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Item The Alzheimer's Disease Neuroimaging Initiative: A review of papers published since its inception(Wiley, 2013) Weiner, Michael W.; Veitch, Dallas P.; Aisen, Paul S.; Beckett, Laurel A.; Cairns, Nigel J.; Green, Robert C.; Harvey, Danielle; Jack, Clifford R.; Jagust, William; Liu, Enchi; Morris, John C.; Petersen, Ronald C.; Saykin, Andrew J.; Schmidt, Mark E.; Shaw, Leslie; Shen, Li; Siuciak, Judith A.; Soares, Holly; Toga, Arthur W.; Trojanowski, John Q.; Alzheimer's Disease Neuroimaging Initiative; Radiology and Imaging Sciences, School of MedicineThe Alzheimer's Disease Neuroimaging Initiative (ADNI) is an ongoing, longitudinal, multicenter study designed to develop clinical, imaging, genetic, and biochemical biomarkers for the early detection and tracking of Alzheimer's disease (AD). The study aimed to enroll 400 subjects with early mild cognitive impairment (MCI), 200 subjects with early AD, and 200 normal control subjects; $67 million funding was provided by both the public and private sectors, including the National Institute on Aging, 13 pharmaceutical companies, and 2 foundations that provided support through the Foundation for the National Institutes of Health. This article reviews all papers published since the inception of the initiative and summarizes the results as of February 2011. The major accomplishments of ADNI have been as follows: (1) the development of standardized methods for clinical tests, magnetic resonance imaging (MRI), positron emission tomography (PET), and cerebrospinal fluid (CSF) biomarkers in a multicenter setting; (2) elucidation of the patterns and rates of change of imaging and CSF biomarker measurements in control subjects, MCI patients, and AD patients. CSF biomarkers are consistent with disease trajectories predicted by β-amyloid cascade (Hardy, J Alzheimers Dis 2006;9(Suppl 3):151-3) and tau-mediated neurodegeneration hypotheses for AD, whereas brain atrophy and hypometabolism levels show predicted patterns but exhibit differing rates of change depending on region and disease severity; (3) the assessment of alternative methods of diagnostic categorization. Currently, the best classifiers combine optimum features from multiple modalities, including MRI, [(18)F]-fluorodeoxyglucose-PET, CSF biomarkers, and clinical tests; (4) the development of methods for the early detection of AD. CSF biomarkers, β-amyloid 42 and tau, as well as amyloid PET may reflect the earliest steps in AD pathology in mildly symptomatic or even nonsymptomatic subjects, and are leading candidates for the detection of AD in its preclinical stages; (5) the improvement of clinical trial efficiency through the identification of subjects most likely to undergo imminent future clinical decline and the use of more sensitive outcome measures to reduce sample sizes. Baseline cognitive and/or MRI measures generally predicted future decline better than other modalities, whereas MRI measures of change were shown to be the most efficient outcome measures; (6) the confirmation of the AD risk loci CLU, CR1, and PICALM and the identification of novel candidate risk loci; (7) worldwide impact through the establishment of ADNI-like programs in Europe, Asia, and Australia; (8) understanding the biology and pathobiology of normal aging, MCI, and AD through integration of ADNI biomarker data with clinical data from ADNI to stimulate research that will resolve controversies about competing hypotheses on the etiopathogenesis of AD, thereby advancing efforts to find disease-modifying drugs for AD; and (9) the establishment of infrastructure to allow sharing of all raw and processed data without embargo to interested scientific investigators throughout the world. The ADNI study was extended by a 2-year Grand Opportunities grant in 2009 and a renewal of ADNI (ADNI-2) in October 2010 through to 2016, with enrollment of an additional 550 participants.Item Cholinergic Enhancement of Brain Activation in Mild Cognitive Impairment during Episodic Memory Encoding(Frontiers Media, 2013-09-17) Risacher, Shannon L.; Wang, Yang; Wishart, Heather A.; Rabin, Laura A.; Flashman, Laura A.; McDonald, Brenna C.; West, John D.; Santulli, Robert B.; Saykin, Andrew J.; Radiology and Imaging Sciences, School of MedicineObjective: To determine the physiological impact of treatment with donepezil (Aricept) on neural circuitry supporting episodic memory encoding in patients with amnestic mild cognitive impairment (MCI) using functional magnetic resonance imaging (fMRI). Methods: Eighteen patients with MCI and 20 age-matched healthy controls (HC) were scanned twice while performing an event-related verbal episodic encoding task. MCI participants were scanned before treatment and after approximately 3 months on donepezil; HC were untreated but rescanned at the same interval. Voxel-level analyses assessed treatment effects on activation profiles in MCI patients relative to retest changes in non-treated HC. Changes in task-related connectivity in medial temporal circuitry were also evaluated, as were associations between brain activation, task-related functional connectivity, task performance, and clinical measures of cognition. Results: At baseline, the MCI group showed reduced activation during encoding relative to HC in the right medial temporal lobe (MTL; hippocampal/parahippocampal) and additional regions, as well as attenuated task-related deactivation, relative to rest, in a medial parietal lobe cluster. After treatment, the MCI group showed normalized MTL activation and improved parietal deactivation. These changes were associated with cognitive performance. After treatment, the MCI group also demonstrated increased task-related functional connectivity from the right MTL cluster seed region to a network of other sites including the basal nucleus/caudate and bilateral frontal lobes. Increased functional connectivity was associated with improved task performance. Conclusion: Pharmacologic enhancement of cholinergic function in amnestic MCI is associated with changes in brain activation and functional connectivity during episodic memory processing which are in turn related to increased cognitive performance. fMRI is a promising biomarker for assessing treatment related changes in brain function.Item The pattern of atrophy in familial Alzheimer disease: volumetric MRI results from the DIAN study(Wolters Kluwer, 2013) Cash, David M.; Ridgway, Gerard R.; Liang, Yuying; Ryan, Natalie S.; Kinnunen, Kirsi M.; Yeatman, Thomas; Malone, Ian B.; Benzinger, Tammie L. S.; Jack, Clifford R., Jr.; Thompson, Paul M.; Ghetti, Bernardino F.; Saykin, Andrew J.; Masters, Colin L.; Ringman, John M.; Salloway, Stephen P.; Schofield, Peter R.; Sperling, Reisa A.; Cairns, Nigel J.; Marcus, Daniel S.; Xiong, Chengjie; Bateman, Randall J.; Morris, John C.; Rossor, Martin N.; Ourselin, Sébastien; Fox, Nick C.; Dominantly Inherited Alzheimer Network (DIAN); Radiology and Imaging Sciences, School of MedicineObjective: To assess regional patterns of gray and white matter atrophy in familial Alzheimer disease (FAD) mutation carriers. Methods: A total of 192 participants with volumetric T1-weighted MRI, genotyping, and clinical diagnosis were available from the Dominantly Inherited Alzheimer Network. Of these, 69 were presymptomatic mutation carriers, 50 were symptomatic carriers (31 with Clinical Dementia Rating [CDR] = 0.5, 19 with CDR > 0.5), and 73 were noncarriers from the same families. Voxel-based morphometry was used to identify cross-sectional group differences in gray matter and white matter volume. Results: Significant differences in gray matter (p < 0.05, family-wise error-corrected) were observed between noncarriers and mildly symptomatic (CDR = 0.5) carriers in the thalamus and putamen, as well as in the temporal lobe, precuneus, and cingulate gyrus; the same pattern, but with more extensive changes, was seen in those with CDR > 0.5. Significant white matter differences between noncarriers and symptomatic carriers were observed in the cingulum and fornix; these form input and output connections to the medial temporal lobe, cingulate, and precuneus. No differences between noncarriers and presymptomatic carriers survived correction for multiple comparisons, but there was a trend for decreased gray matter in the thalamus for carriers closer to their estimated age at onset. There were no significant increases of gray or white matter in asymptomatic or symptomatic carriers compared to noncarriers. Conclusions: Atrophy in FAD is observed early, both in areas commonly associated with sporadic Alzheimer disease and also in the putamen and thalamus, 2 regions associated with early amyloid deposition in FAD mutation carriers.Item Characterizing the Role of Brain Derived Neurotrophic Factor Genetic Variation in Alzheimer’s Disease Neurodegeneration(Public Library of Science, 2013-09-26) Honea, Robyn A.; Cruchaga, Carlos; Perea, Rodrigo D.; Saykin, Andrew J.; Burns, Jeffrey M.; Weinberger, Daniel R.; Goate, Alison M.; Alzheimer’s Disease Neuroimaging Initiative (ADNI); Radiology and Imaging Sciences, School of MedicineThere is accumulating evidence that neurotrophins, like brain-derived neurotrophic factor (BDNF), may impact aging and Alzheimer's Disease. However, traditional genetic association studies have not found a clear relationship between BDNF and AD. Our goal was to test whether BDNF single nucleotide polymorphisms (SNPs) impact Alzheimer's Disease-related brain imaging and cognitive markers of disease. We completed an imaging genetics study on 645 Alzheimer's Disease Neuroimaging Initiative participants (ND=175, MCI=316, AD=154) who had cognitive, brain imaging, and genetics data at baseline and a subset of those with brain imaging data at two years. Samples were genotyped using the Illumina Human610-Quad BeadChip. 13 SNPs in BDNF were identified in the dataset following quality control measures (rs6265(Val66Met), rs12273363, rs11030094, rs925946, rs1050187, rs2203877, rs11030104, rs11030108, rs10835211, rs7934165, rs908867, rs1491850, rs1157459). We analyzed a subgroup of 8 SNPs that were in low linkage disequilibrium with each other. Automated brain morphometric measures were available through ADNI investigators, and we analyzed baseline cognitive scores, hippocampal and whole brain volumes, and rates of hippocampal and whole brain atrophy and rates of change in the ADAS-Cog over one and two years. Three out of eight BDNF SNPs analyzed were significantly associated with measures of cognitive decline (rs1157659, rs11030094, rs11030108). No SNPs were significantly associated with baseline brain volume measures, however six SNPs were significantly associated with hippocampal and/or whole brain atrophy over two years (rs908867, rs11030094, rs6265, rs10501087, rs1157659, rs1491850). We also found an interaction between the BDNF Val66Met SNP and age with whole brain volume. Our imaging-genetics analysis in a large dataset suggests that while BDNF genetic variation is not specifically associated with a diagnosis of AD, it appears to play a role in AD-related brain neurodegeneration.Item Common folate gene variant, MTHFR C677T, is associated with brain structure in two independent cohorts of people with mild cognitive impairment(Elsevier, 2012-10-04) Rajagopalan, Priya; Jahanshad, Neda; Stein, Jason L.; Hua, Xue; Madsen, Sarah K.; Kohannim, Omid; Hibar, Derrek P.; Toga, Arthur W.; Jack, Clifford R., Jr.; Saykin, Andrew J.; Green, Robert C.; Weiner, Michael W.; Bis, Joshua C.; Kuller, Lewis H.; Riverol, Mario; Becker, James T.; Lopez, Oscar L.; Thompson, Paul M.; Alzheimer's Disease Neuroimaging Initiative (ADNI); Cardiovascular Health Study (CHS); Radiology and Imaging Sciences, School of MedicineA commonly carried C677T polymorphism in a folate-related gene, MTHFR, is associated with higher plasma homocysteine, a well-known mediator of neuronal damage and brain atrophy. As homocysteine promotes brain atrophy, we set out to discover whether people carrying the C677T MTHFR polymorphism which increases homocysteine, might also show systematic differences in brain structure. Using tensor-based morphometry, we tested this association in 359 elderly Caucasian subjects with mild cognitive impairment (MCI) (mean age: 75 ± 7.1 years) scanned with brain MRI and genotyped as part of Alzheimer's Disease Neuroimaging Initiative. We carried out a replication study in an independent, non-overlapping sample of 51 elderly Caucasian subjects with MCI (mean age: 76 ± 5.5 years), scanned with brain MRI and genotyped for MTHFR, as part of the Cardiovascular Health Study. At each voxel in the brain, we tested to see where regional volume differences were associated with carrying one or more MTHFR 'T' alleles. In ADNI subjects, carriers of the MTHFR risk allele had detectable brain volume deficits, in the white matter, of up to 2-8% per risk T allele locally at baseline and showed accelerated brain atrophy of 0.5-1.5% per T allele at 1 year follow-up, after adjusting for age and sex. We replicated these brain volume deficits of up to 5-12% per MTHFR T allele in the independent cohort of CHS subjects. As expected, the associations weakened after controlling for homocysteine levels, which the risk gene affects. The MTHFR risk variant may thus promote brain atrophy by elevating homocysteine levels. This study aims to investigate the spatially detailed effects of this MTHFR polymorphism on brain structure in 3D, pointing to a causal pathway that may promote homocysteine-mediated brain atrophy in elderly people with MCI.Item Thalamic GABA Predicts Fine Motor Performance in Manganese-Exposed Smelter Workers(Public Library of Science, 2014-02-04) Long, Zaiyang; Li, Xiang-Rong; Xu, Jun; Edden, Richard A. E.; Qin, Wei-Ping; Long, Li-Ling; Murdoch, James B.; Zheng, Wei; Jiang, Yue-Ming; Dydak, Ulrike; Radiology and Imaging Sciences, School of MedicineOverexposure to manganese (Mn) may lead to parkinsonian symptoms including motor deficits. The main inhibitory neurotransmitter gamma-aminobutyric acid (GABA) is known to play a pivotal role in the regulation and performance of movement. Therefore this study was aimed at testing the hypothesis that an alteration of GABA following Mn exposure may be associated with fine motor performance in occupationally exposed workers and may underlie the mechanism of Mn-induced motor deficits. A cohort of nine Mn-exposed male smelter workers from an Mn-iron alloy factory and 23 gender- and age-matched controls were recruited and underwent neurological exams, magnetic resonance spectroscopy (MRS) measurements, and Purdue pegboard motor testing. Short-echo-time MRS was used to measure N-Acetyl-aspartate (NAA) and myo-inositol (mI). GABA was detected with a MEGA-PRESS J-editing MRS sequence. The mean thalamic GABA level was significantly increased in smelter workers compared to controls (p = 0.009). Multiple linear regression analysis reveals (1) a significant association between the increase in GABA level and the duration of exposure (R(2) = 0.660, p = 0.039), and (2) significant inverse associations between GABA levels and all Purdue pegboard test scores (for summation of all scores R(2) = 0.902, p = 0.001) in the smelter workers. In addition, levels of mI were reduced significantly in the thalamus and PCC of smelter workers compared to controls (p = 0.030 and p = 0.009, respectively). In conclusion, our results show clear associations between thalamic GABA levels and fine motor performance. Thus in Mn-exposed subjects, increased thalamic GABA levels may serve as a biomarker for subtle deficits in motor control and may become valuable for early diagnosis of Mn poisoning.Item The impact of mindfulness on working memory-related brain activation in breast cancer survivors with cognitive complaints(Springer, 2025) Melis, Michelle; Blommaert, Jeroen; Van der Gucht, Katleen; Smeets, Ann; McDonald, Brenna C.; Sunaert, Stefan; Smith, Andra; Deprez, Sabine; Radiology and Imaging Sciences, School of MedicinePurpose: Cancer-related cognitive impairment (CRCI) has been associated with altered brain activation after chemotherapy in areas related to working memory. Hence, improving working memory capacity and associated brain activation might aid in the recovery of CRCI. In this study, we investigated the potential of a mindfulness-based intervention (MBI) to impact working memory-related brain activation. Methods: Female breast cancer survivors reporting cognitive complaints (N=117) were randomized into a mindfulness (n=43; MBI), physical training (n=36; PT), or waitlist control condition (n=38; WL). Participants completed MRI scans before the intervention, immediately after, and three months post-intervention. Task-based functional MRI was used to measure differences between groups over time in working memory-related brain activation while performing a visual-verbal n-back task. Results: Data of 83 participants (32/26/25 MBI/PT/WL) was included. Compared to the waitlist group, MBI participants showed reduced task-related activation in the right middle frontal and angular gyrus and increased activation in the right dorsal posterior cingulate cortex over time. Compared to the physical training group, MBI participants showed reduced brain activation in the bilateral superior parietal lobule and right dorsal anterior cingulate cortex over time. No differences between physical training and no intervention were identified. Conclusion: This study showed that an 8-week mindfulness-based intervention can significantly alter brain activation across brain regions involved in working memory, attentional control, and emotion processing during performance of a working memory task. This might aid in the recovery of CRCI. Implications for cancer survivors: Mindfulness might alter brain activation patterns while performing a working memory task, which might ultimately aid in restoring higher order cognitive functions.Item Amyloid PET predicts longitudinal functional and cognitive trajectories in a heterogeneous cohort(Wiley, 2025) Younes, Kyan; Johns, Emily; Young, Christina B.; Kennedy, Gabriel; Mukherjee, Shubhabrata; Vossler, Hillary A.; Winer, Joseph; Cody, Karly; Henderson, Victor W.; Poston, Kathleen L.; Betthauser, Tobey J.; Bevis, Bill; Brooks, William M.; Burns, Jeffrey M.; Coombes, Stephen A.; DeCarli, Charles; DiFilippo, Frank P.; Duara, Ranjan; Fan, Audrey P.; Gibbons, Laura E.; Golde, Todd; Johnson, Sterling C.; Lepping, Rebecca J.; Leverenz, James; McDougall, Sean; Rogalski, Emily; Sanders, Elizabeth; Pasaye, Joshua; Sridhar, Jaiashre; Saykin, Andrew J.; Sridharan, Anjali; Swerdlow, Russell; Trittschuh, Emily H.; Vaillancourt, David; Vidoni, Eric; Wang, Wei-En; Mez, Jesse; Hohman, Timothy J.; Tosun, Duygu; Biber, Sarah; Kukull, Walter A.; Crane, Paul K.; Mormino, Elizabeth C.; Radiology and Imaging Sciences, School of MedicineIntroduction: Amyloid positron emission tomography (PET) is increasingly available for diagnosis of Alzheimer`s disease (AD); however, its practical implications in heterogenous cohorts are debated. Methods: Amyloid PET from 890 National Alzheimer`s Coordinating Center participants with up to 10 years post-PET follow up was analyzed. Cox proportional hazards and linear mixed models were used to investigate amyloid burden prediction of etiology and prospective functional status and cognitive decline. Results: Amyloid positivity was associated with progression from unimpaired to mild cognitive impairment and dementia. Amyloid burden in the unimpaired group was associated with lower initial memory levels and faster decline in memory, language, and global cognition. In the Impaired group, amyloid was associated with lower initial levels and faster decline for memory, language, executive function, and global cognition. Discussion: Amyloid burden is an important prognostic marker in a clinically heterogeneous cohort. Future work is needed to establish the proportion of decline driven by AD versus non-AD processes in the context of mixed pathology. Highlights: Our findings highlight the importance of amyloid positron emission tomography (PET) in heterogenous cohorts, including diverse demographics, clinical syndromes, and underlying etiologies. The results also provide evidence that higher amyloid levels were linked to functional progression from unimpaired cognition to mild cognitive impairment (MCI) and from MCI to dementia. In cognitively unimpaired individuals, higher amyloid burden was associated with poorer memory at baseline and subsequent declines in memory, language, and global cognition. Among individuals with cognitive impairment, amyloid burden was associated with worse initial memory, language, executive function, and global cognition, and faster declines over time.Item Novel Mechanical Aspiration Thrombectomy in Patients With Acute Pulmonary Embolism: Results From the Prospective APEX-AV Trial(Elsevier, 2024-12-27) Ranade, Mona; Foster, Malcolm T., III; Brady, Paul S.; Sokol, Seth I.; Butty, Sabah; Klein, Andrew; Maholic, Robert; Safar, Ammar; Patel, Taral; Zlotnick, David; Gans, Daniel; Pollak, Jeffrey; Ferrera, Dean; Stegman, Brian; Basra, Sukhdeep; Moriarty, John; Keeling, Brent; APEX-AV Investigators; Radiology and Imaging Sciences, School of MedicineBackground: There is a need for additional data to assess procedural efficacy and risks associated with mechanical thrombectomy for treating pulmonary embolism (PE) due to its increased utilization and diversity of patient populations presenting with PE. This study evaluated the safety and efficacy of percutaneous mechanical aspiration thrombectomy with the AlphaVac F1885 System (AngioDynamics) in patients with acute intermediate-risk PE. Methods: Patients with acute intermediate-risk PE and a right ventricular (RV)/left ventricular (LV) diameter ratio of ≥0.9 were eligible for enrollment in this prospective, multicenter, single-arm study. The primary effectiveness end point was reduction in the RV/LV ratio at 48 hours. The primary safety end point was the rate of major adverse events (MAEs) defined as subjects who experienced major bleeding, device-related deaths, clinical deterioration, or pulmonary vascular or cardiac injury within 48 hours postprocedurally. Results: In total, 122 subjects were enrolled at 25 sites. Mean procedure time was 37.2 ± 17.7 minutes. There were statistically significant reductions in mean 48-hour postprocedural RV/LV diameter ratio (-0.45 ± 0.27; P < .001). Postprocedural mean pulmonary arterial pressure also significantly declined from 27.8 ± 7.8 mm Hg before the procedure to 21.8 ± 7.2 mm Hg (P < .001). There was a 35.5% mean reduction in clot burden as measured by the modified Miller index score. Five (4.1%) subjects developed 7 MAEs during the postprocedural 48-hour assessment period, the majority of which were access site bleeding. Conclusions: Percutaneous mechanical aspiration thrombectomy with the AlphaVac system provided a safe and effective treatment for acute intermediate-risk PE with a significant reduction in RV/LV ratio and clot burden with a low rate of adverse events.Item Osteopetrosis in the Pediatric Patient: What the Radiologist Needs to Know(Springer, 2024) McLuckey, Morgan N.; Imel, Erik A.; Forbes-Amrhein, Monica M.; Radiology and Imaging Sciences, School of MedicineOsteopetrosis describes several types of rare sclerosing bone dysplasias of varying clinical and radiographic severity. The classic autosomal dominant subtype emerges most often in adolescence but can present from infancy through adulthood. The autosomal recessive osteopetrosis, or "malignant infantile osteopetrosis," presents in infancy with a grimmer prognosis, though the autosomal dominant forms (often mislabeled as "benign") actually can have life-threatening consequences as well. Often osteopetrosis is detected due to skeletal findings on radiographs performed to evaluate injury or as an incidental finding during evaluation for illness. Given the varied phenotypic severity and presentations at different ages, radiologists play an integral role in the care of these patients both in diagnosis and in clinical evaluation and monitoring. A deeper understanding of the underlying genetic basis of the disease can aid in the radiologist in diagnosis and in anticipation of unique complications. An overview of current clinical management is also discussed.