Diagnostic Accuracy of High-Resolution 3D T2-SPACE in Detecting Cerebral Venous Sinus Thrombosis.

BACKGROUND AND PURPOSE: Assessment of cerebral venous sinus thrombosis on MR imaging can be challenging. The aim of this study was to evaluate the diagnostic accuracy of high-resolution 3D T2 sampling perfection with application-optimized contrasts by using different flip angle evolution (SPACE) in patients with cerebral venous sinus thrombosis and to compare its performance with contrast-enhanced 3D T1-MPRAGE. MATERIALS AND METHODS: We performed a blinded retrospective analysis of T2-SPACE and contrast-enhanced MPRAGE sequences from patients with cerebral venous sinus thrombosis and a control group. The results were compared with a reference standard, which was based on all available sequences and clinical history. Subanalyses were performed according to the venous segment involved and the clinical stage of the thrombus. RESULTS: Sixty-three MR imaging examinations from 35 patients with cerebral venous sinus thrombosis and 51 examinations from 40 control subjects were included. The accuracy, sensitivity, and specificity calculated from the initial MR imaging examination for each patient were 100% each for T2-SPACE and 95%, 91%, and 98%, respectively, for contrast-enhanced MPRAGE. The interrater reliability was high for both sequences. In the subanalysis, the accuracy for each venous segment involved and if subdivided according to the clinical stage of thrombus was ≥95% and ≥85% for T2-SPACE and contrast-enhanced MPRAGE, respectively. CONCLUSIONS: Both T2-SPACE and contrast-enhanced MPRAGE offer high accuracy for the detection and exclusion of cerebral venous sinus thrombosis; however, T2-SPACE showed a better overall performance and thus could be a useful tool if included in a multiparametric MR imaging protocol for the diagnosis of cerebral venous sinus thrombosis, especially in scenarios where gadolinium administration is contraindicated.

Author Correction: Post-stroke insomnia in community-dwelling patients with chronic motor stroke: Physiological evidence and implications for stroke care.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Post-stroke insomnia in community-dwelling patients with chronic motor stroke: Physiological evidence and implications for stroke care.

Questionnaire studies suggest that stroke patients experience sustained problems with sleep and daytime sleepiness, but physiological sleep studies focussing specifically on the chronic phase of stroke are lacking. Here we report for the first time physiological data of sleep and daytime sleepiness obtained through the two gold-standard methods, nocturnal polysomnography and the Multiple Sleep Latency Test. Data from community-dwelling patients with chronic right-hemispheric stroke (>12 months) were compared to sex- and age-matched controls. Behavioural and physiological measures suggested that stroke patients had poorer sleep with longer sleep latencies and lower sleep efficiency. Patients further spent more time awake during the night, and showed greater high-frequency power during nonREM sleep than controls. At the same time the Multiple Sleep Latency Test revealed greater wake efficiency in patients than controls. Importantly these findings were not due to group differences in sleep disordered breathing or periodic limb movements. Post-stroke insomnia is presently not adequately addressed within the care pathway for stroke. A holistic approach to rehabilitation and care provision, that includes targeted sleep interventions, is likely to enhance long-term outcome and quality of live in those living with chronic deficits after stroke.

Neural correlates of visuospatial bias in patients with left hemisphere stroke: a causal functional contribution analysis based on game theory.

Stroke patients frequently display spatial neglect, an inability to report, or respond to, relevant stimuli in the contralesional space. Although this syndrome is widely considered to result from the dysfunction of a large-scale attention network, the individual contributions of damaged grey and white matter regions to neglect are still being disputed. Moreover, while the neuroanatomy of neglect in right hemispheric lesions is well studied, the contributions of left hemispheric brain regions to visuospatial processing are less well understood. To address this question, 128 left hemisphere acute stroke patients were investigated with respect to left- and rightward spatial biases measured as severity of deviation in the line bisection test and as Center of Cancellation (CoC) in the Bells Test. Causal functional contributions and interactions of nine predefined grey and white matter regions of interest in visuospatial processing were assessed using Multi-perturbation Shapley value Analysis (MSA). MSA, an inference approach based on game theory, constitutes a robust and exact multivariate mathematical method for inferring functional contributions from multi-lesion patterns. According to the analysis of performance in the Bells test, leftward attentional bias (contralesional deficit) was associated with contributions of the left superior temporal gyrus and rightward attentional bias with contributions of the left inferior parietal lobe, whereas the arcuate fascicle was contributed to both contra- and ipsilesional bias. Leftward and rightward deviations in the line bisection test were related to contributions of the superior longitudinal fascicle and the inferior parietal lobe, correspondingly. Thus, Bells test and line bisection tests, as well as ipsi- and contralesional attentional biases in these tests, have distinct neural correlates. Our findings demonstrate the contribution of different grey and white matter structures to contra- and ipsilesional spatial biases as revealed by left hemisphere stroke. The results provide new insights into the role of the left hemisphere in visuospatial processing.

[Functional neuroimaging of neglect]. / Funktionelle Bildgebung des Neglekts.

Though the neglect syndrome is often observed in clinical practice, there are few studies investigating its mechanisms or developing new therapeutic approaches. Most studies on attention were conducted in healthy subjects. In this paper I provide functional neuroimaging data about functional networks for stimuli perception independently from their modality. Additionally, the restoration of stimulus perception and its modulation through emotion are discussed.

[Diffusion- and perfusion-weighted magnetic resonance imaging: possibilities and perspectives].

The article addresses theoretical and practical issues of using diffusion- (DW-MRI) and perfusion-weighted (PW-MRI) magnetic resonance tomography in acute period of ischemic stroke. The authors consider prognostic value of the results obtained with both methods of MRI-diagnosis and possibilities of their usage in pathophysiological studies of ischemic stroke. Prognostic value of DW-MRI in measuring of final size of stroke used at the first day of stroke is higher compared to standard regimes. A ratio between clinical and MRI data has been analyzed. A conception comparing a ratio between the presence of lesion and its size using DW-MRI and PW-MRI is presented. A longer duration of the penumbra comparing to conventional terms was described. The results of DW-MRI and PW-MRI study are suggested to be used for prognostic purpose as well as for elaboration of an optimal treatment tactics. Some controversial issues of using DW-MRI and PW-MRI, are discussed.

[Neuromuscular electrostimulation in acute ischemic stroke].

Efficacy of poststroke rehabilitation depends on intensity of afferent current from the paretic limb to the lesion. The afferentation course is represented by neuromuscular electrostimulation (NMES) of the paretic hand's finger and hand extensors. The procedure's effect on the focus of acute ischemic lesion was analysed with MRT imaging including diffusion-perfusion-weighted MRT which can assess bioenergetic condition of the focus and brain perfusion. The analysis shows that NMES in acute ischemic stroke does not result in enlargement of the lesion and deterioration of brain circulation. Motor function seems to recover faster in the group given NMES.