Treatment of Visual Perceptual Disorders Post Stroke

Feasibility of Computerized Visuomotor Integration System for Visual Field Defects and Spatial Neglect in Poststroke Patients

OBJECTIVE

To develop a computerized visuomotor integration system for assessment and training of visual perception impairments and evaluate its safety and feasibility in patients with a stroke. Visual field defects and spatial neglect lead to substantial poststroke impairment. Most diagnostic assessments are anchored in traditional methods, and clinical effects of rehabilitation treatments are limited.

METHODS

The CoTras Vision system included two evaluations and four training modules. The evaluation modules were based on the Albert's test and Star cancellation test, and training modules were based on visual tracking, central-peripheral integration, and visuomotor perception techniques. Bland-Altman plots for agreement with the traditional paper-and-pencil test were performed, and the modified Intrinsic Motivation Inventory, Patient Satisfaction Questionnaire, and Simulator Sickness Questionnaire were conducted.

RESULTS

Ten patients with acute stroke completed the study. Bland-Altman plots revealed good agreements for Albert's test (mean difference, -0.3±4.5) and Star cancellation test (mean difference, 0.3±0.7). The mean±standard deviation scores of the modified Intrinsic Motivation Inventory, Patient Satisfaction Survey, and Simulator Sickness Questionnaire were 84.7±30.6, 40.5±7.9, and 34.0±34.5 respectively.

CONCLUSION

The CoTras Vision system is feasible and safe in patients with stroke. Most patients had a high degree of motivation to use the system and did not experience severe adverse events. Further studies are needed to confirm its usefulness in stroke patients with visual field defects and hemineglect symptoms. Furthermore, a large, well-designed, randomized controlled trial will be needed to confirm the treatment effect of the CoTras Vision system.

Functional Connectivity Pattern Using Resting-state fMRI as an Assessment Tool for Spatial Neglect during the Recovery Stage of Stroke: A Pilot Study

PURPOSE

To determine if functional connectivity measured with resting-state functional MRI could be used as a tool to assess unilateral spatial neglect during stroke recovery.

METHODS

Resting-state functional MRI was performed on 13 stroke patients with lesions in the right cerebral hemisphere and 31 healthy subjects. The functional connectivity score was defined as a correlation of a target region with the right inferior parietal lobule. Spatial neglect was measured with a behavioral inattention test.

RESULTS

First, the functional connectivity scores between the right inferior parietal lobule and right inferior frontal gyrus, including the opercular and triangular parts, were significantly decreased in stroke patients with unilateral spatial neglect compared with patients without unilateral spatial neglect and were significantly correlated with the behavioral inattention test score. Second, the functional connectivity scores between the bilateral inferior parietal lobules were also significantly decreased in patients with unilateral spatial neglect compared with patients without unilateral spatial neglect and were significantly correlated with the behavioral inattention test score. Third, negative functional connectivity scores between the right inferior parietal lobule and bilateral medial orbitofrontal cortexes, which are related to the default mode network, were detected in patients without unilateral spatial neglect in contrast to a reduction of this negative tendency in patients with unilateral spatial neglect. The functional connectivity scores between these regions were significantly different between patients with and without unilateral spatial neglect and were negatively correlated with the behavioral inattention test score.

CONCLUSION

Though still in the pilot research stage and using a small number of cases, our findings are consistent with the hypothesis that functional connectivity maps generated with resting-state functional MRI may be used as a tool to evaluate unilateral spatial neglect during stroke recovery.

Interventions for perceptual disorders following stroke

BACKGROUND

Perception is the ability to understand information from our senses. It allows us to experience and meaningfully interact with our environment. A stroke may impair perception in up to 70% of stroke survivors, leading to distress, increased dependence on others, and poorer quality of life. Interventions to address perceptual disorders may include assessment and screening, rehabilitation, non-invasive brain stimulation, pharmacological and surgical approaches.

OBJECTIVES

To assess the effectiveness of interventions aimed at perceptual disorders after stroke compared to no intervention or control (placebo, standard care, attention control), on measures of performance in activities of daily living.  SEARCH METHODS: We searched the trials registers of the Cochrane Stroke Group, CENTRAL, MEDLINE, Embase, and three other databases to August 2021. We also searched trials and research registers, reference lists of studies, handsearched journals, and contacted authors.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of adult stroke survivors with perceptual disorders. We defined perception as the specific mental functions of recognising and interpreting sensory stimuli and included hearing, taste, touch, smell, somatosensation, and vision. Our definition of perception excluded visual field deficits, neglect/inattention, and pain.

DATA COLLECTION AND ANALYSIS

One review author assessed titles, with two review authors independently screening abstracts and full-text articles for eligibility. One review author extracted, appraised, and entered data, which were checked by a second author. We assessed risk of bias (ROB) using the ROB-1 tool, and quality of evidence using GRADE.  A stakeholder group, comprising stroke survivors, carers, and healthcare professionals, was involved in this review update.

MAIN RESULTS

We identified 18 eligible RCTs involving 541 participants. The trials addressed touch (three trials, 70 participants), somatosensory (seven trials, 196 participants) and visual perception disorders (seven trials, 225 participants), with one (50 participants) exploring mixed touch-somatosensory disorders. None addressed stroke-related hearing, taste, or smell perception disorders. All but one examined the effectiveness of rehabilitation interventions; the exception evaluated non-invasive brain stimulation. For our main comparison of active intervention versus no treatment or control, one trial reported our primary outcome of performance in activities of daily living (ADL):  Somatosensory disorders: one trial (24 participants) compared an intervention with a control intervention and reported an ADL measure.  Touch perception disorder: no trials measuring ADL compared an intervention with no treatment or with a control intervention.  Visual perception disorders: no trials measuring ADL compared an intervention with no treatment or control.  In addition, six trials reported ADL outcomes in a comparison of active intervention versus active intervention, relating to somatosensation (three trials), touch (one trial) and vision (two trials).   AUTHORS' CONCLUSIONS: Following a detailed, systematic search, we identified limited RCT evidence of the effectiveness of interventions for perceptual disorders following stroke. There is insufficient evidence to support or refute the suggestion that perceptual interventions are effective. More high-quality trials of interventions for perceptual disorders in stroke are needed. They should recruit sufficient participant numbers, include a 'usual care' comparison, and measure longer-term functional outcomes, at time points beyond the initial intervention period. People with impaired perception following a stroke should continue to receive neurorehabilitation according to clinical guidelines.

Technology for maintaining oral care after stroke: considerations for patient-centered practice

PURPOSE

Activities of daily living including oral care may be challenging after stroke. Some stroke survivors are not able to complete oral care independently and need assistance from healthcare professionals and care partners. Poor oral hygiene may impact stroke recovery and rehabilitation possibly incurring issues such as aspiration pneumonia, malnutrition, and social isolation. The objective of this paper is to outline practical ways to apply oral care technology in daily use for stroke survivors.

MATERIALS AND METHODS

We reviewed the literature on i) stroke-related impairments impacting oral care, ii) oral hygiene dental devices, and iii) technology for oral care education.

RESULTS

Oral care activities involve integrated skills in the areas of motivation, energy, planning, body movement and sensation, and mental acuity and health. Post-stroke impairments such as fatigue, hemiparesis, and mental impairments may impact oral care activities. Technology may help survivors and caregivers overcome some barriers. Three types of technologies are available for facilitating post-stroke oral care: i) non-powered tools and adaptations; ii) powered oral care tools, and; iii) electronic aids to guide oral care activities. Particular choices should maximise patient safety and autonomy while ensuring accessibility and comfort during oral care tasks.

CONCLUSION

The available device and technologies may help substantially with the accommodations needed for post-stroke oral care, improving the oral health of stroke survivors. Good oral health confers benefit to overall health and well-being and could enhance recovery and rehabilitation outcomes. Nonetheless, more research is necessary to demonstrate the feasibility and effectiveness of technology in stroke contexts.IMPLICATIONS FOR REHABILITATIONOral care may be challenging after stroke due to patient fatigue, hemiparesis, cognitive impairments, and other impaired body functions.Poor oral hygiene may impact stroke recovery and rehabilitation due to risk of aspiration pneumonia, malnutrition, and social isolation.Powered oral care tools, non-powered tools, and adaptations to non-powered tools are some of the technology available to help overcome post-stroke barriers for oral care.Computer programs and online resources for education and guidance for oral care activities may help improve recommendation uptake and compliance.

Effects of Neck Taping in the Treatment of Hemispatial Neglect in Chronic Stroke Patients: A Pilot, Single Blind, Randomized Controlled Trial

Background and objectives: Hemispatial neglect is a common consequence of stroke, with an estimated incidence of 23%. Interventions for treating hemispatial neglect may be categorized as either top-down or bottom-up processing. The aim of top-down approaches is to train the person to voluntarily compensate for their neglect. Such approaches require awareness of the disorder and a high level of active participation by the patient. Differently, bottom-up approaches are based on manipulation of a patient’s sensory environment and so require less awareness of behavioral bias. In line with the latter, it is conceivable that elastic therapeutic taping applied to the left neck surface may provide bottom-up inputs that reduce hemispatial neglect symptoms. The aim of this study was to assess the effect of therapeutic neck taping on visuo-spatial abilities, neck motion, and kinesthetic sensibility in chronic stroke patients with hemispatial neglect. Materials and Methods: After randomization, 12 chronic stroke patients with hemispatial neglect received 30 consecutive days of real (treatment group) or sham (control group) neck taping. The outcomes were as follows: Stars Cancellation Test; neck active range of motion; Letter Cancellation Test; Comb and Razor Test; Cervical Joint Position Error Test evaluated before and after one month of taping. Results: Between-group comparison showed significant differences only for the Cervical Joint Position Error Test after treatment (p = 0.009). Conclusions: Our preliminary findings support the hypothesis that neck taping might improve cervicocephalic kinesthetic sensibility in chronic stroke patients with hemispatial neglect. Further studies are needed to strengthen our results and better investigate the effects of elastic therapeutic taping on visuo-spatial abilities in stroke patients with hemispatial neglect.

Post-stroke visual neglect affects goal-directed locomotion in different perceptuo-cognitive conditions and on a wide visual spectrum

BACKGROUND

Unilateral spatial neglect (USN), a highly prevalent and disabling post-stroke deficit, has been shown to affect the recovery of locomotion. However, our current understanding of USN role in goal-directed locomotion control, and this, in different cognitive/perceptual conditions tapping into daily life demands, is limited.

OBJECTIVES

To examine goal-directed locomotion abilities in individuals with and without post-stroke USN vs. healthy controls.

METHODS

Participants (n = 45, n = 15 per group) performed goal-directed locomotion trials to actual, remembered and shifting targets located 7 m away at 0° and 15° right/left while immersed in a 3-D virtual environment.

RESULTS

Greater end-point mediolateral displacement and heading errors (end-point accuracy measures) were found for the actual and the remembered left and right targets among those with post-stroke USN compared to the two other groups (p <  0.05). A delayed onset of reorientation to the left and right shifting targets was also observed in USN+ participants vs. the other two groups (p <  0.05). Results on clinical near space USN assessment and walking speed explained only a third of the variance in goal-directed walking performance.

CONCLUSION

Post-stroke USN was found to affect goal-directed locomotion in different perceptuo-cognitive conditions, both to contralesional and ipsilesional targets, demonstrating the presence of lateralized and non-lateralized deficits. Beyond neglect severity and walking capacity, other factors related to attention, executive functioning and higher-order visual perceptual abilities (e.g. optic flow perception) may account for the goal-directed walking deficits observed in post-stroke USN+. Goal-directed locomotion can be explored in the design of future VR-based evaluation and training tools for USN to improve the currently used conventional methods.

Visual perceptual deficits and their contribution to walking dysfunction in individuals with post-stroke visual neglect

BACKGROUND

Unilateral spatial neglect (USN), a highly prevalent and disabling post-stroke deficit, severely affects functional mobility. Visual perceptual abilities (VPAs) are essential in activities involving mobility. However, whether and to what extent post-stroke USN affects VPAs and how they contribute to mobility impairments remains unclear.

OBJECTIVES

To estimate the extent to which VPAs in left and right visual hemispaces are (1) affected in post-stroke USN; and (2) contribute to goal-directed locomotion.

METHODS

Individuals with (USN+, n = 15) and without (USN-, n = 15) post-stroke USN and healthy controls (HC, n = 15) completed (1) psychophysical evaluation of contrast sensitivity, optic flow direction and coherence, and shape discrimination; and (2) goal-directed locomotion tasks.

RESULTS

Higher discrimination thresholds were found for all VPAs in the USN+ group compared to USN- and HC groups (p < 0.05). Psychophysical tests showed high sensitivity in detecting deficits in individuals with a history of USN or with no USN on traditional assessments, and were found to be significantly correlated with goal-directed locomotor impairments.

CONCLUSION

Deficits in VPAs may account for the functional difficulties experienced by individuals with post-stroke USN. Psychophysical tests used in the present study offer important advantages and can be implemented to enhance USN diagnostics and rehabilitation.

Ecological Virtual Reality Evaluation of Neglect Symptoms (EVENS): Effects of Virtual Scene Complexity in the Assessment of Poststroke Unilateral Spatial Neglect

Background. Unilateral spatial neglect (USN) is a highly prevalent and disabling poststroke impairment. USN is traditionally assessed with paper-and-pencil tests that lack ecological validity, generalization to real-life situations and are easily compensated for in chronic stages. Virtual reality (VR) can, however, counteract these limitations. Objective. We aimed to examine the feasibility of a novel assessment of USN symptoms in a functional shopping activity, the Ecological VR-based Evaluation of Neglect Symptoms (EVENS). Methods. EVENS is immersive and consists of simple and complex 3-dimensional scenes depicting grocery shopping shelves, where joystick-based object detection and navigation tasks are performed while seated. Effects of virtual scene complexity on navigational and detection abilities in patients with (USN+, n = 12) and without (USN−, n = 15) USN following a right hemisphere stroke and in age-matched healthy controls (HC, n = 9) were determined. Results. Longer detection times, larger mediolateral deviations from ideal paths and longer navigation times were found in USN+ versus USN− and HC groups, particularly in the complex scene. EVENS detected lateralized and nonlateralized USN-related deficits, performance alterations that were dependent or independent of USN severity, and performance alterations in 3 USN− subjects versus HC. Conclusion. EVENS’ environmental changing complexity, along with the functional tasks of far space detection and navigation can potentially be clinically relevant and warrant further empirical investigation. Findings are discussed in terms of attentional models, lateralized versus nonlateralized deficits in USN, and tasks-specific mechanisms.

Exploring barriers and facilitators to the clinical use of virtual reality for post-stroke unilateral spatial neglect assessment

BACKGROUND

Hemineglect, defined as a failure to attend to the contralesional side of space, is a prevalent and disabling post-stroke deficit. Conventional hemineglect assessments lack sensitivity as they contain mainly non-functional tasks performed in near-extrapersonal space, using static, two-dimensional methods. This is of concern given that hemineglect is a strong predictor for functional deterioration, limited post-stroke recovery, and difficulty in community reintegration. With the emerging field of virtual reality, several virtual tools have been proposed and have reported better sensitivity in neglect-related deficits detection than conventional methods. However, these and future virtual reality-based tools are yet to be implemented in clinical practice.

OBJECTIVES

The present study aimed to explore the barriers/facilitators perceived by clinicians in the use of virtual reality for hemineglect assessment; and to identify features of an optimal virtual assessment.

METHODS

A qualitative descriptive process, in the form of focus groups, self-administered questionnaire and individual interviews was used.

RESULTS

Two focus groups (n = 11 clinicians) were conducted and experts in the field (n = 3) were individually interviewed. Several barriers and facilitators, including personal, institutional, client suitability, and equipment factors, were identified. Clinicians and experts in the field reported numerous features for the virtual tool optimization.

CONCLUSION

Factors identified through this study lay the foundation for the development of a knowledge translation initiative towards an implementation of a virtual assessment for hemineglect. Addressing the identified barriers/facilitators during implementation and incorporating the optimal features in the design of the virtual assessment could assist and promote its eventual adoption in clinical settings. Implications for rehabilitation A multimodal and active knowledge translation intervention built on the presently identified modifiable factors is suggested to be implemented to support the clinical integration of a virtual reality-based assessment for post-stroke hemineglect. To amplify application and usefulness of a virtual-reality based tool in the assessment of post-stroke hemineglect, optimal features identified in the present study should be incorporated in the design of such technology.

Rehabilitation of unilateral neglect: Evidence-based medicine

BACKGROUND

In the last decades, several rehabilitation methods have been developed to improve spatial neglect. These can be classified according to their theoretical basis: (i) enhance awareness of neglect behaviour through a top-down mechanism; (ii) low-level bottom-up sensory stimulation; (iii) modulation of inhibitory processes; (iv) increase arousal.

OBJECTIVE

The purpose of this study was to provide an overview of the evidence on the effectiveness of rehabilitation procedures for unilateral neglect.

METHOD

A systematic search was performed to look for all randomised controlled trials aimed at reducing left spatial neglect that included a functional assessment. In addition, recent review papers and meta-analyses were analysed.

RESULTS

Thirty-seven randomized controlled trials were found (12 bottom-up; 12 top-down; 1 interhemispheric competition; 12 combination of approaches) that included 1027 patients with neglect. Although there are some encouraging results, overall, the level of evidence remains low. Poor methodological quality and small sample sizes are major limitations in many published trials.

CONCLUSION

There is a need for well-conducted, large-scale randomised controlled trials that incorporate blinded assessments, evaluation of the generalization to activities of daily living and long-term follow-up.

Examining the relationship between fatigue and cognition after stroke: A systematic review

Many stroke survivors experience fatigue, which is associated with a variety of factors including cognitive impairment. A few studies have examined the relationship between fatigue and cognition and have obtained conflicting results. The aim of the current study was to review the literature on the relationship between fatigue and cognition post-stroke. The following databases were searched: EMBASE (1980-February, 2014), PsycInfo (1806-February, 2014), CINAHL (1937-February, 2014), MEDLINE (1946-February, 2014), Ethos (1600-February, 2014) and DART (1999-February, 2014). Reference lists of relevant papers were screened and the citation indices of the included papers were searched using Web of Science. Studies were considered if they were on adult stroke patients and assessed the following: fatigue with quantitative measurements (≥ 3 response categories), cognition using objective measurements, and the relationship between fatigue and cognition. Overall, 413 papers were identified, of which 11 were included. Four studies found significant correlations between fatigue and memory, attention, speed of information processing and reading speed (r = -.36 to .46) whereas seven studies did not. Most studies had limitations; quality scores ranged from 9 to 14 on the Critical Appraisal Skills Programme Checklists. There was insufficient evidence to support or refute a relationship between fatigue and cognition post-stroke. More robust studies are needed.

Virtual reality treatment and assessments for post-stroke unilateral spatial neglect: A systematic literature review

Unilateral spatial neglect (USN) is a highly prevalent post-stroke deficit. Currently, there is no gold standard USN assessment which encompasses the heterogeneity of this disorder and that is sensitive to detect mild deficits. Similarly, there is a limited number of high quality studies suggesting that conventional USN treatments are effective in improving functional outcomes and reducing disability. Virtual reality (VR) provides enhanced methods for USN assessment and treatment. To establish best-practice recommendations with respect to its use, it is necessary to appraise the existing evidence. This systematic review aimed to identify and appraise existing VR-based USN assessments; and to determine whether VR is more effective than conventional therapy. Assessment tools were critically appraised using standard criteria. The methodological quality of the treatment trials was rated by two authors. The level of evidence according to stage of recovery was determined. Findings were compiled into a VR-based USN Assessment and Treatment Toolkit (VR-ATT). Twenty-three studies were identified. The proposed VR tools augmented the conventional assessment strategies. However, most studies lacked analysis of psychometric properties. There is limited evidence that VR is more effective than conventional therapy in improving USN symptoms in patients with stroke. It was concluded that VR-ATT could facilitate identification and decision-making as to the appropriateness of VR-based USN assessments and treatments across the continuum of stroke care, but more evidence is required on treatment effectiveness.

Effect of eye patching in rehabilitation of hemispatial neglect

Eye patching (EP; monocular or right hemifield) has been proposed to improve visuospatial attention to the ignored field in patients with hemispatial neglect. The aim of this paper is to review the literature on the effects of EP in hemispatial neglect after stroke in order to convey evidence-based recommendations to clinicians in stroke rehabilitation. Thirteen intervention studies were selected from the Medline, EMBASE, Scopus, Cochrane Library, CINAHL, PsychINFO, EBRSR, and Health Star databases. Methodological quality was defined according to the Physiotherapy Evidence Database. Overall, seven studies used monocular EP, five used right hemifield patching, and one compared right monocular with right hemifield patching. Seven studies compared normal viewing to monocular or hemifield patching conditions. Six studies included a period of treatment. As to the monocular EP, four studies reported positive effects of right monocular patching. One study showed an improvement in hemispatial neglect with left monocular patching. Two studies found no superiority of right vs. left monocular patching. One study found no effects of right monocular patching. As to the right hemifield EP, one study showed improvements in neglect after right hemifield patching. Three studies found that right hemifield patching combined with another rehabilitation technique was more effective than that treatment alone. One study found no differences between right hemifield patching combined with another treatment and that treatment alone. One study found the same effect between right hemifield patching alone and another rehabilitation technique. Our results globally tend to support the usefulness of right hemifield EP in clinical practice. In order to define a level of evidence with the standard rehabilitation evidence rating tools, further properly powered randomized controlled trials or meta-analysis are needed.

Cognitive rehabilitation for spatial neglect following stroke

BACKGROUND

Unilateral spatial neglect causes difficulty attending to one side of space. Various rehabilitation interventions have been used but evidence of their benefit is lacking.

OBJECTIVES

To assess whether cognitive rehabilitation improves functional independence, neglect (as measured using standardised assessments), destination on discharge, falls, balance, depression/anxiety and quality of life in stroke patients with neglect measured immediately post-intervention and at longer-term follow-up; and to determine which types of interventions are effective and whether cognitive rehabilitation is more effective than standard care or an attention control.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched June 2012), MEDLINE (1966 to June 2011), EMBASE (1980 to June 2011), CINAHL (1983 to June 2011), PsycINFO (1974 to June 2011), UK National Research Register (June 2011). We handsearched relevant journals (up to 1998), screened reference lists, and tracked citations using SCISEARCH.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of cognitive rehabilitation specifically aimed at spatial neglect. We excluded studies of general stroke rehabilitation and studies with mixed participant groups, unless more than 75% of their sample were stroke patients or separate stroke data were available.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, extracted data, and assessed study quality. For subgroup analyses, review authors independently categorised the approach underlying the cognitive intervention as either 'top-down' (interventions that encourage awareness of the disability and potential compensatory strategies) or 'bottom-up' (interventions directed at the impairment but not requiring awareness or behavioural change, e.g. wearing prisms or patches).

MAIN RESULTS

We included 23 RCTs with 628 participants (adding 11 new RCTs involving 322 new participants for this update). Only 11 studies were assessed to have adequate allocation concealment, and only four studies to have a low risk of bias in all categories assessed. Most studies measured outcomes using standardised neglect assessments: 15 studies measured effect on activities of daily living (ADL) immediately after the end of the intervention period, but only six reported persisting effects on ADL. One study (30 participants) reported discharge destination and one study (eight participants) reported the number of falls.Eighteen of the 23 included RCTs compared cognitive rehabilitation with any control intervention (placebo, attention or no treatment). Meta-analyses demonstrated no statistically significant effect of cognitive rehabilitation, compared with control, for persisting effects on either ADL (five studies, 143 participants) or standardised neglect assessments (eight studies, 172 participants), or for immediate effects on ADL (10 studies, 343 participants). In contrast, we found a statistically significant effect in favour of cognitive rehabilitation compared with control, for immediate effects on standardised neglect assessments (16 studies, 437 participants, standardised mean difference (SMD) 0.35, 95% confidence interval (CI) 0.09 to 0.62). However, sensitivity analyses including only studies of high methodological quality removed evidence of a significant effect of cognitive rehabilitation.Additionally, five of the 23 included RCTs compared one cognitive rehabilitation intervention with another. These included three studies comparing a visual scanning intervention with another cognitive rehabilitation intervention, and two studies (three comparison groups) comparing a visual scanning intervention plus another cognitive rehabilitation intervention with a visual scanning intervention alone. Only two small studies reported a measure of functional disability and there was considerable heterogeneity within these subgroups (I² > 40%) when we pooled standardised neglect assessment data, limiting the ability to draw generalised conclusions.Subgroup analyses exploring the effect of having an attention control demonstrated some evidence of a statistically significant difference between those comparing rehabilitation with attention control and those with another control or no treatment group, for immediate effects on standardised neglect assessments (test for subgroup differences, P = 0.04).

AUTHORS' CONCLUSIONS

The effectiveness of cognitive rehabilitation interventions for reducing the disabling effects of neglect and increasing independence remains unproven. As a consequence, no rehabilitation approach can be supported or refuted based on current evidence from RCTs. However, there is some very limited evidence that cognitive rehabilitation may have an immediate beneficial effect on tests of neglect. This emerging evidence justifies further clinical trials of cognitive rehabilitation for neglect. However, future studies need to have appropriate high quality methodological design and reporting, to examine persisting effects of treatment and to include an attention control comparator.

Rehabilitation of spatial neglect

Spatial neglect is a frequent cause of disability associated with high costs and duration of hospital stay, increased family burden, and requirements for skilled chronic care. This condition is disproportionately more frequent with right than left hemispheric injury and it is characterized by perceptual, representational, and behavioral deficits involving or directed towards the left hemispace or the left hemibody. Spatial dysfunction is conceptualized into two major components: the perceptual/representational "where" component that results mainly from injury to posterior brain regions and the premotor/intentional "aiming" component that results mostly from damage to anterior brain regions. Additionally, deficits in arousal, vigilance, affective symptoms, and disorders of emotional communication may compound the clinical manifestations of spatial neglect. Evidence-based sources that evaluate the effectiveness of rehabilitation treatments for neglect are, unfortunately, unable to provide a unified consensus for the efficacy of a given treatment approach. The reasons for this failure are related to internal inconsistencies defining appropriate criteria for treatment success and lack of characterization of neglect mechanisms and considerations of patient characteristics related to treatment failure. In this chapter we advocate the use of visual scanning, limb activation therapy, and "general treatment" because we believe that they are appropriately supported by different sources and they may be useful for experimental trials and standardized clinical care. We advocate an integrative approach that takes advantage of the same rehabilitation strategy or task to treat different perceptual, representational, and premotor components of neglect. A variety of therapies that may be familiar to the rehabilitation team may be useful as long as they are applied in a systematized program and are based on good clinical judgment. Information regarding adjuvant pharmacological therapy is sparse but different agents with aminergic and cholinergic activity may be useful. Medication with sedative, antidopaminergic or anticholinergic properties may interfere with the rehabilitation process and should be avoided.

Hemispheric differences in VEPs to lateralised stimuli are a marker of recovery from neglect

Visual-evoked potentials (VEPs) were recorded in seventeen patients with unilateral lesions of the right hemisphere (RH) and visuospatial neglect. Hemispheric differences were detected for VEP components in the time window from 130 to 280 msec; this result replicates data from a previous study using a larger group of patients (Di Russo et al., 2008). Three patients were tested twice; their hemispheric differences, i.e., the differences in latency and amplitude of VEPs to ipsilesional and contralesional stimuli, were evaluated at the beginning and end of visuospatial rehabilitation training for neglect. The hemispheric differences were limited to components anterior N1 (N1a), posterior N1 (N1p) and P2 (not C1 and P1) and showed a significant decrease after training; amelioration at the behavioural level was also observed. Fourteen patients were tested only once, at different steps of their training. For the overall group, we determined the correlation between VEP hemispheric differences and the number of sessions attended by the patients at the time of VEP recording. The correlation was negative, the higher the number of sessions, the lower the hemispheric asymmetry, and high, ranging from .45 to .64, for both the latency and amplitude of the N1p and P2 components, and for the amplitude of the N1a component. The correlation between VEP hemispheric differences and time from onset (TFO) of the pathological event was not significant. Overall, the hemispheric differences between specific components of the VEP responses to lateralised stimuli appear to be a good marker of recovery from neglect.

Superior colliculi involvement in poststroke unilateral spatial neglect: a pilot study

PURPOSE

The neural mechanisms underlying unilateral spatial neglect (USN) are unclear. The superior colliculi (SC) may be involved in USN expression, and the spatial summation effect (SSE), where reaction times to bilateral stimuli are faster than to unilateral, may be a behavioral index of SC function. We determined the feasibility of investigating SC contribution to poststroke USN using the SSE in 3 groups.

METHODS

Seven participants with left near-extrapersonal space USN (USN+) following right hemisphere stroke, 10 without (USN-), and 10 controls were tested under binocular/monocular (right eye patched) conditions while responding to unilateral/bilateral stimuli. Control and USN- groups completed the SSE paradigm.

RESULTS

Most USN+ participants were unable to initiate the SSE paradigm due to poor visual fi xation and demonstrated higher contrast sensitivity for left-sided stimuli. Controls showed an SSE (under both viewing conditions) while the USN- showed an abnormal SSE whereby reaction times to bilateral stimuli were faster than to unilateral-left but not to unilateral-right stimuli (under both binocular/monocular conditions).

CONCLUSION

This study is the fi rst to investigate SC contribution in poststroke USN using the SSE; we identifi ed higher contrast sensitivity to left-sided stimuli and poor fi xation in the USN+ group. These fi ndings suggest avenues for research that may lead to novel rehabilitation interventions.

Rehabilitation--emerging technologies, innovative therapies, and future objectives

Stroke is the leading cause of long-term disability. The goal of stroke rehabilitation is to improve recovery in the years after a stroke and to decrease long-term disability. This article, titled "Rehabilitation--Emerging Technologies, Innovative Therapies, and Future Objectives" gives evidence-based information on the type of rehabilitation approaches that are effective to improve functional mobility and to address cognitive impairments. We review the importance of taking a translational approach to neurorehabilitation, considering the interaction of motor and cognitive systems, skilled learned purposeful limb movement, and spatial navigation ability. Known biologic mechanisms of neurorecovery are targeted in relation to technology implemented by members of the multidisciplinary team. Results from proof-of-concept, within subjects, and randomized controlled trials are presented, and the implications for optimal stroke rehabilitation strategies are discussed. Developing clinical practices are highlighted and future research directions are proposed with goals to provide insight on what the next steps are for this burgeoning discipline.

Visual neglect following stroke: current concepts and future focus

Visual neglect is a common, yet frequently overlooked, neurological disorder following stroke characterized by a deficit in attention and appreciation of stimuli on the contralesional side of the body. It has a profound functional impact on affected individuals. A assessment and management of this condition are hindered, however, by the lack of professional awareness and clinical guidelines. Recent evidence suggests that the underlying deficit in visual attention is due to a disrupted internalized representation of the outer world rather than a disorder of sensory inputs. Dysfunction of the cortical domains and white-matter tracts, as well as inter-hemispheric imbalance, have been implicated in the various manifestations of visual neglect. Optimal diagnosis requires careful history-taking from the patient, family, and friends, in addition to clinical assessment with the line bisection test, the star cancellation test, and the Catherine Bergego Scale. Early recognition and prompt rehabilitation employing a multidisciplinary approach is desirable. Although no treatment has been definitively shown to be of benefit, those with promise include prism adaptation, visual scanning therapy, and virtual reality-based techniques. Further high quality research to seek optimum short- and long-term rehabilitative strategies for visual neglect is required.

Non-pharmacological interventions for perceptual disorders following stroke and other adult-acquired, non-progressive brain injury

BACKGROUND

Stroke and other adult-acquired brain injury may impair perception leading to distress and increased dependence on others. Perceptual rehabilitation includes functional training, sensory stimulation, strategy training and task repetition.

OBJECTIVES

To examine the evidence for improvement in activities of daily living (ADL) six months post randomisation for active intervention versus placebo or no treatment.

SEARCH STRATEGY

We searched the trials registers of the Cochrane Stroke Group and the Cochrane Infectious Diseases Group (May 2009) but not the Injuries Group, the Cochrane Central Register of Controlled Trials (The Cochrane Library 2009, Issue 3), MEDLINE (1950 to August 2009), EMBASE (1980 to August 2009), CINAHL (1982 to August 2009), PsycINFO (1974 to August 2009), REHABDATA and PsycBITE (May to June 2009). We also searched trials and research registers, handsearched journals, searched reference lists and contacted authors.

SELECTION CRITERIA

Randomised controlled trials of adult stroke or acquired brain injury. Our definition of perception excluded visual field deficits, neglect/inattention and apraxia.

DATA COLLECTION AND ANALYSIS

One review author assessed titles, abstracts and keywords for eligibility. At least two review authors independently extracted data. We requested unclear or missing information from corresponding authors.

MAIN RESULTS

We included six single-site trials in rehabilitation settings, involving 338 participants. Four trials included people with only stroke. All studies provided sensory stimulation, sometimes with another intervention. Sensory stimulation typically involved practising tasks that required visuo-perceptual processing with occupational therapist assistance. Repetition was never used and only one study included functional training. No trials provided data on longer term improvement in ADL scores. Only three trials provided any data suitable for analysis. Two of these trials compared active to placebo intervention. There was no evidence of a difference in ADL scores at the scheduled end of intervention: mean difference (95% confidence interval (CI)) was 0.9 (-1.6 to 3.5) points on a self-care ADL scale in one study and odds ratio (95% CI) was 1.3 (0.56 to 3.1) for passing a driving test in the other, both in favour of active intervention. The trial that compared two active interventions did not find evidence of difference in any of the review outcomes.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the view that perceptual interventions are effective. Future studies should be sufficiently large, include a standard care comparison and measure longer term functional outcomes. People with impaired perception problems should continue to receive neurorehabilitation according to clinical guidelines.

Contribution of the superior colliculi to post-stroke unilateral spatial neglect and recovery

Unilateral spatial neglect (USN) is a highly prevalent and disabling consequence of stroke that often responds poorly to existing interventions. Its underlying neural mechanisms are still unclear. Recent work suggests that post-stroke USN may be partly related to a disruption of top-down and bottom-up control of visual attention mediated in part through the midbrain superior colliculi (SC). With mounting evidence from animal and human research, our objectives were: (1) to synthesize the literature implicating the SC in USN; (2) to review the rationale and potential for using eye patching and prism adaptation as USN treatment approaches that recruit SC involvement; and (3) to provide recommendations for research on the potential of therapeutic interventions that involve and/or target the retino-collicular pathway. Given the paucity of human studies, the contribution of the SC in USN, while plausible, remains to be confirmed. Further exploration of the mechanisms involved and their impact on USN in human subjects will help develop theoretically based intervention strategies tailored to USN type.

The number of patients with communication related impairments in acute hospital stroke units

Effective communication between patients who have had a stroke and their healthcare providers is vital. However, this may be difficult if patients have communication related impairments as a result of the stroke and/or have age related impairments that impact on their ability to communicate. This study sought to identify how many patients admitted into two acute hospital stroke units had a hearing, vision, speech, language and/or cognitive communicative impairment regardless of the cause. A total of 69 patients participated in this study. The majority (88%) of patients had one or more mild or more severe communication related impairments, 69% of patients had two or more communication related impairments and 39% of patients had three or more communication related impairments. The most common type of impairment was hearing impairment, followed by near vision impairment. That a high number of patients in acute hospital stroke units have communication related impairments suggests that many patients in acute stroke units may experience difficulty communicating their healthcare needs with healthcare providers and that alternative ways to support patients with communication related impairments in acute stroke units need to be available.

Evidence-based cognitive rehabilitation: updated review of the literature from 1998 through 2002

OBJECTIVE

To update the previous evidence-based recommendations of the Brain Injury Interdisciplinary Special Interest Group of the American Congress of Rehabilitation Medicine for cognitive rehabilitation of people with traumatic brain injury (TBI) and stroke, based on a systematic review of the literature from 1998 through 2002.

DATA SOURCES

PubMed and Infotrieve literature searches were conducted using the terms attention, awareness, cognition, communication, executive, language, memory, perception, problem solving, and reasoning combined with each of the terms rehabilitation, remediation, and training. Reference lists from identified articles were reviewed and a bibliography listing 312 articles was compiled.

STUDY SELECTION

One hundred eighteen articles were initially selected for inclusion. Thirty-one studies were excluded after detailed review. Excluded articles included 14 studies without data, 6 duplicate publications or follow-up studies, 5 nontreatment studies, 4 reviews, and 2 case studies involving diagnoses other than TBI or stroke.

DATA EXTRACTION

Articles were assigned to 1 of 7 categories reflecting the primary area of intervention: attention; visual perception; apraxia; language and communication; memory; executive functioning, problem solving and awareness; and comprehensive-holistic cognitive rehabilitation. Articles were abstracted and levels of evidence determined using specific criteria.

DATA SYNTHESIS

Of the 87 studies evaluated, 17 were rated as class I, 8 as class II, and 62 as class III. Evidence within each area of intervention was synthesized and recommendations for practice standards, practice guidelines, and practice options were made.

CONCLUSIONS

There is substantial evidence to support cognitive-linguistic therapies for people with language deficits after left hemisphere stroke. New evidence supports training for apraxia after left hemisphere stroke. The evidence supports visuospatial rehabilitation for deficits associated with visual neglect after right hemisphere stroke. There is substantial evidence to support cognitive rehabilitation for people with TBI, including strategy training for mild memory impairment, strategy training for postacute attention deficits, and interventions for functional communication deficits. The overall analysis of 47 treatment comparisons, based on class I studies included in the current and previous review, reveals a differential benefit in favor of cognitive rehabilitation in 37 of 47 (78.7%) comparisons, with no comparison demonstrating a benefit in favor of the alternative treatment condition. Future research should move beyond the simple question of whether cognitive rehabilitation is effective, and examine the therapy factors and patient characteristics that optimize the clinical outcomes of cognitive rehabilitation.