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Crossed cerebellar diaschisis (CCD) is defined as amatched hypoperfusion and hypometabolism inthe cerebellar hemisphere contralateral to a supra-tentorial lesion (1). CCD was first reported byBaron et al. (2) in stroke patients in 1980 usingpositron emission tomography (PET). Since then,studies conducted with single-photon emissioncomputed tomography (SPECT) or with PEThave confirmed this phenomenon to be associatedwith stroke as well as other conditions, such asischemia, tumor, epilepsy, hemorrhage and arte-riovenous malformations (3). Evidence suggeststhat CCD most likely results from disease-relatedloss of remote stimulation and consequent neuraldegeneration (3–6). However, in some patients,CCD is a reversible phenomenon (7, 8).Diffusion-weighted magnetic resonance imaging(DWI) is a feasible method to evaluate waterdiffusion in biochemical system. In DWI, threegradient-directions are applied, sufficient to esti-mate the trace of the diffusion tensor or averagediffusivity, a putative measure of edema. Theapparent diffusion coefficient (ADC) is calculatedfrom the DWIs. ADC measures the magnitude ofdiffusion (of water molecules) within cerebraltissue. A low value for ADC indicates that thecortical white matter tracts are organized, whereasa high value for ADC indicates that these tracts aredisorganized. Changes in ADC have been recordedin the cytotoxic (9) and vasogenic oedema (10), andimpaired neurofilament alignment and damage ofthe myelin sheath (11). A recent study proposedthat the changes of diffusion characterizes can beused to track transsynaptic degeneration of middle

The purposes of the present study were to compare the flow defect volumes on perfusion-weighted magnetic resonance imaging (PWI) and 99mTc-labeled ethylcysteinate dimer (99mTc-ECD) single photon emission computed tomography (SPECT) at acute and subacute stages of ischemic stroke and to analyze the relationship between the detected flow defects on the two methods and neurological status and clinical outcomes. Perfusion defects on PWI and SPECT were measured within 48 h and on day 8 of the onset of stroke from 22 patients with their first-ever acute supratentorial ischemic stroke. The primary neurological status was evaluated prior to the imaging. Clinical outcome was assessed at 3 months after the onset of the stroke. The volumes of cerebral blood flow (CBF) defects did not differ between SPECT and PWI within the 48-h examinations. However, the volume of CBF defect was significantly larger on SPECT than on PWI on day 8 (p = 0.03). Within the 48-h examinations, the CBF defect volumes on SPECT and PWI were comparably related to the neurological status. On day 8, the CBF defect volume on SPECT showed higher correlation to the neurological status and more precisely predicted the clinical outcomes at 3 months than PWI. 99mTC-ECD-SPECT and PWI both have ability to detect cerebral hypoperfusion in patients with ischemic stroke but with some differences. The value of SPECT is more accurate in terms of the delayed outcome, such as prognosis and rehabilitation planning.

Most violent crimes in Western societies are committed by a small group of men who display antisocial behavior from an early age that remains stable across the life-span. It is not known if these men display abnormal brain structure. We compared regional brain volumes of 26 persistently violent offenders with antisocial personality disorder and substance dependence and 25 healthy men using magnetic resonance imaging volumetry and voxel-based morphometry (VBM). The violent offenders, as compared with the healthy men, had markedly larger white matter volumes, bilaterally, in the occipital and parietal lobes, and in the left cerebellum, and larger grey matter volume in right cerebellum (effect sizes up to 1.24, P

A protocol for quantitative 1H NMR analysis of human cerebrospinal fluid (hCSF) was built up and assessed as based on Constrained Total-Line-Shape (CTLS) fitting. In this method, linear constraints were applied to spectral structures. The 1H NMR spectra of 45 human CSF samples were measured and quantified using the CTLS method. The quantification strategies based on total-line-shape fitting are discussed. The metabolic model for CTLS includes 31 metabolites covering 85% of the total spectral intensity, excluding the protein contribution. Prior to data analysis, the data was divided into patients with no Alzheimer’s disease (AD), but with a normal AD marker profile (the peptide β-amyloid42 and tau protein) present in CSF, and into controls that do not have an AD marker profile in CSF. Unexpectedly large variations in metabolite concentrations within the two patient groups were detected, but an analysis of variance revealed a significant (P = 0.027) difference only in the concentration of creatinine which was higher in patients that had a normal AD marker profile. Multivariate classification tools such as self-organizing maps (SOM) failed in separation of the two classes.

Objectives We set to investigate the possible role of genes and environment in developing Alzheimer's disease (AD) in monozygotic twin pairs discordant for AD. Methods Three pairs of twins discordant for AD, who were enrolled in the Finnish Twin Cohort, were used in the study and compared with 13 controls. Gray matter changes were assessed with magnetic resonance images using voxel-based morphometry with statistical parametric mapping. Results In the affected twins, the peaks of volume loss were located bilaterally in the temporal (including the hippocampus), the frontal, and the parietal lobes, while in the unaffected siblings, the peaks were located in the frontal gyri and in the parietal lobule. Thus, in the unaffected twins, the pattern of volume loss overlaps with the neocortical but not with the medial temporal areas. Discussion These findings suggest that genetic factors more largely control neocortical regions, whereas environmental factors more strongly affect medial temporal regions.

Objective To test whether the information obtained from cerebrospinal fluid (CSF) and analysed with high-field proton ( 1 H) MR spectroscopy (MRS) would help the diagnosis of most common forms of dementia. Setting A total of 31 metabolites from CSF from 222 controls and patients suffering from various dementias (Alzheimer’s disease (AD), vascular dementia, Lewy body disease (LBD) and frontotemporal dementia (FTD)) were quantified using 1 H MRS. Main outcome measure Clinical diagnosis. Results AD was classified with an accuracy of 85.5%. For a group of very early stage patients with AD, the result was significantly higher, 92.3%. Vascular dementia, LBD and FTD were all diagnosed with 100% accuracy in controls and from AD with an accuracy ranging between 85.5% and 93.4%. Conclusions The results indicate that the composition of CSF contains enough information of the neurological state of a given patient with a given dementia to be diagnosed with extremely high accuracy. This approach might provide potentially a very powerful diagnostic tool to help the diagnostic process of dementias.

Objectives We examined whether the apolipoprotein E (ApoE) allele epsilon4 influences imaging findings in stroke as assessed by diffusion- (DWI) and perfusion-weighted (PWI) magnetic resonance imaging, and MR angiography (MRA). Methods Eight ApoE epsilon4 carriers and 15 non-carriers with acute ischemic stroke in the anterior circulation underwent DWI, PWI, and MRA within 24 h of stroke. DWI and PWI were repeated a week later. The apparent diffusion coefficient, relative cerebral volume (rCBV), relative cerebral blood flow (rCBF) and relative mean transit time were measured in three subregions on day one. Results In the ischemic core and the area of infarct growth, rCBV values were significantly higher in the epsilon4 carriers compared with the non-carriers. Based on the MRA findings, collateral blood flow was better in the epsilon4 carriers than in the non-carriers. Under the comparable severity of hypoperfusion, the hypoperfused area proceeded to infarction later or did not proceed to infarction at all in the non-carriers. Conclusion These preliminary data suggest that in the ApoE allele epsilon4 carriers the threshold for the brain tissue to survive hypoperfusion versus to proceed to infarction seems to be different from that of the non-carriers.

Background and aims: To test the agreement of a visual rating scale of medial temporal lobe atrophy (MTA) with linear and volumetric assessments, and to test its accuracy in discriminating between Alzheimer’s disease (AD) patients and controls. Methods: Participants were 28 patients with AD and 29 healthy controls. MTA was evaluated according to Scheltens’ five-point scale. Its accuracy in distinguishing AD patients from controls was evaluated as a stand-alone measure and in association with linear [width of the temporal horn (WTH)] and volumetric [hippocampal volume (HV)] measures. Results: The agreement of this visual rating scale with the other MTA measures was statistically significant (vs WTH and vs HV, p for trend

Background: Mild cognitive impairment (MCI) is the most widely used concept in classifying cognitive impairment in the elderly who do not fulfil the criteria for dementia. MCI is considered to confer an increased risk of progressing to dementia and most often Alzheimer's disease (AD). Various approaches such as imaging of the brain have been applied to predict the conversion of MCI to dementia. A number of volumetric magnetic resonance imaging (MRI) studies have detected atrophy of the medial temporal lobe in subjects with MCI, but for the other cerebral regions the results have been inconsistent. Objective: To study the pattern of brain atrophy in MCI. Methods: Thirty two controls and 51 individuals with MCI deriving from population based cohorts were studied by MRI using voxel based morphometry. The threshold of t maps was set at p

Some brain structures atrophic in frontotemporal dementia (FTD) belong to the rostral limbic system (RLS), that regulates context-dependent behaviors after evaluation of the motivational content of stimuli. The clinical manifestations of FTD are consistent with its impairment. Aim of this study was to assess whole brain morphology in FTD using magnetic resonance imaging (MRI) and voxel-based morphometry with statistic parametric mapping (SPM99) to test the hypothesis that the RLS might be specifically targeted by FTD. Nine FTD patients and 26 healthy controls underwent high resolution 3D MRI. SPM99 performed (a) spatial normalization to a customized template, (b) segmentation, (c) smoothing, (d) voxel-by-voxel comparison of gray matter between cases and controls. P was set at 0.05 corrected for multiple comparisons. All but one regions of the RLS (the periaqueductal gray) were atrophic in FTD. At P

Magnetic resonance imaging (MRI) has been suggested as a useful tool in early diagnosis of Alzheimer's disease (AD). Based on MRI-derived volumes, we studied the hippocampus and entorhinal cortex (ERC) in 59 controls, 65 individuals with mild cognitive impairment (MCI) and 48 patients with AD. The controls and individuals with MCI were derived from population-based cohorts. Volumes of the hippocampus and ERC were significantly reduced in the following order: control > MCI > AD. Stepwise discriminant function analysis showed that the most efficient overall classification between controls and individuals with MCI subjects was achieved with ERC measurements (65.9%). However, the best overall classification between controls and AD patients (90.7%), and between individuals with MCI and AD patients (82.3%) was achieved with hippocampal volumes. Our results suggest that the ERC atrophy precedes hippocampal atrophy in AD. The ERC volume loss is dominant over the hippocampal volume loss in MCI, whereas more pronounced hippocampal volume loss appears in mild AD.

This study aimed to investigate whether there are differences in serum testosterone levels between male patients with Alzheimer's disease (AD) and cognitively normal male controls. Testosterone and sex hormone binding globulin (SHBG) levels were measured from 14 patients with mild to moderate AD and 16 age-matched control males. The AD patients had higher levels of serum total (P = 0.02) and free testosterone (P < 0.001), and higher free androgen index (FAI) (P = 0.02) compared to controls. No differences were found for the SHBG levels. These data provide no support for hypotheses of (disproportionally) decreased levels of serum testosterone in AD. These data also show that all cognitively normal controls had an FAI below the normal range.

Apolipoprotein E (ApoE) genotype has been shown to influence results in neuroimaging studies using a number of various imaging modalities. No in vivo data exists on whether or not there are ApoE-related changes observable by proton magnetic resonance spectroscopy (MRS). In this study we measured absolute peak areas of proton MR spectra obtained from the occipital cortex in 22 non-demented elderly with (n = 8) or without (n = 14) the ApoE epsilon4 allele. No statistically significant differences were found in levels of N-acetyl aspartate, myo-inositol, or choline containing compounds between the groups. Instead, compared with the non-carriers, the levels of creatine were significantly lower in the epsilon4 carriers, suggesting increased metabolic demands in the brain of the epsilon4 carriers. The levels of creatine also correlated significantly with age and performance on the Mini-Mental State Examination test in the epsilon4 carriers, but not in the non-carriers. These findings may be of significant clinical interest as potential indicator of incipient AD, and also from therapeutical point of view given the potential neuroprotective effects of creatine.

Objective: To compare patterns of brain atrophy in fronto-temporal dementia (FTD) and Alzheimer’s disease (AD) since atrophy in individual areas may not be sufficiently specific as diagnostic marker. Methods: Frontal, temporal and hippocampal atrophy was measured from MRI of 10 FTD patients, 27 AD, and 27 controls. Corrected atrophy and asymmetry were computed (W-scores). Results: FTD had mild atrophy in the hippocampus (average W-score =− 1.3), severe in the frontal (W-score =− 2.4) and very severe in the temporal lobes (W-score =− 2.9). AD had moderate atrophy in the hippocampus and temporal lobes (W-score =− 1.8 and −1.9, respectively), and very mild frontal atrophy (W-score =− 0.9). Atrophy was more asymmetrical in FTD (left more atrophic) than in AD patients, particularly in the temporal lobes. A discriminant function including the asymmetry values of frontal and temporal regions could separate FTD from AD with 90% sensitivity and 93% specificity. Conclusions: FTD is characterized by a specific pattern of atrophy, more useful than atrophy of single regions in the differential diagnosis. © 2002 Elsevier Science Inc. All rights reserved.

Objectives: To test the applicability of an automated method of magnetic resonance image analysis (voxel based morphometry) to detect presence and severity of regional grey matter density reduction—a proxy of atrophy—in Alzheimer's disease. Methods: Twenty nine probable Alzheimer's patients and 26 non-demented controls (mini-mental state examinations mean (SD) 21 (4) and 29 (1)) underwent high resolution 3D brain magnetic resonance imaging. Spatial normalisation to a stereotactic template, segmentation into grey matter, white matter, and cerebrospinal fluid, and smoothing of the grey matter were carried out based on statistical parametric mapping (SPM99) algorithms. Analyses were carried out: (a) contrasting all Alzheimer's patients with all controls (p

Crude and corrected amygdaloid volumes were computed from magnetic resonance scans in ten patients with frontotemporal dementia (FTD), 25 patients with Alzheimer's disease (AD) and 27 controls. Amygdaloid atrophy was present in FTD (P

Diffusion- and perfusion-weighted magnetic resonance imaging (MRI) was used to study the putative effects of apolipoprotein E (ApoE) polymorphism in stroke. Thirty-one patients with acute stroke, comparative for age and gender were scanned, nine of whom were ApoE allele epsilon 4 carriers. Initially, less than 24 hours from the onset of stroke, the epsilon 4 carriers had significantly smaller volumes of hypoperfusion on relative cerebral blood volume map (P = 0.001), and smaller infarct volumes (P = 0.008) compared with the noncarriers. By day 8, this difference in the infarct volumes had disappeared, suggesting relatively enhanced infarct growth. On average, the total infarct volume increased 145% of the initial infarct volume in the epsilon 4 carriers, and 84% in the noncarriers. There were strong correlations between the imaging findings and clinical status initially and with the outcome 3 months after the stroke in the epsilon 4 noncarriers, but, with a single exception at acute phase, a lack thereof in the epsilon 4 carriers. These patterns were virtually similar in a subgroup of patients with middle cerebral artery stroke. These data support the hypothesis of increased general vulnerability of the brain in the epsilon 4 carriers. Thus, the effects of ApoE polymorphism should be accounted for when interpreting diffusion- and perfusion-weighted MRI studies, particularly if predicting lesion growth.

The purpose of this review is to explore and summarize recent advances in the structural imaging of cognitive impairment and the dementias. The focus is practical, covering issues that bear relevance to clinical practice or diagnosis. Findings in mild cognitive impairment, a state preceding but not necessarily leading to dementia, are discussed. Data from dementias other than Alzheimer's disease are reviewed at some length before outlining some novel issues in Alzheimer's disease imaging.A number of studies have proposed some medial temporal atrophy in mild cognitive impairment, and this may have some clinical value in predicting conversion to dementia. Data on other regions have also been proposed to predict conversion, but a number of studies on these regions have yielded entirely conflicting results. Data are also accumulating on the medial temporal lobe and other regions in non-Alzheimer's dementias.The medial temporal lobe is still the region of interest when studying mild cognitive impairment and Alzheimer's disease. Medial temporal atrophy, or lack thereof, may be of some diagnostic value even in non-Alzheimer's dementias. Medial temporal atrophy, however, is not an Alzheimer's disease-specific feature. One potential approach to improve the radiological diagnosis of dementia is mapping a number of regions in order to define patterns of atrophy. At present, however, the scarcity of existing data prevents unambiguous conclusions on this issue.

This paper focuses on hypertension and hypercholesterolaemia as risk factors for Alzheimer's disease and, as such, subjects for prevention. The long-term, prospective, population-based studies regarding the relationship between hypertension or hypercholesterolaemia and Alzheimer's disease, and the clinical studies regarding the association between antihypertensive or lipid-lowering medications and the risk of Alzheimer's disease, are reviewed. These studies provide evidence to suggest that elevated blood pressure and cholesterol levels earlier in life may have an important role in the development and expression of late-life Alzheimer's disease. Based on these data, we propose that proper, early interventions aimed at reducing these cardiovascular risk factors may have an impact on the future incidence and prevalence of Alzheimer's disease.

Verbal fluency tests (VFTs) are suggested to assess frontal lobe function. This view is supported by functional imaging studies that report left frontal activation during VFTs. VFTs require retrieval of semantically associated words from long-term memory storage. The neural networks that participate in this process, however, are largely unknown. These neural networks are of interest, given that patients with early Alzheimer's disease, typically without frontal pathology, are often impaired in VFTs. In the present study, functional magnetic resonance imaging was performed to determine brain activation areas during VFTs in young subjects. In the activation task, category fluency was contrasted with orderly listing of numbers. As judged from using this comparison, there was activation in the left medial temporal lobe, in the inferior frontal and retrosplenial cortices bilaterally, and in the left superior parietal lobule. Left medial temporal lobe activation was present in 13 of the 14 study subjects either in the hippocampal formation (11 of 14) or in the posterior parahippocampal gyrus (12 of 14). These results suggest that the medial temporal lobe is required for the process of retrieval by category. Functional magnetic resonance imaging combined with a category fluency task may provide a new method to study patients with early Alzheimer's disease.

Background: Due to the progressive nature of Alzheimer’s disease (AD), it has been proposed that serial imaging studies tracking the course of progression might improve the diagnostic accuracy of AD. Methods: Longitudinal changes in hippocampal volumes were evaluated using magnetic resonance imaging (MRI) over a period of 3 years in 27 AD patients and 8 control subjects. Results: A statistically nonsignificant trend towards accelerated volume loss in the AD group compared to control subjects was observed. During the study period, the average shrinkage of the hippocampal volume ranged from −2.2% to −5.8% in control subjects, and from −2.3% to −15.6% in AD patients. Conclusions: The observed changes at an individual level were small, and within the accuracy range of the measurements. Therefore, serial MRI of the hippocampus did not offer any advantage over a single MRI to support the diagnosis of AD in this study sample.

Asymmetry of brain structures is common to many species and is even present in utero. Some developmental, pathological, and dementing diseases are associated with alterations in normal anatomical asymmetries. Anatomical asymmetries, however, have been only superficially studied in Alzheimer's disease. Recent evidence indicates that the allele epsilon4 of the apolipoprotein E (ApoE), a well known risk factor for Alzheimer's disease, might play a part in determining some brain morphological changes both in normal carriers and in patients with Alzheimer's disease. This study evaluated the effect of the ApoE genotype on hippocampal asymmetry in patients with Alzheimer's disease carrying 0, 1, and 2 copies of the allele. Volumetric right-left differences of the hippocampi were computed in 28 right handed patients with Alzheimer's disease (14 -/-, 9 epsilon4/-, and 5 epsilon4/4) and 30 controls without detectable cognitive deficit. In controls, the right hippocampus was larger than the left, whereas in patients with Alzheimer's disease this asymmetry was progressively reduced with increasing gene dose of the epsilon4 allele, and the asymmetry was reversed in the epsilon4/4 Alzheimer's disease group. The mean right-left volume differences were: 1.2, 0.7, 0.2, and -1.0 in controls, -/-, epsilon4/-, and epsilon4/4 patients, respectively (sex adjusted p for trend=0.017). The data indicate a dose dependent effect of the ApoE epsilon4 allele on hippocampal volume asymmetry in Alzheimer's disease.

We investigated the effect of the alpha2-agonist, clonidine (orally: 0.5 and 2 microg/kg), administration on parameters assessing attention and short-term recognition memory in Alzheimer's disease patients. Clonidine 2 microg/kg, but not 0.5 microg/kg, disrupted memory accuracy in delayed matching to sample test delay-dependently in nine out of 28 patients. The volumes of the hippocampus and the entorhinal cortex of those Alzheimer's disease patients who were sensitive to clonidine administration were larger than those whose performance was unaffected by clonidine. These two groups of Alzheimer's disease patients performed equally in measures of attention after placebo or clonidine administration. Clonidine 2 microg/kg disrupted attention only at levels of testing that were demanding for the individual patients. Our results suggest that the disruptive effect of clonidine on short-term memory in Alzheimer's disease patients may be mediated via the hippocampus and the entorhinal cortex. Furthermore, the deleterious effect of clonidine on effortful attention is mediated via different brain systems from those involved in the modulation of memory function.

We measured the volumes of the entorhinal, perirhinal, and temporopolar cortices on magnetic resonance images by using a recently designed histology-based protocol in 30 patients with early Alzheimer's disease (AD) and 32 healthy control subjects. Compared to the controls, all of these cortical regions were significantly atrophied in AD patients (p < 0.0001). However, the entorhinal cortex was the most severely involved brain region studied, with 40% volume loss, and this region provided the highest discriminative accuracy (92%) in separating patients with AD from healthy control subjects. Importantly, the entorhinal volume loss was evident already in mild AD. In addition, the volume of the entorhinal cortex was not dependent on age, but it did correlate significantly with the severity of the disease. Because it assesses the major site of initial neuropathological changes in AD, magnetic resonance imaging volumetric measurement of the entorhinal cortex can offer a tool for distinguishing AD patients even in the very early stages of the disease from healthy aged subjects.

In this study, magnetic resonance imaging (MRI) of the hippocampus for the diagnosis of early Alzheimer's disease (AD) is evaluated. We measured hippocampal volumes and the area of the medial hippocampus with a 1.5 T MR imager in 160 subjects: 55 patients with probable AD according to the NINCDS-ADRDA criteria, 43 subjects fulfilling the NIMH criteria of age-associated memory impairment (AAMI), 42 cognitively normal elderly controls, and 20 controls younger than 50 years. Three methods for normalization were compared. The hippocampi were atrophied in the AD patients, but not in the AAMI subjects or the elderly controls. There was no significant correlation between hippocampal volumes and age in the nondemented subjects. The discrimination based on volumetry resulted in an overall correct classification of 92% of AD patients vs. nondemented elderly subjects, whereas discrimination based on hippocampal area was less accurate, producing a correct classification in 80% of the subjects. We conclude that the hippocampus as assessed by MRI volumetry is atrophied early in AD, and spared by aging or AAMI. A brief critical review of previous studies is in concordance with the presented data: all the previous studies that have used volumetry, have similarly ended up with a good classification, whereas simpler or subjective measurements, subject to various sources of bias, have produced most variable results.

SummaryThe presence of cavum septum pellucidum (CSP) has been reported to be a neurodevelopmental marker of psychopathy. We scanned 26 violent offenders and 25 controls; 2 offenders and 2 controls had CSP (8% in both groups). Thus, the presence of CSP is not a common or a unique feature of antisocial personality disorder or psychopathy.

A prolonged MR T 2 relaxation time was proposed to mark the presence and severity of Alzheimer's disease (AD). We studied the value of T 2 relaxometry in diagnosing early AD. T 2 was measured from 54 patients with AD, 25 subjects with age-associated memory impairment (AAMI), 18 elderly and 16 young controls. The AD patients had longer T 2 in the right hippocampal head (104 ± 11 ms) and tail (98 ± 10 ms) than age-matched controls (95 ± 5 and 92 ± 9 ms, respectively). This prolongation was not related to age. In the AD group, the T 2 of the left hippocampal head also correlated with the clinical severity. The T 2 of the amygdala did not differ across the groups. Increased T 2 in the temporal and parietal white matter and the thalamus related to increasing age rather than to the diagnostic category. The AAMI subjects had T 2 comparable with those of age-matched controls. Despite the prolongation of T 2 in the AD group the possible diagnostic value was compromized by a substantial overlap between the study groups. We, thus, conclude that the T 2 relaxometry is not a reliable method for diagnosing early AD.

Hippocampal atrophy detected by volumetric MRI is a sensitive feature of early Alzheimer's disease (AD), but there are no studies evaluating hippocampal atrophy by MR volumetry in other dementing diseases. We therefore compared hippocampal volumes in a total of 113 subjects: 50 patients with mild to moderate AD, 9 patients with vascular dementia (VaD), 12 patients with idiopathic Parkinson's disease (PD) without dementia, 8 patients with PD and dementia (PDD), and 34 elderly control subjects. Thin, coronal, contiguous images were obtained by a 1.5-T MR imager. All patient groups had significantly smaller volumes of the hippocampus compared with the control group. In the PDD group, the absolute volumes were even smaller than in the AD group. In the PD group, the volumes were diminished to a lesser but significant extent. The volumes in the VaD group varied: of nine patients, two had no atrophy, three had unilateral, and four had bilateral atrophy. We postulate that hippocampal atrophy does not seem to be a specific phenomenon of dementia in AD but also occurs in VaD and PDD, and even in PD when no dementia is present. However, coexistence of AD pathology in our PD and VaD patients cannot be ruled out. Further studies with access to neuropathologic data are needed.

An increased frequency of apolipoprotein E E4 allele has been reported in patients with late onset Alzheimer's disease. Apolipoprotein E participates in the transport of cholesterol and other lipids and interferes with the growth and regeneration of both peripheral and central nervous system tissues during development and after injury. Apolipoprotein E is also implicated in synaptogenesis. Apolipoprotein E isoforms differ in binding to amyloid-beta-protein and tau protein in vitro. Here, we wanted to study the effect of apolipoprotein E genotype on the magnitude of damage in the hippocampus, where a marked synapse loss exists in Alzheimer's disease. We measured by magnetic resonance imaging the volumes of the hippocampus, amygdala, and frontal lobes in the three Alzheimer subgroups: patients with 2, 1 or 0 E4 alleles. We also investigated the profile of deficits on tests assessing memory, language, visuospatial, executive, and praxic functions of these Alzheimer subgroups. All Alzheimer patients were at early stage of the disease. We found that Alzheimer patients with E4/4 genotype (N = 5) had smaller volumes of the hippocampus and the amygdala than those with E3/4 (N = 9) and those with E3/3 or E2/3 (N = 12). The difference was significant for the right hippocampus (-54% of control) and the right amygdala (-37% of control). The volumes of the frontal lobes were similar across the Alzheimer subgroups. The patients with E4/4 also showed lowest scores on delayed memory tests and differed from E3/3, 3/2 patients in the list learning test (< 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Psychopathy is characterized by abnormal emotional processes, but only recent neuroimaging studies have investigated its cerebral correlates. The study aim was to map local differences of cortical and amygdalar morphology. Cortical pattern matching and radial distance mapping techniques were used to analyze the magnetic resonance images of 26 violent male offenders (age: 32±8) with psychopathy diagnosed using the Psychopathy Checklist-Revised (PCL-R) and no schizophrenia spectrum disorders, and in matched controls (age: 35± sp="0.12"/>11). The cortex displayed up to 20% reduction in the orbitofrontal and midline structures (corrected p

Performance in olfactory identification was studied in mild cognitive impairment (MCI), using slightly expanded standard clinical approach to study the olfactory nerve. Four hundred and eighty-six cognitively normal individuals and 72 individuals with MCI underwent spontaneous and cued odor identification and delayed odor recall. Performance in these was compared with the performance in the CERAD version of the Boston Naming Test (BNT). The individuals with MCI scores significantly worse in all tests compared with controls, but the performance in tests assessing odor were less impaired than performance in the BNT. Standard assessment of olfactory nerve function is not sufficient to study cognitive impairment in MCI.

The concept of mild cognitive impairment (MCI) has been proposed to represent a transitional stage between normal aging and dementia. We studied the predictive value of the MRI-derived volumes of medial temporal lobe (MTL) structures, white matter lesions (WML), neuropsychological tests, and Apolipoprotein E (APOE) genotype on conversion of MCI to dementia and AD. The study included 60 subjects with MCI identified from population cohorts. During the mean follow-up period of 34 months, 13 patients had progressed to dementia (9 to Alzheimer's disease (AD)). In Cox regression analysis the baseline volumes of the right hippocampus, the right entorhinal cortex and CDR sum of boxes predicted the progression of MCI to dementia during the follow-up. In a bivariate analysis, only the baseline volumes of entorhinal cortex predicted conversion of MCI to AD. The Mini-Mental State Examination (MMSE) score at baseline, WML load, or APOE genotype were not significant predictors of progression. The MTL volumetry helps in identifying among the MCI subjects a group, which is at high risk for developing AD.

We investigated the effect of apolipoprotein E (ApoE) on the whole brain in 51 individuals with mild cognitive impairment using voxel-based morphometry. Between cases heterozygous for the ApoE Ε4 (n = 15) and those who were ApoE Ε4 noncarriers (n = 28), only the right parahippocampal gyrus, with the entorhinal cortex included, reached the level of statistical significance. In cases homozygous for the Ε4 allele (n = 8) versus noncarriers, the greatest atrophy was located in the right amygdala followed by the right parahippocampal gyrus, the left amygdala and the left medial dorsal thalamic nucleus.

Objectives – To assess the correlation of diffusion-weighted (DWI) and perfusion-weighted imaging (PWI) findings with the severity of acute neurologic deficit and their ability to predict short and long-term clinical outcomes of stroke. The ability of DWI and PWI to predict the outcome was compared with the ability of clinical stroke scales to predict the outcome. Methods – Forty-eight patients with acute stroke underwent diffusion DWI and PWI on the first and eighth day after the ictus. Clinical and functional scales were carried out before each scan and 3 months after the stroke. Results – The volumes of both the DWI and the PWI lesions correlated well with the acute neurologic deficit and the final outcome. The first day PWI (r = 0.64) and the National Institutes of Health Stroke Scale (NIHSS) scores (r = 0.70) correlated well with the final outcome. However, in logistic regression analysis, only the NIHSS score at the acute stage was the only independent predictor of the long-term clinical outcome. Conclusion – While the PWI and DWI lesion volumes correlated well with the outcome of the stroke, the imaging measurements did not improve the prognostic power over plain clinical stroke scale scores.