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Automated Classification to Predict the Progression of Alzheimer's Disease Using Whole-Brain Volumetry and DTI.

Jung WB, Lee YM, Kim YH, Mun CW - Psychiatry Investig (2015)

Bottom Line: Medial temporal regions in AD patients were dominantly detected with cortical thinning and volume atrophy compared with SMI and MCI patients.Damage to white matter integrity was also accredited with decreased fractional anisotropy and increased mean diffusivity (MD) across the three groups.This proposed method may be a potential tool to diagnose AD pathology with the current clinical criteria.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering/u-HARC, Inje University, Gimhae, Republic of Korea.

ABSTRACT

Objective: This study proposes an automated diagnostic method to classify patients with Alzheimer's disease (AD) of degenerative etiology using magnetic resonance imaging (MRI) markers.

Methods: Twenty-seven patients with subjective memory impairment (SMI), 18 patients with mild cognitive impairment (MCI), and 27 patients with AD participated. MRI protocols included three dimensional brain structural imaging and diffusion tensor imaging to assess the cortical thickness, subcortical volume and white matter integrity. Recursive feature elimination based on support vector machine (SVM) was conducted to determine the most relevant features for classifying abnormal regions and imaging parameters, and then a factor analysis for the top-ranked factors was performed. Subjects were classified using nonlinear SVM.

Results: Medial temporal regions in AD patients were dominantly detected with cortical thinning and volume atrophy compared with SMI and MCI patients. Damage to white matter integrity was also accredited with decreased fractional anisotropy and increased mean diffusivity (MD) across the three groups. The microscopic damage in the subcortical gray matter was reflected in increased MD. Classification accuracy between pairs of groups (SMI vs. MCI, MCI vs. AD, SMI vs. AD) and among all three groups were 84.4% (±13.8), 86.9% (±10.5), 96.3% (±4.6), and 70.5% (±11.5), respectively.

Conclusion: This proposed method may be a potential tool to diagnose AD pathology with the current clinical criteria.

No MeSH data available.


Related in: MedlinePlus

Significantly different structural volume (×10-3) normalized by intracranial volume in patients with SMI, MCI and AD. Indicators mean the significances from MANCOVA followed by Boferroni post-hoc test. *p<0.05 and †p<0.01 between SMI and AD, ‡p<0.05 between SMI and MCI, ∥p<0.05 between MCI and AD. SMI: subjective memory impairment, MCI: mild cognitive impairment, AD: Alzheimer's disease, HP: hippocampus, AMG: amygdale, NA: nucleus accumbens, LV: lateral ventricle, ILV: inferior lateral ventricle, R: right, L: left, Int: inter hemisphere.
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Figure 2: Significantly different structural volume (×10-3) normalized by intracranial volume in patients with SMI, MCI and AD. Indicators mean the significances from MANCOVA followed by Boferroni post-hoc test. *p<0.05 and †p<0.01 between SMI and AD, ‡p<0.05 between SMI and MCI, ∥p<0.05 between MCI and AD. SMI: subjective memory impairment, MCI: mild cognitive impairment, AD: Alzheimer's disease, HP: hippocampus, AMG: amygdale, NA: nucleus accumbens, LV: lateral ventricle, ILV: inferior lateral ventricle, R: right, L: left, Int: inter hemisphere.

Mentions: Seventeen GM structures showed the significant differences on the neurodegenerative states compared with the other groups. Cortical thinning was found in the medial temporal (i.e., bilateral entorhinal cortex and bilateral fusiform cortex) regions, bilateral temporal pole and left insula cortex in patients with AD compared with those in patients with SMI. Patients with MCI showed intermediate thickness in these cortices except the right temporal pole region (Figure 1). Volume atrophy occurred in the HP, amygdala (AMG) and nucleus accumbens (NA) in both hemispheres in AD patients compared with SMI. Atrophy between patients with MCI and AD was also observed in the left HP and AMG. Volumes of the right HP and AMG were significantly decreased in MCI patients compared to those with SMI. In contrast, ventricular volumes (i.e., lateral ventricles, third ventricles, and bilateral inferior lateral ventricles) were significantly enlarged in patients with AD compared with those of patients with SMI and MCI (Figure 2).


Automated Classification to Predict the Progression of Alzheimer's Disease Using Whole-Brain Volumetry and DTI.

Jung WB, Lee YM, Kim YH, Mun CW - Psychiatry Investig (2015)

Significantly different structural volume (×10-3) normalized by intracranial volume in patients with SMI, MCI and AD. Indicators mean the significances from MANCOVA followed by Boferroni post-hoc test. *p<0.05 and †p<0.01 between SMI and AD, ‡p<0.05 between SMI and MCI, ∥p<0.05 between MCI and AD. SMI: subjective memory impairment, MCI: mild cognitive impairment, AD: Alzheimer's disease, HP: hippocampus, AMG: amygdale, NA: nucleus accumbens, LV: lateral ventricle, ILV: inferior lateral ventricle, R: right, L: left, Int: inter hemisphere.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4310927&req=5

Figure 2: Significantly different structural volume (×10-3) normalized by intracranial volume in patients with SMI, MCI and AD. Indicators mean the significances from MANCOVA followed by Boferroni post-hoc test. *p<0.05 and †p<0.01 between SMI and AD, ‡p<0.05 between SMI and MCI, ∥p<0.05 between MCI and AD. SMI: subjective memory impairment, MCI: mild cognitive impairment, AD: Alzheimer's disease, HP: hippocampus, AMG: amygdale, NA: nucleus accumbens, LV: lateral ventricle, ILV: inferior lateral ventricle, R: right, L: left, Int: inter hemisphere.
Mentions: Seventeen GM structures showed the significant differences on the neurodegenerative states compared with the other groups. Cortical thinning was found in the medial temporal (i.e., bilateral entorhinal cortex and bilateral fusiform cortex) regions, bilateral temporal pole and left insula cortex in patients with AD compared with those in patients with SMI. Patients with MCI showed intermediate thickness in these cortices except the right temporal pole region (Figure 1). Volume atrophy occurred in the HP, amygdala (AMG) and nucleus accumbens (NA) in both hemispheres in AD patients compared with SMI. Atrophy between patients with MCI and AD was also observed in the left HP and AMG. Volumes of the right HP and AMG were significantly decreased in MCI patients compared to those with SMI. In contrast, ventricular volumes (i.e., lateral ventricles, third ventricles, and bilateral inferior lateral ventricles) were significantly enlarged in patients with AD compared with those of patients with SMI and MCI (Figure 2).

Bottom Line: Medial temporal regions in AD patients were dominantly detected with cortical thinning and volume atrophy compared with SMI and MCI patients.Damage to white matter integrity was also accredited with decreased fractional anisotropy and increased mean diffusivity (MD) across the three groups.This proposed method may be a potential tool to diagnose AD pathology with the current clinical criteria.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical Engineering/u-HARC, Inje University, Gimhae, Republic of Korea.

ABSTRACT

Objective: This study proposes an automated diagnostic method to classify patients with Alzheimer's disease (AD) of degenerative etiology using magnetic resonance imaging (MRI) markers.

Methods: Twenty-seven patients with subjective memory impairment (SMI), 18 patients with mild cognitive impairment (MCI), and 27 patients with AD participated. MRI protocols included three dimensional brain structural imaging and diffusion tensor imaging to assess the cortical thickness, subcortical volume and white matter integrity. Recursive feature elimination based on support vector machine (SVM) was conducted to determine the most relevant features for classifying abnormal regions and imaging parameters, and then a factor analysis for the top-ranked factors was performed. Subjects were classified using nonlinear SVM.

Results: Medial temporal regions in AD patients were dominantly detected with cortical thinning and volume atrophy compared with SMI and MCI patients. Damage to white matter integrity was also accredited with decreased fractional anisotropy and increased mean diffusivity (MD) across the three groups. The microscopic damage in the subcortical gray matter was reflected in increased MD. Classification accuracy between pairs of groups (SMI vs. MCI, MCI vs. AD, SMI vs. AD) and among all three groups were 84.4% (±13.8), 86.9% (±10.5), 96.3% (±4.6), and 70.5% (±11.5), respectively.

Conclusion: This proposed method may be a potential tool to diagnose AD pathology with the current clinical criteria.

No MeSH data available.


Related in: MedlinePlus