Blog
About

  • Record: found
  • Abstract: found
  • Article: found
Is Open Access

Diffusion Tensor Imaging of Heterotopia: Changes of Fractional Anisotropy during Radial Migration of Neurons

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

      Purpose

      Diffusion tensor imaging provides better understanding of pathophysiology of congenital anomalies, involving central nervous system. This study was aimed to specify the pathogenetic mechanism of heterotopia, proved by diffusion tensor imaging, and establish new findings of heterotopia on fractional anisotropy maps.

      Materials and Methods

      Diffusion-weighted imaging data from 11 patients (M : F = 7 : 4, aged from 1 to 22 years, mean = 12.3 years) who visited the epilepsy clinic and received a routine seizure protocol MRI exam were retrospectively analyzed. Fractional anisotropy (FA) maps were generated from diffusion tensor imaging of 11 patients with heterotopia. Regions of interests (ROI) were placed in cerebral cortex, heterotopic gray matter and deep gray matter, including putamen. ANOVA analysis was performed for comparison of different gray matter tissues.

      Results

      Heterotopic gray matter showed signal intensities similar to normal gray matter on T1 and T2 weighted MRI. The measured FA of heterotopic gray matter was higher than that of cortical gray matter (0.236 ± 0.011 vs. 0.169 ± 0.015, p < 0.01, one way ANOVA), and slightly lower than that of deep gray matter (0.236 ± 0.011 vs. 0.259 ± 0.016, p < 0.01).

      Conclusion

      Increased FA of heterotopic gray matter suggests arrested neuron during radial migration and provides better understanding of neurodevelopment.

      Related collections

      Most cited references 15

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

      Diffusion-tensor MR imaging and tractography: exploring brain microstructure and connectivity.

      Diffusion magnetic resonance (MR) imaging is evolving into a potent tool in the examination of the central nervous system. Although it is often used for the detection of acute ischemia, evaluation of directionality in a diffusion measurement can be useful in white matter, which demonstrates strong diffusion anisotropy. Techniques such as diffusion-tensor imaging offer a glimpse into brain microstructure at a scale that is not easily accessible with other modalities, in some cases improving the detection and characterization of white matter abnormalities. Diffusion MR tractography offers an overall view of brain anatomy, including the degree of connectivity between different regions of the brain. However, optimal utilization of the wide range of data provided with directional diffusion MR measurements requires careful attention to acquisition and postprocessing. This article will review the principles of diffusion contrast and anisotropy, as well as clinical applications in psychiatric, developmental, neurodegenerative, neoplastic, demyelinating, and other types of disease.
        Bookmark
        • Record: found
        • Abstract: found
        • Article: not found

        Neuronal migration disorders: from genetic diseases to developmental mechanisms.

        Neurons that constitute the cerebral cortex must migrate hundreds of cell-body distances from their place of birth, and through several anatomical boundaries, to reach their final position within the correct cortical layer. Human neurological conditions associated with abnormal neuronal migration, together with spontaneous and engineered mouse mutants, define at least four distinct steps in cortical neuronal migration. Many of the genes that control neuronal migration have strong genetic or biochemical links to the cytoskeleton, suggesting that the field of neuronal migration might be closing in on the underlying cytoskeletal events.
          Bookmark
          • Record: found
          • Abstract: found
          • Article: not found

          Exploring white matter tracts in band heterotopia using diffusion tractography.

          Band heterotopia is a malformation of cortical development characterized by bands of gray matter in the white matter parallel to the surface of the neocortex. Histopathological studies have suggested that small white matter tracts pass through the heterotopia, and functional magnetic resonance imaging studies have shown activation in the malformation. We used diffusion tractography to explore the anatomical connectivity of band heterotopia and, in particular, whether in vivo white matter tracts traverse the heterotopic gray matter. Five patients with band heterotopia and five control subjects were scanned with whole brain diffusion tensor imaging. Anisotropy maps were calculated. Using fast marching tractography, we produced maps of connectivity and tract traces from two seed points, in the splenium of the corpus callosum and the right parietal lobe. Eigenvectors were found to pass through the band heterotopia in an aligned fashion. Patterns for maps of connectivity were similar in patients and control subjects. Areas of high connectivity were found in the band heterotopia and in cortical areas on the far side of the malformation from the seed point. The tracts hence appeared to traverse or end within the band heterotopia. The results are in agreement with previous histopathological studies and indicate the structural basis of the functional connectivity and absence of focal deficits in these patients.
            Bookmark

            Author and article information

            Affiliations
            Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, Seoul, Korea.
            Author notes
            Corresponding author: Dr. Seung-Koo Lee, Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, 250 Seongsan-ro, Seodaemun-gu, Seoul 120-752, Korea. Tel: 82-2-2228-2373, Fax: 82-2-393-3035, slee@ 123456yuhs.ac
            Journal
            Yonsei Med J
            YMJ
            Yonsei Medical Journal
            Yonsei University College of Medicine
            0513-5796
            1976-2437
            01 July 2010
            24 May 2010
            : 51
            : 4
            : 590-593
            2880275
            20499428
            10.3349/ymj.2010.51.4.590
            © Copyright: Yonsei University College of Medicine 2010

            This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted noncommercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

            Categories
            Original Article
            Medical Imaging

            Medicine

            heterotopia, congenital malformation, magnetic resonance imaging

            Comments

            Comment on this article