25
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Brain perfusion in dementia with Lewy bodies and Alzheimer’s disease: an arterial spin labeling MRI study on prodromal and mild dementia stages

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background

          We aimed to describe specific changes in brain perfusion in patients with dementia with Lewy bodies (DLB) at both the prodromal (also called mild cognitive impairment) and mild dementia stages, relative to patients with Alzheimer’s disease (AD) and controls.

          Methods

          Altogether, 96 participants in five groups (prodromal DLB, prodromal AD, DLB with mild dementia, AD with mild dementia, and healthy elderly controls) took part in an arterial spin labeling MRI study. Three analyses were performed: a global perfusion value comparison, a voxel-wise analysis of both absolute and relative perfusion, and a linear discriminant analysis. These were used to assess the global decrease in perfusion, regional changes, and the sensitivity and specificity of these changes.

          Results

          Patterns of perfusion in DLB differed from AD and controls in both the prodromal stage and dementia, DLB having more deficits in frontal, insular, and temporal cortices whereas AD showed reduced perfusion in parietal and parietotemporal cortices. Decreases but also increases of perfusion in DLB relative to controls were observed in both absolute and relative measurements. All these regional changes of perfusion classified DLB patients with respect to either healthy controls or AD with sensitivity from 87 to 100 % and specificity from 90 to 96 % depending on the stage of the disease.

          Conclusions

          Our results are consistent with previous studies. We extend the scope of those studies by integrating prodromal DLB patients and by describing both hypo- and hyperperfusion in DLB. While decreases in perfusion may relate to functional impairments, increases might suggest a functional compensation of some brain areas.

          Electronic supplementary material

          The online version of this article (doi:10.1186/s13195-016-0196-8) contains supplementary material, which is available to authorized users.

          Related collections

          Most cited references31

          • Record: found
          • Abstract: found
          • Article: not found

          Aging gracefully: compensatory brain activity in high-performing older adults.

          Whereas some older adults show significant cognitive deficits, others perform as well as young adults. We investigated the neural basis of these different aging patterns using positron emission tomography (PET). In PET and functional MRI (fMRI) studies, prefrontal cortex (PFC) activity tends to be less asymmetric in older than in younger adults (Hemispheric Asymmetry Reduction in Old Adults or HAROLD). This change may help counteract age-related neurocognitive decline (compensation hypothesis) or it may reflect an age-related difficulty in recruiting specialized neural mechanisms (dedifferentiation hypothesis). To compare these two hypotheses, we measured PFC activity in younger adults, low-performing older adults, and high-performing older adults during recall and source memory of recently studied words. Compared to recall, source memory was associated with right PFC activations in younger adults. Low-performing older adults recruited similar right PFC regions as young adults, but high-performing older adults engaged PFC regions bilaterally. Thus, consistent with the compensation hypothesis and inconsistent with the dedifferentiation hypothesis, a hemispheric asymmetry reduction was found in high-performing but not in low-performing older adults. The results suggest that low-performing older adults recruited a similar network as young adults but used it inefficiently, whereas high-performing older adults counteracted age-related neural decline through a plastic reorganization of neurocognitive networks.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            A new rating scale for age-related white matter changes applicable to MRI and CT.

            MRI is more sensitive than CT for detection of age-related white matter changes (ARWMC). Most rating scales estimate the degree and distribution of ARWMC either on CT or on MRI, and they differ in many aspects. This makes it difficult to compare CT and MRI studies. To be able to study the evolution and possible effect of drug treatment on ARWMC in large patient samples, it is necessary to have a rating scale constructed for both MRI and CT. We have developed and evaluated a new scale and studied ARWMC in a large number of patients examined with both MRI and CT. Seventy-seven patients with ARWMC on either CT or MRI were recruited and a complementary examination (MRI or CT) performed. The patients came from 4 centers in Europe, and the scans were rated by 4 raters on 1 occasion with the new ARWMC rating scale. The interrater reliability was evaluated by using kappa statistics. The degree and distribution of ARWMC in CT and MRI scans were compared in different brain areas. Interrater reliability was good for MRI (kappa=0.67) and moderate for CT (kappa=0.48). MRI was superior in detection of small ARWMC, whereas larger lesions were detected equally well with both CT and MRI. In the parieto-occipital and infratentorial areas, MRI detected significantly more ARWMC than did CT. In the frontal area and basal ganglia, no differences between modalities were found. When a fluid-attenuated inversion recovery sequence was used, MRI detected significantly more lesions than CT in frontal and parieto-occipital areas. No differences were found in basal ganglia and infratentorial areas. We present a new ARWMC scale applicable to both CT and MRI that has almost equal sensitivity, except for certain regions. The interrater reliability was slightly better for MRI, as was the detectability of small lesions.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              The Clinician Assessment of Fluctuation and the One Day Fluctuation Assessment Scale. Two methods to assess fluctuating confusion in dementia.

              The identification of fluctuating confusion is central to improving the differential diagnosis of the common dementias. To determine the value of two rating scales to measure fluctuating confusion. The agreement between the clinician-rated scale and the scale completed by a non-clinician was determined. Correlations between the two scales were calculated; variability in attention was calculated on a computerised cognitive assessment and variability in delta rhythm on an electroencephalogram (EEG). The Clinician Assessment of Fluctuation and the computerised cognitive assessment were completed for 155 patients (61 Alzheimer's disease, 37 dementia with Lewy bodies, 22 vascular dementia, 35 elderly controls). A subgroup (n = 40) received a further evaluation using the One Day Fluctuation Assessment Scale and an EEG. The two scales correlated significantly with each other, and with the neuropsychological and electrophysiological measures of fluctuation. Both scales are useful instruments for the clinical assessment of fluctuation in dementia.
                Bookmark

                Author and article information

                Contributors
                daniel.roquet@unistra.fr
                sourty@unistra.fr
                anne.botzung@chru-strasbourg.fr
                jparmspach@unistra.fr
                f.blanc@unistra.fr
                Journal
                Alzheimers Res Ther
                Alzheimers Res Ther
                Alzheimer's Research & Therapy
                BioMed Central (London )
                1758-9193
                12 July 2016
                12 July 2016
                2016
                : 8
                : 29
                Affiliations
                [ ]ICube laboratory, University of Strasbourg, CNRS, FMTS(Fédération de Médecine Translationnelle de Strasbourg), ICube – IPB, Faculté de Médecine, 4 rue Kirschleger, Strasbourg, 67085 France
                [ ]University Hospital of Strasbourg, CMRR (Memory Resources and Research Centre), Strasbourg, France
                Author information
                http://orcid.org/0000-0002-0838-354X
                Article
                196
                10.1186/s13195-016-0196-8
                4940880
                27401267
                9b96e3a1-ad55-4c21-a3a5-201f8ffe79da
                © The Author(s) 2016

                Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License ( http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver ( http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

                History
                : 14 March 2016
                : 6 June 2016
                Funding
                Funded by: AG2R La Mondiale
                Categories
                Research
                Custom metadata
                © The Author(s) 2016

                Neurology
                cerebral blood flow,prodromal phase,mri,early diagnosis,insula
                Neurology
                cerebral blood flow, prodromal phase, mri, early diagnosis, insula

                Comments

                Comment on this article