Neglect and aphasia in the acute phase as predictors of functional outcome 7 years after ischemic stroke

Changes in White Matter Microstructure Over 3 Years in People With and Without Stroke

BACKGROUND AND OBJECTIVES

Cerebral white matter health can be estimated by MRI-derived indices of microstructure. White matter dysfunction is increasingly recognized as a contributor to neurodegenerative disorders affecting cognition and to functional outcomes after stroke. Reduced indices of white matter microstructure have been demonstrated cross-sectionally in stroke survivors compared with stroke-free participants, but longitudinal changes in the structure of white matter after stroke remain largely unexplored. We aimed to characterize white matter micro- and macrostructure over 3 years after stroke and study associations with white matter metrics and cognitive functions.

METHODS

Patients with first-ever or recurrent ischemic stroke of any etiology in any vascular territory were compared with stroke-free age- and sex-matched controls. Those diagnosed with hemorrhagic stroke, TIA, venous infarction, or significant medical comorbidities, psychiatric and neurodegenerative disorders, substance abuse, or history of dementia were excluded. Diffusion-weighted MRI data at 3, 12, and 36 months were analyzed using a longitudinal fixel-based analysis, sensitive to fiber tract-specific differences within a voxel. It was used to examine whole-brain white matter degeneration in stroke compared with control participants. We studied microstructural differences in fiber density and macrostructural changes in fiber-bundle cross-section, in relation to cognitive performance. Analyses were performed controlling for age, intracranial volume, and education (family-wise error-corrected p < 0.05, nonparametric testing over 5,000 permutations).

RESULTS

We included 71 participants with stroke (age 66 ± 12 years, 22 women) and 36 controls (age 69 ± 5 years, 13 women). We observed extensive white matter structural degeneration across the whole brain, particularly affecting the thalamic, cerebellar, striatal, and superior longitudinal tracts and corpus callosum. Importantly, follow-up regression analyses in 72 predefined tracts showed that the decline in fiber density and cross-section from 3 months to 3 years was associated with worse cognitive performance at 3 years after stroke, especially affecting visuospatial processing, processing speed, language, and recognition memory.

DISCUSSION

We conclude that white matter neurodegeneration in ipsi- and contralesional thalamic, striatal, and cerebellar tracts continues to be greater in stroke survivors compared with stroke-free controls. White matter degeneration persists even years after stroke and is associated with poststroke cognitive impairment.

TRIAL REGISTRATION INFORMATION

ClinicalTrails.gov NCT02205424.

Mirror therapy for unilateral neglect after stroke: A systematic review

BACKGROUND AND PURPOSE

The effect of mirror therapy for unilateral neglect after stroke currently remains uncertain.

METHODS

This systematic review investigated the effect of mirror therapy on neglect and daily living activities in patients with unilateral neglect after stroke when compared with no treatment, sham mirror therapy, or routinely applied therapies only. We performed a systematic electronic search of PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure, and Wanfang Data to identify relevant randomized control trials (RCTs).

RESULTS

We included five RCTs in the data synthesis. Mirror therapy (combined or not with other treatments) was more effective in improving neglect as compared with sham mirror therapy or no treatment (combined or not with the other therapies; standard mean difference [SMD] = 1.62, 95% confidence interval [CI] = 1.03-2.21, p < 0.00001). Mirror therapy (combined or not with other therapies) was effective in improving daily living activities as compared with sham mirror therapy or no treatment (combined or not with the other therapies; SMD = 2.09, 95% CI = 0.63-3.56, p = 0.005).

CONCLUSIONS

Our results show that mirror therapy effectively improves neglect and daily living activities in patients with unilateral neglect after stroke. Future trials with high methodological quality and larger sample sizes are needed to determine the immediate and long-term effect of appropriate mirror therapy protocol for unilateral neglect.

Bedside video-oculographic evaluation of eye movements in acute supratentorial stroke patients: A potential biomarker for hemispatial neglect

BACKGROUND AND PURPOSE

The presence of hemispatial neglect adversely affects functional outcomes in stroke patients; consequently, it warrants early targeted rehabilitative intervention. Nevertheless, hemispatial neglect in the acute phase of stroke has often been underdiagnosed. In this study, we aimed to detect hemispatial neglect at the bedside in acute stroke patients by measuring eye movements using video-oculography (VOG).

METHODS

Forty-seven patients with acute unilateral supratentorial stroke were enrolled. We quantitatively measured horizontal saccade (latency, velocity, and amplitude) and smooth pursuit (gain) at the bedside using VOG and compared these variables with scores on the Behavioral Inattention Test (BIT), a screening battery to assess hemispatial neglect.

RESULTS

Contralesional saccade latency, velocity, and amplitude, and ipsilesional smooth pursuit gain were suppressed compared with those in the opposite directions (p = 0.08, 0.02, 0.04, and 0.02, respectively). These directional ocular hypokinesia values correlated with the total BIT score (correlation coefficients -0.53, 0.48, 0.51, and 0.39, respectively). The association was significant even after adjusting for age and stroke severity.

CONCLUSIONS

Eye movement measurements performed using VOG significantly correlated with the tendency for hemispatial neglect in acute supratentorial stroke patients. Bedside VOG measurement may be a simple biomarker for detecting hemispatial neglect even in patients in the supine position during the acute phase of stroke.

Poststroke Cognitive Impairment Negatively Impacts Activity and Participation Outcomes: A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aimed to investigate whether cognition is associated with activity and participation outcomes in adult stroke survivors. Five databases were systematically searched for studies investigating the relationship between general- and domain-specific cognition and longer-term (>3 months) basic activities of daily living (ADL), instrumental ADLs, and participation outcomes. Eligibility for inclusion, data extraction, and study quality was evaluated by 2 reviewers using a standardized protocol. Effect sizes (r) were estimated using a random-effects model. Sixty-two publications were retained for review, comprising 7817 stroke survivors (median age 63.57 years, range:18-96 years). Median length of follow-up was 12 months (range: 3 months-11 years). Cognition (all domains combined) demonstrated a significant medium association with all 3 functional outcomes combined, r=0.37 (95% CI, 0.33-0.41), P<0.001. Moderator analyses revealed these effects persisted regardless of study quality, order in which outcomes were collected (sequential versus concurrent), age, sample size, or follow-up period. Small to medium associations were also identified between each individual cognitive domain and the separate ADL, instrumental ADL, and participation outcomes. In conclusion, poststroke cognitive impairment is associated with early and enduring activity limitations and participation restrictions, and the association is robust to study design factors, such as sample size, participant age, follow-up period, or study quality. Cognitive assessment early poststroke is recommended to facilitate early detection of disability, prediction of functional outcomes, and to inform tailored rehabilitation therapies.

Feasibility of a minimal dataset for adults with acquired brain injury in Dutch healthcare practice

Objective

Data collection in the field of acquired brain injury (ABI) lacks uniformity due to the broad spectrum of available measurement instruments, leading to incomparability of data and the need for patients to ‘repeat their story’. To pursue uniform data collection, an ABI-specific minimal dataset (MDS-ABI) is currently under development. The current study aimed to assess the feasibility (performance according to protocol, user opinion, potential implementation barriers, and suggested improvements) of the MDS-ABI in clinical settings.

Methods

A mixed-methods approach was used in a range of healthcare sectors for persons with ABI. Clinicians of several relevant disciplines within these sectors were asked to administer the MDS-ABI to five patients. Subsequently, feasibility according to clinicians was assessed by means of a paper questionnaire about every administration and an online questionnaire about the feasibility in general. Feasibility according to patients was assessed with a paper questionnaire and think aloud interviews.

Results

Thirteen clinicians and 50 patients were included. In general, the MDS-ABI performed according to protocol. Both clinicians and patients were overall satisfied with the content of the MDS-ABI. The Cumulative Illness Rating Scale was regarded incomprehensible, leading to missing data. Further, clinicians indicated that the MDS-ABI would not be suitable for all ABI-patients, as some are incapable of self-report due to potential cognitive problems, communicative problems, fatigue, perceptual problems, or impaired awareness of deficits.

Conclusion

The MDS-ABI is a promising tool for obtaining core information on ABI-patients. The MDS-ABI will be adjusted according to the suggestions. For patients who are incapable of self-report, a proxy-reported version of the self-reported part was developed.

Modulating functional connectivity after stroke with neurofeedback: Effect on motor deficits in a controlled cross-over study

Synchronization of neural activity as measured with functional connectivity (FC) is increasingly used to study the neural basis of brain disease and to develop new treatment targets. However, solid evidence for a causal role of FC in disease and therapy is lacking. Here, we manipulated FC of the ipsilesional primary motor cortex in ten chronic human stroke patients through brain-computer interface technology with visual neurofeedback. We conducted a double-blind controlled crossover study to test whether manipulation of FC through neurofeedback had a behavioral effect on motor performance. Patients succeeded in increasing FC in the motor cortex. This led to improvement in motor function that was significantly greater than during neurofeedback training of a control brain area and proportional to the degree of FC enhancement. This result provides evidence that FC has a causal role in neurological function and that it can be effectively targeted with therapy.

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Stroke patients participated in clinical trial on neurofeedback of functional connectivity.

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Patients learned to enhance synchrony of neural activity in their motor cortex.

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This led to reduced motor impairment.

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Evidence for a causal role of neural synchrony in neurological deficits and recovery.