RESUMO
The authors describe a magnetic resonance (MR) imaging technique to quantify the severity and distribution of cerebral atrophy by using automated volumetric analysis of the distribution of cerebrospinal fluid. The MR imaging technique demonstrated high diagnostic sensitivity and specificity in a group of healthy subjects and patients with dementing diseases. The authors conclude that this approach provides valuable clinical information that is complementary to information acquired with standard diagnostic practices.
Assuntos
Demência/líquido cefalorraquidiano , Demência/diagnóstico , Imageamento por Ressonância Magnética/métodos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico , Atrofia , Encéfalo/patologia , Demência Vascular/líquido cefalorraquidiano , Demência Vascular/diagnóstico , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: The occurrence of high signal abnormalities on T2 weighted images is strongly age related. The diagnostic value of these changes in a younger population with dementia is not currently known. We studied the potential of high signal changes on magnetic resonance imaging (MRI) in differentiating Alzheimer's disease (AD), frontotemporal dementia (FTD) and vascular dementia (VaD) in younger patients. METHODS: High signal abnormalities were rated, using a previously validated scale, from hard copies of T2 weighted axial images of 102 patients with AD (n=49), VaD (n=31), FTD (n=22) (mean ages 63-65 years). RESULTS: High signal abnormalities were widespread across AD, VaD and FTD. Although they were most frequent and most severe in the VaD group only lacunes and grade III deep white matter hyperintensities (DWMH) were specific for these patients. CONCLUSIONS: High signal changes on T2 weighted images on MRI are common across degenerative (AD and FTD) and vascular dementias. Although lacunes and grade III DWMH are specific for VaD, the low sensitivities (sensitivities: for lacunes, 0.32; for grade III DWMH, 0.16) limit their use as diagnostic markers for VaD. High signal changes on MRI should be interpreted with caution in dementias. Their presence, even in younger patients, should not deter one from diagnosing AD or FTD.
