Advanced

AJNR - American Journal of Neuroradiology

This Article Abstract Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Huisman, T. A.G.M. Articles by Sorensen, A. G. Search for Related Content PubMed PubMed Citation Articles by Huisman, T. A.G.M. Articles by Sorensen, A. G.

Diffusion Tensor Imaging as Potential Biomarker of White Matter Injury in Diffuse Axonal Injury

Thierry A.G.M. Huisman^a,d, Lee H. Schwamm^b, Pamela W. Schaefer^c, Walter J. Koroshetz^b, Neetha Shetty-Alva^a, Yelda Ozsunar, Ona Wu^a and A. Gregory Sorensen^a

^a MGH-NMR Center, Division of Neuroradiology, Massachusetts General Hospital and Harvard Medical School, Boston
^b Department of Neurology, Division of Neuroradiology, Massachusetts General Hospital and Harvard Medical School, Boston
^c Department of Radiology, Division of Neuroradiology, Massachusetts General Hospital and Harvard Medical School, Boston
^d Department of Radiology, University Children’s Hospital Zurich, Zurich, Switzerland

View larger version (76K): [in a new window]   FIG 1. Axial FA map (left) and color coded map of mean diffusion direction (right) at the level of the basal ganglia, thalami and internal capsulae in a healthy control subject. Left, Gray-scale FA map displays a high degree of anisotropic diffusion (bright) within the internal capsule and the splenium of the corpus callosum. The cortex and the central gray matter are dark because of their low degree of anisotropic diffusion. Right, Color-coded image displays a predominant left-right-left mean diffusion direction (red) within the center of the splenium of the corpus callosum, an anteroposterior direction (green) within the optic radiations, and a superior-inferior direction (blue) within the posterior internal capsule.

View larger version (76K): [in a new window]   FIG 2. Images in a 24-year-old man with severe TBI. Acute GCS, 5. Rankin score at discharge, 3. Left, FA map shows a reduced FA index of the splenium of the corpus callosum (FA = 0.511 ± 0.036, mean control FA = 0.808 ± 0.060) and internal capsule (FA = 0.531 ± 0.036, mean control FA = 0.735 ± 0.066). Right, Color-coded map shows that, within the center of the splenium of the corpus callosum, the normally predominant red voxels are missing and replaced by a mixture of blue and green voxels (compare with Fig 1). This finding suggests that fiber tracts that connect both cerebral hemispheres are injured or disrupted within the center of the splenium.

View larger version (76K): [in a new window]   FIG 3. Images in a 37-year-old man with severe TBI. His GCS score at the time of MR imaging was 3, and his Rankin score at discharge was 4. Left, FA map shows a reduced FA index of the corpus callosum (FA = 0.634 ± 0.036). Right, Color-coded map shows a layered blue, red, and green aspect of the splenium of the corpus callosum. This could indicate a partial, selective injury of the most anterior and posterior left-right-left fiber tracts.

View larger version (33K): [in a new window]   FIG 4. Linear regression plots of ADC and FA values of the splenium and internal capsule versus GCS at the time of acute MR imaging (in patients) or at time of comparison MR imaging (control subjects, all with GCS scores of 15). A statistically significant correlation is seen between the FA values of the splenium/internal capsule and GCS, as well as between the ADC values within the splenium and GCS. GCS scores vary between 3 and 15, where 3 represents the worst score, and 15, the best score. Open rectangles indicate patients; solid rectangles, control subjects. A, ADC splenium versus GCS. B, ADC internal capsule versus GCS. C, FA splenium versus GCS. D, FA internal capsule versus GCS.

View larger version (33K): [in a new window]   FIG 5. Linear regression plots of ADC and FA values of the splenium and internal capsule versus Rankin score at the time of discharge (in patients) or at time of comparison MR imaging (control subjects, all with Rankin scores of 0). A statistically significant correlation is seen between the FA values of the splenium/internal capsule and Rankin score, as well as between the ADC values of the splenium and Rankin score. Rankin scores vary between 0 and 5, where 0 represents the best score and 5, the worst score. Open rectangles indicate patients; solid rectangles, control subjects. A, ADC splenium versus Rankin. B, ADC internal capsule versus Rankin. C, FA splenium versus Rankin. D, FA internal capsule versus Rankin.