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1.  Comparison of imaging biomarkers in ADNI versus the Mayo Clinic Study of Aging 
Archives of neurology  2012;69(5):614-622.
Objective
To determine whether MRI measurements observed in the Alzheimer's Disease Neuroimaging Initiative (ADNI; convenience-sample) differ from those observed in the Mayo Clinic Study of Aging (MCSA; population-based sample).
Design
Comparison of two samples.
Setting
59 recruiting sites for the ADNI in US/Canada, and the MCSA, a population-based cohort in Olmsted County, MN.
Patients
Cognitively normal (CN) subjects and amnestic mild cognitive impairment (aMCI) subjects were selected from the ADNI convenience cohort and MCSA population-based cohort. Two samples were selected; the first was a simple random sample of subjects from both cohorts in the same age range, and the second applied matching for age, sex, education, apolipoprotein E genotype, and Mini-Mental State Examination.
Main outcome measures
Baseline hippocampal volumes and annual percent decline in hippocampal volume.
Results
In the population-based sample, MCSA subjects were older, less educated, performed worse on MMSE, and less often had family history of AD than ADNI subjects. Baseline hippocampal volumes were larger in ADNI compared to MCSA CN subjects in the random sample, although no differences were observed after matching. Rates of decline in hippocampal volume were greater in ADNI compared to MCSA for both CN and aMCI, even after matching.
Conclusions
Rates of decline in hippocampal volume suggest that ADNI subjects have more aggressive brain pathology than MCSA subjects, and hence may not be representative of the general population. These findings have implications for treatment trials that employ ADNI-like recruitment mechanisms and for studies validating new diagnostic criteria for AD in its various stages.
doi:10.1001/archneurol.2011.3029
PMCID: PMC3569033  PMID: 22782510
2.  Characterization of a Family With c9FTD/ALS Associated With the GGGGCC Repeat Expansion in C9ORF72 
Archives of neurology  2012;69(9):1164-1169.
Background
The hexanucleotide repeat in the chromosome 9 open reading frame 72 (C9ORF72) gene was recently discovered as the pathogenic mechanism underlying many families with frontotemporal dementia (FTD) and/or amyotrophic lateral sclerosis (ALS) linked to chromosome 9 (c9FTD/ALS). We report the clinical, neuropsychological, and neuroimaging findings of a family with the C9ORF72 mutation and clinical diagnoses bridging the FTD, parkinsonism and ALS spectrum.
Objective
To characterize the antemortem characteristics of a family with c9FTD/ALS associated with the GGGGCC repeat expansion in C9ORF72
Design
Clinical series.
Setting
Tertiary care academic medical center.
Patients
The members of the family affected by the mutation with features of FTD and/or ALS.
Main Outcome Measures
Clinical, neuropsychological, and neuroimaging assessments.
Results
All three examined subjects had the hexanucleotide expansion detected in C9ORF72. All had personality/behavioral changes early in the course of the disease. One case had levodopa-unresponsive parkinsonism, and one had ALS. MRI showed symmetric bilateral frontal, temporal, insular and cingulate atrophy.
Conclusions
This report highlights the clinical and neuroimaging characteristics of a family with c9FTD/ALS. Further studies are needed to better understand the phenotypical variability and the clinico-neuroimaging-neuropathologic correlations.
doi:10.1001/archneurol.2012.772
PMCID: PMC3625860  PMID: 22637471
3.  Shapes of the Trajectories of Five Major Biomarkers of Alzheimer’s Disease 
Archives of neurology  2012;69(7):856-867.
Objective
To characterize the shape of the trajectories of Alzheimer’s Disease (AD) biomarkers as a function of MMSE.
Design
Longitudinal registries from the Mayo Clinic and the Alzheimer’s Disease Neuroimaging Initiative (ADNI).
Patients
Two different samples (n=343 and n=598) were created that spanned the cognitive spectrum from normal to AD dementia. Subgroup analyses were performed in members of both cohorts (n=243 and n=328) who were amyloid positive at baseline.
Main Outcome Measures
The shape of biomarker trajectories as a function of MMSE, adjusted for age, was modeled and described as baseline (cross-sectional) and within-subject longitudinal effects. Biomarkers evaluated were cerebro spinal fluid (CSF) Aβ42 and tau; amyloid and fluoro deoxyglucose position emission tomography (PET) imaging, and structural magnetic resonance imaging (MRI).
Results
Baseline biomarker values generally worsened (i.e., non-zero slope) with lower baseline MMSE. Baseline hippocampal volume, amyloid PET and FDG PET values plateaued (i.e., non-linear slope) with lower MMSE in one or more analyses. Longitudinally, within-subject rates of biomarker change were associated with worsening MMSE. Non-constant within-subject rates (deceleration) of biomarker change were found in only one model.
Conclusions
Biomarker trajectory shapes by MMSE were complex and were affected by interactions with age and APOE status. Non-linearity was found in several baseline effects models. Non-constant within-subject rates of biomarker change were found in only one model, likely due to limited within-subject longitudinal follow up. Creating reliable models that describe the full trajectories of AD biomarkers will require significant additional longitudinal data in individual participants.
doi:10.1001/archneurol.2011.3405
PMCID: PMC3595157  PMID: 22409939
Alzheimer’s disease biomarkers; Magnetic Resonance Imaging; cerebro spinal fluid; amyloid PET imaging; FDG PET imaging
4.  Ecology of aging human brain 
Archives of neurology  2011;68(8):1049-1056.
OBJECTIVE
Alzheimer’s disease (AD), cerebral vascular brain injury (VBI), and isocortical Lewy body (LB) disease (LBD) are the major contributors to dementia in community- or population-based studies: Adult Changes in Thought (ACT) study, Honolulu-Asia Aging Study (HAAS), Nun Study (NS), and Oregon Brain Aging Study (OBAS). However, the prevalence of clinically silent forms of these diseases in cognitively normal (CN) adults is less clear.
DESIGN and SETTING
We evaluated 1672 brain autopsies from ACT, HAAS, NS, and OBAS of which 424 met criteria for CN.
MAIN OUTCOME MEASURES
Of these, 336 cases had a comprehensive neuropathologic examination of neuritic plaque (NP) density, Braak stage for neurofibrillary tangles (NFTs), Lewy body (LB) distribution, and number of cerebral microinfarcts (CMIs).
RESULTS
47% of CN cases had moderate or frequent NP density; of these 6% also had Braak stage V or VI for NFTs. 15% of CN cases had medullary LBD; 8% also had nigral and 4% isocortical LBD. The presence of any CMIs was identified in 33% and high level CMIs in 10% of CN individuals. Overall burden of lesions in each individual and their co-morbidity varied widely within each study but were similar among studies.
CONCLUSIONS
These data show an individually varying complex convergence of subclinical diseases in the brain of older CN adults. Appreciating this ecology should help guide future biomarker or neuroimaging studies as well as clinical trials that focus on community- or population-based cohorts.
doi:10.1001/archneurol.2011.157
PMCID: PMC3218566  PMID: 21825242
Alzheimer’s disease; vascular brain injury; Lewy body disease; cognitive aging
5.  Clinical correlates of white matter tract degeneration in PSP 
Archives of Neurology  2011;68(6):753-760.
Objective
Progressive supranuclear palsy (PSP) is associated with degeneration of white matter tracts that can be detected using diffusion tensor imaging (DTI). However, little is known about whether tract degeneration is associated with the clinical symptoms of PSP. The aim of this study was to use DTI to assess white matter tract degeneration in PSP and to investigate correlates, between tract integrity and clinical measures.
Design
Case-control study
Setting
Tertiary care medical centre
Patients
Twenty subjects with probable PSP and 20 age and gender-matched healthy controls. All PSP subjects underwent standardized clinical testing, including the Frontal Behavioral Inventory and Frontal Assessment Battery to assess behavioral change; the PSP Rating Scale to measure disease severity, the Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (parts I, II and III) to measure motor function, and the PSP Saccadic Impairment Scale to measure eye movement abnormalities.
Main outcome measures
Fractional anisotropy and mean diffusivity measured using both region-of-interest analysis and Track Based Spatial Statistics.
Results
Abnormal diffusivity was observed predominantly in superior cerebellar peduncles, body of the corpus callosum, inferior longitudinal fasciculus and superior longitudinal fasciculus in PSP compared to controls. Fractional anisotropy values in the superior cerebellar peduncles correlated with disease severity; inferior longitudinal fasciculus correlated with motor function, and superior longitudinal fasciculus correlated with severity of saccadic impairments.
Conclusions
These results demonstrate that PSP is associated with degeneration of brainstem, association and commissural fibers and that this degeneration likely plays an important role in clinical dysfunction.
doi:10.1001/archneurol.2011.107
PMCID: PMC3401587  PMID: 21670399
6.  Effect of APOE ε4 Status on Intrinsic Network Connectivity in Cognitively Normal Elderly 
Archives of Neurology  2011;68(9):1131-1136.
Objective
To examine default mode and salience network functional connectivity as a function of APOE ε4 status in a group of cognitively normal age, gender and education-matched older adults.
Design
Case-control study.
Setting
Community-based sample
Subjects
Fifty-six cognitively normal APOE ε4 carriers and 56 age, gender and education-matched cognitively normal APOE ε4 non-carriers.
Main Outcome Measure
Alterations in in-phase default mode and salience network connectivity in APOE ε4 carriers compared to APOE ε4 non-carriers ranging from 63 to 91 years of age.
Results
A posterior cingulate seed revealed decreased in-phase connectivity in regions of the posterior default mode network that included the left inferior parietal lobe, left middle temporal gyrus, and bilateral anterior temporal lobes in the ε4 carriers relative to APOE ε4 non-carriers. An anterior cingulate seed showed greater in-phase connectivity in the salience network, including the cingulate gyrus, medial prefrontal cortex, bilateral insular cortex, striatum, and thalamus in APOE ε4 carriers vs. non-carriers. There were no group-wise differences in brain anatomy.
Conclusions
We found reductions in posterior default mode network connectivity but increased salience network connectivity in elderly cognitively normal APOE ε4 carriers relative to APOE ε4 non-carriers at rest. The observation of functional alterations in connectivity in the absence of structural changes between APOE e4 carriers and non-carriers suggests that alterations in connectivity may have the potential to serve as an early biomarker.
doi:10.1001/archneurol.2011.108
PMCID: PMC3392960  PMID: 21555604
7.  Evidence for Ordering of Alzheimer’s Disease Biomarkers 
Archives of Neurology  2011;68(12):1526-1535.
Objective
To empirically assess the concept that Alzheimer’s disease (AD) biomarkers significantly depart from normality in a temporally ordered manner.
Design
Validation sample
Setting
Multi-site, referral centers
Patients
We studied 401 elderly cognitively normal (CN), Mild Cognitive Impairment (MCI) and AD dementia subjects from the Alzheimer’s Disease Neuroimaging Initiative. We compared the proportions of three AD biomarkers – CSF Aβ42, CSF total tau (t-tau), and hippocampal volume adjusted by intra-cranial volume (HVa) - that were abnormal as cognitive impairment worsened. Cut-points demarcating normal vs. abnormal for each biomarker were established by maximizing diagnostic accuracy in independent autopsy samples.
Interventions
None
Main Outcome measures
AD biomarkers
Results
Within each clinical group in the entire sample (n=401) CSF Aβ42 was abnormal more often than t-tau or HVa. Among the 298 subjects with both baseline and 12 month data, the proportion of subjects with abnormal Aβ42 did not change from baseline to 12 months in any group. The proportion of subjects with abnormal t-tau increased from baseline to 12 months in CN (p=0.05) but not in MCI or dementia. In 209 subjects with abnormal CSF AB42 at baseline, the percent abnormal HVa, but not t-tau, increased from baseline to 12 months in MCI.
Conclusions
Reduction in CSF Aβ42 denotes a pathophysiological process that significantly departs from normality (i.e., becomes dynamic) early, while t-tau and HVa are biomarkers of downstream pathophysiological processes. T-tau becomes dynamic before HVa, but HVa is more dynamic in the clinically symptomatic MCI and dementia phases of the disease than t-tau.
doi:10.1001/archneurol.2011.183
PMCID: PMC3387980  PMID: 21825215
Alzheimer’s disease biomarkers; Magnetic Resonance Imaging; CSF tau; CSF Abeta; Alzheimer’s disease staging
8.  Clinical Characterization of a Kindred with a Novel Twelve Octapeptide Repeat Insertion in the Prion Protein Gene 
Archives of Neurology  2011;68(9):1165-1170.
Objective
To report the clinical, electroencephalographic, and neuroradiologic findings in a kindred with a novel insertion in the prion protein gene (PRNP).
Design
Clinical description of a kindred.
Setting
Mayo Clinic Alzheimer’s Disease Research Center (Rochester).
Subjects
Two pathologically-confirmed cases and their relatives.
Main outcome measures
Clinical features, electroencephalographic patterns, magnetic resonance imaging abnormalities, genetic analyses and neuropathological features.
Results
The proband presented with clinical and neuroimaging features of atypical frontotemporal dementia (FTD) and ataxia. Generalized tonic-clonic seizures developed later in her course, and electroencephalography revealed spike and wave discharges but no periodic sharp wave complexes. Her affected sister and father also exhibited FTD-like features, and both experienced generalized tonic-clonic seizures and gait ataxia late in their course. Genetic analyses in the proband identified a novel defect in PRNP with one mutated allele carrying a 288 base pair insertion (BPI) consisting of 12 octapeptide repeats. Neuropathologic examination of the sister and proband revealed PrP-positive plaques and widespread tau-positive tangles.
Conclusion
This kindred has a unique combination of clinical and neuropathologic features associated with the largest BPI identified to date in PRNP, and underscores the need to consider familial prion disease in the differential diagnosis of a familial FTD-like syndrome.
doi:10.1001/archneurol.2011.187
PMCID: PMC3326586  PMID: 21911696
frontotemporal dementia; FTD; nonfluent aphasia; Gerstmann–Straüssler–Scheinker syndrome (GSS); Creutzfeldt-Jakob disease (CJD); prion; PRNP
9.  Longitudinal Changes in White Matter Disease and Cognition in the First Year of the Alzheimer Disease Neuroimaging Initiative 
Archives of neurology  2010;67(11):1370-1378.
Objective
To evaluate relationships between magnetic resonance imaging (MRI)–based measures of white matter hyperintensities (WMHs), measured at baseline and longitudinally, and 1-year cognitive decline using a large convenience sample in a clinical trial design with a relatively mild profile of cardiovascular risk factors.
Design
Convenience sample in a clinical trial design.
Subjects
A total of 804 participants in the Alzheimer Disease Neuroimaging Initiative who received MRI scans, cognitive testing, and clinical evaluations at baseline, 6-month follow-up, and 12-month follow-up visits. For each scan, WMHs were detected automatically on coregistered sets of T1, proton density, and T2 MRI images using a validated method. Mixed-effects regression models evaluated relationships between risk factors for WMHs, WMH volume, and change in outcome measures including Mini-Mental State Examination (MMSE), Alzheimer Disease Assessment Scale–Cognitive Subscale (ADAS-Cog), and Clinical Dementia Rating Scale sum of boxes scores. Covariates in these models included race, sex, years of education, age, apolipoprotein E genotype, baseline clinical diagnosis (cognitively normal, mild cognitive impairment, or Alzheimer disease), cardiovascular risk score, and MRI-based hippocampal and brain volumes.
Results
Higher baseline WMH volume was associated with greater subsequent 1-year increase in ADAS-Cog and decrease in MMSE scores. Greater WMH volume at follow-up was associated with greater ADAS-Cog and lower MMSE scores at follow-up. Higher baseline age and cardiovascular risk score and more impaired baseline clinical diagnosis were associated with higher baseline WMH volume.
Conclusions
White matter hyperintensity volume predicts 1-year cognitive decline in a relatively healthy convenience sample that was similar to clinical trial samples, and therefore should be considered as a covariate of interest at baseline and longitudinally in future AD treatment trials.
doi:10.1001/archneurol.2010.284
PMCID: PMC3082636  PMID: 21060014
10.  Mild Cognitive Impairment: Ten Years Later 
Archives of neurology  2009;66(12):1447-1455.
In the past 10 years, there has been a virtual explosion in the literature concerning the construct of mild cognitive impairment. The interest in this topic demonstrates the increasing emphasis on the identification of the earliest features of cognitive disorders such as Alzheimer’s disease and other dementias. Mild cognitive impairment represents the earliest clinical features of these conditions and, hence, has become a focus of clinical, epidemiological, neuroimaging, biomarker, neuropathological, disease mechanism and clinical trials research. This review summarizes the progress that has been made while also recognizing the challenges that remain.
doi:10.1001/archneurol.2009.266
PMCID: PMC3081688  PMID: 20008648
Mild cognitive impairment; Alzheimer’s disease; Imaging; Cognitive decline
11.  Functional Impact of White Matter Hyperintensities in Cognitively Normal Elderly 
Archives of neurology  2010;67(11):1379-1385.
Objective
To investigate the impact white matter hyperintensities (WMH) detected on MRI have on motor dysfunction and cognitive impairment in non-demented elderly subjects.
Design
Cross-sectional study.
Setting
Population-based study on the incidence and prevalence of cognitive impairment in Olmsted County, MN.
Participants
A total of 148 non-demented elderly (65 males) ranging in age from 73 to 91 years.
Main Outcome Measures
We measured the percentage of the total white matter volume classified as WMH (WMHp) in a priori defined brain regions (i.e. frontal, temporal, parietal, occipital, periventricular or subcortical). Motor impairment was evaluated qualitatively using the Unified Parkinson’s Disease Rating Scale (UPDRS) summary measures of motor skills and quantitatively using a digitized portable walkway system. Four cognitive domains were evaluated using z-scores of memory, language, executive function, and visuospatial reasoning.
Results
A higher WMHp in all regions except occipital was associated with lower executive function z-score (p-value<0.01). A higher WMHp in all regions, but most strongly for parietal lobe, correlated with higher gait/postural-stability/posture UPDRS sum (p-value<0.01). A higher WMHp whether periventricular, subcortical or lobar correlated with reduced velocity (p-value<0.001).
Conclusions
We conclude that executive function is the primary cognitive domain affected by WMH burden. The data suggests that WMH in the parietal lobe are chiefly responsible for reduced balance and postural support compared to the other three lobes and may alter integration of sensory information via parietal lobe dysfunction in the aging brain. It is of interest that parietal WM changes were not the predominant correlate with motor speed, lending evidence to a global involvement of neural networks in gait velocity.
doi:10.1001/archneurol.2010.280
PMCID: PMC3025610  PMID: 21060015
12.  Very Early Semantic Dementia With Progressive Left≫Right Temporal Lobe Atrophy: An Eight-Year Longitudinal Study 
Archives of neurology  2008;65(12):1659-1663.
Background
Semantic dementia (SD) is a syndrome within the spectrum of frontotemporal lobar degenerations (FTLD) characterized by fluent progressive aphasia (particularly anomia) and loss of word meaning.
Objective
To report a unique case of very early semantic dementia with slowly progressive course allowing insights into the early natural history of this disorder.
Design
Case report.
Setting
Tertiary care university hospital and academic center.
Patient
A 62-year-old female retired teacher presenting with “memory” complaints.
Main Outcome Measures
Clinical course, neuropsychological data, MRI.
Results
The patient was first evaluated when standard neuropsychological measures were normal, but subtle left anterior temporal lobe atrophy was present. Over the follow-up period of eight years, she developed profound anomia and loss of word meaning associated with progressive left anterior temporal lobe atrophy consistent with semantic dementia. In more recent years, anterograde memory impairment as well as mild prosopagnosia have evolved in association with left hippocampal atrophy and subtle atrophy in the homologous gyri of the right anterior temporal lobe. She remains functionally independent despite her current deficits.
Conclusions
Early identification of patients who will develop semantic dementia is difficult and might be missed with standard clinical, neuropsychological, and structural neuroimaging evaluations. Recognition of this relatively rare syndrome is important for early diagnosis and prognostication, and particularly for therapeutic interventions in the future.
doi:10.1001/archneurol.2008.507
PMCID: PMC2902001  PMID: 19064755
frontotemporal lobar degeneration; semantic dementia; MRI; neuropsychology
13.  Genomic Susceptibility Loci for Brain Atrophy, Ventricular Volume, and Leukoaraiosis in Hypertensive Sibships 
Archives of neurology  2009;66(7):847-857.
Objective
To localize susceptibility genes for alterations in brain structure associated with risk of stroke and dementia. We conducted genomewide linkage analyses for magnetic resonance imaging (MRI) measures of brain atrophy, ventricular, and subcortical white matter hyperintensity (leukoaraiosis) in 689 non-Hispanic white (673 sibling pairs; median age, 61 years) and 544 non-Hispanic black participants (503 sibling pairs; median age, 64 years) from sibships with at least 2 members with essential hypertension.
Design, Setting, and Patients
We determined brain, ventricular, and leukoaraiosis volumes from axial fluid-attenuated inversion recovery MRI; we calculated brain atrophy as the difference between total intracranial and brain volumes. Microsatellite markers (n=451) distributed across the 22 autosomes were genotyped, and we used variance components methods to estimate heritability and assess evidence of genetic linkage for each MRI measure.
Main Outcome Measures
Brain atrophy ventricular volume, and leukoaraiosis determined from fluid-attenuated inversion recovery MRI.
Results
In both races, the heritability of each MRI measure was statistically greater than 0 (P< .001), ranging in magnitude from 0.42 (for ventricular volume in blacks) to 0.69 (for brain atrophy in blacks). Based on multipoint logarithm of odds scores (MLS), the strongest evidence of genetic linkage was observed for brain atrophy on chromosomes 1 (MLS, 3.49 at 161 cM; P< .001) and 17 (MLS, 3.08 at 18 cM; P< .001) in whites; for ventricular volume on chromosome 12 (MLS, 3.67 at 49 cM; P< .001) in blacks and chromosome 10 (MLS, 2.47 at 110 cM; P < .001) in whites; and for leukoaraiosis on chromosome 11 (MLS, 2.21 at 118 cM; P < .001) in whites and chromosome 22 (MLS, 2.02 at 36 cM; P= .001) in blacks.
Conclusions
The MRI measures of structural brain injury are heritable in non-Hispanic black and white sibships ascertained through hypertensive sibling pairs. The susceptibility loci for brain atrophy, ventricular volume, and leukoaraiosis identified by linkage analyses differ among MRI measures and between races.
doi:10.1001/archneurol.2009.110
PMCID: PMC2828902  PMID: 19597086
14.  Voxel-based morphometry in frontotemporal lobar degeneration with ubiquitin-positive inclusions with and without progranulin mutations 
Archives of neurology  2007;64(3):371-376.
Background
Mutations in the progranulin gene (PGRN) have recently been identified as a cause of frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U) in some families.
Objective
To determine whether there is a difference in the patterns of atrophy in cases with FTLD-U with and without a mutation in PGRN.
Design
Case control study
Setting
Brain bank of a tertiary care medical center
Patients
All subjects that had screened positive for mutations in PGRN and had a volumetric MRI were identified (n=8, PGRN (+)). Subjects were then matched by clinical diagnosis to a group of eight subjects with a pathological diagnosis of FTLD-U that had screened negative for mutations in PGRN (PGRN (−)). All subjects were then age and gender-matched to a control subject.
Main outcome Measures
Voxel-based morphometry was used to assess the patterns of grey matter atrophy in the PGRN (+) and (−) groups compared to controls, and compared to each other.
Results
The PGRN (+) group showed a widespread and severe pattern of grey matter loss predominantly affecting the frontal, temporal and parietal lobes. In comparison, the PGRN (−) group showed a less severe pattern of loss restricted mainly to the temporal and frontal lobes. On direct comparison the PGRN (+) group showed greater loss in the frontal and parietal lobes compared to the PGRN (−) group.
Conclusions
This study suggests that PGRN mutations may be associated with a specific and severe pattern of cerebral atrophy in subjects with FTLD-U.
doi:10.1001/archneur.64.3.371
PMCID: PMC2752412  PMID: 17353379
Frontotemporal dementia; Voxel-based morphometry; Ubiquitin; Dentate; Progranulin
15.  Visual Hallucinations in Posterior Cortical Atrophy 
Archives of neurology  2006;63(10):1427-1432.
Objective
To compare clinical and imaging features of patients with posterior cortical atrophy (PCA) with and without well-formed visual hallucinations.
Setting
Tertiary care medical center
Methods
Fifty-nine patients fulfilling criteria for PCA were retrospectively identified, and divided into two groups based on the presence (N=13) and absence (N=46) of visual hallucinations. Both groups were then compared statistically for clinical differences, as well as with voxel-based morphometry (VBM) for imaging differences.
Results
In PCA patients with hallucinations, parkinsonism and rapid eye movement sleep behavior disorder occurred more frequently (p<0.0001), as did myoclonic jerks (p=0.0002). VBM analysis showed greater atrophy in a network of structures, including the primary visual cortex, lentiform nuclei, thalamus, basal forebrain and midbrain in the patients with hallucinations.
Conclusions
Hallucinations in patients with PCA are associated with parkinsonism, rapid eye movement sleep behavior disorder, and myoclonic jerks. The results from the VBM analysis suggest that hallucinations in PCA cannot be exclusively attributed to atrophy of the posterior association cortices and may involve a circuit of thalamocortical connections.
doi:10.1001/archneur.63.10.1427
PMCID: PMC2748870  PMID: 17030659
Parkinsonism; Thalamus; Myoclonic jerks; REM sleep; Voxel based morphometry
16.  Hippocampal Volumes, Proton Magnetic Resonance Spectroscopy Metabolites, and Cerebrovascular Disease in Mild Cognitive Impairment Subtypes 
Archives of neurology  2008;65(12):1621-1628.
Background
Although a majority of patients with amnestic mild cognitive impairment (aMCI) progress to Alzheimer disease, the natural history of nonamnestic MCI (naMCI) is less clear. Noninvasive imaging surrogates for underlying pathological findings in MCI would be clinically useful for identifying patients who may benefit from disease-specific treatments at the prodromal stage of dementia.
Objective
To determine the characteristic magnetic resonance imaging (MRI) and proton MR spectroscopy (1H MRS) profiles of MCI subtypes.
Design
Case-control study.
Setting
Community-based sample at a tertiary referral center.
Patients
Ninety-one patients with single-domain aMCI, 32 patients with multiple-domain aMCI, 20 patients with single- or multiple-domain naMCI, and 100 cognitively normal elderly subjects frequency-matched by age and sex.
Main Outcome Measures
Posterior cingulate gyrus 1H MRS metabolite ratios, hippocampal volumes, and cerebrovascular disease on MRI.
Results
Patients with single-domain aMCI were characterized by small hippocampal volumes and elevated ratios of myo-inositol to creatine levels. Patients with naMCI on average had normal hippocampal volumes and 1H MRS metabolite ratios, but a greater proportion (3 of 20 patients [15%]) had cortical infarctions compared with patients with single-domain aMCI (6 of 91 [7%]). For characterization of MCI subtypes, 1H MRS and structural MRI findings were complementary.
Conclusions
The MRI and 1H MRS findings in singledomain aMCI are consistent with a pattern similar to that of Alzheimer disease. Absence of this pattern on average in patients with naMCI suggests that cerebrovascular disease and other neurodegenerative diseases may be contributing to the cognitive impairment in many individuals with naMCI.
doi:10.1001/archneur.65.12.1621
PMCID: PMC2743393  PMID: 19064749

Results 1-16 (16)