|
|
||||||||
Articles |
Heavily T2-weighted high-field MR images provide a unique opportunity for the evaluation of the extrapyramidal motor system. The images are affected by the presence of small amounts of naturally occurring paramagnetic substances--principally iron--that delineate the neostriatum (caudate and putamen), globus pallidus, red nucleus, substantia nigra, and dentate nucleus, primarily by a decrease in signal secondary to the T2* effect. Movement disorders are associated with either increased or decreased signal or both in these structures, depending on the pathologic process. In the initial evaluation of 113 patients with a variety of movement disorders, good correlation of imaging abnormalities can be made with a simplified schema of the extrapyramidal pathways and a system of classification of abnormal movements, parkinsonism/tremor, dystonia, chorea, myoclonus, and hemiballismus. Parkinsonisms are characterized by abnormalities of the cortico-ponto-cerebello-dentato-rubro-thalamo-cortico-spinal tract or the nigrostriatal tract. Dystonias are characterized by abnormalities of the neostriatum predominantly affecting the putamen. Choreas are also characterized by abnormalities of the neostriatum but predominantly affecting the caudate nucleus. Hemiballismus is characterized by lesions affecting the subthalamic nucleus or associated pathway.
This article has been cited by other articles:
![]() |
D. Dormont, K. G. Ricciardi, D. Tande, K. Parain, C. Menuel, D. Galanaud, S. Navarro, P. Cornu, Y. Agid, and J. Yelnik Is the Subthalamic Nucleus Hypointense on T2-Weighted Images? A Correlation Study Using MR Imaging and Stereotactic Atlas Data AJNR Am. J. Neuroradiol., October 1, 2004; 25(9): 1516 - 1523. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Bartzokis, D. Sultzer, J. Cummings, L. E. Holt, D. B. Hance, V. W. Henderson, and J. Mintz In Vivo Evaluation of Brain Iron in Alzheimer Disease Using Magnetic Resonance Imaging Arch Gen Psychiatry, January 1, 2000; 57(1): 47 - 53. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Melberg, N. Dahl, J. Hetta, S. Valind, I. Nennesmo, P. O. Lundberg, and R. Raininko Neuroimaging study in autosomal dominant cerebellar ataxia, deafness, and narcolepsy Neurology, December 1, 1999; 53(9): 2190 - 2190. [Abstract] [Full Text] |
||||
![]() |
P. D. Griffiths, B. R. Dobson, G. R. Jones, and D. T. Clarke Iron in the basal ganglia in Parkinson's disease: An in vitro study using extended X-ray absorption fine structure and cryo-electron microscopy Brain, April 1, 1999; 122(4): 667 - 673. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Kraft, J. Schwarz, C. Trenkwalder, T. Vogl, T. Pfluger, and W. H. Oertel The Combination of Hypointense and Hyperintense Signal Changes on T2-Weighted Magnetic Resonance Imaging Sequences: A Specific Marker of Multiple System Atrophy? Arch Neurol, February 1, 1999; 56(2): 225 - 228. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |