Hypoxic, Toxic, and Acquired Metabolic Encephalopathies at the Emergency Room: The Role of Magnetic Resonance Imaging.

Our purpose is to describe typical computed tomography and magnetic resonance imaging findings in encephalopathies in the emergency. The focus of this article are the most frequent toxic and acquired metabolic diseases and their preferential sites of involvement, such as hepatic encephalopathy, hypoglicemia, nonketotic hyperglycemia, osmotic demyelination, posterior reversible encephalopathy syndrome, uremia, illegal drug abuse, carbon monoxide poisoning, and hypoxic-ischemic encephalopathy. The radiologist must be able to identify the most usual patterns of lesion in computed tomography and magnetic resonance imaging in these settings.

Brain MRI abnormalities in Brazilian patients with neuromyelitis optica.

Brain abnormalities in neuromyelitis optica (NMO) have been reported previously, but the pathophysiological mechanism and clinical relevance of these abnormalities are poorly understood. We assessed the prevalence and patterns of brain MRI abnormalities in a Brazilian cohort of patients with NMO. Conventional brain MRI and medical records from 24 Brazilian patients with NMO were retrospectively evaluated. Brain MRI were classified into four subgroups: normal, non-specific lesions, multiple sclerosis (MS)-like lesions, and typical lesions. Brain lesions were detected in 19 patients (79.2%). Fourteen patients (58.3%) had non-specific lesions, three (12.5%) had MS-like lesions, and two (8.3%) had typical lesions. Differences between these subgroups with respect to the Expanded Disability Status Scale (EDSS) scores (p=0.86) were not significant. This study demonstrates a high prevalence of brain abnormalities in Brazilian patients with NMO; however, we did not find a significant relationship between these abnormalities and EDSS scores.