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Background: Diffusion tensor imaging (DTI) biomarkers can be used to quantify microstructural changes in the cerebral white matter (WM) following injury., Objectives: This prospective single-center study aimed to evaluate whether atlas-based DTI-derived metrics obtained within 1 week after stroke can predict the motor outcome at 3 months., Methods: Forty patients with small acute stroke (2-7 days after onset) involving the corticospinal tract were included. Each patient underwent magnetic resonance imaging (MRI) within 1 week and at 3 months after stroke, and the changes based on DTI-derived metrics were compared by performing WM tract atlas-based quantitative analysis., Results: A total of 40 patients were included, with median age 63.5 years and a majority of males (72.5%). Patients were classified into good-prognosis group (mRS 0-2, n  = 27) and poor-prognosis group (mRS 3-5, n  = 13) by outcome. The median (25 th -75 th percentile) of MD (0.7 (0.6-0.7) vs. 0.7 (0.7-0.8); p  = 0.049) and AD (0.6 (0.5, 0.7) vs. 0.7 (0.6, 0.8); p  = 0.023) ratios within 1 week were significantly lower in the poor-prognosis group compared to the good-prognosis group. The ROC curve of the combined DTI-derived metrics model showed comparable Youden index (65.5% vs. 58.4%-65.4%) and higher specificity (96.3% vs. 69.2%-88.5%) compared to clinical indexes. The area under the ROC curve of the combined DTI-derived metrics model is comparable to those of the clinical indexes (all p  > 0.1) and higher than those of the individual DTI-derived metrics parameters., Conclusions: Atlas-based DTI-derived metrics at acute stage provide objective information for prognosis prediction of patients with ischemic or lacunar stroke.

Systemic lupus erythematosus (SLE) is an autoimmune disease frequently associated with neuropsychiatric manifestations. No follow-up case report has characterized white matter alterations in patients with neuropsychiatric lupus erythematosus (NPSLE) before and after treatment. In this study, a 16-year-old NPSLE patient with severe neuropsychological symptoms was treated with steroid pulse therapy, and was scanned with conventional magnetic resonance (MR) and diffusion tensor imaging (DTI) at onset and 17months after treatment. Conventional MR images showed diffuse brain atrophy and focal vasogenic edema in the putamen, but they did not reveal abnormalities in the corpus callosum. Region-of-interest analysis of DTI images showed that fractional anisotropy and fiber tracts increased significantly, while axial diffusivity, radial, and mean diffusivity decreased significantly in the corpus callosum after treatment. The results indicated that the vasogenic edema was present in the corpus callosum at onset and was significantly reduced after treatment. These changes were generally compatible with the patient's clinical manifestations. Hence, we concluded that MR-DTI and fiber tractography are helpful to reveal the relationship between white matter alterations and neurological dysfunctions in NPSLE patients., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The pathogenetic mechanism of persistent post-concussive symptoms (PCS) following concussion remains unclear. Thalamic damage is known to play a role in PCS prolongation while the evidence and biomarkers that trigger persistent PCS have never been elucidated. We collected longitudinal neuroimaging and behavior data from patients and rodents after concussion, complemented with rodents' histological staining data, to unravel the early biomarkers of persistent PCS. Diffusion tensor imaging (DTI) were acquired to investigated the thalamic damage, while quantitative thalamocortical coherence was derived through resting-state functional MRI for evaluating thalamocortical functioning and predicting long-term behavioral outcome. Patients with prolonged symptoms showed abnormal DTI-derived indices at the boundaries of bilateral thalami (peri-thalamic regions). Both patients and rats with persistent symptoms demonstrated enhanced thalamocortical coherence between different thalamocortical circuits, which disrupted thalamocortical multifunctionality. In rodents, the persistent DTI abnormalities were validated in thalamic reticular nucleus (TRN) through immunohistochemistry, and correlated with enhanced thalamocortical coherence. Strong predictive power of these coherence biomarkers for long-term PCS was also validated using another patient cohort. Postconcussive events may begin with persistent TRN injury, followed by disrupted thalamocortical coherence and prolonged PCS. Functional MRI-based coherence measures can be surrogate biomarkers for early prediction of long-term PCS. • Thalamic reticular nucleus (TRN) injury persists up to 2 years after concussion. • Persistent postconcussive symptoms (PCS) related to elevated thalamocortical coherence. • TRN injury explains thalamocortical dysfunction and PCS prolongation. • Baseline coherence biomarkers predicts persistent PCS. [ABSTRACT FROM AUTHOR]