White matter lesions and cognitive impairment may be related to recovery from unilateral spatial neglect after stroke

Recovery of Visuospatial Neglect With Standard Treatment: A Systematic Review and Meta-Analysis

BACKGROUND

Visuospatial neglect is a common consequence of stroke and is characterized by impaired attention to contralesional space. Currently, the extent and time course of recovery from neglect are not clearly established. This systematic review and meta-analysis aimed to determine the recovery trajectory of poststroke neglect with standard treatment.

METHODS

PsycInfo, Embase, and MEDLINE were searched for articles reporting recovery rates of neglect after stroke. Time since stroke was categorized into early (0-3 months), mid (3-6 months), and late (>6 months) recovery phases. Random-effects models for pooled prevalence were generated for each phase, and potential sources of heterogeneity were explored with metaregressions. Methodological quality of each study was assessed using the Joanna Briggs Institute checklist, with low-quality studies excluded in sensitivity analyses.

RESULTS

The search captured 4130 articles including duplicates, and 111 full-text reviews were undertaken. A total of 27 studies reporting data from 839 stroke survivors with neglect were included for review. Meta-analyses indicated a recovery rate of 42% in the early phase, which increased to 53% in the mid-recovery phase. Additional recovery in the late phase was minimal, with an estimated 56% recovery rate. Heterogeneity of studies was high (I2>75%) in all 3 phases of recovery. Estimates were robust to sensitivity analyses. Metaregressions showed significantly greater recovery in studies that included patients with left-hemisphere lesions (β=0.275, P<0.05, I2=84%).

CONCLUSIONS

Most recovery from neglect occurs in the first 3 months, although additional gains can be expected up to 6 months poststroke. While a large proportion of patients recover from neglect, over 40% show persistent symptoms. Further research is needed on effective rehabilitation interventions, particularly focusing on patients most at risk of chronic visuospatial neglect.

REGISTRATION

URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42023388763.

Unilateral Spatial Neglect Recovery Poststroke

Unilateral spatial neglect (USN) is a common and disabling cognitive consequence of stroke wherein individuals demonstrate decreased response to contralesional information. Here, we provide an updated narrative review of studies that shed light on the neural mechanisms and predictors of recovery of USN. Additionally, we report a rapid review of randomized controlled trials focusing on USN intervention, both nonpharmacological and pharmacological, published in the last 5 years. Randomized controlled trials are reviewed within the context of systematic reviews and meta-analyses of USN interventions published within the same time frame. The quality of randomized controlled trials of treatment is higher compared to quality reported in previous reviews and meta-analyses. However, remaining weaknesses in participant demographic reporting, as well as small, heterogenous samples, render generalizability and cross-study interpretation a challenge. Nevertheless, evidence regarding neural mechanisms underlying USN recovery and regarding the effectiveness of targeted USN interventions is accumulating and strengthening, setting the foundation for future investigations into patient-specific factors that may influence treatment response. We identify gaps and provide suggestions for future USN intervention research.

Right hemispheric white matter hyperintensities improve the prediction of spatial neglect severity in acute stroke

White matter hyperintensities (WMH) are frequently observed in brain scans of elderly people. They are associated with an increased risk of stroke, cognitive decline, and dementia. However, it is unknown yet if measures of WMH provide information that improve the understanding of poststroke outcome compared to only state-of-the-art stereotaxic structural lesion data. We implemented high-dimensional machine learning models, based on support vector regression, to predict the severity of spatial neglect in 103 acute right hemispheric stroke patients. We found that (1) the additional information of right hemispheric or bilateral voxel-based topographic WMH extent indeed yielded a significant improvement in predicting acute neglect severity (compared to the voxel-based stroke lesion map alone). (2) Periventricular WMH appeared more relevant for prediction than deep subcortical WMH. (3) Among different measures of WMH, voxel-based maps as measures of topographic extent allowed more accurate predictions compared to the use of traditional ordinally assessed visual rating scales (Fazekas-scale, Cardiovascular Health Study-scale). In summary, topographic WMH appear to be a valuable clinical imaging biomarker for predicting the severity of cognitive deficits and bears great potential for rehabilitation guidance of acute stroke patients.

Evaluating the Potential Pathology and Short-Term Outcomes of Cryptogenic Stroke Using the Etiological Classification System

AIM

Various embolic sources and pathogenetic mechanisms underlie cryptogenic stroke (CS). We investigated the association of etiological diversity with short-term outcomes in patients with CS using a modified atherosclerosis (A), small-vessel disease (S), cardiac pathology (C), other causes (O), and dissection (D) (ASCOD) system.

METHODS

Patients with CS who underwent transesophageal echocardiography were registered in this multicenter, observational study. In the modified classification system, O and D were inapplicable and thus excluded. Instead, atherosclerosis, small-vessel disease, cardiac pathology-CS classification was specifically constructed for the etiological diagnosis of CS. We utilized this system to explore the mechanism of CS by grading each pathology and evaluated its association with poorer modified Rankin Scale scores of 3-6 at hospital discharge.

RESULTS

A total of 672 patients (68.7±12.8 years, 220 females) were analyzed. In the multiple logistic regression model, female sex (odds ratio [OR], 1.87 [1.15-3.04]; P=0.012), body mass index (OR, 0.93 [0.88-0.99]; P=0.025), National Institute of Health Stroke Scale score (OR, 1.16 [1.12-1.21]; P＜0.001), CHADS2 score (OR, 1.56 [1.30-1.86]; P＜0.001), D-dimer (OR, 1.04 [1.01-1.08]; P=0.015), diffusion-weighted image (DWI) lesion size (OR, 1.44 [1.10-1.89]; P=0.009), and S＋C score (OR, 1.26 [1.03-1.56]; P=0.029) were associated with poor functional outcome at discharge whereas the S＋C score was marginally associated with poor functional outcome after excluding 137 patients with a premorbid modified Rankin Scale score of ≥ 3.

CONCLUSIONS

The coexistence of small-vessel disease and cardiac pathology might be associated with poor in-hospital functional outcome in CS.

Lesions Responsible for Impaired Visual Perception in Poststroke Patients Using Voxel-Based Lesion Symptom Mapping

We aimed to clarify the clinical characteristics that affect visual perception (VP) and elucidate lesion locations correlated with impaired VP. We reviewed 61 patients with stroke. Clinical assessments of a motor-free VP test were used to evaluate VP after stroke. Regression analyses were performed to examine predictors of impaired VP. We generated statistical maps of lesions related to impaired VP using voxel-based lesion symptom mapping (VLSM). The group of patients who had right hemispheric lesions had significantly low VP function. In a regression model, impaired VP was predicted by cognitive function, age, lesion volume, and right hemispheric lesion. Using VLSM, we found lesion location associated with impaired VP after adjusting for age, lesion volume, and Korean version of mini mental status exam. The results showed a lesion pattern with predominant distribution in the right parietal lobe and deep white matter. Age, lesion volume, and cognitive impairment affected the results of VP tests. Even after adjustments, we found that lesions responsible for impaired VP were located in the right parietal lobe and deep white matter. This result confirmed right hemispheric dominance for VP using VLSM. Clin. Anat. 32:689-696, 2019. © 2019 Wiley Periodicals, Inc.