Validation of diffusion tensor MRI-based muscle fiber tracking.
Diffusion-tensor (DT) MRI fiber tracking may potentially be used for in vivo structural analysis. The purpose of this study was to assess quantitatively the ability of a DT-MRI fiber-tracking algorithm to measure the fiber orientation (pennation) in skeletal muscle in vivo. In five adult Sprague-Dawley rats, the pennation angle (theta) was measured in the rat lateral gastrocnemius with DT-MRI (theta(DT-MRI)) and by direct anatomical inspection (DAI) (theta(DAI)). The mean theta(DT-MRI) was not significantly different from the mean theta(DAI). In addition, the two methods were highly correlated (r = 0.89) and the regression of theta(DT-MRI) on theta(DAI) resulted in a slope not significantly different from 1 and an intercept not significantly different from zero. These data indicate that DT-MRI-based fiber tracking as implemented here is a valid tool for in vivo structural analysis of small-animal skeletal muscle.
Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut 06520-8042, USA. bdamon@boreas.med.yale.edu
Bruce M
BM
Damon
Zhaohua
Z
Ding
Adam W
AW
Anderson
Andrea S
AS
Freyer
John C
JC
Gore
D000818:Animals; D008279:Magnetic Resonance Imaging / Q000379:methods*; D018485:Muscle Fibers, Skeletal / Q000166:cytology*; D018482:Muscle, Skeletal / Q000166:cytology*; D051381:Rats; D017207:Rats, Sprague-Dawley