Quantitative Evaluation of the Corticospinal Tract Segmented by Using Co-registered Functional MRI and Diffusion Tensor Tractography

정상인에서 기능적 뇌 자기공명영상과 확산텐서영상 합성기법을 이용한 피질척수로의 위치에 따른 정량적 분석

  • Jang, Sung-Ho (Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University) ;
  • Hong, Ji-Heon (Department of Rehabilitation Science, Taegu University) ;
  • Byun, Woo-Mok (Department of Diagnostic Radiology, College of Medicine, Yeungnam University) ;
  • Hwang, Chang-Ho (Department of Physical Medicine and Rehabilitation Medicine, Ulsan University Hospital College of Medicine, Ulsan University) ;
  • Yang, Dong-Seok (Department of Physical Medicine and Rehabilitation Medicine, Ulsan University Hospital College of Medicine, Ulsan University)
  • 장성호 (영남대학교 의과대학 재활의학교실) ;
  • 홍지헌 (대구대학교 재활과학대학원) ;
  • 변우목 (영남대학교 의과대학 영상의학교실) ;
  • 황창호 (울산대학교 의과대학 울산대병원 재활의학교실) ;
  • 양동석 (울산대학교 의과대학 울산대병원 재활의학교실)
  • Published : 2009.06.30

Abstract

Purpose : The purpose of this study was to investigate the quantitative evaluation of the corticospinal tract (CST) at the multiple levels by using functional MRI (fMRI) co-registered to diffusion tensor tractography (DTT). Materials and Methods : Ten normal subjects without any history of neurological disorder participated in this study. fMRI was performed at 1.5 T MR scanner using hand grasp-release movement paradigm. DTT was performed by using DtiStudio on the basis of fiber assignment continuous tracking algorithm (FACT). The seed region of interest (ROI) was drawn in the area of maximum fMRI activation during the motor task of hand grasp-release movement on a 2-D fractional anisotropy (FA) color map, and the target ROI was drawn in the cortiocospinal portion of anterior lower pons. We have drawn five ROIs for the measurement of FA and apparent diffusion coefficient (ADC) along the corona radiata (CR) down to the medulla. Results : The contralateral primary sensorimotor cortex (SM1) was mainly found to be activated in all subjects. DTT showed that tracts originated from SM1 and ran to the medulla along the known pathway of the CST. In all subjects, FA values of the CST were higher at the level of the midbrain and posterior limb of internal capsule (PLIC) than the level of others. Conclusion : Our study showed that co-registered fMRI and DTT has elucidated the state of CST on 3-D and analyzed the quantitative values of FA and ADC at the multiple levels. We conclude that co-registered fMRI and DTT may be applied as a useful tool for clarifying and investigating the state of CST in the patients with brain injury.

목적 : 기능적 뇌 자기공명영상 (fMRI)과 확산텐서영상(DTI) 합성기법을 이용하여 피질척수로의 여러 부위에서 정량적 특성을 연구하고자 하였다. 대상 및 방법 : 신경학적 이상이 없는 정상인 10명 (남: 8, 여: 2, 평균연령: 30세, 연령분포 : 22 -38세)을 대상으로 하였다. fMRI는 1.5T를 이용하였으며, 손의 쥐기 펴기를 수행하였다. fMRI와 확산텐서섬유로(DTT)의 합성이 가능한 DtiStudio 프로그램을 이용하여 피질척수로를 3차원 영상화하였다. 이때, 시작 관심영역은 2차원 분할 비등방성(fractional anisotropy, FA) 색지도(color map)에서 fMRI의 운동 수행 시 활성부위가 가장 많은 곳으로, 목표 관심영역은 하부 전방 뇌교의 피질척수 부위로 설정하였다. 정량적 분석을 위하여 관심영역을 부채살부터 연수까지 좌우 각각 5곳에 설정하여 분할 비등방성과 현성 확산계수(ADC)를 측정하였다. 결과 : 모든 대상자는 fMRI에서 일차 감각운동 영역이 주로 활성화되었다. 확산텐서 영상에서 피질척수로의 경로는 일차 감각운동 영역부터 연수까지 주행하였다. 피질척수로의 FA 값은 모든 대상자에서 중뇌와 내측 섬유띠의 후지가 타 부위보다 높았다. 결론 : fMRI와 DTT의 합성기법은 피질척수로 상태의 3차원 영상화 및 각 부위에서 FA와 ADC값을 이용한 정량적 분석이 가능하였다. 앞으로, fMRI와 DTT 합성기법은 뇌손상 환자에서 피질척수로의 명확한 상태를 연구하는 데 유용하게 이용될 것으로 사료된다.

Keywords

References

  1. Davidoff RA. The pyramidal tract. Neurology 1990;40:332-339. https://doi.org/10.1212/WNL.40.2.332
  2. Martin JH. The corticospinal system: from development to motor control. Neuroscientist 2005;11:161-173. https://doi.org/10.1177/1073858404270843
  3. Wiesendanger M. Pyramidal tract function and the clinical "pyramidal syndrome". Hum Neurobiol 1984;2:227-234.
  4. Ahn YH, Ahn SH, Kim H, Hong JH, Jang SH. Can stroke patients walk after complete lateral corticospinal tract injury of the affected hemisphere- Neuroreport 2006;17:987-990. https://doi.org/10.1097/01.wnr.0000220128.01597.e0
  5. Chollet F, DiPiero V, Wise RJ, Brooks DJ, Dolan RJ, Frackowiak RS. The functional anatomy of motor recovery after stroke in humans: a study with positron emission tomography. Ann Neurol 1991;29:63-71. https://doi.org/10.1002/ana.410290112
  6. Macdonell RA, Jackson GD, Curatolo JM, et al. Motor cortex localization using functional MRI and transcranial magnetic stimulation. Neurology 1999;53:1462-1467. https://doi.org/10.1212/WNL.53.7.1462
  7. Cramer SC. Changes in motor system function and recovery after stroke. Restor Neurol Neurosci 2004;22:231-238.
  8. Basser PJ, Pierpaoli C. Microstructural and physiological features of tissues elucidated by quantitative-diffusion-tensor MRI. J Magn Reson B 1996;111:209-219. https://doi.org/10.1006/jmrb.1996.0086
  9. 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;45:265-269. https://doi.org/10.1002/1531-8249(199902)45:2<265::AID-ANA21>3.0.CO;2-3
  10. Ronen I, Ugurbil K, Kim DS. How does DWI correlate with white matter structures- Magn Reson Med 2005;54:317-323. https://doi.org/10.1002/mrm.20542
  11. Conturo TE, Lori NF, Cull TS, et al. Tracking neuronal fiber pathways in the living human brain. Proc Natl Acad Sci U S A 1999;96:10422-10427. https://doi.org/10.1073/pnas.96.18.10422
  12. Chenevert TL, Brunberg JA, Pipe JG. Anisotropic diffusion in human white matter: demonstration with MR techniques in vivo. Radiology 1990;177:401-405. https://doi.org/10.1148/radiology.177.2.2217776
  13. Pierpaoli C, Jezzard P, Basser PJ, Barnett A, Di Chiro G. Diffusion tensor MR imaging of the human brain. Radiology 1996;201:637-648. https://doi.org/10.1148/radiology.201.3.8939209
  14. Ciccarelli O, Parker GJ, Toosy AT, et al. From diffusion tractography to quantitative white matter tract measures: a reproducibility study. Neuroimage 2003;18:348-359. https://doi.org/10.1016/S1053-8119(02)00042-3
  15. Stieltjes B, Kaufmann WE, van Zijl PC, et al. Diffusion tensor imaging and axonal tracking in the human brainstem. Neuroimage 2001;14:723-735. https://doi.org/10.1006/nimg.2001.0861
  16. Kunimatsu A, Aoki S, Masutani Y, et al. The optimal trackability threshold of fractional anisotropy for diffusion tensor tractography of the corticospinal tract. Magn Reson Med Sci 2004;3:11-17. https://doi.org/10.2463/mrms.3.11
  17. Oldfield RC. The assessment and analysis of handedness: the Edinburgh inventory. Neuropsychologia 1971;9:97-113. https://doi.org/10.1016/0028-3932(71)90067-4
  18. Jiang H, van Zijl PC, Kim J, Pearlson GD, Mori S. DtiStudio: resource program for diffusion tensor computation and fiber bundle tracking. Comput Methods Programs Biomed 2006;81:106-116. https://doi.org/10.1016/j.cmpb.2005.08.004
  19. Parker GJ, Wheeler-Kingshott CA, Barker GJ. Estimating distributed anatomical connectivity using fast marching methods and diffusion tensor imaging. IEEE Trans Med Imaging 2002;21:505-512. https://doi.org/10.1109/TMI.2002.1009386
  20. Virta A, Barnett A, Pierpaoli C. Visualizing and characterizing white matter fiber structure and architecture in the human pyramidal tract using diffusion tensor MRI. Magn Reson Imaging 1999;17:1121-1133. https://doi.org/10.1016/S0730-725X(99)00048-X
  21. Toosy AT, Werring DJ, Orrell RW, et al. Diffusion tensor imaging detects corticospinal tract involvement at multiple levels in amyotrophic lateral sclerosis. J Neurol Neurosurg Psychiatry 2003;74:1250-1257. https://doi.org/10.1136/jnnp.74.9.1250
  22. Ahn YH, Kim SH, Han BS, et al. Focal lesions of the corticospinal tract demonstrated by diffusion tensor imaging in patients with diffuse axonal injury. NeuroRehabilitation 2006;21:239-243.
  23. Wong JC, Concha L, Beaulieu C, Johnston W, Allen PS, Kalra S. Spatial profiling of the corticospinal tract in amyotrophic lateral sclerosis using diffusion tensor imaging. J Neuroimaging 2007;17:234-240. https://doi.org/10.1111/j.1552-6569.2007.00100.x
  24. Guye M, Parker GJ, Symms M, et al. Combined functional MRI and tractography to demonstrate the connectivity of the human primary motor cortex in vivo. Neuroimage 2003;19:1349-1360. https://doi.org/10.1016/S1053-8119(03)00165-4
  25. Toosy AT, Ciccarelli O, Parker GJ, Wheeler-Kingshott CA, Miller DH, Thompson AJ. Characterizing function-structure relationships in the human visual system with functional MRI and diffusion tensor imaging. Neuroimage 2004;21:1452-1463. https://doi.org/10.1016/j.neuroimage.2003.11.022
  26. Upadhyay J, Ducros M, Knaus TA, et al. Function and Connectivity in Human Primary Auditory Cortex: A Combined fMRI and DTI Study at 3 Tesla. Cereb Cortex 2007;17:2420-2432. https://doi.org/10.1093/cercor/bhl150
  27. Takahashi E, Ohki K, Kim DS. Diffusion tensor studies dissociated two fronto-temporal pathways in the human memory system. Neuroimage 2007;34:827-838. https://doi.org/10.1016/j.neuroimage.2006.10.009
  28. Lazar M, Weinstein DM, Tsuruda JS, et al. White matter tractography using diffusion tensor deflection. Hum Brain Mapp 2003;18:306-321. https://doi.org/10.1002/hbm.10102
  29. Hendler T, Pianka P, Sigal M, et al. Delineating gray and white matter involvement in brain lesions: three-dimensional alignment of functional magnetic resonance and diffusion-tensor imaging. J Neurosurg 2003;99:1018-1027. https://doi.org/10.3171/jns.2003.99.6.1018
  30. Cherubini A, Luccichenti G, Peran P, et al. Multimodal fMRI tractography in normal subjects and in clinically recovered traumatic brain injury patients. Neuroimage 2007;34:1331-1341. https://doi.org/10.1016/j.neuroimage.2006.11.024
  31. Ino T, Nakai R, Azuma T, Yamamoto T, Tsutsumi S, Fukuyama H. Somatotopy of corticospinal tract in the internal capsule shown by functional MRI and diffusion tensor images. Neuroreport 2007;18:665-668. https://doi.org/10.1097/WNR.0b013e3280d943e1