Full Text:
영남의대학술지 Vol.24_No.2 Suppl. P.S424-429, Dec. 2007
Original Article
Transcallosal Fibers from the Corticospinal Tract in Adults with Brain Injury
Sung Ho Jang, Sang Ho Ahn, Yun Woo Cho
Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Daegu, Korea
책임저자：장성호, 대구광역시 남구 대명5동 317-1번지, 영남대학교 의과대학 재활의학교실
Tel: (053) 620-3269(4047), Fax: (053) 625-3508
E-mail: strokerehab@hanmail.net
December 30, 2007
Abstract
Background：Diffusion tensor image tractography (DTT) can visualize white matter tracts and provide us with a powerful vehicle for investigating the neuralpathway at the subcortical level. Using DTT, we attempted to demonstrate abnormal transcallosal fibers from the corticospinal tract in patients with brain injury. Materials and Methods：Four adults with brain injury (2 patients: stroke, 1 patient: brain tumor with hemorrhage, 1 patient: diffuse axonal injury) and 14 normal control subjects were enrolled in this study. DTT was performed using 1.5-T with a Synergy-L Sensitivity Encoding head coil. Three-dimensional reconstructions of the fiber tracts were obtained with FA<3.0, and an angle change >45o as termination criteria. Results：Transcallosal fibers were observed in two of 14 normal controls, and ascended to the cortex leaving the corpus callosum. All four patients showed transcallosal fibers which stemmed from the corticospinal tract of the unaffected hemisphere, and descended to or around the lesion at the subcortical area. Conclusion：It seems that transcallosal fibers which arise from the corticospinal tract of the unaffected hemisphere may act as pathological fibers for motor deficit compensation.
Key Words: Diffusion tensor image, Brain injury, Interhemispheric inhibition, Corpus callosum
References
	1. Basser PJ, Pierpaoli C. Microstructural and physiological features of tissues elucidated by quantitative-diffusion-tensor MRI. J Magn Reson B 1996 Jun;111(3):209-19.
	2. Mori S, Crain BJ, Chacko VP, van Zijl PC. Three-dimensional tracking of axonal projections in the brain by magnetic resonance imaging. Ann Neurol 1999 Feb;45(2):265-9.
	3. Jang SH, Kim YH, Kwon YH, You S, Han BS, Byun WM. Restoration of corticospinal tract compressed by hematoma: a diffusion tensor tractography study. Arch Neurol (in press).
	4. Abe O, Masutani Y, Aoki S, Yamasue H, Yamada H, Kasai K, et al. Topography of the human corpus callosum using diffusion tensor tractography. J Comput Assist Tomogr 2004 Jul-Aug;28(4):533-9.
	5. Dougherty RF, Ben-Shachar M, Bammer R, Brewer AA, Wandell BA. Functional organization of human occipital-callosal fiber tracts. Proc Natl Acad Sci USA 2005 May 17;102(20): 7350-5.
	6. Demeurisse G, Demol O, Robaye E. Motor evaluation in vascular hemiplegia. Eur Neurol 1980;19(6):382-9.
	7. Aboitiz F, Montiel J. One hundred million years of interhemispheric communication: the history of the corpus callosum. Braz J Med Biol Res 2003 Apr;36(4):409-20.
	8. Weiller C, Chollet F, Friston KJ, Wise RJ, Frackowiak RS. Functional reorganization of the brain in recovery from striatocapsular infarction in man. Ann Neurol 1992 May; 31(5):463-72.
	9. Song YM, Lee JY, Park JM, Yoon BW, Roh JK. Ipsilateral hemiparesis caused by a corona radiata infarct after a previous stroke on the opposite side. Arch Neurol 2005 May;62(5): 809-11.
	10. Turton A, Wroe S, Trepte N, Fraser C, Lemon RN. Contralateral and ipsilateral EMG responses to transcranial magnetic stimulation during recovery of arm and hand function after stroke. Electroenceph clin Neurophysiol 1996 Aug;101(4):316-28.
	11. Netz J, Lammers T, Homberg V. Reorganization of motor output in the non-affected hemisphere after stroke. Brain 1997 Sep;120(Pt 9):1579-86.
	12. Liepert J, Hamzei F, Weiller C. Motor cortex dishinibition of the unaffected hemisphere after acute stroke. Muscle Nerve 2000 Nov; 23(11):1761-3.
	13. Manganotti P, Patuzzo S, Cortese F, Palermo A, Smania N, Fiaschi A. Motor disinhibition in affected and unaffected hemisphere in the early period of recovery after stroke. Clin Neurophysiol 2002 Jun;113(6):936-43.