Changes in Fiber Integrity, Diffusivity, and Metabolism of the Pyramidal Tract Adjacent to Gliomas: A Quantitative Diffusion Tensor Fiber Tracking and MR Spectroscopic Imaging Study
A. Stadlbauera,
C. Nimskya,
S. Gruberd,e,
E. Moserd,e,
T. Hammenb,
T. Engelhornc,
M. Buchfeldera and
O. Ganslandta
a Department of Neurosurgery, University of Erlangen-Nuremberg, Germany
b Department of Neurology, University of Erlangen-Nuremberg, Germany
c Department of Neuroradiology, University of Erlangen-Nuremberg, Germany
d MR Center of Excellence, Medical University of Vienna, Austria
e Department of Diagnostic-Radiology, Medical University of Vienna, Austria
View larger version (60K):
[in this window]
[in a new window]
|
Fig 1. Results of the fiber-tracking procedure of the DTI data and the spectral analysis of the MRSI data for a patient having no sensorimotor deficits (patient 17 in Table 1). Screenshot from the planning workstation of a navigation system of an axial T2-weighted MR imaging (A) coregistered with a segmented metabolic Cho/NAA map (C). Overlaid on these images are the cross sections of the ipsilateral (blue) and contralateral (magenta) pyramidal tracts, the tumor segmented manually by a neurosurgeron (yellow), and the VOI (PRESS-box) of the MRSI experiment (white rectangle).
B, a 3D reconstruction of the ipsilateral (blue) and contralateral (magenta) pyramidal tracts depicted on the axial sections of the DTI dataset measured with a b-value = 0 s/mm2. LCModel fits (red line) of the MRSI data of voxel position 1 (D) and 2 (E) as depicted in C as white squares. Overlaid on these images are the molar concentrations for Cho, Cr, and NAA calculated by LCModel.
| |
View larger version (59K):
[in this window]
[in a new window]
|
Fig 2. Results of the fiber-tracking procedure of the DTI data and the spectral analysis of the MRSI data for a patient with a hypesthesia in right arm (patient 14 in Table 1). Screenshot from the planning workstation of a navigation system of an axial T2-weighted MR imaging (A) coregistred with a segmented metabolic Cho/NAA map (C). Overlaid on these images are the cross sections of the ipsilateral (blue) and contralateral (magenta) pyramidal tracts, the tumor segmented manually by a neurosurgeon (green), and the PRESS-box of the MRSI experiment (white rectangle).
B, a 3D reconstruction of the ipsilateral (blue) and contralateral (magenta) pyramidal tracts depicted on the axial sections of the DTI dataset measured with a b-value = 0 s/mm2. LCModel fits (red line) of the MRSI data of voxel positions 1 (D) and 2 (E) as depicted in C as white squares. Overlaid on these images are the molar concentrations for Cho, Cr, and NAA calculated by LCModel.
| |
View larger version (14K):
[in this window]
[in a new window]
|
Fig 3. Shown are boxplots of FpV, FA, and MD values of the whole ipsilateral and contralateral pyramidal tracts (A, B, and C, respectively). The horizontal lines are the medians, and the ends of the boxes are the lower and upper quartiles (25th and 75th percentiles). MD values are expressed in units x 10–3 mm2/s. The error bars depict the SD. Overlaid are the P values calculated from a 2-sided paired t test (ns = not significant).
| |
View larger version (30K):
[in this window]
[in a new window]
|
Fig 4. Shown are boxplots of FpV, FA, and MD values for the section of the ipsilateral and contralateral pyramidal tracts (A, B, and C, respectively) corresponding with the MRSI section, respectively. Boxplots of molar concentrations of NAA, Cho, and the Cho/NAA ratio averaged over voxel positions located at the ipsilateral and contralateral pyramidal tract cross sections (D, E, and F, respectively). MD values are expressed in units x 10–3 mm2/s. NAA and Cho values are are expressed in millimoles per liter. Overlaid are the P values calculated from a 2-sided paired t test.
| |
View larger version (15K):
[in this window]
[in a new window]
|
Fig 5. Boxplots of FpV, FA, and MD values of the section of the ipsilateral pyramidal tracts corresponding with the MRSI section for subgroups of patients without sensorimotor deficits, "no," and patients with sensorimotor deficits, "yes" (A, B, and C, respectively). MD values are expressed in units x 10–3 mm2/s. Overlaid are the P values calculated from a 2-sided unpaired t test (ns = not significant).
| |
