HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Takahashi, M. Articles by Hackney, D. B. Search for Related Content PubMed PubMed Citation Articles by Takahashi, M. Articles by Hackney, D. B.

Diffusional Anisotropy in Cranial Nerves with Maturation: Quantitative Evaluation with Diffusion MR Imaging in Rats¹

¹ From the Department of Radiology, University of Pennsylvania Medical Center, Founders Basement/MRI, 3400 Spruce St, Philadelphia, PA 19104 (M.T., D.B.H.); the Research Department, Nihon Schering K.K., Osaka, Japan (M.T.); the Department of Pediatrics D-5, Developmental Medicine (J.O.), and First Department of Anatomy (M.M.), Osaka University Graduate School of Medical Science, Osaka, Japan; and the Division of Radiology, Kaizuka City Hospital, Osaka, Japan (K.H.). Received July 27, 1999; revision requested September 29; revision received January 11, 2000; accepted February 1. Address correspondence to M.T. (e-mail: takahash@oasis.rad.upenn.edu).

PURPOSE: To investigate the correlation between diffusional anisotropy and developmental changes in anatomy, which include myelination, in central and peripheral nerves in an animal model by using quantitative diffusion magnetic resonance (MR) imaging and electron microscopy.

MATERIALS AND METHODS: In vivo transverse and longitudinal apparent diffusion coefficients (ADCs) of the optic and trigeminal nerves in 2–10-week-old rats were measured with MR imaging. Then the animals were sacrificed at each time point, and transverse and longitudinal sections of optic and trigeminal nerves were studied with electron microscopy.

RESULTS: In the optic nerve, the ADC parallel to the neurofibers increased with development and increased contemporaneously with myelination, while the ADC perpendicular to the nerve did not change. This resulted in a significant increase in diffusional anisotropy. There were no significant changes in ADCs in either direction in the trigeminal nerve. Longitudinal sections of optic nerve showed a marked change in the orientation of each fiber. As development proceeded, the axons, which initially followed tortuous courses, assumed straighter and more parallel orientations. Trigeminal nerves displayed straight parallel courses at 2 weeks that did not change over the study period.

CONCLUSION: Changes in fiber anatomy in maturation from tortuous to straighter and more parallel orientation can account for changes in longitudinal ADC and in diffusional anisotropy.

Index terms: Animals • Nerves, cranial, 144.91, 151.91 • Nerves, optic, 144.91 • Nerves, MR, 144.121411, 151.121411 • Nerves, trigeminal, 151.91

This article has been cited by other articles:

				S.J.P.M. van Engelen, L.C. Krab, H.A. Moll, A. de Goede-Bolder, S.M.F. Pluijm, C.E. Catsman-Berrevoets, Y. Elgersma, and M.H. Lequin Quantitative Differentiation Between Healthy and Disordered Brain Matter in Patients with Neurofibromatosis Type I Using Diffusion Tensor Imaging AJNR Am. J. Neuroradiol., April 1, 2008; 29(4): 816 - 822. [Abstract] [Full Text] [PDF]

				T. J. Eluvathingal, K. M. Hasan, L. Kramer, J. M. Fletcher, and L. Ewing-Cobbs Quantitative Diffusion Tensor Tractography of Association and Projection Fibers in Normally Developing Children and Adolescents Cereb Cortex, December 1, 2007; 17(12): 2760 - 2768. [Abstract] [Full Text] [PDF]

				A. Drobyshevsky, S.-K. Song, G. Gamkrelidze, A. M. Wyrwicz, M. Derrick, F. Meng, L. Li, X. Ji, B. Trommer, D. J. Beardsley, et al. Developmental Changes in Diffusion Anisotropy Coincide with Immature Oligodendrocyte Progression and Maturation of Compound Action Potential J. Neurosci., June 22, 2005; 25(25): 5988 - 5997. [Abstract] [Full Text] [PDF]

				E. D. Schwartz, E. T. Cooper, C.-L. Chin, S. Wehrli, A. Tessler, and D. B. Hackney Ex vivo Evaluation of ADC Values within Spinal Cord White Matter Tracts AJNR Am. J. Neuroradiol., February 1, 2005; 26(2): 390 - 397. [Abstract] [Full Text] [PDF]

				V. J. Schmithorst, M. Wilke, B. J. Dardzinski, and S. K. Holland Correlation of White Matter Diffusivity and Anisotropy with Age during Childhood and Adolescence: A Cross-sectional Diffusion-Tensor MR Imaging Study Radiology, January 1, 2002; 222(1): 212 - 218. [Abstract] [Full Text] [PDF]