TABLE 3. Clinical Applications of Diffusion Tensor Imaging.
| Condition | Study | n (patients/controls) | Measure(s) | Findings* |
|---|---|---|---|---|
| Stroke | Jones et al.80 | 9/10 | Tr, FA | Decrease in anisotropy, increase in diffusivity within the lacunar infarction |
| Sorenson et al.81 | 50/0 | FA, Tr, eigenvalues of the tensor | Reduction of anisotropy within white matter in acute cerebral stroke, attributable to changes in the first and second eigenvalues (aligned with the long axes of the white matter fiber tracts) | |
| Zelaya et al.26 | 6/0 | Tr, FA, LI | Monotonic and significant decrease in anisotropy measures within the ischemic lesion from the acute to the chronic stage | |
| Mukherjee et al.29 | 12/0 | Isotropic diffusion coefficient (similar to Tr), diffusion anisotropy | More-severe reduction in diffusion measures within white matter than within gray matter in acute to early subacute stroke | |
| Werring et al.27 | 5/0 | Tr, FA | Reduced anisotropy 6 mo after cerebral infarction within the corticospinal tract, remote from the lesion | |
| Pierpaoli et al.28 | 7/0 | Tr, FA, LI | Reduced anisotropy within the entire fiber tract affected by the lacunar infarction, due to wallerian degeneration | |
| Brain injury | Werring et al.32 | 1/5 | FA | Decreased anisotropy within the anterior limb of the internal capsule, which correlated with the functional motor deficits revealed by fMRI several months after the internal capsule focal brain injury |
| Wieshmann et al.33 | 1/0 | FA, Tr | Increased diffusivity in the right frontal, temporal, and occipital lobes, as well as reduced anisotropy in the right optic radiation and forceps occipitalis, in a patient with right frontotemporal brain injury suffering from impaired memory | |
| Jones et al.82 | 5/0 | Tr | Reduced diffusivity in the periphery of a cerebral contusion despite a negative MRI | |
| Brain tumor | Bastin et al.83 | 6/0 | Tr | After dexamethasone treatment, decrease in trace within tumor and surrounding edematous tissue |
| Wieshmann et al.34 | 1/20 | FA, Tr | Deviation of fibers in normal-appearing white matter adjacent to the tumor | |
| Mori et al.35 | 2/0 | 3-dimensional fiber tracking | Displacement of the fiber tracts in one patient; infiltration without displacement in another patient | |
| Focal epilepsy | Krakow et al.84 | 1/0 | FA, Tr | Reduced anisotropy, high diffusivity, and displacement of myelinated tracts due to a malformation of cortical development was detected in a patient with focal epilepsy |
| Rugg-Gunn et al.37 | 30/30 | FA, Tr | Increased diffusivity and reduced anisotropy were noted within the white matter of the left temporal lobe in subjects with electroclinical seizure onset localized to the left temporal lobe | |
| Eriksson et al.85 | 22/30 | FA, Tr | In patients with a malformation of cortical development, reduced anisotropy and increased diffusivity were observed beyond the malformed areas | |
| MS | Werring et al.86 | 6/6 | FA, Tr | In MS patients the highest diffusivity was seen in destructive lesions, whereas the greatest change in anisotropy was found in inflammatory lesions |
| Tievsky et al.41 | 12/0 | FA, RA, E | In acute lesions, plaque centers had high ADC with reduced anisotropy compared with rims, normal-appearing white matter, and chronic lesions | |
| Nusbaum et al.87 | 13/12 | Tr | In MS patients, mean whole-brain diffusivity was elevated | |
| Castriota-Scanderbeg et al.43 | 20/11 | D | Diffusivity was greater in lesions of patients with secondary progressive MS than in those of patients with relapsing-remitting MS | |
| Bammer et al.88 | 14/9 | Tr, FA | Diffusivity was slightly but significantly greater in normal-appearing white matter in MS patients than in the white matter of controls | |
| Filippi et al.42 | 78/20 | FA, D | Normal-appearing white matter of MS patients showed higher diffusivity and lower anisotropy than did white matter of controls | |
| Alzheimer's disease | Rose et al.57 | 11/9 | LI | Patients showed lower anisotropy in the association white matter fiber tracts, such as the splenium of the corpus callosum, the superior longitudinal fasciculus, and the cingulum, than did controls |
| Kantarci et al.58 | 19/55 | AI† | ADCs of the hippocampus and the temporal stem, posterior cingulate, occipital, and parietal white matter were higher in patients than in controls | |
| Schizophrenia | Buchsbaum et al.61 | 5/6 | RA | Patients showed lower anisotropy in the white matter of the prefrontal cortex than did controls |
| Lim et al.60 | 10/10 | FA, Tr | Anisotropy was lower in the white matter of patients than in that of controls | |
| Foong et al.62 | 20/25 | FA, Tr | Compared with controls, patients showed higher diffusivity and lower anisotropy in the splenium but not the genu of the corpus callosum | |
| Agartz et al.63 | 20/24 | FA, Tr | Patients showed lower anisotropy in the splenium of the corpus callosum as well as a higher diffusivity throughout the entire volume of white matter compared to controls | |
| Steel et al.89 | 10/10 | FA | No differences in anisotropy in prefrontal white matter were observed between controls and patients | |
| Kubicki et al.64 | 15/18 | FA | Diminished left/right asymmetry in anisotropy in the uncinate fasciculus was seen in patients compared to controls | |
| Other conditions affecting white matter | ||||
| HIV infection | Pomara et al.45 | 6/9 | FA, Tr, PD | Frontal lobe and internal capsule white matter showed decreased anisotropy in patients compared to controls |
| Filippi et al.46 | 10/0 | UA, Tr | Diffusivity decreased in the corpus callosum and increased in the subcortical frontal and parietal regions in patients with elevated viral load; no changes in patients taking antiretroviral drugs | |
| Krabbe's disease | Guo et al.44 | 8/8 | RA | Patients showed lower anisotropy in white matter than did controls; following treament, anisotropy increased but was still lower than in controls |
| Chronic alcohol dependence | Pfefferbaum et al.50 | 15/31 | FA, IC | Patients showed lower anisotropy and coherence in the corpus callosum than did controls; working memory and attention measures correlated positively with anisotropy |
| ALS | Ellis et al.47 | 22/20 | FA, Tr | Anisotropy correlated with disease severity and upper motor neuron involvement; diffusivity correlated with disease duration |
| Ulug et al.49 | 4/0 | UA | No decrease of anisotropy within the corticospinal tract was detectable on MRI | |
| X-linked ALD | Ito et al.90 | 11/0 | ADC, FA | Affected areas of the white matter showed lower anisotropy than did unaffected areas; follow-up studies revealed an increase of the affected area on the FA maps, attributable to loss of myelin-sheath integrity |
| CADASIL | Chabriat et al.48 | 16/10 | VR, Tr | Patients showed increased diffusivity and decreased anisotropy both in lesions and in normal-appearing white matter compared to controls; degree of abnormality correlated with clinical severity |
ADC, apparent diffusion coefficient; AI, anisotropy index; ALD, adrenoleukodystrophy; ALS, amyotrophic lateral sclerosis; CADASIL, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy; D, averaged water diffusion coefficient; E, eccentricity; FA, fractional anisotropy; fMRI, functional magnetic resonance imaging; HIV, human immunodeficiency virus; IC, intervoxel coherence; LI, lattice index of anisotropy; MRI, magnetic resonance imaging; MS, multiple sclerosis; PD, proton density; RA, relative anisotropy; Tr, diffusion trace; UA, ultimate anisotropy; VR, volume ratio.
*
A11 findings reported are significant at p < 0.05.
†
A regional measure of the directionality of diffusion.