Korean J Radiol.  2016 Dec;17(6):827-845. 10.3348/kjr.2016.17.6.827.

Structural MR Imaging in the Diagnosis of Alzheimer's Disease and Other Neurodegenerative Dementia: Current Imaging Approach and Future Perspectives

• Park M
• Moon WJ

• KMID: 2466280
• DOI: http://doi.org/10.3348/kjr.2016.17.6.827

Abstract

With the rise of aging population, clinical concern and research attention has shifted towards neuroimaging of dementia. The advent of 3T, magnetic resonance imaging (MRI) has permitted the anatomical imaging of neurodegenerative disease, specifically dementia, with improved resolution. Furthermore, more powerful techniques such as diffusion tensor imaging, quantitative susceptibility mapping, and magnetic transfer imaging have successfully emerged for the detection of micro-structural abnormalities. In the present review article, we provide a brief overview of Alzheimer's disease and explore recent neuroimaging developments in the field of dementia with an emphasis on structural MR imaging in order to propose a simple and easily applicable systematic approach to the imaging diagnosis of dementia.

Keyword

Dementia; Alzheimer's disease; Quantitative imaging; Magnetic resonance imaging; Diagnosis

MeSH Terms

Alzheimer Disease/*diagnosis/diagnostic imaging
Atrophy/diagnosis/diagnostic imaging
Brain/diagnostic imaging/pathology
Dementia/*diagnosis/diagnostic imaging
Diffusion Tensor Imaging
*Magnetic Resonance Imaging
Neuroimaging
White Matter/diagnostic imaging/pathology

Figure

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  Fig. 1 Proposed model of Alzheimer's disease pathogenesis adapted from Jack et al. Lancet Neurol 2010;9:119-128, with permission of Elsevier (8). Aβ = β-amyloid, MCI = mild cognitive impairment, MR = magnetic resonance

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  Fig. 2 Medial temporal lobe atrophy according to Scheltens et al. J Neurol 1995;242:557-560, with permission of Springer-Verlag 1995 (32).

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  Fig. 3 Posterior cortical atrophy as variant of Alzheimer's dementia. Note prominent atrophy of bilateral parietal lobe on sagittal (A) and axial (B) planes.

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  Fig. 4 Frontotemporal lobar atrophy of behavioral variant frontotemporal dementia.

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  Fig. 5 Bilateral prominent anterior temporal lobar atrophy of semantic variant frontotemporal dementia.

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  Fig. 6 Bilateral asymmetric perisylvian atrophy of primary non fluent aphasia variant frontotemporal dementia.

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  Fig. 7 Asymmetric atrophy of frontoparietal cortex (A) and basal ganglia (B) in corticobasal degeneration.

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  Fig. 8 Classification of white matter hyperintensity according to Fazekas et al. AJR Am J Roentgenol 1987;149:351-356, with permission of ARRS (62).

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  Fig. 9 Cerebral microbleeds exhibiting differential distribution pattern of hypertensive microangiopathy (A) and cerebral amyloid angiopathy (B).

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  Fig. 10 Exemplary cases of other uncommon dementias for differential diagnosis of cognitive impaired subjects using structural imaging. Progressive supranuclear palsy (A) shows typical midbrain atrophy. Normal pressure hydrocephalus (B) shows disproportionate ventricular enlargement to brain atrophy. Creutzfeldt-Jacob disease (C) shows typical cortical hyperintensities on DWI. DWI = diffusion weighted imaging

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  Fig. 11 Algorithm for differential diagnosis of cognitive impaired subjects by employing structural imaging. AD = Alzheimer's disease, BG = basal ganglia, CAA = cerebral amyloid angiopathy, CBD = corticobasal degeneration, CJD = Creutzfeldt–Jakob disease, DLB = dementia with Lewy bodies, DWI = diffusion weighted imaging, FTD = frontotemporal dementia, FTLD = frontotemporal lobar atrophy, MRI = magnetic resonance imaging, MTL = medial temporal lobe, NPH = normal pressure hydrocephalus, PCA = posterior cortical atrophy, PNFA = progressive nonfluent aphasia, PSP = progressive supranuclear palsy, SD = semantic dementia, VD = vascular dementia

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  Fig. 12 Quantitative susceptibility weighted imaging of healthy control (A), age-matched healthy control (B), Alzheimer's disease patient (C), and vascular dementia patient (D). Increased iron accumulation of caudate and putamen is noted in patients with Alzheimer's disease and vascular dementia as compared with normal subjects.

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