Diffusion tensor imaging correlates with lesion volume in cerebral hemisphere infarctions

Abstract

BackgroundBoth a large lesion volume and abnormalities in diffusion tensor imaging are independently associated with a poor prognosis after cerebral infarctions. Therefore, we assume that they are associated. This study assessed the associations between lesion volumes and diffusion tensor imaging in patients with a right-sided cerebral infarction.MethodsThe lesion volumes of 33 patients (age 65.9 ± 8.7, 26 males and 7 females) were imaged using computed tomography (CT) in the acute phase (within 3-4 hours) and magnetic resonance imaging (MRI) in the chronic phase (follow-up at 12 months, with a range of 8-27 months). The chronic-phase fractional anisotropy (FA) and mean diffusivity (MD) values were measured at the site of the infarct and selected white matter tracts. Neurological tests in both the acute and chronic phases, and DTI lateralization were assessed with the Wilcoxon signed-rank test. The effects of thrombolytic therapy (n = 10) were assessed with the Mann-Whitney U test. The correlations between the measured parameters were analysed with Spearman's rho correlation. Bonferroni post-hoc correction was used to compensate for the familywise error rate in multiple comparisons.ResultsSeveral MD values in the right hemisphere correlated positively and FA values negatively with the lesion volumes. These correlations included both lesion area and healthy tissue. The results of the mini-mental state examination and the National Institutes of Health Stroke Scale also correlated with the lesion volume.ConclusionsA larger infarct volume is associated with more pronounced tissue modifications in the chronic stage as observed with the MD and FA alterations.

Diffusion tensor imaging with direct cytopathological validation: characterisation of decorin treatment in experimental juvenile communicating hydrocephalus

“…Commonly used scalar DTI parameters such as axial (AD), radial (RD), and mean diffusivities (MD) (equivalent to the speed of motion in the principal axes of diffusion) or the fractional anisotropy (FA) (equivalent to a normalized aspect ratio of the principal axes of diffusion) have been useful in the investigation of cerebral abnormalities; an increase in the AD, RD and MD alongside a decrease in the FA occurs in the cerebral white matter of children with hydrocephalus [ 29 – 33 ]. Furthermore, the specificity of DTI to act as a surrogate measure of cerebral pathology has been highlighted in a variety of conditions, including hypoxic ischaemic injury [ 34 , 35 ], multiple sclerosis [ 36 – 39 ], spinal cord injury [ 40 ], obstructive hydrocephalus [ 41 ], temporal lobe epilepsy [ 42 , 43 ] and for delineating gliomas [ 44 ]. However, correlations between DTI parameters and underlying cytopathology in communicating hydrocephalus have yet to be determined (Appendix 1 ).…”

Repeatability and variation of region-of-interest methods using quantitative diffusion tensor MR imaging of the brain

“…FA and ADC changes have been found in several white matter diseases [12-16], but it is known that age affects both FA and ADC values, and small changes occur across the lifespan and even in different ways with men and women [17]. …”

Transhemispheric Diaschisis after Unilateral Focal Cerebral Ischemia Reperfusion: A Longitudinal Voxel-Based Study by MRI

“…DTI, on the other hand, becomes more accurate in in vivo estimates of cerebral tissue microstructures [20]. The use of MRI acquired water diffusion parameters such as FA (a measure of directional water diffusion) and MD (a measure of mean diffusivity of water, a surrogate marker of cerebral edema) have become popular in cerebral ischemia injury assessment [40][41][42][43]. Each of these imaging techniques has been used to study ischemic stroke, however, the use of both imaging techniques as a multi-modal imaging approach is considered to be more effective in the characterization of cerebral ischemia [44].…”