Motor Vehicle Collision Involvement among Persons with Hemianopia and Quadrantanopia

Vision-related quality of life after unilateral occipital stroke

BACKGROUND/OBJECTIVES

Stroke damage to the primary visual cortex induces large, homonymous visual field defects that impair daily living. Here, we asked if vision-related quality of life (VR-QoL) is impacted by time since stroke.

SUBJECTS/METHODS

We conducted a retrospective meta-analysis of 95 occipital stroke patients (female/male = 26/69, 27-78 years old, 0.5-373.5 months poststroke) in whom VR-QoL was estimated using the National Eye Institute Visual Functioning Questionnaire (NEI-VFQ) and its 10-item neuro-ophthalmic supplement (Neuro10). Visual deficit severity was represented by the perimetric mean deviation (PMD) calculated from 24-2 Humphrey visual fields. Data were compared with published cohorts of visually intact controls. The relationship between VR-QoL and time poststroke was assessed across participants, adjusting for deficit severity and age with a multiple linear regression analysis.

RESULTS

Occipital stroke patients had significantly lower NEI-VFQ and Neuro10 composite scores than controls. All subscale scores describing specific aspects of visual ability and functioning were impaired except for ocular pain and general health, which did not differ significantly from controls. Surprisingly, visual deficit severity was not correlated with either composite score, both of which increased with time poststroke, even when adjusting for PMD and age.

CONCLUSIONS

VR-QoL appears to improve with time postoccipital stroke, irrespective of visual deficit size or patient age at insult. This may reflect the natural development of compensatory strategies and lifestyle adjustments. Thus, future studies examining the impact of rehabilitation on daily living in this patient population should consider the possibility that their VR-QoL may change gradually over time, even without therapeutic intervention.

The effects of rehabilitative interventions on reading disorders caused by homonymous visual field defects: a meta-analysis focusing on improvement in reading speed

INTRODUCTION

Reading disorders caused by homonymous visual field defects (HVFDs) have a significant impact on a patient's quality of life. However, no review has been conducted to evaluate the available evidence on the effects of rehabilitative interventions on reading disorders caused by HVFDs. Thus, the aim of this study was to systematically evaluate the effects of rehabilitative interventions on reading disorders caused by HVFDs.

METHODS

We searched the MEDLINE/PubMed, Cochrane Library, ClinicalTrials.gov, CINAHL, and ScienceDirect databases for relevant articles. Relevant search terms were used to identify reports of randomized controlled trials or randomized crossover trials published between January 1990 and December 2021. Only studies that included reading-speed-related outcomes were analyzed. Risk of bias was assessed using the PEDro scale. Meta-analysis was conducted using a random-effects model, and standardized mean differences (SMD) and 95% confidence intervals (CIs) were calculated. Heterogeneity was assessed using the Ι2 statistic.

RESULTS

Nine studies were included in the meta-analysis. The results showed that rehabilitative interventions significantly improved reading disorders caused by HVFDs (SMD = 0.30; 95% CI 0.08-0.51; P < 0.01; Ι2 = 0.0%). Subgroup analysis showed that reading training significantly improved reading disorders (SMD = 0.35; 95% CI 0.05-0.66; P = 0.02; Ι2 = 0.0%).

CONCLUSION

Reading disorders caused by HVFDs can be improved through rehabilitation. In addition, reading training for the improvement of eye movement and fixation to compensate for foveal and parafoveal visual field defects may improve reading speed.

Perceptual-Cognitive Integration for Goal-Directed Action in Naturalistic Environments

Real-world actions require one to simultaneously perceive, think, and act on the surrounding world, requiring the integration of (bottom-up) sensory information and (top-down) cognitive and motor signals. Studying these processes involves the intellectual challenge of cutting across traditional neuroscience silos, and the technical challenge of recording data in uncontrolled natural environments. However, recent advances in techniques, such as neuroimaging, virtual reality, and motion tracking, allow one to address these issues in naturalistic environments for both healthy participants and clinical populations. In this review, we survey six topics in which naturalistic approaches have advanced both our fundamental understanding of brain function and how neurologic deficits influence goal-directed, coordinated action in naturalistic environments. The first part conveys fundamental neuroscience mechanisms related to visuospatial coding for action, adaptive eye-hand coordination, and visuomotor integration for manual interception. The second part discusses applications of such knowledge to neurologic deficits, specifically, steering in the presence of cortical blindness, impact of stroke on visual-proprioceptive integration, and impact of visual search and working memory deficits. This translational approach-extending knowledge from lab to rehab-provides new insights into the complex interplay between perceptual, motor, and cognitive control in naturalistic tasks that are relevant for both basic and clinical research.

Impact of vision disorders and vision impairment on motor vehicle crash risk and on-road driving performance: A systematic review

Vision is important for safe driving, but there is limited understanding regarding the impact of vision disorders on driving ability and safety. This systematic review evaluated and summarized evidence on the impact of vision disorders and impairment on motor vehicle crash (MVC) risk and on-road driving performance across seven databases, was prospectively registered with PROSPERO (CRD42020180135), and study quality rated using a standard tool. Forty-eight studies met the inclusion criteria for MVC risk (N = 36), on-road performance (N = 9), and both MVC risk and on-road performance (N = 3). Of these studies, less than half were rated as 'good' quality. Due to the small number of studies and often conflicting findings, it was not possible to draw firm conclusions for most vision disorders. However, evidence from several 'good' and 'fair' quality studies suggested increased MVC risk with binocular visual field impairment. There was mixed evidence regarding the impact of cataract, glaucoma, age-related macular degeneration and homonymous field loss on MVC risk and no evidence of increased MVC risk with mild VA impairment. This review highlights the need for well-designed future studies to further explore the impact of vision disorders and impairment on driving outcomes to inform evidence-based policy and fitness to drive guidelines.

The effects of induced optical blur on visual search performance and training

Visual search is a task often used in the rehabilitation of patients with cortical and non-cortical visual pathologies such as visual field loss. Reduced visual acuity is often comorbid with these disorders, and it remains poorly defined how low visual acuity may affect a patient’s ability to recover visual function through visual search training. The two experiments reported here investigated whether induced blurring of vision (from 6/15 to 6/60) in a neurotypical population differentially affected various types of feature search tasks, whether there is a minimal acceptable level of visual acuity required for normal search performance, and whether these factors affected the degree to which participants could improve with training. From the results, it can be seen that reducing visual acuity did reduce search speed, but only for tasks where the target was defined by shape or size (not colour), and only when acuity was worse than 6/15. Furthermore, searching behaviour was seen to improve with training in all three feature search tasks, irrespective of the degree of blurring that was induced. The improvement also generalised to a non-trained search task, indicating that an enhanced search strategy had been developed. These findings have important implications for the use of visual search as a rehabilitation aid for partial visual loss, indicating that individuals with even severe comorbid blurring should still be able to benefit from such training.