Asterixis in the leg induced by anterior cerebral artery infarction.

Asterixis commonly occurs in a patient with metabolic encephalopathy, whereas focal brain lesions such as thalamus, cerebellum, or frontal area also cause focal or unilateral asterixis in the arms. We report a novel case of asterixis in the leg after unilateral anterior cerebral artery territory infarction. A 76-year-old man was admitted with sudden-onset mild right leg weakness and postural instability due to knee buckling. He was diagnosed with ischemic stroke in the left prefrontal area and cingulated gyrus by brain magnetic imaging. Needle electromyography of the right vastus lateralis muscle while standing showed intermittent periods of EMG silence, consistent with asterixis. There were no abnormal involuntary movements in the upper extremities. This case suggests that gait disturbance or postural instability after structural lesions in the prefrontal area may be directly related to asterixis in the leg, not in the arm associated with postural failure.

Ginkgotoxin Induced Seizure Caused by Vitamin B6 Deficiency.

Although ginkgo is commonly used as an alternative treatment for memory loss, Alzheimer's dementia and peripheral circulatory disturbances, it is also known to cause neuronal symptoms due to ginkgotoxin (4'-methoxypyridoxine or B6 antivitamin). We experienced a case of a 51-year-old female patient with generalized tonic clonic seizure and postictal confusion after eating large amounts of ginkgo nuts. Blood vitamin B6 level was decreased. After conservative treatment and pyridoxine medication, her mental symptoms were resolved completely and no seizures recurred.

Valproic Acid-induced Hyperammonemic Encephalopathy Promoted by Levetiracetam.

Encephalopathy resulting from the administration of levetiracetam (LEV) is a rare occurrence. We experienced a patient receiving LEV treated with valproic acid (VPA) for partial seizures with secondary generalization, following which she developed hyperammonemic encephalopathy and showed complete recovery after the drug was withdrawan. LEV is able to promote hyperammonemic encephalopathy when added to VPA.

Cerebral infarction caused by a tortuous subclavian artery: a case report.

Tortuous arteries are common clinical observation. Although mild tortuosity is asymptomatic, severe tortuosity can lead to ischemic attack in several organs. With advances in imaging technology, an increasing number of tortuous vessels have been detected. The purpose of this report is to describe a case of acute cerebral infarction due to tortuous subclavian artery and to review the literature.

Acute hepatic encephalopathy presenting as cortical laminar necrosis: case report.

We report on a 55-year-old man with alcoholic liver cirrhosis who presented with status epilepticus. Laboratory analysis showed markedly elevated blood ammonia. Brain magnetic resonance imaging (MRI) showed widespread cortical signal changes with restricted diffusion, involving both temporo-fronto-parietal cortex, while the perirolandic regions and occipital cortex were uniquely spared. A follow-up brain MRI demonstrated diffuse cortical atrophy with increased signals on T1-weighted images in both the basal ganglia and temporal lobe cortex, representing cortical laminar necrosis. We suggest that the brain lesions, in our case, represent a consequence of toxic effect of ammonia.

Hot cross bun sign following bilateral pontine infarction: a case report.

The hot cross bun sign is characterized by cruciform T2 signal hyperintensity in the pons and has been reported to be a specific but not pathognomic for multiple system atrophy. It reflects degeneration of pontine neurons and transverse pontocerebellar fibers, regardless of the underlying pathogenic process. Here, we report a case of hot cross bun sign following bilateral pontine infarction due to Wallerian degeneration of the pontocerebellar fibers.

Thrombocytopenia associated with levodopa treatment.

There were few cases of thrombocytopenia associated with levodopa. Herein, we report a patient with Parkinson's disease, who suffered thrombocytopenia related to long-term use of levodopa.

Diffusion weighted imaging findings in the acute lateral medullary infarction.

BACKGROUND AND PURPOSE: Negative findings on diffusion-weighted imaging (DWI) does not exclude the possibility of brainstem infarction, particularly in the acute stage of medullary lesion. Our aim was to investigate the false-negative rate of DWI in patients with acute lateral medullary infarction. METHODS: We applied DWI to 26 patients with a clinical diagnosis of lateral medullary infarction within 72 h of the onset. We assessed relationships between initial DWI findings and time-to-MRI (the time between onset of symptoms and initial DWI), number of clinical symptoms and signs, and final lesion volume. RESULTS: There were 8 cases (31%) of false negatives in the initial DWI results. The occurrence of false-negative DWI findings decreased significantly as the time-to-MRI increased (P=0.014). However, the false-negative rate was not significantly correlated with the number of clinical symptoms and signs or the final lesion volume. CONCLUSIONS: The diagnosis of lateral medullary infarction should not be ruled out on the basis of early negative DWI. To confirm the lesion, follow-up DWI or further MRI should be performed in cases with early negative DWI results.