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Assessment of Functional Characteristics of Amnestic Mild Cognitive Impairment and Alzheimer's Disease Using Various Methods of Resting-State FMRI Analysis.

Cha J, Hwang JM, Jo HJ, Seo SW, Na DL, Lee JM - Biomed Res Int (2015)

Bottom Line: The purpose of our study was to investigate the functional differences in aMCI and AD patients compared with healthy subjects in a meta-analysis.Nevertheless, patients with aMCI and AD displayed consistently decreased functional characteristics with all approaches.All approaches showed that the functional characteristics in the left parahippocampal gyrus were decreased in AD patients compared with healthy subjects.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, Hanyang University, Seoul 133-791, Republic of Korea.

ABSTRACT
Resting-state functional magnetic resonance imaging (RS FMRI) has been widely used to analyze functional alterations in amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) patients. Although many clinical studies of aMCI and AD patients using RS FMRI have been undertaken, conducting a meta-analysis has not been easy because of seed selection bias by the investigators. The purpose of our study was to investigate the functional differences in aMCI and AD patients compared with healthy subjects in a meta-analysis. Thus, a multimethod approach using regional homogeneity, amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), and global brain connectivity was used to investigate differences between three groups based on previously published data. According to the choice of RS FMRI approach used, the patterns of functional alteration were slightly different. Nevertheless, patients with aMCI and AD displayed consistently decreased functional characteristics with all approaches. All approaches showed that the functional characteristics in the left parahippocampal gyrus were decreased in AD patients compared with healthy subjects. Although some regions were slightly different according to the different RS FMRI approaches, patients with aMCI and AD showed a consistent pattern of decreased functional characteristics with all approaches.

No MeSH data available.


Related in: MedlinePlus

Brain regions exhibiting significant differences in the regional homogeneity (ReHo) index. (a) Brain regions showed significant differences in ReHo between healthy subjects and patients with aMCI and patients with AD (Pα < 0.05 (uncorrected P < 0.01, F > 4.78, 864 mm3, and AlphaSim corrected)). The results of the post hoc two-sample t-tests between pairs of the healthy subjects and patients with AD and patients with aMCI were as follows: significant differences in brain regions were found (b) in patients with aMCI compared with healthy subjects, (c) in patients with AD compared with patients with aMCI, and (d) in patients with AD compared with healthy subjects (Pα < 0.05). The images are oriented with the anterior side placed at the top and the left side placed to the right.
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fig2: Brain regions exhibiting significant differences in the regional homogeneity (ReHo) index. (a) Brain regions showed significant differences in ReHo between healthy subjects and patients with aMCI and patients with AD (Pα < 0.05 (uncorrected P < 0.01, F > 4.78, 864 mm3, and AlphaSim corrected)). The results of the post hoc two-sample t-tests between pairs of the healthy subjects and patients with AD and patients with aMCI were as follows: significant differences in brain regions were found (b) in patients with aMCI compared with healthy subjects, (c) in patients with AD compared with patients with aMCI, and (d) in patients with AD compared with healthy subjects (Pα < 0.05). The images are oriented with the anterior side placed at the top and the left side placed to the right.

Mentions: The results of the ANCOVA using age, sex, and education as covariates showed significant differences between the patients with aMCI and AD and healthy subjects (see Figures 2(a), 3(a), 4(a), and 5(a) and Tables 2–5 for details). Then, as shown in Figures 2(b)–2(d), 3(b)–3(d), 4(b)–4(d), and 5(b)–5(d) and Tables 6, 7, 8, and 9, we performed post hoc two-sample t-tests between pairs of groups. The ReHo, ALFF, fALFF, and GBC approaches showed that regions of the brain had decreased indices in patients with aMCI and AD compared with the healthy subjects. In particular, all RS FMRI approaches showed that the functional characteristics in the left parahippocampal gyrus were decreased in AD patients compared with healthy subjects. Therewith, significant group differences of the ReHo index were found in the middle temporal gyrus, ACC, postcentral gyrus, insula, precuneus, middle occipital gyrus, inferior parietal lobule, PCC, cingulate gyrus, and inferior frontal gyrus (Pα < 0.05; AlphaSim corrected, uncorrected P < 0.01 at a cluster size of at least 108 voxels; see Figure 2(a) and Table 2 for a detailed list of the regions). And significant group differences in the ALFF were found in superior temporal gyrus, medial frontal gyrus, parahippocampal gyrus, insula, superior frontal gyrus, caudate, and superior temporal gyrus (see Figure 3(a) and Table 3 for a detailed list of the regions). On the other hand, significant group differences in the fALFF were found in inferior parietal lobule, PCC, fusiform gyrus, middle frontal gyrus, precuneus, precentral gyrus, inferior frontal gyrus, middle temporal gyrus, parahippocampal gyrus, and cuneus (see Figure 4(a) and Table 4 for a detailed list of the regions). Significant group differences in the GBC index were found in the ACC, superior temporal gyrus, postcentral gyrus, parahippocampal gyrus, and cingulate gyrus (see Figure 5(a) and Table 5 for a detailed list of the regions).


Assessment of Functional Characteristics of Amnestic Mild Cognitive Impairment and Alzheimer's Disease Using Various Methods of Resting-State FMRI Analysis.

Cha J, Hwang JM, Jo HJ, Seo SW, Na DL, Lee JM - Biomed Res Int (2015)

Brain regions exhibiting significant differences in the regional homogeneity (ReHo) index. (a) Brain regions showed significant differences in ReHo between healthy subjects and patients with aMCI and patients with AD (Pα < 0.05 (uncorrected P < 0.01, F > 4.78, 864 mm3, and AlphaSim corrected)). The results of the post hoc two-sample t-tests between pairs of the healthy subjects and patients with AD and patients with aMCI were as follows: significant differences in brain regions were found (b) in patients with aMCI compared with healthy subjects, (c) in patients with AD compared with patients with aMCI, and (d) in patients with AD compared with healthy subjects (Pα < 0.05). The images are oriented with the anterior side placed at the top and the left side placed to the right.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4477185&req=5

fig2: Brain regions exhibiting significant differences in the regional homogeneity (ReHo) index. (a) Brain regions showed significant differences in ReHo between healthy subjects and patients with aMCI and patients with AD (Pα < 0.05 (uncorrected P < 0.01, F > 4.78, 864 mm3, and AlphaSim corrected)). The results of the post hoc two-sample t-tests between pairs of the healthy subjects and patients with AD and patients with aMCI were as follows: significant differences in brain regions were found (b) in patients with aMCI compared with healthy subjects, (c) in patients with AD compared with patients with aMCI, and (d) in patients with AD compared with healthy subjects (Pα < 0.05). The images are oriented with the anterior side placed at the top and the left side placed to the right.
Mentions: The results of the ANCOVA using age, sex, and education as covariates showed significant differences between the patients with aMCI and AD and healthy subjects (see Figures 2(a), 3(a), 4(a), and 5(a) and Tables 2–5 for details). Then, as shown in Figures 2(b)–2(d), 3(b)–3(d), 4(b)–4(d), and 5(b)–5(d) and Tables 6, 7, 8, and 9, we performed post hoc two-sample t-tests between pairs of groups. The ReHo, ALFF, fALFF, and GBC approaches showed that regions of the brain had decreased indices in patients with aMCI and AD compared with the healthy subjects. In particular, all RS FMRI approaches showed that the functional characteristics in the left parahippocampal gyrus were decreased in AD patients compared with healthy subjects. Therewith, significant group differences of the ReHo index were found in the middle temporal gyrus, ACC, postcentral gyrus, insula, precuneus, middle occipital gyrus, inferior parietal lobule, PCC, cingulate gyrus, and inferior frontal gyrus (Pα < 0.05; AlphaSim corrected, uncorrected P < 0.01 at a cluster size of at least 108 voxels; see Figure 2(a) and Table 2 for a detailed list of the regions). And significant group differences in the ALFF were found in superior temporal gyrus, medial frontal gyrus, parahippocampal gyrus, insula, superior frontal gyrus, caudate, and superior temporal gyrus (see Figure 3(a) and Table 3 for a detailed list of the regions). On the other hand, significant group differences in the fALFF were found in inferior parietal lobule, PCC, fusiform gyrus, middle frontal gyrus, precuneus, precentral gyrus, inferior frontal gyrus, middle temporal gyrus, parahippocampal gyrus, and cuneus (see Figure 4(a) and Table 4 for a detailed list of the regions). Significant group differences in the GBC index were found in the ACC, superior temporal gyrus, postcentral gyrus, parahippocampal gyrus, and cingulate gyrus (see Figure 5(a) and Table 5 for a detailed list of the regions).

Bottom Line: The purpose of our study was to investigate the functional differences in aMCI and AD patients compared with healthy subjects in a meta-analysis.Nevertheless, patients with aMCI and AD displayed consistently decreased functional characteristics with all approaches.All approaches showed that the functional characteristics in the left parahippocampal gyrus were decreased in AD patients compared with healthy subjects.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering, Hanyang University, Seoul 133-791, Republic of Korea.

ABSTRACT
Resting-state functional magnetic resonance imaging (RS FMRI) has been widely used to analyze functional alterations in amnestic mild cognitive impairment (aMCI) and Alzheimer's disease (AD) patients. Although many clinical studies of aMCI and AD patients using RS FMRI have been undertaken, conducting a meta-analysis has not been easy because of seed selection bias by the investigators. The purpose of our study was to investigate the functional differences in aMCI and AD patients compared with healthy subjects in a meta-analysis. Thus, a multimethod approach using regional homogeneity, amplitude of low-frequency fluctuation (ALFF), fractional ALFF (fALFF), and global brain connectivity was used to investigate differences between three groups based on previously published data. According to the choice of RS FMRI approach used, the patterns of functional alteration were slightly different. Nevertheless, patients with aMCI and AD displayed consistently decreased functional characteristics with all approaches. All approaches showed that the functional characteristics in the left parahippocampal gyrus were decreased in AD patients compared with healthy subjects. Although some regions were slightly different according to the different RS FMRI approaches, patients with aMCI and AD showed a consistent pattern of decreased functional characteristics with all approaches.

No MeSH data available.


Related in: MedlinePlus