Article

An MRI-based semiquantitative index for the evaluation of brain atrophy and lesions in Alzheimer's disease, mild cognitive impairment and normal aging.

National Research Council Canada, Institute for Biodiagnostics (Atlantic), Halifax, N.S., Canada.
Dementia and Geriatric Cognitive Disorders (Impact Factor: 2.81). 09/2010; 30(2):121-30. DOI: 10.1159/000319537
Source: PubMed

ABSTRACT This study investigates how T(1)-weighted MRI can be used to evaluate brain anatomical changes. We investigated these changes in Alzheimer's disease (AD) and normal aging.
A semiquantitative brain atrophy and lesion index (BALI) was constructed by adapting existing visual rating scales and validated in 3 datasets.
The T(1)- and T(2)-weighted-imaging-based scores were highly correlated. They were both closely associated with age and with cognitive test scores.
The T(1)-based BALI helps describe brain structural variability in AD, mild cognitive impairment and normal aging.

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    • "Although many studies that have used individual visual rating scales have been published in the past, few studies have created a CVRS that comprises the overall characteristics of brain lesions. Chen et al. have revealed that their T1-weighted-based brain lesion score correlates with age and MMSE [13]. However, their scale did not include hippocampal atrophy, which might be used to discriminate normal subjects from those with AD dementia [36], and the subscales have not been validated before. "
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    ABSTRACT: Background: Brain magnetic resonance imaging (MRI) shows cerebral structural changes. However, a unified comprehensive visual rating scale (CVRS) has seldom been studied. Thus, we combined brain atrophy and small vessel disease scales and used an MRI template as a CVRS. Objective: The aims of this study were to design a simple and reliable CVRS, validate it by investigating cerebral structural changes in clinical groups, and made comparison to the volumetric measurements. Methods: Elderly subjects (n = 260) with normal cognition (NC, n = 65), mild cognitive impairment (MCI, n = 101), or Alzheimer's disease (AD, n = 94) were evaluated with brain MRI according to the CVRS of brain atrophy and small vessel disease. Validation of the CVRS with structural changes, neuropsychological tests, and volumetric analyses was performed. Results: The CVRS revealed a high intra-rater and inter-rater agreement and it reflected the structural changes of subjects with NC, MCI, and AD better than volumetric measures (CVRS-coronal: F = 13.5, p < 0.001; CVRS-axial: F = 19.9, p < 0.001). The area under the receiver operation curve (aROC) of the CVRS showed higher accuracy than volumetric analyses. (NC versus MCI aROC: CVRS-coronal, 0.777; CVRS-axial, 0.773; MCI versus AD aROC: CVRS-coronal, 0.680; CVRS-axial, 0.681). Conclusion: The CVRS can be used clinically to conveniently measure structural changes of brain. It reflected cerebral structural changes of clinical groups and correlated with the age better than volumetric measures.
    Journal of Alzheimer's disease: JAD 11/2014; DOI:10.3233/JAD-142088 · 4.15 Impact Factor
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    • "Although many studies that have used individual visual rating scales have been published in the past, few studies have created a CVRS that comprises the overall characteristics of brain lesions. Chen et al. have revealed that their T1-weighted-based brain lesion score correlates with age and MMSE [13]. However, their scale did not include hippocampal atrophy, which might be used to discriminate normal subjects from those with AD dementia [36], and the subscales have not been validated before. "
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