Brachial Plexus Involvement of Myeloid Sarcoma Detected by Reconstruction Magnetic Resonance Neurography.

Myeloid sarcoma is a rare hematological disorder that presents as an extramedullary mass of immature myeloid precursors. We herein present the case of a 57-year-old man with a seven-month history of progressive weakness in the right upper extremity. Reconstruction magnetic resonance neurography showed a marked enlargement of the right brachial plexus. Fluorodeoxyglucose positron emission tomography revealed a radioactive lesion in the sacrum, in addition to the right brachial plexus, and a biopsy of the sacrum revealed myeloid sarcoma. The brachial plexus lesion was also regarded as myeloid sarcoma because of the treatment response. Isolated myeloid sarcoma involving the brachial plexus is very rare and its diagnosis is difficult as there was neither a history of leukemia nor bone marrow involvement in this patient. In this case, reconstructed magnetic resonance neurography was useful for detecting the brachial plexus mass lesion which led to an early diagnosis and good recovery.

Features of brain magnetic resonance imaging diffusion-weighted images of aortogenic embolic stroke.

BACKGROUND: The features of acute aortogenic embolic stroke on magnetic resonance diffusion-weighted imaging (DWI) have not been fully elucidated, so we compared patients with acute aortogenic embolic stroke and those with acute cardioembolic stroke. METHODS AND RESULTS: This study included 40 consecutive patients with acute aortogenic embolic stroke, and 40 age- and sex-matched patients with acute cardioembolic stroke. The diagnosis of aortogenic embolic stroke was made when patients met 5 criteria: (1)acute neurologic event lasting >24h; (2) positive signals on DWI; (3) atherosclerotic lesions ≥3.5-mm thick at the aortic arch on transesophageal echocardiography; (4) neuroradiologic features suggesting embolic stroke, such as lesions involving the brain cortex or the re-opening phenomenon of previously occluded vessels on Magnetic Resonance Angiography (MRA); and (5) absence of other embolic sources, including heart disease and carotid stenosis. The number, site, and maximal diameter of the infarct lesions on DWI were compared between the aortogenic and cardiogenic groups. The aortogenic patients more frequently had ≥3 lesions (25.0% vs. 2.5%, P<0.01), lesions with a maximal diameter <30mm (77.5% vs. 20.0%, P< 0.001), and vertebrobasilar system lesions (55.0% vs. 10.0%, P< 0.001) than the cardiogenic patients. CONCLUSIONS: Acute aortogenic embolic stroke is characterized by multiple (≥3) and small lesions, and involvement of the vertebrobasilar system.

Retinol palmitate prevents ischemia-induced cell changes in hippocampal neurons through the Notch1 signaling pathway in mice.

Retinol palmitate, an analog of vitamin A, plays multiple roles in the nervous system, including neural differentiation, axon outgrowth, and neural patterning, and is also an antioxidative agent and thereby potential neuroprotectant for brain ischemia. The present study aimed at investigating the protective effects of retinol palmitate against ischemia-induced brain injury in a bilateral common carotid artery occlusion (BCCAO) model in mice. Ischemia induced by 20-min BCCAO resulted in significant neuronal morphological changes and reactive astrocyte proliferation in the hippocampus, particularly in the CA1 region, and these changes were accompanied by increased Notch1 expression. Intraperitoneal retinol palmitate administration before ischemia reduced ischemic neurons with Notch1 expression; the differences were statistically significant in both the 1.2mg/kg group and 12 mg/kg group. These results show that retinol palmitate prevents brain ischemia-induced neuronal injury with Notch1 expression and that Notch1 signaling could be involved in the neuroprotective mechanism. Retinol palmitate could be a treatment option for human brain infarction.