Ameliorating Hemianopia with Multisensory Training.

Hemianopia (unilateral blindness), a common consequence of stroke and trauma to visual cortex, is a debilitating disorder for which there are few treatments. Research in an animal model has suggested that visual-auditory stimulation therapy, which exploits the multisensory architecture of the brain, may be effective in restoring visual sensitivity in hemianopia. It was tested in two male human patients who were hemianopic for at least 8 months following a stroke. The patients were repeatedly exposed to congruent visual-auditory stimuli within their blinded hemifield during 2 h sessions over several weeks. The results were dramatic. Both recovered the ability to detect and describe visual stimuli throughout their formerly blind field within a few weeks. They could also localize these stimuli, identify some of their features, and perceive multiple visual stimuli simultaneously in both fields. These results indicate that the multisensory therapy is a rapid and effective method for restoring visual function in hemianopia.SIGNIFICANCE STATEMENT Hemianopia (blindness on one side of space) is widely considered to be a permanent disorder. Here, we show that a simple multisensory training paradigm can ameliorate this disorder in human patients.

Non-invasive electrical brain stimulation for vision restoration after stroke: An exploratory randomized trial (REVIS).

BACKGROUND: Occipital strokes often cause permanent homonymous hemianopia leading to significant disability. In previous studies, non-invasive electrical brain stimulation (NIBS) has improved vision after optic nerve damage and in combination with training after stroke. OBJECTIVE: We explored different NIBS modalities for rehabilitation of hemianopia after chronic stroke. METHODS: In a randomized, double-blinded, sham-controlled, three-armed trial, altogether 56 patients with homonymous hemianopia were recruited. The three experiments were: i) repetitive transorbital alternating current stimulation (rtACS, n = 8) vs. rtACS with prior cathodal transcranial direct current stimulation over the intact visual cortex (tDCS/rtACS, n = 8) vs. sham (n = 8); ii) rtACS (n = 9) vs. sham (n = 9); and iii) tDCS of the visual cortex (n = 7) vs. sham (n = 7). Visual functions were evaluated before and after the intervention, and after eight weeks follow-up. The primary outcome was change in visual field assessed by high-resolution and standard perimetries. The individual modalities were compared within each experimental arm. RESULTS: Primary outcomes in Experiments 1 and 2 were negative. Only significant between-group change was observed in Experiment 3, where tDCS increased visual field of the contralesional eye compared to sham. tDCS/rtACS improved dynamic vision, reading, and visual field of the contralesional eye, but was not superior to other groups. rtACS alone increased foveal sensitivity, but was otherwise ineffective. All trial-related procedures were tolerated well. CONCLUSIONS: This exploratory trial showed safety but no main effect of NIBS on vision restoration after stroke. However, tDCS and combined tDCS/rtACS induced improvements in visually guided performance that need to be confirmed in larger-sample trials.NCT01418820 (clinicaltrials.gov).

2017 Charles F. Prentice Award Lecture: Peripheral Prisms for Visual Field Expansion: A Translational Journey.

On the occasion of being awarded the Prentice Medal, I was asked to summarize my translational journey. Here I describe the process of becoming a low-vision rehabilitation clinician and researcher, frustrated by the unavailability of effective treatments for some conditions. This led to decades of working to understand patients' needs and the complexities and subtleties of their visual systems and conditions. It was followed by many iterations of developing vision aids and the techniques needed to objectively evaluate their benefit. I specifically address one path: the invention and development of peripheral prisms to expand the visual fields of patients with homonymous hemianopia, leading to our latest multiperiscopic prism (mirror-based design) with its clear 45° field-of-view image shift.

Effects of visual search training in children with hemianopia.

BACKGROUND: This study investigates the effect of a new computer-based visual search training (VST) that was adapted for children with homonymous hemianopia (HH). METHODS: 22 children with HH (median age 11 years, 8 months: 6y6m-19y2m) trained at home for 15 minutes twice/day, 5 days/week, for 6 weeks. To assess performance before training (T1), directly after training (T2) and 6 weeks after the end of training (T3), we measured search times (STs) during on-screen search (with eye tracking), and in a real life search task. Additional variables analyzed during on-screen search were numbers, amplitudes, and durations of saccades, their directional patterns and the proportional number of saccades into the non-seeing field. The latter was the main variable during free viewing. Sixteen healthy age-matched children, who did not undergo the training, served as comparison group. Quality of Life (QoL)-questionnaires were also applied. RESULTS: STs of the patients decreased significantly during the training and all search performance tests. This improvement persisted 6 weeks after the end of the training. Saccade amplitudes increased, total number of saccades to find the target decreased, and the proportional number of saccades to the non-seeing side increased. These changes were maintained at T3. Saccade durations did not change. During free viewing, saccades were equally distributed to both sides before and after training. Patients reported improvements in QoL and activities of daily living. Performance in the healthy children did not change by simply repeating the visual search test. CONCLUSIONS: The improvement in STs in all search tasks, larger and fewer saccades, and an improved search strategy after VST suggests that the children with HH benefited from the training. The maintained improvement at T3 and the improvement in the real life search task indicate that the newly developed search strategy persists and can be applied to everyday life.

An atypical presentation of functional visual loss: A case report.

RATIONALE: Functional visual loss (FVL) can manifest as various symptoms. Decreased distant visual acuity is the most common symptom and visual field defect is the second most common symptom. Hemianopsia is rarely reported. In an atypical situation of FVL, it is important to prove that no organic pathology exists, through detailed history taking and appropriate examinations. PATIENT CONCERNS: This review presents the case of a 48-year-old male patient presented with decreased bilateral visual acuity and visual field defect after a traffic accident 3 weeks ago. Visual field test showed atypical features of FVL in which visual field change from binasal hemianopsia to left homonymous hemianopsia. DIAGNOSIS: The best corrected visual acuities (BCVA) were 20/63 in both eyes and binasal hemianopsia was observed on a Humphrey visual field test. Brain computed tomography (CT) scan and magnetic resonance imaging (MRI) showed no abnormalities in the brain and optic chiasm. Two weeks after presentation, however, the patient's visual field defect changed from binasal hemianopsia to left homonymous hemianopsia. We diagnosed it as FVL due to conversion disorder. INTERVENTION AND OUTCOMES: We decided to cooperate with a psychiatrist for cognitive behavioral therapy and the patient is under observation. LESSONS: Binasal hemianopsia and homonymous hemianopsia are rare; however, it may occur simultaneously in 1 patient with FVL. The possibility of FVL should be considered when there is atypical visual field defect and no organic abnormalities are observed. Repeated Humphrey field test and VEP may be helpful in diagnosis of FVL.

Restoration of Vision After Brain Injury Using Magnet Glasses.

Visual impairments are common after traumatic brain injury (TBI) and negatively affect quality of life. We describe a 39-year-old woman with a severe TBI who was evaluated by the inpatient optometry and vision rehabilitation service with findings of complete right homonymous hemianopia and right cranial nerve III palsy with 30-degree right exotropia (eye turn out) and complete right ptosis (eyelid will not open). The 30-degree exotropia advantageously generated 30 degrees of right visual field expansion when the right ptosis was treated with a magnetic levator prosthesis, which restores eyelid opening. Once opened, the patient used visual field expansion derived from a right exotropia to overcome functional impairments caused by right hemianopia. Field expansion improved the patient's wheelchair mobility and reaching tasks during inpatient therapy. This is the first report of visual field expansion by strabismus facilitated by correction of ptosis. Strabismus should be considered for its potential field expansion benefits when homonymous visual deficits are present, before considering patching. A multidisciplinary vision rehabilitation team is well suited to make this determination.

Use of NeuroEyeCoach™ to Improve Eye Movement Efficacy in Patients with Homonymous Visual Field Loss.

Visual field deficits are common in patients with damaged retinogeniculostriate pathways. The patient's eye movements are often affected leading to inefficient visual search. Systematic eye movement training also called compensatory therapy is needed to allow patients to develop effective coping strategies. There is a lack of evidence-based, clinical gold-standard registered medical device accessible to patients at home or in clinical settings and NeuroEyeCoach (NEC) is developed to address this need. In three experiments, we report on performance of patients on NEC compared to the data obtained previously on the earlier versions of the search task (n = 32); we assessed whether the self-administered computerised tasks can be used to monitor the progress (n = 24) and compared the findings in a subgroup of patients to a healthy control group. Performance on cancellation tasks, simple visual search, and self-reported responses on activities of daily living was compared, before and after training. Patients performed similarly well on NEC as on previous versions of the therapy; the inbuilt functionality for pre- and postevaluation functions was sensitive to allowing assessment of improvements; and improvements in patients were significantly greater than those in a group of healthy adults. In conclusion, NeuroEyeCoach can be used as an effective rehabilitation tool to develop compensatory strategies in patients with visual field deficits after brain injury.

A User and Their Family's Perspective of The Use of a Low-Tech Vs A High-Tech AAC System.

This qualitative case study describes a 9-year-old child, diagnosed with homonymous hemianopia, left side weakness and seizures that has been followed by Access to Communication and Technology Unit in Malta for 5 years. The child previously used a communication book and now uses an iPad as a speech generating device. A semi-structured interview was utilised with the parent to explore preference for each AAC system and the reasons for it. The impact of each AAC system on the family and on the child's communication skills, and perceived barriers in the implementation of the AACs were also explored. The child's own experience using the AAC systems was also investigated using a structured interview format. Talking Mats was used to support the child's understanding of the questions and to explore her perspectives on the two AAC systems using Yes-No responses. The parent interview was analysed thematically and represented visually using a thematic network. This was compared with child responses. Four organising themes emerged including barriers, benefits, facilitators, and expectations. Specific barriers included self-funding in order to provide the child with the best fit high-tech AAC. Perceived benefits for both AAC systems were that it increased her communicative intent. The child's mother perceived access to increased vocabulary and capacity for sentence building, operational autonomy as well as voice output as a benefit of the SGD. The child's results indicated a preference for the high-tech AAC because she found it easier to navigate than the low-tech AAC.

A randomised controlled trial to compare the clinical and cost-effectiveness of prism glasses, visual search training and standard care in patients with hemianopia following stroke: a protocol.

INTRODUCTION: Homonymous hemianopia is a common and disabling visual problem after stroke. Currently, prism glasses and visual scanning training are proposed to improve it. The aim of this trial is to determine the effectiveness of these interventions compared to standard care. METHODS AND ANALYSIS: The trial will be a multicentre three arm individually randomised controlled trial with independent assessment at 6 week, 12 week and 26 week post-randomisation. Recruitment will occur in hospital, outpatient and primary care settings in UK hospital trusts. A total of 105 patients with homonymous hemianopia and without ocular motility impairment, visual inattention or pre-existent visual field impairment will be randomised to one of three balanced groups. Randomisation lists will be stratified by site and hemianopia level (partial or complete) and created using simple block randomisation by an independent statistician. Allocations will be disclosed to patients by the treating clinician, maintaining blinding for outcome assessment. The primary outcome will be change in visual field assessment from baseline to 26 weeks. Secondary measures will include the Rivermead Mobility Index, Visual Function Questionnaire 25/10, Nottingham Extended Activities of Daily Living, Euro Qual-5D and Short Form-12 questionnaires. Analysis will be by intention to treat. ETHICS AND DISSEMINATION: This study has been developed and supported by the UK Stroke Research Network Clinical Studies Group working with service users. Multicentre ethical approval was obtained through the North West 6 Research ethics committee (Reference 10/H1003/119). The trial is funded by the UK Stroke Association. Trial Registration: Current Controlled Trials ISRCTN05956042. Dissemination will consider usual scholarly options of conference presentation and journal publication in addition to patient and public dissemination with lay summaries and articles. TRIAL REGISTRATION: Current Controlled Trials ISRCTN05956042.

Use of yoked prisms in patients with acquired brain injury: a retrospective analysis.

PRIMARY OBJECTIVE: The purpose of this retrospective study was to determine the clinical practices for prescribing yoked prisms, as well as to assess related patient responses, in a sample of visually-symptomatic patients having acquired brain injury (ABI). METHODS: The clinical records of individuals with acquired brain injury (ABI) that were assessed for yoked prisms were reviewed retrospectively. This query resulted in 60 patient records for analysis between January 2011 and December 2012. The following diagnostic groups were analysed: homonymous hemianopsia (HH)/homonymous quadranopsia, abnormal egocentric localization (AEL) and visual neglect. RESULTS: HH/homonymous quadranopsia (58.3%) was the primary indication to prescribe yoked prisms, followed by visual neglect/unilateral spatial inattention (USI) (40.0%) and AEL (11.7%). The most common favourable patient responses were increased awareness of their blind visual field and improved gait, mobility and balance. The magnitude and direction of prisms prescribed were dependent upon the subjective responses in patients manifesting AEL. In contrast, base direction was dependent upon the direction of visual field loss in patients with HH/homonymous quadranopsia and visual neglect. CONCLUSIONS: Two-thirds of the present sample population responded favourably to the yoked prisms. The results of the present study should prove useful to clinicians for the successful prescription of yoked prisms as a treatment modality in patients presenting with the above three diagnoses.

Smooth Pursuit "Bedside" Training Reduces Disability and Unawareness During the Activities of Daily Living in Neglect: A Randomized Controlled Trial.

UNLABELLED: Background Neglect is associated with disability, unawareness, poor long-term outcome, and dependence from caregivers. No randomized trial has evaluated the effects of smooth pursuit eye movement training (SPT) and visual scanning training (VST) at the bedside on these variables. Objective To compare the effects of SPT and VST in postacute stroke at 1 month with left neglect. METHODS: We carried out an assessor-blinded, randomized controlled trial. The 24 participants were randomly allocated to either SPT or VST (n = 12 each). They received 20 treatment sessions lasting 30 minutes each at the bedside over 4 weeks. Outcome measures included the Functional Neglect Index (FNI) based on 4 tasks: find objects on a tray, stick bisection, picture search, and gaze orientation. In addition, the Unawareness and Behavioral Neglect Index (UBNI) with 6 items about unawareness and 4 about neglect in activities of daily living, the Help index (required assistance in 10 functional activities), the Barthel Index, and the rehabilitation phase were rated by treatment-blinded assessors. Outcome measures were obtained before and immediately after the end of the interventions and at a 2-week follow-up. Results Significantly greater improvements were obtained after SPT versus VST treatment in the FNI and UBNI, and there were continued improvements selectively in the SPT group 2 weeks later. Conclusions SPT accelerates recovery from functional neglect and reduces unawareness significantly. Bedside neglect treatment using SPT is effective and feasible early after stroke.

Passive auditory stimulation improves vision in hemianopia.

UNLABELLED: Techniques employed in rehabilitation of visual field disorders such as hemianopia are usually based on either visual or audio-visual stimulation and patients have to perform a training task. Here we present results from a completely different, novel approach that was based on passive unimodal auditory stimulation. Ten patients with either left or right-sided pure hemianopia (without neglect) received one hour of unilateral passive auditory stimulation on either their anopic or their intact side by application of repetitive trains of sound pulses emitted simultaneously via two loudspeakers. Immediately before and after passive auditory stimulation as well as after a period of recovery, patients completed a simple visual task requiring detection of light flashes presented along the horizontal plane in total darkness. The results showed that one-time passive auditory stimulation on the side of the blind, but not of the intact, hemifield of patients with hemianopia induced an improvement in visual detections by almost 100% within 30 min after passive auditory stimulation. This enhancement in performance was reversible and was reduced to baseline 1.5 h later. A non-significant trend of a shift of the visual field border toward the blind hemifield was obtained after passive auditory stimulation. These results are compatible with the view that passive auditory stimulation elicited some activation of the residual visual pathways, which are known to be multisensory and may also be sensitive to unimodal auditory stimuli as were used here. TRIAL REGISTRATION: DRKS00003577.

Homonymous hemianopsia.

Homonymous hemianopia (HH) is a visual field defect involving either two right or the two left halves of the visual field of both eye. It results from the damage of the visual pathway in its suprachiasmatic part. The causes of HH include stroke, brain tumors, head injuries, neurosurgical procedures, multiple sclerosis and miscellaneous conditions. HH result in a severe visual impairment and affect a variety of cognitive visual functions. Patients with HH frequently have difficulties with reading and scanning scenes in sufficiently rapid fashion to make sense of things as a whole. They stumble, fall or knock objects in their surroundings, since they cannot see them and they are frequent surprised that somebody or something suddenly appeared in their visual field. The prognosis of visual field deficit recovery is highly variable and depends on the cause and severity of brain nd optic pathway injury. The fundamental method in the management of HH patients is rehabilitation. Rehabilitation techniques used in HH include three groups of methods: optical therapies, eye movement-based therapies, and visual field restitution therapies.