Postmortem MRI of human brain hemispheres: T2 relaxation times during formaldehyde fixation
Open Access
- 2 February 2009
- journal article
- research article
- Published by Wiley in Magnetic Resonance in Medicine
- Vol. 61 (4), 810-818
- https://doi.org/10.1002/mrm.21909
Abstract
Unlike in vivo imaging, postmortem MRI allows for invasive examination of the tissue specimen immediately after the MR scan. However, natural tissue decomposition and chemical fixation cause the postmortem tissue's MRI properties to be different from those found in vivo. Moreover, these properties change as postmortem fixation time elapses. The goal of this study was to characterize the T2 relaxation changes that occur over time in cadaveric human brain hemispheres during fixation. Five hemispheres immersed in formaldehyde solution were scanned on a weekly basis for 3 months postmortem, and once again at 6 months postmortem. The T2 relaxation times were measured throughout the hemispheres. Over time, T2 values near the edges of the hemispheres decreased rapidly after death, while T2 values of deep tissue decreased more slowly. This difference is likely due to the relatively large distance from the hemisphere surface, and other barriers limiting diffusion of formaldehyde molecules to deep tissues. In addition, T2 values in deep tissue did not continuously decay to a plateau, but instead reached a minimum and then increased to a plateau. This final increase may be due to the effects of prolonged tissue decomposition, a hypothesis that is supported by numerical simulations of the fixation process. Magn Reson Med, 2009.Keywords
This publication has 36 references indexed in Scilit:
- Fast multislice mapping of the myelin water fraction using multicompartment analysis of T decay at 3T: A preliminary postmortem studyMagnetic Resonance in Medicine, 2007
- Correlation of proton transverse relaxation rates (R2) with iron concentrations in postmortem brain tissue from alzheimer's disease patientsMagnetic Resonance in Medicine, 2006
- Cadaver decomposition in terrestrial ecosystemsThe Science of Nature, 2006
- MRI with Diffusion Tensor Imaging Post-Mortem at 3.0 T in a Patient with Frontotemporal DementiaDementia and Geriatric Cognitive Disorders, 2004
- Postmortem MR imaging of formalin-fixed human brainNeuroImage, 2004
- Identification of Formaldehyde-induced Modifications in ProteinsPublished by Elsevier BV ,2004
- Postmortem MRI and Histopathology of White Matter Changes in Alzheimer BrainsDementia and Geriatric Cognitive Disorders, 2002
- Brain MR: pathologic correlation with gross and histopathology. 2. Hyperintense white-matter foci in the elderlyAmerican Journal of Roentgenology, 1988
- Brain MR: pathologic correlation with gross and histopathology. 1. Lacunar infarction and Virchow-Robin spacesAmerican Journal of Roentgenology, 1988
- Incidental subcortical lesions identified on magnetic resonance imaging in the elderly. II. Postmortem pathological correlations.Stroke, 1986