Asymmetric cortical high signal on diffusion weighted-MRI in a case of Creutzfeldt-Jakob disease

Hipersinal no cortex cerebral e/ou nos gânglios da base observado com a técnica de difusão da ressonância magnética (RM-DIF) tem sido descrito como bom marcador diagnóstico da doença de Creutzfeldt-Jakob esporádica (DCJe). Relatamos caso de DCJe com evolução clínica atípica e achados incomuns na RM-DIF. Homem de 53 anos foi examinado com história de dois anos de demência rapidamente progressiva e ataxia cerebelar. Exame do líquido cefalorraqueano, incluindo pesquisa da proteína 14-3-3, foi normal; EEG não revelou atividade periódica; RM-DIF mostrou hiperintensidade nos giros que afetava quase inteiramente o manto cortical do hemisfério cerebral esquerdo e que no hemisfério direito se limitava à parte posterior do giro cíngulo. Análise do DNA revelou ausência de mutação ou de inserção no gene da proteína priônica e a presença de homozigose para metionina no códon 129. Biópsia cerebral confirmou o diagnóstico de DCJ. Hipersinal na RM-DIF pode ser limitado ao córtex cerebral e pode distribuir-se de modo muito assimétrico na DCJe.

Diffusion-weighted MR imaging of cystic lesions of neurocysticercosis: a preliminary study

Neurocysticercosis is an endemic disease in some developing countries. It has pleomorfic clinical and imaging findings, which are variable from patient to patient. In this preliminary note, we studied the magnetic resonance (MR) diffusion-weighted images (DWI) of sixteen patients presenting with cystic lesions of this disease diagnosed by clinical and laboratorial findings. All the lesions had hypointense signal and the similar apparent diffusion coeficient (ADC) values as the cerebrospinal fluid (CSF)

Brain spect in dementia: a clinical-scintigraphic correlation

The aim of this study was to compare the accuracy of computed tomography (CT) and single photon emission computerized tomography (SPECT) in the diagnosis of dementia. Fifty-two patients with clinical diagnosis of dementia and 11 controls were studied. The scans were interpreted by one experienced neuroradiologist and one nuclear radiologist, both blinded to the clinical data. In the diagnosis of dementia, CT and SPECT showed equal sensitivity (82.7 per cent) and statistically similar specificity (63.8 and 81.8 per cent, respectively). The specificity of SPECT in diagnosing Alzheimer's disease (100 per cent) was statistically superior to CT (69 per cent). However, both methods showed similar sensitivity in detecting Alzheimer's disease. In conclusion, SPECT and CT showed similar accuracy in the diagnosis of dementia. The quite high specificity of SPECT in Alzheimer's disease may be useful for confirming that diagnosis, particularly for patients with presenile onset of the disease.