Diffusion tensor imaging correlates with lesion volume in cerebral hemisphere infarctions

The 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.Several 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.A larger infarct volume is associated with more pronounced tissue modifications in the chronic stage as observed with the MD and FA alterations.Patients with a right-sided cerebral infarction and attention deficits are known to have a worse functional outcome in comparison to patients with a left-sided infarction [1,2]. However, the anatomical correlate of an attention deficit is still uncertain and associated with both the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) [3]. Patients with cerebral artery infarctions and attention deficits have disconnections both between and within hemispheres [3,4].Diffusion tensor imaging (DTI) of stroke patients is an important imaging method in radiological research, representing a useful tool when conventional imaging methods are insufficient. DTI parameters have be