Neuroimaging correlates of pathologically defined subtypes of Alzheimer's disease: A case-control study

Department of Radiology, Mayo Clinic, Rochester, MN, USA. Electronic address: .
The Lancet Neurology (Impact Factor: 21.9). 08/2012; 11(10):868-77. DOI: 10.1016/S1474-4422(12)70200-4
Source: PubMed


Three subtypes of Alzheimer's disease (AD) have been pathologically defined on the basis of the distribution of neurofibrillary tangles: typical AD, hippocampal-sparing AD, and limbic-predominant AD. Compared with typical AD, hippocampal-sparing AD has more neurofibrillary tangles in the cortex and fewer in the hippocampus, whereas the opposite pattern is seen in limbic-predominant AD. We aimed to determine whether MRI patterns of atrophy differ between these subtypes and whether structural neuroimaging could be a useful predictor of pathological subtype at autopsy.

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    • "Therefore, to extract accurate macrostructural brain signatures of age-related neuropathologies, it is necessary to combine MRI and pathology information on the same individual. A number of studies have used in vivo or ex vivo MRI and autopsy to examine the neuropathologic correlates of brain macrostructure (Barkhof et al., 2007; Burton et al., 2012; Dawe et al., 2011; Erten-Lyons et al., 2013a; Jagust et al., 2008; Josephs et al., 2008, 2013; Kantarci et al., 2012; Kaur et al., 2014; Raman et al., 2014; Rohrer et al., 2010; Toledo et al., 2013; Vemuri et al., 2011; Whitwell et al., 2008, 2011, 2012; Zarow et al., 2011). However, these MRI-pathology investigations were characterized by one or more of the following limitations: (1) relatively long intervals between in vivo MRI and autopsy, which may have allowed formation of additional pathology not captured in the MRI data; (2) relatively limited spatial detail, typically focusing on the volume of the whole brain, ventricles, hippocampus , or other medial temporal lobe structures; (3) use of clinical cohorts, limiting applicability of the findings to the general "
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