Corticospinal tract degeneration in amyotrophic lateral sclerosis: a diffusion tensor imaging and fibre tractography study.
BACKGROUND
Motor neuron damage and cortical spinal tract (CST) degeneration in amyotrophic lateral sclerosis (ALS) are difficult to visualise and quantify on conventional magnetic resonance imaging (MRI).


METHODS
We studied 8 ALS patients and 12 normal volunteers using diffusion tensor imaging (DTI) and fibre tractography using fibre assignment by continuous tracking (FACT) to study the fibres of the CST and the posterior thalamic radiation (PTR), a nonmotor tract.


RESULTS
Fibre tractography was successfully performed in all normal volunteers and all patients except 1. The fibre bundles of the CST, but not the PTR, were significantly reduced (P <0.05) in patients compared to normal volunteers.


CONCLUSIONS
Fibre tractography can visualise axonal degeneration in the CST and may provide supplementary information about upper motor neuron disease in ALS patients.
Department of Neuroradiology, National Neuroscience Institute, Singapore.
Hong
H
Yin
Sandy H T
SH
Cheng
Jian
J
Zhang
Lin
L
Ma
Yuangui
Y
Gao
Dejun
D
Li
C C Tchoyoson
CC
Lim
D000690:Amyotrophic Lateral Sclerosis / Q000473:pathology*; D016022:Case-Control Studies; D038524:Diffusion Magnetic Resonance Imaging; D017352:Echo-Planar Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009410:Nerve Degeneration / Q000473:pathology*; D011712:Pyramidal Tracts / Q000473:pathology*