For Publishers
DiscoveryMetadataPeer reviewHostingPublishing
For Researchers
JoinPublishReviewCollect
Register
Blog
About
Search
Advanced search
My ScienceOpen
Search
For Publishers
For Researchers
Blog
About
86
views
34
references
 Top references
cited by
17
    
0 reviews
 Review
0
comments
 Comment
0
recommends
+1 Recommend
0 collections
    0
    shares
      49
      similar
       All similar
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Correlation between brain volume change and T2 relaxation time induced by dehydration and rehydration: Implications for monitoring atrophy in clinical studies

      research-article

      Read this article at

      ScienceOpenPublisherPMC
      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

          Brain volume change measured from magnetic resonance imaging (MRI) provides a widely used and useful in vivo measure of irreversible tissue loss. These measurements, however, can be influenced by reversible factors such as shifts in brain water content. Given the strong effect of water on T2 relaxation, we investigated whether an estimate of T2 relaxation time would correlate with brain volume changes induced by physiologically manipulating hydration status. We used a clinically feasible estimate of T2 (“pseudo-T2”) computed from a dual turbo spin-echo MRI sequence and correlated pseudo-T2 changes to percent brain volume changes in 12 healthy subjects after dehydration overnight (16-hour thirsting) and rehydration (drinking 1.5 L of water).

          We found that the brain volume significantly increased between the dehydrated and rehydrated states (mean brain volume change = 0.36%, p = 0.0001) but did not change significantly during the dehydration interval (mean brain volume change = 0.04%, p = 0.57). The changes in brain volume and pseudo-T2 significantly correlated with each other, with marginal and conditional correlations ( R 2) of 0.44 and 0.65, respectively.

          Our results show that pseudo-T2 may be used in conjunction with the measures of brain volume to distinguish reversible water fluctuations and irreversible brain tissue loss (atrophy) and to investigate disease mechanisms related to neuro-inflammation, e.g., in multiple sclerosis, where edema-related water fluctuations may occur with disease activity and anti-inflammatory treatment.

          Highlights

          • •

            Brain volumes significantly changed with hydration status in normal volunteers.

          • •

            The volume change correlates with the change in T2 relaxation time.

          • •

            The method can be applied to estimate brain water fluctuations in clinical studies.

          • •

            The method allows investigations on pseudoatrophy effect in MS clinical trials.

          Related collections

          Most cited references34

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

          Automatic 3D intersubject registration of MR volumetric data in standardized Talairach space.

          D L Collins, P Neelin, T Peters … (1994)
          In both diagnostic and research applications, the interpretation of MR images of the human brain is facilitated when different data sets can be compared by visual inspection of equivalent anatomical planes. Quantitative analysis with predefined atlas templates often requires the initial alignment of atlas and image planes. Unfortunately, the axial planes acquired during separate scanning sessions are often different in their relative position and orientation, and these slices are not coplanar with those in the atlas. We have developed a completely automatic method to register a given volumetric data set with Talairach stereotaxic coordinate system. The registration method is based on multi-scale, three-dimensional (3D) cross-correlation with an average (n > 300) MR brain image volume aligned with the Talariach stereotaxic space. Once the data set is re-sampled by the transformation recovered by the algorithm, atlas slices can be directly superimposed on the corresponding slices of the re-sampled volume. the use of such a standardized space also allows the direct comparison, voxel to voxel, of two or more data sets brought into stereotaxic space. With use of a two-tailed Student t test for paired samples, there was no significant difference in the transformation parameters recovered by the automatic algorithm when compared with two manual landmark-based methods (p > 0.1 for all parameters except y-scale, where p > 0.05). Using root-mean-square difference between normalized voxel intensities as an unbiased measure of registration, we show that when estimated and averaged over 60 volumetric MR images in standard space, this measure was 30% lower for the automatic technique than the manual method, indicating better registrations. Likewise, the automatic method showed a 57% reduction in standard deviation, implying a more stable technique. The algorithm is able to recover the transformation even when data are missing from the top or bottom of the volume. We present a fully automatic registration method to map volumetric data into stereotaxic space that yields results comparable with those of manually based techniques. The method requires no manual identification of points or contours and therefore does not suffer the drawbacks involved in user intervention such as reproducibility and interobserver variability.
          Article 0 comments Cited 334 times – based on 0 reviews     Review now
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Gray matter atrophy in multiple sclerosis: a longitudinal study.

            Chi-Ming Lee, Richard Rudick, Elizabeth Fisher … (2008)
            To determine gray matter (GM) atrophy rates in multiple sclerosis (MS) patients at all stages of disease, and to identify predictors and clinical correlates of GM atrophy. MS patients and healthy control subjects were observed over 4 years with standardized magnetic resonance imaging (MRI) and neurological examinations. Whole-brain, GM, and white matter atrophy rates were calculated. Subjects were categorized by disease status and disability progression to determine the clinical significance of atrophy. MRI predictors of atrophy were determined through multiple regression. Subjects included 17 healthy control subjects, 7 patients with clinically isolated syndromes, 36 patients with relapsing-remitting MS (RRMS), and 27 patients with secondary progressive MS (SPMS). Expressed as fold increase from control subjects, GM atrophy rate increased with disease stage, from 3.4-fold normal in clinically isolated syndromes patients converting to RRMS to 14-fold normal in SPMS. In contrast, white matter atrophy rates were constant across all MS disease stages at approximately 3-fold normal. GM atrophy correlated with disability. MRI measures of focal and diffuse tissue damage accounted for 62% of the variance in GM atrophy in RRMS, but there were no significant predictors of GM atrophy in SPMS. Gray matter tissue damage dominates the pathological process as MS progresses, and underlies neurological disabillity. Imaging correlates of gray matter atrophy indicate that mechanisms differ in RRMS and SPMS. These findings demonstrate the clinical relevance of gray matter atrophy in MS, and underscore the need to understand its causes.
            Article 0 comments Cited 184 times – based on 0 reviews     Review now
              Bookmark
              • Record: found
              • Abstract: not found
              • Article: not found

              R: A language and enviornment for statistical computing

              (2010)
              Article 0 comments Cited 179 times – based on 0 reviews     Review now
                Bookmark
                All references

                Author and article information

                Contributors
                Kunio Nakamura
                Journal
                Journal ID (nlm-ta): Neuroimage Clin
                Journal ID (iso-abbrev): Neuroimage Clin
                Title: NeuroImage : Clinical
                Publisher: Elsevier
                ISSN (Electronic): 2213-1582
                Publication date PMC-release: 23 August 2014
                Publication date (Electronic): 23 August 2014
                Publication date Collection: 2014
                Volume: 6
                Pages: 166-170
                Affiliations
                [a ]McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, Quebec H3A 2B4, Canada
                Author notes
                [* ]Corresponding author. knakamura@ 123456mrs.mni.mcgill.ca
                Article
                Publisher ID: S2213-1582(14)00123-5
                DOI: 10.1016/j.nicl.2014.08.014
                PMC ID: 4215533
                PubMed ID: 25379428
                SO-VID: ec1eed5b-0e6b-4823-802d-7d170513d2a1
                Copyright © © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
                License:

                This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

                History
                Date received : 4 June 2014
                Date revision received : 25 July 2014
                Date accepted : 19 August 2014
                Categories
                Subject: Article

                Keywords: brain volumetry,brain water content,t2 relaxation time
                Data availability:
                Keywords: brain volumetry, brain water content, t2 relaxation time

                Comments

                Comment on this article

                scite_

                Similar content49

                See all similar

                Cited by35

                See all cited by

                Most referenced authors472

                See all reference authors