultileaf collimator and intensity modulated radiotherapy. Results. At 10 months following treatment, digital subtraction angiography showed complete obliteration of the AVM. Conclusions. Large bilateral thalamic and basal ganglia AVMs can be successfully treated with complete obliteration by HFSRS with IMRT with relatively limited toxicity. Appropriate caution is recommended.

Clinical and morphological determinants of focal neurological deficits in patients with unruptured brain arteriovenous malformation

OBJECTIVE

Some patients with brain arteriovenous malformation (BAVM) present with focal neurological deficits (FNDs) unrelated to clinically discernable seizure activity or hemorrhage. The aim of this study is to determine demographic and morphological AVM characteristics associated with FNDs.

METHODS

The 735 patients of the prospective Columbia AVM Databank were analyzed. Univariate and multivariate statistical models were used to test the association of demographic (age, gender), and morphological characteristics (BAVM size, anatomic location, arterial supply, venous drainage pattern, venous ectasia) with the occurrence of FNDs at the time of initial BAVM diagnosis.

RESULTS

Fifty-three patients (7%, mean age 40+/-16years, 70% women) presented with FNDs. The multivariate logistic regression model revealed an independent association of FNDs with increasing age (OR 1.03; 95%-CI 1.00-1.05), female gender (OR 2.14; 95%-CI 1.15-3.97), deep brain location (OR 2.46; 95%-CI 1.24-4.88), brainstem location (OR 5.62; 95%-CI 1.65-19.23), and venous ectasia (OR 1.91; 95%-CI 1.01-3.64). No association was found for BAVM size, lobar location, arterial supply and venous drainage pattern.

INTERPRETATION

Focal neurologic deficits unrelated to seizures or hemorrhage are a rare initial presentation of BAVMs. The predominance of FNDs among brainstem and deeply located BAVMs and the lack of a significant association of BAVM size with FNDs indicate selective white matter pathway-specific vulnerability, the association with patient age a time dependent effect. The higher frequency of FNDs among women suggests gender-specificity of brain tissue vulnerability.

Concurrent hemichorea and migrainous aura--a perfusion study on the basal ganglia using xenon-computed tomography

A variety of etiologies underlie the neurophysiological imbalance resulting in chorea. We report a 57-year-old woman with a long-history of migraine who suddenly experienced concurrent scintillating scotoma and rapid involuntary movement of her neck and right extremities. Diffusion-weighted magnetic resonance imaging (MRI) failed to detect any fresh ischemic and/or hemorrhagic lesions. Xenon-computed tomography (CT) disclosed gross reduction in the cerebral blood flow (CBF) of the left occipital area. With precise mapping to the brain atlas, extreme hyperperfusion in the motor thalamus was found on the left side. Asymmetrical CBF reduction of the left subthalamic nucleus was also noted. Her symptoms gradually improved and completely disappeared within 15 days. Repeated xenon-CT 1 month post-onset demonstrated normalized CBF in the affected areas. Our study suggests that vascular event underlies the migrainous aura in this case and secondarily provokes a loss of inhibitory control of the motor thalamus resulting in the manifestation of hemichorea.

Two cases of hemiballism-hemichorea with T1-weighted MR image hyperintensities

Two cases of hemiballism-hemichorea have been reported in woman patients with hyperglycemia; this was a feature of striatal hyperintensity on the T1-weighted MRI. In the first case, strict management of diabetes and treatment with pimozide effectively suppressed the movement disorder. The Z-score Imaging System revealed hyperperfusion in the bilateral dentate nuclei, left striatum, and bilateral motor cortices. In the second case, painful hemiballism-hemichorea limb, followed by the upper limb. The severity of HB-HC corresponded to the expansion of the striatal lesion. The mechanism of HB-HC by using statistical cerebral blood flow evaluation has also been discussed.

Symptomatic segmental dystonia from a cavernous angioma in the centrum semiovale

We describe a 68 year-old Chinese man who presented with segmental dystonia involving the neck and right upper limb, which was exacerbated with action. EEG and MRI of the cervical spine were unremarkable, but MRI of the brain revealed a small cavernous angioma measuring one centimeter in diameter in the left centrum semiovale. The dystonia was ameliorated but not abolished with trihexyphenidyl. Arteriovenous malformations have been described to cause movement disorders, but dystonia has not previously been reported in association with cavernous angiomas. A search of the literature revealed one report of a patient with chorea arising from a cavernous angioma. This interesting case illustrates how an uncomplicated cavernous angioma can rarely cause segmental dystonia and highlights the importance of neuroimaging in patients with late-onset movement disorders.

Focal dystonia after removal of a parietal meningioma

A patient presented at the age of 50 years with a right-sided, writing-specific dystonia which settled without treatment. Ten years later she developed focal seizures affecting the right leg and occasionally spreading to the right arm. A left parietal meningioma was removed and 2 years later she developed dystonic movements of her right hand. Gliotic changes were seen on magnetic resonance imaging in the superficial left parietal lobe. Mechanisms involved in the generation of dystonia associated with cortical injury are discussed.

Arm chorea secondary to an unruptured giant aneurysm

We describe the case of a 20-year-old male who developed right-arm choreic movements secondary to a giant unruptured aneurysm impinging upon the left thalamus, putamen, globus pallidus, cerebral peduncle, midbrain, and subthalamic nucleus. The aneurysm was treated successfully with coils and a supraclinoid balloon. Abnormal movements initially failed to ameliorate, but within a few months, it was possible to discontinue symptomatic haloperidol therapy, with only mild residual abnormal movements.

Severe generalized dystonia due to primary putaminal degeneration: case report and review of the literature

Putaminal lesions of a variety of etiologies may cause secondary dystonia. We report on a case of primary putaminal degeneration as a cause of severe childhood-onset generalized dystonia and review the literature of the pathology of dystonia. A 44-year-old patient with severe generalized childhood-onset dystonia and macrocephaly underwent neurological evaluation and neuropathological examination. Neurological examination was normal apart from dystonia and signs referable to prior cryothalamotomy. Workup for metabolic and genetic causes of dystonia was negative. Neuroimaging showed severe bilateral putaminal degeneration, which subsequently correlated with the neuropathological findings of gliosis, spongiform degeneration, and cavitation. The substantia nigra pars compacta contained a normal number of neurons but decreased tyrosine hydroxylase immunoreactivity. There were no histopathological markers of other metabolic or degenerative diseases.