Can Neuroimaging Techniques Identify Individuals at Risk of Developing Alzheimer's Disease?

1997 ◽  
Vol 9 (4) ◽  
pp. 389-403 ◽  
Author(s):  
Cássio M. C. Bottino ◽  
Osvaldo P. Almeida
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
At Risk ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Ε4 Allele ◽  
Neuroimaging Techniques

Recent studies indicate that neuroimaging techniques such as magnetic resonance imaging, positron emission tomography, and single-photon emission computed tomography can accurately differentiate patients with Alzheimer's disease (AD) from elderly controls. This report reviews the results of neuroimaging studies of two at-risk populations: subjects with the ε4 allele of the apolipoprotein E and those with mild cognitive impairment. The results of the work published to date indicate that the presence of the ε4 allele is a risk factor for AD and that its predictive validity can be enhanced by neuropsychological and/or neuroimaging evaluation. The results also show that patients with mild cognitive impairment display a number of structural and functional imaging abnormalities that are more pronounced in the temporal and parietal lobes. We suggest that the use of neuroimaging techniques can improve the detection of subjects early in the course of AD, although the sensitivity and the specificity of this approach still await a more detailed prospective evaluation.

scholarly journals Neuroimaging techniques for diagnosing Alzheimer’s disease and cerebrovascular diseases with cognitive impairment

2019 ◽  
Vol 11 (3S) ◽  
pp. 18-25 ◽  
Author(s):  
I. V. Litvinenko ◽  
A. Yu. Emelin ◽  
V. Yu. Lobzin ◽  
K. A. Kolmakova
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Magnetic Resonance ◽  
Rating Scales ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Resonance Spectroscopy ◽  
Neuroimaging Techniques

The paper provides data on current neuroimaging techniques for diagnosing Alzheimer’s disease and vascular cognitive impairment (CN). Structural neuroimaging methods can identify potentially treatable diseases leading to dementia and assess the magnitude and localization of atrophic and cerebrovascular changes in brain tissue. Particular attention is paid to the specific signs of Alzheimer’s disease: to the visual assessment of sections and the use of various rating scales (GCA, MTA, Koedam). Vascular changes that are most significant for the development of CI are considered. A new approach to diagnosing CI is presented, by taking into account the biomarkers of amyloidosis, tauopathy, neurodegeneration, and cerebrovascular damage. The results of the authors’ own investigations using positron emission tomography, single photon emission computed tomography, magnetic resonance spectroscopy, and functional magnetic resonance imaging at rest allow these techniques to be recommended for the early diagnosis of CI of different genesis.

scholarly journals Effect of Toki-Shakuyaku-San on Regional Cerebral Blood Flow in Patients with Mild Cognitive Impairment and Alzheimer's Disease

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Teruyuki Matsuoka ◽  
Jin Narumoto ◽  
Keisuke Shibata ◽  
Aiko Okamura ◽  
Shogo Taniguchi ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Regional Cerebral Blood Flow ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Regional Cerebral Blood

The aim of this study was to examine the effect of toki-shakuyaku-san (TSS) on mild cognitive impairment (MCI) and Alzheimer's disease (AD) using single-photon emission computed tomography (SPECT). All subjects were administered TSS (7.5 g/day) for eight weeks. SPECT and evaluations using the Mini Mental State Examination (MMSE), Neuropsychiatric Inventory, and Physical Self-Maintenance Scale were performed before and after treatment with TSS. Three patients with MCI and five patients with AD completed the study. No adverse events occurred during the study period. After treatment with TSS, regional cerebral blood flow (rCBF) in the posterior cingulate was significantly higher than that before treatment. No brain region showed a significant decrease in rCBF. TSS treatment also tended to improve the score for orientation to place on the MMSE. These results suggest that TSS could be useful for treatment of MCI and AD.

The Role of Apolipoprotein E ε4 in Early and Late Mild Cognitive Impairment

2021 ◽  
Vol 84 (6) ◽  
pp. 472-480
Author(s):  
Yulin Luo ◽  
Li Tan ◽  
Joseph Therriault ◽  
Hua Zhang ◽  
Ying Gao ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Apolipoprotein E ◽  
Amyloid Β ◽  
Disease Assessment ◽  
Tau Pathology ◽  
Ε4 Allele ◽  
State Examination

<b><i>Background:</i></b> Apolipoprotein E (<i>APOE</i>) ε4 is highly associated with mild cognitive impairment (MCI). However, the specific influence of <i>APOE</i> ε4 status on tau pathology and cognitive decline in early MCI (EMCI) and late MCI (LMCI) is poorly understood. Our goal was to evaluate the association of <i>APOE</i> ε4 with cerebrospinal fluid (CSF) tau levels and cognition in EMCI and LMCI patients in the Alzheimer’s Disease Neuroimaging Initiative database, and whether this association was mediated by amyloid-β (Aβ). <b><i>Methods:</i></b> Participants were 269 cognitively normal (CN), 262 EMCI, and 344 LMCI patients. They underwent CSF Aβ42 and tau detection, <i>APOE</i> ε4 genotyping, Mini-Mental State Examination, (MMSE), and Alzheimer’s disease assessment scale (ADAS)-cog assessments. Linear regressions were used to examine the relation of <i>APOE</i> ε4 and CSF tau levels and cognitive scores in persons with and without Aβ deposition (Aβ+ and Aβ−). <b><i>Results:</i></b> The prevalence of <i>APOE</i> ε4 is higher in EMCI and LMCI than in CN (<i>p</i> &#x3c; 0.001 for both), and in LMCI than in EMCI (<i>p</i> = 0.001). <i>APOE</i> ε4 allele was significantly higher in Aβ+ subjects than in Aβ− subjects (<i>p</i> &#x3c; 0.001). Subjects who had a lower CSF Aβ42 level and were <i>APOE</i> ε4-positive experienced higher levels of CSF tau and cognitive scores in EMCI and/or LMCI. <b><i>Conclusions:</i></b> An <i>APOE</i> ε4 allele is associated with increased CSF tau and worse cognition in both EMCI and LMCI, and this association may be mediated by Aβ. We conclude that <i>APOE</i> ε4 may be an important mediator of tau pathology and cognition in the early stages of AD.

Discrepancy Between the Degree of Cognitive Impairment and Brain Imaging Abnormalities in Alzheimer’s Disease Patients Is Associated with Cognitive Reserve

2021 ◽  
pp. 1-9
Author(s):  
Tomohiko Sato ◽  
Haruo Hanyu ◽  
Yumi Koyama ◽  
Haruka Horita ◽  
Toshinori Aoki ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Impairment ◽  
Brain Imaging ◽  
Cognitive Reserve ◽  
Photon Emission ◽  
Clinical Manifestations ◽  
Leisure Activity ◽  
Emission Computed Tomography ◽  
Imaging Findings

Background: In Alzheimer’s disease (AD) patients, the severity of cognitive impairment is thought to correlate with the degree of brain imaging abnormalities. However, some patients show only mild cognitive deficit, despite severe brain atrophy on magnetic resonance imaging (MRI) or marked hypoperfusion in the cerebral cortices on single-photon emission computed tomography (SPECT). This suggests that cognitive reserve (CR) can compensate for the clinical manifestations of AD in patients with extensive brain pathology. Objective: We aimed to determine whether this discrepancy between cognitive and imaging findings is associated with CR. Methods: Factors associated with the discrepancy between the degree of cognitive impairment and MRI (medial temporal lobe atrophy) and SPECT (posterior cerebral hypoperfusion) findings were analyzed in 135 patients with probable AD. Factors as proxies for CR included education, occupation, leisure activity, comorbidities, frailty, and other demographics. The discrepancy index (DI) was calculated as the difference between the degree of imaging abnormalities and the degree of cognitive dysfunction. Results: Multiple regression analysis showed that leisure activity and education were significantly associated with the discrepancy between cognitive and imaging findings. When the level of CR was determined based on leisure activity and education, the high-CR group showed a significantly larger DI than the moderate- and low-CR groups. Conclusion: The discrepancy between cognitive and imaging findings in patients with AD is associated with CR, measured using a combination of two indicators, i.e., leisure activity and education. Therefore, lifestyle interventions may delay the appearance of clinical symptoms resulting from underlying AD pathology, by increasing CR.

scholarly journals Efficacy and Limitations of rCBF-SPECT in the Diagnosis of Alzheimer’s Disease With Amyloid-PET

2019 ◽  
Vol 34 (5) ◽  
pp. 314-321
Author(s):  
Miwako Takahashi ◽  
Tomoko Tada ◽  
Tomomi Nakamura ◽  
Keitaro Koyama ◽  
Toshimitsu Momose
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Rating Scale ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Amyloid Pet ◽  
Clinical Dementia Rating ◽  
Positron Emission ◽  
Rcbf Spect

This study aimed to assess efficacy and limitations of regional cerebral blood flow imaging using single-photon emission computed tomography (rCBF-SPECT) in the diagnosis of Alzheimer’s disease (AD) with amyloid-positron emission tomography (amyloid-PET). Thirteen patients, who underwent both rCBF-SPECT and amyloid-PET after clinical diagnosis of AD or mild cognitive impairment, were retrospectively identified. The rCBF-SPECTs were classified into 4 grades, from typical AD pattern to no AD pattern of hypoperfusion; amyloid-beta (Aβ) positivity was assessed by amyloid-PET. Four patients were categorized into a typical AD pattern on rCBF-SPECT, and all were Aβ+. The other 9 patients did not exhibit a typical AD pattern; however, 4 were Aβ+. The Mini-Mental State Examination score and Clinical Dementia Rating scale were not significantly different between Aβ+ and Aβ– patients. A typical AD pattern on rCBF-SPECT can reflect Aβ+; however, if not, rCBF-SPECT has a limitation to predict amyloid pathology.

scholarly journals The Use of [99mTc]-HM-PAO in the Diagnosis of Primary Degenerative Dementia

1988 ◽  
Vol 8 (1_suppl) ◽  
pp. S123-S126 ◽  
Author(s):  
H. J. Testa ◽  
J. S. Snowden ◽  
D. Neary ◽  
R. A. Shields ◽  
A. W. I. Burjan ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Progressive Supranuclear Palsy ◽  
Frontal Lobe ◽  
Single Photon ◽  
Photon Emission ◽  
Cerebral Atrophy ◽  
Emission Computed Tomography ◽  
Clinical Value ◽  
Diagnosis Of Dementia

The clinical value of single photon emission computed tomography (SPECT) in the differential diagnosis of dementia due to cerebral atrophy was evaluated by comparing the pattern of distribution [99mTc]–HM-PAO in three dementing conditions. Imaging was carried out in 26 patients with suspected Alzheimer's disease, 14 with dementia of the frontal-lobe type, and 13 with progressive supranuclear palsy. Images were evaluated and reported without knowledge of clinical diagnosis with respect to regions of reduced uptake of tracer. Reduced uptake in the posterior cerebral hemispheres was characteristic of Alzheimer's disease, while selective anterior hemisphere abnormalities characterized both dementia of the frontal-lobe type and progressive supranuclear palsy. The latter conditions could be distinguished on the basis of the appearance of integrity of the rim of the frontal cortex. The technique has an important role in the differentiation of degenerative dementias.

scholarly journals Case Report: Usefulness of Biomarkers for Alzheimer's Disease in Two Cases With Very-Late-Onset Schizophrenia-Like Psychosis

2021 ◽  
Vol 12 ◽  
Author(s):  
Yuto Satake ◽  
Hideki Kanemoto ◽  
Kenji Yoshiyama ◽  
Ryoko Nakahama ◽  
Keiko Matsunaga ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Psychotic Disorders ◽  
Late Onset ◽  
Single Photon ◽  
Photon Emission ◽  
Brain Magnetic Resonance Imaging ◽  
Later Life ◽  
Emission Computed Tomography ◽  
Amyloid Pet

The association between primary psychotic disorders emerging in later life and neurodegenerative diseases, including Alzheimer's disease (AD), is controversial. We present two female non-demented cases of psychosis with onset above the age of 60 years. Cases 1 and 2 were aged was 68 and 81 years, respectively. They suffered from persecutory delusions and scored 28 on the Mini-Mental State Examination (MMSE) at the first examination. Although detailed neuropsychological tests detected amnesia, they had preserved daily life function. Brain magnetic resonance imaging, N-isopropyl-p-[123I] iodoamphetamine (123I-IMP) single-photon emission computed tomography, and cardiac [123I]-metaiodobenzylguanidine (123I-MIBG) scintigraphy showed no specific abnormalities in either case. We diagnosed them with very-late-onset schizophrenia-like psychosis (VLOSLP) because there was no evidence that their psychoses were derived from organic diseases or affective disorders. Upon close inspection, the AD biomarkers, cerebrospinal fluid (CSF) testing and Florbetapir F 18 positron emission tomography (PET), were positive in Case 1 and negative in Case 2. Case 1 scored 25 1 year later and 23 2 years later on the MMSE and was finally diagnosed as AD dementia. These two cases suggest that some clinically diagnosed VLOSLPs may be a prodromal AD. Although VLOSLP is a disease entity supposed to be a primary psychotic disorder, some are probably secondary psychosis with insidious neurodegeneration. Advanced biomarkers such as amyloid PET and CSF may contribute to the detection of secondary psychosis from clinically diagnosed VLOSLP.

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