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Chouliaras L, O'Brien JT. The use of neuroimaging techniques in the early and differential diagnosis of dementia. Mol Psychiatry 2023; 28:4084-4097. [PMID: 37608222 PMCID: PMC10827668 DOI: 10.1038/s41380-023-02215-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/24/2023]
Abstract
Dementia is a leading cause of disability and death worldwide. At present there is no disease modifying treatment for any of the most common types of dementia such as Alzheimer's disease (AD), Vascular dementia, Lewy Body Dementia (LBD) and Frontotemporal dementia (FTD). Early and accurate diagnosis of dementia subtype is critical to improving clinical care and developing better treatments. Structural and molecular imaging has contributed to a better understanding of the pathophysiology of neurodegenerative dementias and is increasingly being adopted into clinical practice for early and accurate diagnosis. In this review we summarise the contribution imaging has made with particular focus on multimodal magnetic resonance imaging (MRI) and positron emission tomography imaging (PET). Structural MRI is widely used in clinical practice and can help exclude reversible causes of memory problems but has relatively low sensitivity for the early and differential diagnosis of dementia subtypes. 18F-fluorodeoxyglucose PET has high sensitivity and specificity for AD and FTD, while PET with ligands for amyloid and tau can improve the differential diagnosis of AD and non-AD dementias, including recognition at prodromal stages. Dopaminergic imaging can assist with the diagnosis of LBD. The lack of a validated tracer for α-synuclein or TAR DNA-binding protein 43 (TDP-43) imaging remain notable gaps, though work is ongoing. Emerging PET tracers such as 11C-UCB-J for synaptic imaging may be sensitive early markers but overall larger longitudinal multi-centre cross diagnostic imaging studies are needed.
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Affiliation(s)
- Leonidas Chouliaras
- Department of Psychiatry, University of Cambridge School of Clinical Medicine, Cambridge, UK
- Specialist Dementia and Frailty Service, Essex Partnership University NHS Foundation Trust, St Margaret's Hospital, Epping, UK
| | - John T O'Brien
- Department of Psychiatry, University of Cambridge School of Clinical Medicine, Cambridge, UK.
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK.
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Luo X, Hong H, Li K, Zeng Q, Wang S, Li Z, Fu Y, Liu X, Hong L, Li J, Zhang X, Zhong S, Jiaerken Y, Liu Z, Chen Y, Huang P, Zhang M. Distinct cerebral small vessel disease impairment in early- and late-onset Alzheimer's disease. Ann Clin Transl Neurol 2023; 10:1326-1337. [PMID: 37345812 PMCID: PMC10424647 DOI: 10.1002/acn3.51824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 05/10/2023] [Accepted: 05/26/2023] [Indexed: 06/23/2023] Open
Abstract
OBJECTIVE This study investigated cerebral small vessel disease (CSVD) damage patterns in early-onset and late-onset Alzheimer's disease (EOAD and LOAD) and their effects on cognitive function. METHODS This study included 93 participants, 45 AD patients (14 EOAD and 31 LOAD), and 48 normal controls (13 YNC and 35 ONC) from the ADNI database. All participants had diffusion tensor imaging data; some had amyloid PET and plasma p-tau181 data. The study used peak width of skeletonized mean diffusivity (PSMD) to measure CSVD severity and compared PSMD between patients and age-matched controls. The effect of age on the relationship between PSMD and cognition was also examined. The study also repeated the analysis in amyloid-positive AD patients and amyloid-negative controls in another independent database (31 EOAD and 38 LOAD), and the merged database. RESULTS EOAD and LOAD showed similar cognitive function and disease severity. PSMD was validated as a reliable correlate of cognitive function. In the ADNI database, PSMD was significantly higher for LOAD and showed a tendency to increase for EOAD; in the independent and merged databases, PSMD was significantly higher for both LOAD and EOAD. The impact of PSMD on cognitive function was notably greater in the younger group (YNC and EOAD) than in the older group (ONC and LOAD), as supported by the ADNI and merged databases. INTERPRETATION EOAD has less CSVD burden than LOAD, but has a greater impact on cognition. Proactive cerebrovascular prevention strategies may have potential clinical value for younger older adults with cognitive decline.
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Affiliation(s)
- Xiao Luo
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Hui Hong
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Kaicheng Li
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Qingze Zeng
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Shuyue Wang
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Zheyu Li
- Department of NeurologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Yanv Fu
- Department of NeurologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Xiaocao Liu
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Luwei Hong
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Jixuan Li
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Xinyi Zhang
- Department of NeurologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Siyan Zhong
- Department of NeurologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Yeerfan Jiaerken
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Zhirong Liu
- Department of NeurologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Yanxing Chen
- Department of NeurologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Peiyu Huang
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
| | - Minming Zhang
- Department of RadiologyThe Second Affiliated Hospital of Zhejiang University School of MedicineHangzhouChina
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Sharp FR, DeCarli CS, Jin LW, Zhan X. White matter injury, cholesterol dysmetabolism, and APP/Abeta dysmetabolism interact to produce Alzheimer's disease (AD) neuropathology: A hypothesis and review. Front Aging Neurosci 2023; 15:1096206. [PMID: 36845656 PMCID: PMC9950279 DOI: 10.3389/fnagi.2023.1096206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/30/2023] [Indexed: 02/12/2023] Open
Abstract
We postulate that myelin injury contributes to cholesterol release from myelin and cholesterol dysmetabolism which contributes to Abeta dysmetabolism, and combined with genetic and AD risk factors, leads to increased Abeta and amyloid plaques. Increased Abeta damages myelin to form a vicious injury cycle. Thus, white matter injury, cholesterol dysmetabolism and Abeta dysmetabolism interact to produce or worsen AD neuropathology. The amyloid cascade is the leading hypothesis for the cause of Alzheimer's disease (AD). The failure of clinical trials based on this hypothesis has raised other possibilities. Even with a possible new success (Lecanemab), it is not clear whether this is a cause or a result of the disease. With the discovery in 1993 that the apolipoprotein E type 4 allele (APOE4) was the major risk factor for sporadic, late-onset AD (LOAD), there has been increasing interest in cholesterol in AD since APOE is a major cholesterol transporter. Recent studies show that cholesterol metabolism is intricately involved with Abeta (Aβ)/amyloid transport and metabolism, with cholesterol down-regulating the Aβ LRP1 transporter and upregulating the Aβ RAGE receptor, both of which would increase brain Aβ. Moreover, manipulating cholesterol transport and metabolism in rodent AD models can ameliorate pathology and cognitive deficits, or worsen them depending upon the manipulation. Though white matter (WM) injury has been noted in AD brain since Alzheimer's initial observations, recent studies have shown abnormal white matter in every AD brain. Moreover, there is age-related WM injury in normal individuals that occurs earlier and is worse with the APOE4 genotype. Moreover, WM injury precedes formation of plaques and tangles in human Familial Alzheimer's disease (FAD) and precedes plaque formation in rodent AD models. Restoring WM in rodent AD models improves cognition without affecting AD pathology. Thus, we postulate that the amyloid cascade, cholesterol dysmetabolism and white matter injury interact to produce and/or worsen AD pathology. We further postulate that the primary initiating event could be related to any of the three, with age a major factor for WM injury, diet and APOE4 and other genes a factor for cholesterol dysmetabolism, and FAD and other genes for Abeta dysmetabolism.
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Affiliation(s)
| | - Charles S. DeCarli
- Department of Neurology, The MIND Institute, University of California at Davis Medical Center, Sacramento, CA, United States
| | - Lee-Way Jin
- Department of Neurology, The MIND Institute, University of California at Davis Medical Center, Sacramento, CA, United States
| | - Xinhua Zhan
- Department of Neurology, The MIND Institute, University of California at Davis Medical Center, Sacramento, CA, United States
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Hyperconnectivity matters in early-onset Alzheimer's disease: a resting-state EEG connectivity study. Neurophysiol Clin 2022; 52:459-471. [DOI: 10.1016/j.neucli.2022.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 11/11/2022] Open
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Luo X, Wang S, Jiaerken Y, Li K, Zeng Q, Zhang R, Wang C, Xu X, Wu D, Huang P, Zhang M. Distinct fiber-specific white matter reductions pattern in early- and late-onset Alzheimer's disease. Aging (Albany NY) 2021; 13:12410-12430. [PMID: 33930871 PMCID: PMC8148465 DOI: 10.18632/aging.202702] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 02/08/2021] [Indexed: 01/31/2023]
Abstract
Background: The underlying white matter impairment in patients with early and late-onset Alzheimer’s disease (EOAD and LOAD) is still unclear, and this might due to the complex AD pathology. Methods: We included 31 EOAD, 45 LOAD, and 64 younger, 46 elder controls in our study to undergo MRI examinations. Fiber density (FD) and fiber bundle cross-section (FC) were measured using fixel-based analysis based on diffusion weighted images. On whole brain and tract-based level, we compared these parameters among different groups (p<0.05, FWE corrected). Moreover, we verified our results in another independent dataset using the same analyses. Results: Compared to young healthy controls, EOAD had significantly lower FD in the splenium of corpus callosum, limbic tracts, cingulum bundles, and posterior thalamic radiation, and higher FC in the splenium of corpus callosum, dorsal cingulum and posterior thalamic radiation. On the other hand, LOAD had lower FD and FC as well. Importantly, a similar pattern was found in the independent validation dataset. Among all groups, both the FD and FC were associated with cognitive function. Furthermore, FD of fornix column and body, and FC of ventral cingulum were associated with composite amyloid and tau level (r=-0.34 and -0.53, p<0.001) respectively. Conclusions: EOAD and LOAD were characterized by distinct white matter impairment patterns, which may be attributable to their different neuropathologies.
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Affiliation(s)
- Xiao Luo
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Shuyue Wang
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Yeerfan Jiaerken
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Kaicheng Li
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Qingze Zeng
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Ruiting Zhang
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Chao Wang
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaopei Xu
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Dan Wu
- Key Laboratory for Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, China
| | - Peiyu Huang
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Minming Zhang
- Department of Radiology, The 2nd Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
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Meysami S, Raji CA, Merrill DA, Porter VR, Mendez MF. Quantitative MRI Differences Between Early versus Late Onset Alzheimer's Disease. Am J Alzheimers Dis Other Demen 2021; 36:15333175211055325. [PMID: 34814740 PMCID: PMC10623969 DOI: 10.1177/15333175211055325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Investigators report greater parietal tau deposition and alternate frontoparietal network involvement in early onset Alzheimer's Disease (EOAD) with onset <65 years as compared with typical late onset AD (LOAD). To determine whether clinical brain MRI volumes reflect these differences in EOAD compared with LOAD. This study investigated the clinical MRI scans of 45 persons with Clinically Probable AD with onset <65 years, and compared them to 32 with Clinically Probable AD with onset ≥65 years. Brain volumes on their T1 MRI scans were quantified with a volumetric program. Receiver operating curve analyses were performed. Persons with EOAD had significantly smaller parietal lobes (volumetric percentiles) than LOAD. Late onset Alzheimer's Disease had a smaller left putamen and hippocampus. Area Under the Curve was 96.5% with brain region delineation of EOAD compared to LOAD. This study indicates parietal atrophy less than 30% of normal on clinical MRI scans is suggestive of EOAD compared to LOAD.
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Affiliation(s)
- Somayeh Meysami
- Department of Neurology, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
| | - Cyrus A. Raji
- Mallinckrodt Institute of Radiology, Division of Neuroradiology, Washington University in St Louis, St Louis, MO, USA
| | - David A. Merrill
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
- Providence and St Johns Health Center, Pacific Neuroscience Institute, Santa Monica, CA, USA
| | - Verna R. Porter
- Department of Neurology, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
- Providence and St Johns Health Center, Pacific Neuroscience Institute, Santa Monica, CA, USA
| | - Mario F. Mendez
- Department of Neurology, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
- Department of Psychiatry & Biobehavioral Sciences, David Geffen School of Medicine at University of California, Los Angeles, CA, USA
- V.A. Greater Los Angeles Healthcare System, Los Angeles, CA, USA
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Xu SW, Xi JH, Lin C, Wang XY, Fu LY, Kralik SF, Chen ZQ. Cognitive decline and white matter changes in mesial temporal lobe epilepsy. Medicine (Baltimore) 2018; 97:e11803. [PMID: 30113469 PMCID: PMC6113048 DOI: 10.1097/md.0000000000011803] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Noninvasive imaging plays a pivotal role in assessing the brain structural and functional changes in presurgical mesial temporal lobe epilepsy (MTLE) patients. Our goal was to study the relationship between the changes of cerebral white matter (WM) and cognitive functions in MTLE patients.Voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) MRI were performed on 24 right-handed MTLE patients (12 with left MTLE and 12 with right MTLE) and 12 matching healthy controls. Gray matter (GM), WM, and whole brain (WB) volumes were measured with VBM while fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were measured with TBSS. All patients and controls also underwent Montreal Cognitive Assessment (MoCA) before MRI.WM volume and the ratio of WM volume versus WB volume were significantly lower in MTLE patients compared with controls. WM volume in MTLE patients had a positive correlation with MoCA score (r = 0.71, P < .001) and a negative correlation with the duration of epilepsy (r = -0.693, P < .001). Volumetric differences were mainly located in the corpus callosum, uncinate fasciculus, inferior longitudinal fasciculus, and superior longitudinal fasciculus. FA of both left MTLE and right MTLE groups was significantly decreased, while MD, AD, and RD were significantly increased. Most left MTLE patients showed bilateral WM fiber tract changes versus ipsilateral changes for right MTLE patients.Changes in DTI parameters and WM volume were found in MTLE patients and more ipsilateral changes were seen with right-sided MTLE. Cognitive changes of MTLE patients were found to be correlated with the changes in WM structure. These findings not only provide useful information for lateralization of the seizure focus but can also be used to explain functional connectivity disorders which may be an important physiological basis for cognitive changes in patients with MTLE.
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Affiliation(s)
- Shang-wen Xu
- Department of Medical Imaging, Fuzhou General Hospital, Xi’erhuan Beilu, Fuzhou, Fujian, PR China
| | - Ji-hui Xi
- Department of Medical Imaging, Fuzhou General Hospital, Xi’erhuan Beilu, Fuzhou, Fujian, PR China
| | - Chen Lin
- DABR Department of Radiology Mayo Clinic
| | - Xiao-yang Wang
- Department of Medical Imaging, Fuzhou General Hospital, Xi’erhuan Beilu, Fuzhou, Fujian, PR China
| | - Li-yuan Fu
- Department of Medical Imaging, Fuzhou General Hospital, Xi’erhuan Beilu, Fuzhou, Fujian, PR China
| | - Stephen Francis Kralik
- Department of Radiology and Imaging Science, Indiana University School of Medicine, Indianapolis, IN
| | - Zi-qian Chen
- Department of Medical Imaging, Fuzhou General Hospital, Xi’erhuan Beilu, Fuzhou, Fujian, PR China
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Jung WS, Um YH, Kang DW, Lee CU, Woo YS, Bahk WM, Lim HK. Diagnostic Validity of an Automated Probabilistic Tractography in Amnestic Mild Cognitive Impairment. CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE 2018; 16:144-152. [PMID: 29739127 PMCID: PMC5953013 DOI: 10.9758/cpn.2018.16.2.144] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 11/15/2016] [Accepted: 11/22/2016] [Indexed: 11/18/2022]
Abstract
Objective Although several prior works showed the white matter (WM) integrity changes in amnestic mild cognitive impairment (aMCI) and Alzheimer’s disease, it is still unclear the diagnostic accuracy of the WM integrity measurements using diffusion tensor imaging (DTI) in discriminating aMCI from normal controls. The aim of this study is to explore diagnostic validity of whole brain automated probabilistic tractography in discriminating aMCI from normal controls. Methods One hundred-two subjects (50 aMCI and 52 normal controls) were included and underwent DTI scans. Whole brain WM tracts were reconstructed with automated probabilistic tractography. Fractional anisotropy (FA) and mean diffusivity (MD) values of the memory related WM tracts were measured and compared between the aMCI and the normal control groups. In addition, the diagnostic validities of these WM tracts were evaluated. Results Decreased FA and increased MD values of memory related WM tracts were observed in the aMCI group compared with the control group. Among FA and MD value of each tract, the FA value of left cingulum angular bundle showed the highest area under the curve (AUC) of 0.85 with a sensitivity of 88.2%, a specificity of 76.9% in differentiating MCI patients from control subjects. Furthermore, the combination FA values of WM integrity measures of memory related WM tracts showed AUC value of 0.98, a sensitivity of 96%, a specificity of 94.2%. Conclusion Our results with good diagnostic validity of WM integrity measurements suggest DTI might be promising neuroimaging tool for early detection of aMCI and AD patients.
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Affiliation(s)
- Won Sang Jung
- Department of Radiology, St. Vincent Hospital, Suwon, Korea
| | - Yoo Hyun Um
- Department of Psychiatry, St. Vincent Hospital, Suwon, Korea
| | - Dong Woo Kang
- Department of Psychiatry, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Chang Uk Lee
- Department of Psychiatry, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Young Sup Woo
- Department of Psychiatry, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Won-Myong Bahk
- Department of Psychiatry, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Hyun Kook Lim
- Department of Psychiatry, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
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10
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Pietroboni AM, Scarioni M, Carandini T, Basilico P, Cadioli M, Giulietti G, Arighi A, Caprioli M, Serra L, Sina C, Fenoglio C, Ghezzi L, Fumagalli GG, De Riz MA, Calvi A, Triulzi F, Bozzali M, Scarpini E, Galimberti D. CSF β-amyloid and white matter damage: a new perspective on Alzheimer's disease. J Neurol Neurosurg Psychiatry 2018; 89:352-357. [PMID: 29054920 DOI: 10.1136/jnnp-2017-316603] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Revised: 09/13/2017] [Accepted: 09/28/2017] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To assess the connection between amyloid pathology and white matter (WM) macrostructural and microstructural damage in demented patients compared with controls. METHODS Eighty-five participants were recruited: 65 with newly diagnosed Alzheimer's disease (AD), non-AD dementia or mild cognitive impairment and 20 age-matched and sex-matched healthy controls. β-amyloid1-42 (Aβ) levels were determined in cerebrospinal fluid (CSF) samples from all patients and five controls. Among patients, 42 had pathological CSF Aβ levels (Aβ(+)), while 23 had normal CSF Aβ levels (Aβ(-)). All participants underwent neurological examination, neuropsychological testing and brain MRI. We used T2-weighted scans to quantify WM lesion loads (LLs) and diffusion-weighted images to assess their microstructural substrate. Non-parametric statistical tests were used for between-group comparisons and multiple regression analyses. RESULTS We found an increased WM-LL in Aβ(+) compared with both, healthy controls (p=0.003) and Aβ(-) patients (p=0.02). Interestingly, CSF Aβ concentration was the best predictor of patients' WM-LL (r=-0.30, p<0.05) when using age as a covariate. Lesion apparent diffusion coefficient value was higher in all patients than in controls (p=0.0001) and correlated with WM-LL (r=0.41, p=0.001). In Aβ(+), WM-LL correlated with WM microstructural damage in the left peritrigonal WM (p<0.0001). CONCLUSIONS WM damage is crucial in AD pathogenesis. The correlation between CSF Aβ levels and WM-LL suggests a direct link between amyloid pathology and WM macrostructural and microstructural damage.
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Affiliation(s)
- Anna M Pietroboni
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Marta Scarioni
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Tiziana Carandini
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Paola Basilico
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Marcello Cadioli
- Department of Pathophysiology and Transplantation, Neuroradiology Unit, University of Milan, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | | | - Andrea Arighi
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Michela Caprioli
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Laura Serra
- Neuroimaging Laboratory, Santa Lucia Foundation IRCCS, Rome, Italy
| | - Clara Sina
- Department of Pathophysiology and Transplantation, Neuroradiology Unit, University of Milan, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Chiara Fenoglio
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Laura Ghezzi
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Giorgio G Fumagalli
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Milena A De Riz
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Alberto Calvi
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Fabio Triulzi
- Department of Pathophysiology and Transplantation, Neuroradiology Unit, University of Milan, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Marco Bozzali
- Neuroimaging Laboratory, Santa Lucia Foundation IRCCS, Rome, Italy.,Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, UK
| | - Elio Scarpini
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
| | - Daniela Galimberti
- Department of Pathophysiology and Transplantation, Neurodegenerative Disease Unit, University of Milan, Centro Dino Ferrari, Fondazione Cà Granda, IRCCS Ospedale Maggiore Policlinico, Milan, Italy
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11
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Filippi M, Basaia S, Canu E, Imperiale F, Meani A, Caso F, Magnani G, Falautano M, Comi G, Falini A, Agosta F. Brain network connectivity differs in early-onset neurodegenerative dementia. Neurology 2017; 89:1764-1772. [PMID: 28954876 PMCID: PMC5664301 DOI: 10.1212/wnl.0000000000004577] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 07/19/2017] [Indexed: 12/20/2022] Open
Abstract
OBJECTIVE To investigate functional brain network architecture in early-onset Alzheimer disease (EOAD) and behavioral variant frontotemporal dementia (bvFTD). METHODS Thirty-eight patients with bvFTD, 37 patients with EOAD, and 32 age-matched healthy controls underwent 3D T1-weighted and resting-state fMRI. Graph analysis and connectomics assessed global and local functional topologic network properties, regional functional connectivity, and intrahemispheric and interhemispheric between-lobe connectivity. RESULTS Despite similarly extensive cognitive impairment relative to controls, patients with EOAD showed severe global functional network alterations (lower mean nodal strength, local efficiency, clustering coefficient, and longer path length), while patients with bvFTD showed relatively preserved global functional brain architecture. Patients with bvFTD demonstrated reduced nodal strength in the frontoinsular lobe and a relatively focal altered functional connectivity of frontoinsular and temporal regions. Functional connectivity breakdown in the posterior brain nodes, particularly in the parietal lobe, differentiated patients with EOAD from those with bvFTD. While EOAD was associated with widespread loss of both intrahemispheric and interhemispheric functional correlations, bvFTD showed a preferential disruption of the intrahemispheric connectivity. CONCLUSIONS Disease-specific patterns of functional network topology and connectivity alterations were observed in patients with EOAD and bvFTD. Graph analysis and connectomics may aid clinical diagnosis and help elucidate pathophysiologic differences between neurodegenerative dementias.
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Affiliation(s)
- Massimo Filippi
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy.
| | - Silvia Basaia
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Elisa Canu
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Francesca Imperiale
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Alessandro Meani
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Francesca Caso
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Giuseppe Magnani
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Monica Falautano
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Giancarlo Comi
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Andrea Falini
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Federica Agosta
- From the Neuroimaging Research Unit (M. Filippi, S.B., E.C., F.I., A.M., F.C., F.A.), Department of Neurology (M. Filippi, G.M., M. Falautano, G.C.), Institute of Experimental Neurology, Division of Neuroscience, and Department of Neuroradiology and CERMAC (A.F.), Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
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12
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Canu E, Agosta F, Mandic-Stojmenovic G, Stojković T, Stefanova E, Inuggi A, Imperiale F, Copetti M, Kostic VS, Filippi M. Multiparametric MRI to distinguish early onset Alzheimer's disease and behavioural variant of frontotemporal dementia. NEUROIMAGE-CLINICAL 2017; 15:428-438. [PMID: 28616383 PMCID: PMC5458769 DOI: 10.1016/j.nicl.2017.05.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 05/12/2017] [Accepted: 05/25/2017] [Indexed: 12/11/2022]
Abstract
This prospective study explored whether an approach combining structural [cortical thickness and white matter (WM) microstructure] and resting state functional MRI can aid differentiation between 62 early onset Alzheimer's disease (EOAD) and 27 behavioural variant of frontotemporal dementia (bvFTD) patients. Random forest and receiver operator characteristic curve analyses assessed the ability of MRI in classifying the two clinical syndromes. All patients showed a distributed pattern of brain alterations relative to controls. Compared to bvFTD, EOAD patients showed bilateral inferior parietal cortical thinning and decreased default mode network functional connectivity. Compared to EOAD, bvFTD patients showed bilateral orbitofrontal and temporal cortical thinning, and WM damage of the corpus callosum, bilateral uncinate fasciculus, and left superior longitudinal fasciculus. Random forest analysis revealed that left inferior parietal cortical thickness (accuracy 0.78, specificity 0.76, sensitivity 0.83) and WM integrity of the right uncinate fasciculus (accuracy 0.81, specificity 0.96, sensitivity 0.43) were the best predictors of clinical diagnosis. The combination of cortical thickness and DT MRI measures was able to distinguish patients with EOAD and bvFTD with accuracy 0.82, specificity 0.76, and sensitivity 0.96. The diagnostic ability of MRI models was confirmed in a subsample of patients with biomarker-based clinical diagnosis. Multiparametric MRI is useful to identify brain alterations which are specific to EOAD and bvFTD. A severe cortical involvement is suggestive of EOAD, while a prominent WM damage is indicative of bvFTD. Multimodal MRI distinguishes in vivo EOAD and bvFTD patients EOAD and bvFTD show a distributed pattern of structural brain alterations A severe cortical involvement is suggestive of EOAD relative to bvFTD A prominent WM damage is indicative of bvFTD relative to EOAD
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Key Words
- ACE-R, Addenbrooke's Cognitive Examination-revised
- Behavioural variant of frontotemporal dementia
- CC, corpus callosum
- CSF, cerebrospinal fluid
- Cortical thickness
- DMN, default mode network
- DT, diffusion tensor
- Diagnosis
- EOAD, early onset Alzheimer's disease
- Early onset Alzheimer's disease
- GM, grey matter
- IC, independent component
- ILF, inferior longitudinal fasciculus
- LOAD, late onset Alzheimer's disease
- MNI, Montreal Neurological Institute
- NVI, Normalized Variable Importance
- RS fMRI, resting state functional MRI
- RSN, resting state network
- Resting state functional MRI
- SLF, superior longitudinal fasciculus
- TFCE, threshold-free cluster enhancement
- WM, white matter
- White matter (WM) damage
- bvFTD, behavioural variant frontotemporal dementia
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Affiliation(s)
- Elisa Canu
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, via Olgettina 60, 20132 Milan, Italy
| | - Federica Agosta
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, via Olgettina 60, 20132 Milan, Italy
| | - Gorana Mandic-Stojmenovic
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, via Olgettina 60, 20132 Milan, Italy; Clinic of Neurology, Faculty of Medicine, University of Belgrade, Dr Subotića 6, PO Box 12, 11129 Belgrade 102, Serbia
| | - Tanja Stojković
- Clinic of Neurology, Faculty of Medicine, University of Belgrade, Dr Subotića 6, PO Box 12, 11129 Belgrade 102, Serbia
| | - Elka Stefanova
- Clinic of Neurology, Faculty of Medicine, University of Belgrade, Dr Subotića 6, PO Box 12, 11129 Belgrade 102, Serbia
| | - Alberto Inuggi
- Unit of Robotics, Brain and Cognitive Sciences, Istituto Italiano di Tecnologia, Via Morego, 30, 16163 Genoa, Italy
| | - Francesca Imperiale
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, via Olgettina 60, 20132 Milan, Italy
| | - Massimiliano Copetti
- Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, Viale Cappuccini, San Giovanni Rotondo, 71013 Foggia, Italy
| | - Vladimir S Kostic
- Clinic of Neurology, Faculty of Medicine, University of Belgrade, Dr Subotića 6, PO Box 12, 11129 Belgrade 102, Serbia
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, via Olgettina 60, 20132 Milan, Italy; Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, via Olgettina 60, 20132 Milan, Italy.
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13
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Slattery CF, Zhang J, Paterson RW, Foulkes AJM, Carton A, Macpherson K, Mancini L, Thomas DL, Modat M, Toussaint N, Cash DM, Thornton JS, Henley SMD, Crutch SJ, Alexander DC, Ourselin S, Fox NC, Zhang H, Schott JM. ApoE influences regional white-matter axonal density loss in Alzheimer's disease. Neurobiol Aging 2017; 57:8-17. [PMID: 28578156 PMCID: PMC5538347 DOI: 10.1016/j.neurobiolaging.2017.04.021] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 04/14/2017] [Accepted: 04/22/2017] [Indexed: 01/10/2023]
Abstract
Mechanisms underlying phenotypic heterogeneity in young onset Alzheimer disease (YOAD) are poorly understood. We used diffusion tensor imaging and neurite orientation dispersion and density imaging (NODDI) with tract-based spatial statistics to investigate apolipoprotein (APOE) ε4 modulation of white-matter damage in 37 patients with YOAD (22, 59% APOE ε4 positive) and 23 age-matched controls. Correlation between neurite density index (NDI) and neuropsychological performance was assessed in 4 white-matter regions of interest. White-matter disruption was more widespread in ε4+ individuals but more focal (posterior predominant) in the absence of an ε4 allele. NODDI metrics indicate fractional anisotropy changes are underpinned by combinations of axonal loss and morphological change. Regional NDI in parieto-occipital white matter correlated with visual object and spatial perception battery performance (right and left, both p = 0.02), and performance (nonverbal) intelligence (WASI matrices, right, p = 0.04). NODDI provides tissue-specific microstructural metrics of white-matter tract damage in YOAD, including NDI which correlates with focal cognitive deficits, and APOEε4 status is associated with different patterns of white-matter neurodegeneration.
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Affiliation(s)
- Catherine F Slattery
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK.
| | - Jiaying Zhang
- Department of Computer Science and Centre for Medical Image Computing, UCL, London, UK
| | - Ross W Paterson
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK
| | | | - Amelia Carton
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK
| | - Kirsty Macpherson
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK
| | - Laura Mancini
- Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK; Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, UCLH NHS Foundation Trust, London, UK
| | - David L Thomas
- Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK; Leonard Wolfson Experimental Neurology Centre, UCL Institute of Neurology, London, UK
| | - Marc Modat
- Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, UCL, London, UK
| | - Nicolas Toussaint
- Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, UCL, London, UK
| | - David M Cash
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK; Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, UCL, London, UK
| | - John S Thornton
- Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, London, UK; Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, UCLH NHS Foundation Trust, London, UK
| | - Susie M D Henley
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK
| | - Sebastian J Crutch
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK
| | - Daniel C Alexander
- Department of Computer Science and Centre for Medical Image Computing, UCL, London, UK
| | - Sebastien Ourselin
- Translational Imaging Group, Centre for Medical Image Computing, Department of Medical Physics and Biomedical Engineering, UCL, London, UK
| | - Nick C Fox
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK
| | - Hui Zhang
- Department of Computer Science and Centre for Medical Image Computing, UCL, London, UK
| | - Jonathan M Schott
- Department of Neurodegenerative Disease, Institute of Neurology, UCL, London, UK
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14
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Abstract
Early-onset Alzheimer disease (EOAD), with onset in individuals younger than 65 years, although overshadowed by the more common late-onset AD (LOAD), differs significantly from LOAD. EOAD comprises approximately 5% of AD and is associated with delays in diagnosis, aggressive course, and age-related psychosocial needs. One source of confusion is that a substantial percentage of EOAD are phenotypic variants that differ from the usual memory-disordered presentation of typical AD. The management of EOAD is similar to that for LOAD, but special emphasis should be placed on targeting the specific cognitive areas involved and more age-appropriate psychosocial support and education.
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Affiliation(s)
- Mario F Mendez
- Behavioral Neurology Program, David Geffen School of Medicine at UCLA, 300 Westwood Plaza, Suite B-200, Box 956975, Los Angeles, CA 90095, USA; Neurobehavior Unit, VA Greater Los Angeles Healthcare System, 11301 Wilshire Boulevard, Building 206, Los Angeles, CA 90073, USA.
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15
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Yoo K, Lee P, Chung MK, Sohn WS, Chung SJ, Na DL, Ju D, Jeong Y. Degree-based statistic and center persistency for brain connectivity analysis. Hum Brain Mapp 2017; 38:165-181. [PMID: 27593391 PMCID: PMC6866961 DOI: 10.1002/hbm.23352] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 05/18/2016] [Accepted: 08/08/2016] [Indexed: 12/16/2022] Open
Abstract
Brain connectivity analyses have been widely performed to investigate the organization and functioning of the brain, or to observe changes in neurological or psychiatric conditions. However, connectivity analysis inevitably introduces the problem of mass-univariate hypothesis testing. Although, several cluster-wise correction methods have been suggested to address this problem and shown to provide high sensitivity, these approaches fundamentally have two drawbacks: the lack of spatial specificity (localization power) and the arbitrariness of an initial cluster-forming threshold. In this study, we propose a novel method, degree-based statistic (DBS), performing cluster-wise inference. DBS is designed to overcome the above-mentioned two shortcomings. From a network perspective, a few brain regions are of critical importance and considered to play pivotal roles in network integration. Regarding this notion, DBS defines a cluster as a set of edges of which one ending node is shared. This definition enables the efficient detection of clusters and their center nodes. Furthermore, a new measure of a cluster, center persistency (CP) was introduced. The efficiency of DBS with a known "ground truth" simulation was demonstrated. Then they applied DBS to two experimental datasets and showed that DBS successfully detects the persistent clusters. In conclusion, by adopting a graph theoretical concept of degrees and borrowing the concept of persistence from algebraic topology, DBS could sensitively identify clusters with centric nodes that would play pivotal roles in an effect of interest. DBS is potentially widely applicable to variable cognitive or clinical situations and allows us to obtain statistically reliable and easily interpretable results. Hum Brain Mapp 38:165-181, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Kwangsun Yoo
- Department of Bio and Brain EngineeringKorea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
- KI for Health Science and Technology, Korea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
| | - Peter Lee
- Department of Bio and Brain EngineeringKorea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
- KI for Health Science and Technology, Korea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
| | - Moo K. Chung
- Department of Biostatistics and Medical Informatics and Waisman Laboratory for Brain Imaging and BehaviorUniversity of WisconsinMadisonWisconsin 53706
| | - William S. Sohn
- Department of Bio and Brain EngineeringKorea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
- Present address:
William S. Sohn is currently at Institute of Human Behavioral Medicine, Medical Research CenterSeoul National University
| | - Sun Ju Chung
- Department of NeurologyAsan Medical Center, University of Ulsan College of MedicineSeoulRepublic of Korea
| | - Duk L. Na
- Department of NeurologySamsung Medical Center, Sungkyunkwan University, School of MedicineSeoulRepublic of Korea
- Neuroscience Center, Samsung Medical Center, Sungkyunkwan University, School of MedicineSeoulRepublic of Korea
| | - Daheen Ju
- Department of Bio and Brain EngineeringKorea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
| | - Yong Jeong
- Department of Bio and Brain EngineeringKorea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
- KI for Health Science and Technology, Korea Advanced Institute of Science and TechnologyDaejeonRepublic of Korea
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16
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Chapleau M, Aldebert J, Montembeault M, Brambati SM. Atrophy in Alzheimer’s Disease and Semantic Dementia: An ALE Meta-Analysis of Voxel-Based Morphometry Studies. J Alzheimers Dis 2016; 54:941-955. [DOI: 10.3233/jad-160382] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Marianne Chapleau
- Département de Psychologie, Université de Montréal, Montréal, Québec, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal, Montréal, Québec, Canada
| | - Joséphine Aldebert
- Département de Psychologie, Université de Montréal, Montréal, Québec, Canada
| | - Maxime Montembeault
- Département de Psychologie, Université de Montréal, Montréal, Québec, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal, Montréal, Québec, Canada
| | - Simona M. Brambati
- Département de Psychologie, Université de Montréal, Montréal, Québec, Canada
- Centre de Recherche de l’Institut Universitaire de Gériatrie de Montréal, Montréal, Québec, Canada
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17
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Garcia-Martin E, Bambo MP, Marques ML, Satue M, Otin S, Larrosa JM, Polo V, Pablo LE. Ganglion cell layer measurements correlate with disease severity in patients with Alzheimer's disease. Acta Ophthalmol 2016; 94:e454-9. [PMID: 26895692 DOI: 10.1111/aos.12977] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 11/29/2015] [Indexed: 01/03/2023]
Abstract
PURPOSE To evaluate the thickness of the 10 retinal layers of patients with Alzheimer's disease (AD) using a new segmentation technology of the Spectralis optical coherence tomography (OCT) and to determine whether the thickness of specific layers predicts neurodegeneration or AD severity. METHODS Patients with AD (n = 150) and age-matched healthy controls (n = 75) were analysed using the segmentation application prototype to automatically segment all retinal layers in a macular scan. Thicknesses of each layer were compared between patients with AD and controls, and between patients with disease durations of less than or at least 3 years. Associations between retinal layer thicknesses, disease duration and AD severity were evaluated. RESULTS Patients with AD had reduced thickness in the retinal nerve fibre, ganglion cell, inner plexiform and outer nuclear layers (p < 0.05). The inner retinal layers were more affected in patients with long disease duration. Ganglion cell and retinal nerve fibre layer thicknesses were inversely correlated with AD duration and severity. Ganglion cell and inner plexiform layers thicknesses were predictive of axonal damage. CONCLUSIONS The segmentation application revealed ganglion cell and retinal layer atrophy in patients with AD compared with controls, especially in the inner layers of patients with long disease duration. Ganglion cell layer reduction was associated with increased axonal damage and may predict greater disease severity.
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Affiliation(s)
- Elena Garcia-Martin
- Ophthalmology Department; Miguel Servet University Hospital; Zaragoza Spain
- Aragon Institute of Health Research; IIS-Aragon; Zaragoza Spain
| | - Maria P. Bambo
- Ophthalmology Department; Miguel Servet University Hospital; Zaragoza Spain
- Aragon Institute of Health Research; IIS-Aragon; Zaragoza Spain
| | | | - Maria Satue
- Ophthalmology Department; Miguel Servet University Hospital; Zaragoza Spain
- Aragon Institute of Health Research; IIS-Aragon; Zaragoza Spain
| | - Sofia Otin
- Ophthalmology Department; Miguel Servet University Hospital; Zaragoza Spain
- Aragon Institute of Health Research; IIS-Aragon; Zaragoza Spain
| | - Jose M. Larrosa
- Ophthalmology Department; Miguel Servet University Hospital; Zaragoza Spain
- Aragon Institute of Health Research; IIS-Aragon; Zaragoza Spain
| | - Vicente Polo
- Ophthalmology Department; Miguel Servet University Hospital; Zaragoza Spain
- Aragon Institute of Health Research; IIS-Aragon; Zaragoza Spain
| | - Luis E. Pablo
- Aragon Institute of Health Research; IIS-Aragon; Zaragoza Spain
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18
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Migliaccio R, Agosta F, Possin KL, Canu E, Filippi M, Rabinovici GD, Rosen HJ, Miller BL, Gorno-Tempini ML. Mapping the Progression of Atrophy in Early- and Late-Onset Alzheimer's Disease. J Alzheimers Dis 2016; 46:351-64. [PMID: 25737041 DOI: 10.3233/jad-142292] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The term early-onset Alzheimer's disease (EOAD) identifies patients who meet criteria for AD, but show onset of symptoms before the age of 65. We map progression of gray matter atrophy in EOAD patients compared to late-onset AD (LOAD). T1-weighted MRI scans were obtained at diagnosis and one-year follow-up from 15 EOAD, 10 LOAD, and 38 age-matched controls. Voxel-based and tensor-based morphometry were used, respectively, to assess the baseline and progression of atrophy. At baseline, EOAD patients already showed a widespread atrophy in temporal, parietal, occipital, and frontal cortices. After one year, EOAD had atrophy progression in medial temporal and medial parietal cortices. At baseline, LOAD patients showed atrophy in the medial temporal regions only, and, after one year, an extensive pattern of atrophy progression in the same neocortical cortices of EOAD. Although atrophy mainly involved different lateral neocortical or medial temporal hubs at baseline, it eventually progressed along the same brain default-network regions in both groups. The cortical region showing a significant progression in both groups was the medial precuneus/posterior cingulate.
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19
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Weiler M, Agosta F, Canu E, Copetti M, Magnani G, Marcone A, Pagani E, Balthazar MLF, Comi G, Falini A, Filippi M. Following the Spreading of Brain Structural Changes in Alzheimer's Disease: A Longitudinal, Multimodal MRI Study. J Alzheimers Dis 2016; 47:995-1007. [PMID: 26401778 DOI: 10.3233/jad-150196] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Longitudinal MRI studies in Alzheimer's disease (AD) are one of the most reliable way to track brain changes along the course of the disease. OBJECTIVE To investigate the evolution of grey matter (GM) atrophy and white matter (WM) damage in AD patients, and to assess the relationships of MRI changes with baseline clinical and cognitive variables and their evolution over time. METHODS Clinical, neuropsychological, and MRI assessments (T1-weighted and diffusion tensor [DT]-MRI) were obtained from 14 patients with AD at baseline and after a 16 ± 3 month period. Lumbar puncture was obtained at study entry. At baseline, AD patients were compared to 37 controls. GM atrophy progression was assessed with tensor-based morphometry and GM volumes of interest, and WM damage progression using tract-based spatial statistics and tractography. RESULTS At baseline, patients showed cortical atrophy in the medial temporal and parietal regions and a widespread pattern of WM damage involving the corpus callosum, cingulum, and temporo-occipital, parietal, and frontal WM tracts. During follow up, AD patients showed total GM atrophy, while total WM volume did not change. GM tissue loss was found in frontal, temporal, and parietal regions. In addition, AD patients showed a progression of WM microstructural damage to the corpus callosum, cingulum, fronto-parietal and temporo-occipital connections bilaterally. Patients with higher baseline cerebrospinal fluid total tau showed greater WM integrity loss at follow up. GM and WM changes over time did not correlate with each other nor with cognitive evolution. CONCLUSION In AD, GM atrophy and WM tract damage are likely to progress, at least partially, independently. This study suggests that a multimodal imaging approach, which includes both T1-weighted and DT MR imaging, may provide additional markers to monitor disease progression.
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Affiliation(s)
- Marina Weiler
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy.,Laboratory of Neuroimaging, University of Campinas, Campinas, Brazil
| | - Federica Agosta
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Elisa Canu
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Massimiliano Copetti
- Biostatistics Unit, IRCCS-Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy
| | - Giuseppe Magnani
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Alessandra Marcone
- Department of Clinical Neurosciences, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Elisabetta Pagani
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | | | - Giancarlo Comi
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Andrea Falini
- Department of Neuroradiology and CERMAC, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy.,Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
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Montagne A, Nation DA, Pa J, Sweeney MD, Toga AW, Zlokovic BV. Brain imaging of neurovascular dysfunction in Alzheimer's disease. Acta Neuropathol 2016; 131:687-707. [PMID: 27038189 PMCID: PMC5283382 DOI: 10.1007/s00401-016-1570-0] [Citation(s) in RCA: 143] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 03/21/2016] [Accepted: 03/23/2016] [Indexed: 11/29/2022]
Abstract
Neurovascular dysfunction, including blood-brain barrier (BBB) breakdown and cerebral blood flow (CBF) dysregulation and reduction, are increasingly recognized to contribute to Alzheimer's disease (AD). The spatial and temporal relationships between different pathophysiological events during preclinical stages of AD, including cerebrovascular dysfunction and pathology, amyloid and tau pathology, and brain structural and functional changes remain, however, still unclear. Recent advances in neuroimaging techniques, i.e., magnetic resonance imaging (MRI) and positron emission tomography (PET), offer new possibilities to understand how the human brain works in health and disease. This includes methods to detect subtle regional changes in the cerebrovascular system integrity. Here, we focus on the neurovascular imaging techniques to evaluate regional BBB permeability (dynamic contrast-enhanced MRI), regional CBF changes (arterial spin labeling- and functional-MRI), vascular pathology (structural MRI), and cerebral metabolism (PET) in the living human brain, and examine how they can inform about neurovascular dysfunction and vascular pathophysiology in dementia and AD. Altogether, these neuroimaging approaches will continue to elucidate the spatio-temporal progression of vascular and neurodegenerative processes in dementia and AD and how they relate to each other.
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Affiliation(s)
- Axel Montagne
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Daniel A Nation
- Department of Psychology, University of Southern California, Los Angeles, CA, 90089, USA
| | - Judy Pa
- Department of Neurology, Institute for Neuroimaging and Informatics, University of Southern California, Los Angeles, CA, 90089, USA
| | - Melanie D Sweeney
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA
| | - Arthur W Toga
- Department of Neurology, Institute for Neuroimaging and Informatics, University of Southern California, Los Angeles, CA, 90089, USA
| | - Berislav V Zlokovic
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA, 90089, USA.
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21
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Canu E, Agosta F, Sarasso E, Volontè MA, Basaia S, Stojkovic T, Stefanova E, Comi G, Falini A, Kostic VS, Gatti R, Filippi M. Brain structural and functional connectivity in Parkinson's disease with freezing of gait. Hum Brain Mapp 2015; 36:5064-78. [PMID: 26359798 PMCID: PMC6869160 DOI: 10.1002/hbm.22994] [Citation(s) in RCA: 137] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 08/27/2015] [Accepted: 09/03/2015] [Indexed: 12/14/2022] Open
Abstract
OBJECTIVE To use a multimodal approach to assess brain structural pathways and resting state (RS) functional connectivity abnormalities in patients with Parkinson's disease and freezing of gait (PD-FoG). METHODS T1-weighted, diffusion tensor (DT) MRI and RS functional MRI (fMRI) were obtained from 22 PD-FoG patients and 35 controls on a 3.0 T MR scanner. Patients underwent clinical, motor, and neuropsychological evaluations. Gray matter (GM) volumes and white matter (WM) damage were assessed using voxel based morphometry and tract-based spatial statistics, respectively. The pedunculopontine tract (PPT) was studied using tractography. RS fMRI data were analyzed using a model free approach investigating the main sensorimotor and cognitive brain networks. Multiple regression models were performed to assess the relationships between structural, functional, and clinical/cognitive variables. Analysis of GM and WM structural abnormalities was replicated in an independent sample including 28 PD-FoG patients, 25 PD patients without FoG, and 30 healthy controls who performed MRI scans on a 1.5 T scanner. RESULTS Compared with controls, no GM atrophy was found in PD-FoG cases. PD-FoG patients showed WM damage of the PPT, corpus callosum, corticospinal tract, cingulum, superior longitudinal fasciculus, and WM underneath the primary motor, premotor, prefrontal, orbitofrontal, and inferior parietal cortices, bilaterally. In PD-FoG, right PTT damage was associated with a greater disease severity. Analysis on the independent PD sample showed similar findings in PD-FoG patients relative to controls as well as WM damage of the genu and body of the corpus callosum and right parietal WM in PD-FoG relative to PD no-FoG patients. RS fMRI analysis showed that PD-FoG is associated with a decreased functional connectivity of the primary motor cortex and supplementary motor area bilaterally in the sensorimotor network, frontoparietal regions in the default mode network, and occipital cortex in the visual associative network. CONCLUSIONS This study suggests that FoG in PD can be the result of a poor structural and functional integration between motor and extramotor (cognitive) neural systems.
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Affiliation(s)
- Elisa Canu
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Federica Agosta
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Elisabetta Sarasso
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
- Laboratory of Movement Analysis, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Maria Antonietta Volontè
- Department of Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Silvia Basaia
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Tanja Stojkovic
- Clinic of Neurology, Faculty of MedicineUniversity of BelgradeBelgradeSerbia
| | - Elka Stefanova
- Clinic of Neurology, Faculty of MedicineUniversity of BelgradeBelgradeSerbia
| | - Giancarlo Comi
- Department of Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Andrea Falini
- Department of Neuroradiology and CERMAC, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Vladimir S. Kostic
- Clinic of Neurology, Faculty of MedicineUniversity of BelgradeBelgradeSerbia
| | - Roberto Gatti
- Laboratory of Movement Analysis, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
- Department of Neurology, Division of NeuroscienceSan Raffaele Scientific Institute, Vita‐Salute San Raffaele UniversityMilanItaly
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In-vivo imaging of grey and white matter neuroinflammation in Alzheimer's disease: a positron emission tomography study with a novel radioligand, [18F]-FEPPA. Mol Psychiatry 2015; 20:1579-87. [PMID: 25707397 PMCID: PMC8026116 DOI: 10.1038/mp.2015.1] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 12/16/2014] [Accepted: 12/19/2014] [Indexed: 11/09/2022]
Abstract
Our primary aim was to compare neuroinflammation in cognitively intact control subjects and patients with Alzheimer's disease (AD) by using positron emission tomography (PET) with translocator protein 18 kDa (TSPO)-specific radioligand [(18)F]-FEPPA. [(18)F]-FEPPA PET scans were acquired on a high-resolution research tomograph in 21 patients with AD (47- 81 years) and 21 control subjects (49-82 years). They were analyzed by using a 2-tissue compartment model with arterial plasma input function. Differences in neuroinflammation, indexed as [(18)F]-FEPPA binding were compared, adjusting for differences in binding affinity class as determined by a single polymorphism in the TSPO gene (rs6971). In grey matter areas, [(18)F]-FEPPA was significantly higher in AD compared with healthy control subjects. Large increases were seen in the hippocampus, prefrontal, temporal, parietal and occipital cortex (average Cohen's d= 0.89). Voxel-based analyses confirmed significant clusters of neuroinflammation in the frontal, temporal and parietal cortex in patients with AD. In white matter, [(18)F]-FEPPA binding was elevated in the posterior limb of the internal capsule, and the cingulum bundle. Higher neuroinflammation in the parietal cortex (r= -0.7, P= 0.005), and posterior limb of the internal capsule (r= -0.8, P=0.001) was associated with poorer visuospatial function. In addition, a higher [(18)F]-FEPPA binding in the posterior limb of the internal capsule was associated with a greater impairment in language ability (r= -0.7, P=0.004). Elevated neuroinflammation can be detected in AD patients throughout the brain grey and white matter by using [(18)F]-FEPPA PET. Our results also suggest that neuroinflammation is associated with some cognitive deficits.
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Caso F, Agosta F, Filippi M. Insights into White Matter Damage in Alzheimer's Disease: From Postmortem to in vivo Diffusion Tensor MRI Studies. NEURODEGENER DIS 2015; 16:26-33. [DOI: 10.1159/000441422] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Accepted: 10/01/2015] [Indexed: 11/19/2022] Open
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Tellechea P, Pujol N, Esteve-Belloch P, Echeveste B, García-Eulate MR, Arbizu J, Riverol M. Early- and late-onset Alzheimer disease: Are they the same entity? Neurologia 2015; 33:244-253. [PMID: 26546285 DOI: 10.1016/j.nrl.2015.08.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 08/06/2015] [Accepted: 08/14/2015] [Indexed: 11/29/2022] Open
Abstract
Early-onset Alzheimer disease (EOAD), which presents in patients younger than 65 years, has frequently been described as having different features from those of late-onset Alzheimer disease (LOAD). This review analyses the most recent studies comparing the clinical presentation and neuropsychological, neuropathological, genetic, and neuroimaging findings of both types in order to determine whether EOAD and LOAD are different entities or distinct forms of the same entity. We observed consistent differences between clinical findings in EOAD and in LOAD. Fundamentally, the onset of EOAD is more likely to be marked by atypical symptoms, and cognitive assessments point to poorer executive and visuospatial functioning and praxis with less marked memory impairment. Alzheimer-type features will be more dense and widespread in neuropathology studies, with structural and functional neuroimaging showing greater and more diffuse atrophy extending to neocortical areas (especially the precuneus). In conclusion, available evidence suggests that EOAD and LOAD are 2 different forms of a single entity. LOAD is likely to be influenced by ageing-related processes.
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Affiliation(s)
- P Tellechea
- Departamento de Neurología, Clínica Universidad de Navarra, Pamplona, Navarra, España
| | - N Pujol
- Departamento de Neurología, Clínica Universidad de Navarra, Pamplona, Navarra, España
| | - P Esteve-Belloch
- Departamento de Neurología, Clínica Universidad de Navarra, Pamplona, Navarra, España
| | - B Echeveste
- Departamento de Neurología, Clínica Universidad de Navarra, Pamplona, Navarra, España
| | - M R García-Eulate
- Departamento de Radiología, Clínica Universidad de Navarra, Pamplona, Navarra, España
| | - J Arbizu
- Departamento de Medicina Nuclear, Clínica Universidad de Navarra, Pamplona, Navarra, España
| | - M Riverol
- Departamento de Neurología, Clínica Universidad de Navarra, Pamplona, Navarra, España.
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Caso F, Agosta F, Mattavelli D, Migliaccio R, Canu E, Magnani G, Marcone A, Copetti M, Falautano M, Comi G, Falini A, Filippi M. White Matter Degeneration in Atypical Alzheimer Disease. Radiology 2015; 277:162-72. [DOI: 10.1148/radiol.2015142766] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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26
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Agosta F, Galantucci S, Magnani G, Marcone A, Martinelli D, Antonietta Volontè M, Riva N, Iannaccone S, Ferraro PM, Caso F, Chiò A, Comi G, Falini A, Filippi M. MRI signatures of the frontotemporal lobar degeneration continuum. Hum Brain Mapp 2015; 36:2602-14. [PMID: 25821176 DOI: 10.1002/hbm.22794] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Revised: 02/16/2015] [Accepted: 03/11/2015] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To identify overlapping and unique grey (GM) and white matter (WM) signatures within the frontotemporal lobar degeneration (FTLD) continuum, and discriminate likely FTLD-TAU and FTLD-TDP patients using structural and diffusion tensor (DT) magnetic resonance imaging (MRI). METHODS T1-weighted and DT MRI were collected from 121 subjects: 35 motor neuron disease (MND), 14 behavioral variant of frontotemporal dementia, 12 semantic and 11 nonfluent primary progressive aphasia, 21 progressive supranuclear palsy syndrome patients, and 28 healthy controls. Patterns of GM atrophy were established using voxel-based morphometry. Tract-based spatial statistics was used to perform a WM voxelwise analysis of mean diffusivity and fractional anisotropy. RESULTS In all clinical FTLD phenotypes, the pattern of WM damage was more distributed than that of GM atrophy. All patient groups, with the exception of MND cases with a pure motor syndrome, shared a focal GM atrophy centered around the dorsolateral and medial frontal cortex and a largely overlapping pattern of WM damage involving the genu and body of the corpus callosum and ventral frontotemporal and dorsal frontoparietal WM pathways. Surrounding this common area, phenotype (symptom)-specific GM and WM regions of damage were found in each group. CONCLUSIONS In the FTLD spectrum, WM disruption is more severe than GM damage. Frontal cortex and WM pathways represent the common target of neurodegeneration in these conditions. The topographic pattern of damage supports a "prion-like" protein propagation through WM connections as underlying mechanism of the stereotyped progression of FTLD.
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Affiliation(s)
| | | | - Giuseppe Magnani
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience
| | - Alessandra Marcone
- Department of Clinical Neurosciences, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | | | | | - Nilo Riva
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience
| | - Sandro Iannaccone
- Department of Clinical Neurosciences, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | | | | | - Adriano Chiò
- Department of Neuroscience, ALS Center, "Rita Levi Montalcini" University of Torino, Torino, Italy
| | - Giancarlo Comi
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience
| | - Andrea Falini
- Department of Neuroradiology and CERMAC, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Massimo Filippi
- Neuroimaging Research Unit.,Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience
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Douet V, Chang L. Fornix as an imaging marker for episodic memory deficits in healthy aging and in various neurological disorders. Front Aging Neurosci 2015; 6:343. [PMID: 25642186 PMCID: PMC4294158 DOI: 10.3389/fnagi.2014.00343] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 12/14/2014] [Indexed: 01/12/2023] Open
Abstract
The fornix is a part of the limbic system and constitutes the major efferent and afferent white matter tracts from the hippocampi. The underdevelopment of or injuries to the fornix are strongly associated with memory deficits. Its role in memory impairments was suggested long ago with cases of surgical forniceal transections. However, recent advances in brain imaging techniques, such as diffusion tensor imaging, have revealed that macrostructural and microstructural abnormalities of the fornix correlated highly with declarative and episodic memory performance. This structure appears to provide a robust and early imaging predictor for memory deficits not only in neurodegenerative and neuroinflammatory diseases, such as Alzheimer's disease and multiple sclerosis, but also in schizophrenia and psychiatric disorders, and during neurodevelopment and “typical” aging. The objective of the manuscript is to present a systematic review regarding published brain imaging research on the fornix, including the development of its tracts, its role in various neurological diseases, and its relationship to neurocognitive performance in human studies.
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Affiliation(s)
- Vanessa Douet
- Department of Medicine, John A. Burns School of Medicine, University of Hawaii Honolulu, HI, USA
| | - Linda Chang
- Department of Medicine, John A. Burns School of Medicine, University of Hawaii Honolulu, HI, USA
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Yin RH, Tan L, Liu Y, Wang WY, Wang HF, Jiang T, Radua J, Zhang Y, Gao J, Canu E, Migliaccio R, Filippi M, Gorno-Tempini ML, Yu JT. Multimodal Voxel-Based Meta-Analysis of White Matter Abnormalities in Alzheimer's Disease. J Alzheimers Dis 2015; 47:495-507. [PMID: 26401571 PMCID: PMC5757541 DOI: 10.3233/jad-150139] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
An increasing number of MRI investigations suggest that patients with Alzheimer's disease (AD) show not only gray matter decreases but also white matter (WM) abnormalities, including WM volume (WMV) deficits and integrity disruption of WM pathways. In this study, we applied multimodal voxel-wise meta-analytical methods to study WMV and fractional anisotropy in AD. Fourteen studies including 723 participants (340 with AD and 383 controls) were involved. The meta-analysis was performed using effect size signed differential mapping. Significant WMV reductions were observed in bilateral inferior temporal gyrus, splenium of corpus callosum, right parahippocampal gyrus, and hippocampus. Decreased fractional anisotropy was identified mainly in left posterior limb of internal capsule, left anterior corona radiata, left thalamus, and left caudate nucleus. Significant decreases of both WMV and fractional anisotropy were found in left caudate nucleus, left superior corona radiata, and right inferior temporal gyrus. Most findings showed to be highly replicable in the jackknife sensitivity analyses. In conclusion, AD patients show widespread WM abnormalities mainly in bilateral structures related to advanced mental and nervous activities.
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Affiliation(s)
- Rui-Hua Yin
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China
- College of Medicine and Pharmaceutics, Ocean University of China, Qingdao, China
- Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Qingdao, China
| | - Yong Liu
- Brainnetome Center, National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Wen-Ying Wang
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China
| | - Hui-Fu Wang
- Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Qingdao, China
| | - Teng Jiang
- Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Qingdao, China
| | - Joaquim Radua
- Department of Psychosis Studies, Institute of Psychiatry, King’s College London, London, UK
- Research Unit, FIDMAG – CIBERSAM, Sant Boi de Llobregat, Barcelona, Spain
| | - Yu Zhang
- Center for Imaging of Neurodegenerative Diseases, Department of Veterans Affairs Medical Center, San Francisco, CA, USA
| | - Junling Gao
- Department of Medicine, LKS Faculty of Medicine, the University of Hong Kong, Hong Kong SAR
| | - Elisa Canu
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina, Milan, Italy
| | - Raffaella Migliaccio
- INSERM, U1127, Institut du Cerveau et de la Moelle Epiniere (ICM), Hopital de la Pitie-Salpetriere, Paris, France
- Department of Neurology, Institut de la memoire et de la maladie d’Alzheimer, Hopital de la Pitie-Salpetriere, AP-HP, Paris, France
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Via Olgettina, Milan, Italy
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Maria Luisa Gorno-Tempini
- Memory and Aging Center, Department of Neurology, University of California at San Francisco, San Francisco, CA, USA
| | - Jin-Tai Yu
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China
- Department of Neurology, Qingdao Municipal Hospital, Nanjing Medical University, Qingdao, China
- Memory and Aging Center, Department of Neurology, University of California at San Francisco, San Francisco, CA, USA
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29
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Lobzin VY. Comprehensive early diagnosis of cognitive impairment. Zh Nevrol Psikhiatr Im S S Korsakova 2015; 115:72-79. [DOI: 10.17116/jnevro201511511172-79] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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30
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Agosta F, Dalla Libera D, Spinelli EG, Finardi A, Canu E, Bergami A, Bocchio Chiavetto L, Baronio M, Comi G, Martino G, Matteoli M, Magnani G, Verderio C, Furlan R. Myeloid microvesicles in cerebrospinal fluid are associated with myelin damage and neuronal loss in mild cognitive impairment and Alzheimer disease. Ann Neurol 2014; 76:813-25. [DOI: 10.1002/ana.24235] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 07/25/2014] [Accepted: 07/25/2014] [Indexed: 12/11/2022]
Affiliation(s)
- Federica Agosta
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | - Dacia Dalla Libera
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | - Edoardo Gioele Spinelli
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | - Annamaria Finardi
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | - Elisa Canu
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | - Alessandra Bergami
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | | | | | - Giancarlo Comi
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
- Vita-Salute San Raffaele University; Milan
| | - Gianvito Martino
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | - Michela Matteoli
- CNR Institute of Neuroscience and Department of Medical Pharmacology; Milan
- Istituto Clinico Humanitas IRCCS; Milan Italy
| | - Giuseppe Magnani
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
| | - Claudia Verderio
- CNR Institute of Neuroscience and Department of Medical Pharmacology; Milan
- Istituto Clinico Humanitas IRCCS; Milan Italy
| | - Roberto Furlan
- Division of Neuroscience, Institute of Experimental Neurology; Scientific Institute San Raffaele; Milan
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Acosta-Cabronero J, Nestor PJ. Diffusion tensor imaging in Alzheimer's disease: insights into the limbic-diencephalic network and methodological considerations. Front Aging Neurosci 2014; 6:266. [PMID: 25324775 PMCID: PMC4183111 DOI: 10.3389/fnagi.2014.00266] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Accepted: 09/15/2014] [Indexed: 11/25/2022] Open
Abstract
Glucose hypometabolism and gray matter atrophy are well known consequences of Alzheimer's disease (AD). Studies using these measures have shown that the earliest clinical stages, in which memory impairment is a relatively isolated feature, are associated with degeneration in an apparently remote group of areas—mesial temporal lobe (MTL), diencephalic structures such as anterior thalamus and mammillary bodies, and posterior cingulate. These sites are thought to be strongly anatomically inter-connected via a limbic-diencephalic network. Diffusion tensor imaging or DTI—an imaging technique capable of probing white matter tissue microstructure—has recently confirmed degeneration of the white matter connections of the limbic-diencephalic network in AD by way of an unbiased analysis strategy known as tract-based spatial statistics (TBSS). The present review contextualizes the relevance of these findings, in which the fornix is likely to play a fundamental role in linking MTL and diencephalon. An interesting by-product of this work has been in showing that alterations in diffusion behavior are complex in AD—while early studies tended to focus on fractional anisotropy, recent work has highlighted that this measure is not the most sensitive to early changes. Finally, this review will discuss in detail several technical aspects of DTI both in terms of image acquisition and TBSS analysis as both of these factors have important implications to ensure reliable observations are made that inform understanding of neurodegenerative diseases.
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Affiliation(s)
- Julio Acosta-Cabronero
- Brain Plasticity and Neurodegeneration Group, German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
| | - Peter J Nestor
- Brain Plasticity and Neurodegeneration Group, German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
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Filippi CG, Cauley KA. Lesions of the Corpus Callosum and Other Commissural Fibers: Diffusion Tensor Studies. Semin Ultrasound CT MR 2014; 35:445-58. [DOI: 10.1053/j.sult.2014.06.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Adluru N, Destiche DJ, Lu SYF, Doran ST, Birdsill AC, Melah KE, Okonkwo OC, Alexander AL, Dowling NM, Johnson SC, Sager MA, Bendlin BB. White matter microstructure in late middle-age: Effects of apolipoprotein E4 and parental family history of Alzheimer's disease. NEUROIMAGE-CLINICAL 2014; 4:730-42. [PMID: 24936424 PMCID: PMC4053649 DOI: 10.1016/j.nicl.2014.04.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 04/16/2014] [Accepted: 04/17/2014] [Indexed: 01/05/2023]
Abstract
INTRODUCTION Little is still known about the effects of risk factors for Alzheimer's disease (AD) on white matter microstructure in cognitively healthy adults. The purpose of this cross-sectional study was to assess the effect of two well-known risk factors for AD, parental family history and APOE4 genotype. METHODS This study included 343 participants from the Wisconsin Registry for Alzheimer's Prevention, who underwent diffusion tensor imaging (DTI). A region of interest analysis was performed on fractional anisotropy maps, in addition to mean, radial, and axial diffusivity maps, aligned to a common template space using a diffeomorphic, tensor-based registration method. The analysis focused on brain regions known to be affected in AD including the corpus callosum, superior longitudinal fasciculus, fornix, cingulum, and uncinate fasciculus. Analyses assessed the impact of APOE4, parental family history of AD, age, and sex on white matter microstructure in late middle-aged participants (aged 47-76 years). RESULTS Both APOE4 and parental family history were associated with microstructural white matter differences. Participants with parental family history of AD had higher FA in the genu of the corpus callosum and the superior longitudinal fasciculus. We observed an interaction between family history and APOE4, where participants who were family history positive but APOE4 negative had lower axial diffusivity in the uncinate fasciculus, and participants who were both family history positive and APOE4 positive had higher axial diffusivity in this region. We also observed an interaction between APOE4 and age, whereby older participants (=65 years of age) who were APOE4 carriers, had higher MD in the superior longitudinal fasciculus and in the portion of the cingulum bundle running adjacent to the cingulate cortex, compared to non-carriers. Older participants who were APOE4 carriers also showed higher radial diffusivity in the genu compared to non-carriers. Across all participants, age had an effect on FA, MD, and axial and radial diffusivities. Sex differences were observed in FA and radial diffusivity. CONCLUSION APOE4 genotype, parental family history of AD, age, and sex are all associated with microstructural white matter differences in late middle-aged adults. In participants at risk for AD, alterations in diffusion characteristics-both expected and unexpected-may represent cellular changes occurring at the earliest disease stages, but further work is needed. Higher mean, radial, and axial diffusivities were observed in participants who are more likely to be experiencing later stage preclinical pathology, including participants who were both older and carried APOE4, or who were positive for both APOE4 and parental family history of AD.
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Affiliation(s)
- Nagesh Adluru
- Waisman Laboratory for Brain Imaging and Behavior, Madison, WI, USA
| | | | | | - Samuel T Doran
- Waisman Laboratory for Brain Imaging and Behavior, Madison, WI, USA
| | - Alex C Birdsill
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
| | - Kelsey E Melah
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
| | - Ozioma C Okonkwo
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
| | - Andrew L Alexander
- Waisman Laboratory for Brain Imaging and Behavior, Madison, WI, USA ; Department of Medical Physics, University of Wisconsin School of Medicine and Public Health, 1111 Highland Ave, Madison, WI 53705, USA ; University of Wisconsin School of Medicine and Public Health, Department of Psychiatry, 6001 Research Park Blvd, Madison, WI 53719, USA
| | - N Maritza Dowling
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA ; Department of Biostatistics and Medical Informatics, 600 Highland Avenue, Madison, WI 53792, USA
| | - Sterling C Johnson
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA ; Geriatric Research, Education and Clinical Center (GRECC), William S. Middleton Memorial Veteran's Hospital, 2500 Overlook Terrace, Madison, WI 53705, USA ; Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, 7818 Big Sky Drive, Madison, WI 53719, USA
| | - Mark A Sager
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA ; Geriatric Research, Education and Clinical Center (GRECC), William S. Middleton Memorial Veteran's Hospital, 2500 Overlook Terrace, Madison, WI 53705, USA ; Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, 7818 Big Sky Drive, Madison, WI 53719, USA
| | - Barbara B Bendlin
- Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, Department of Medicine, 600 Highland Avenue, Madison, WI 53792, USA
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