View clinical trials related to Hemianopsia.
Filter by:Brain malignancies are the most common cause of death from cancer in the pediatric population and a major source of morbidity amongst survivors. Many children with a brain tumour often suffer from visual field defects (hemianopia) dramatically impacting their daily life with poorer social interaction, difficulties learning, playing sports and engaging with peers. Practically, they bump into people and objects and have problems in finding their way in unfamiliar places and in detecting incoming objects in their blind field. There is growing recognition of the diverse and deep impact of hemianopia on physical and mental health, quality of life, and social outcomes of the affected individuals and their family. However, despite the frequent impact of brain tumours on the visual function and functional vision, ophthalmologic evaluations are not standard of care for all brain tumour patients and there are no standardized protocols of vision loss management in the pediatric population with hemianopia. There is an unmet need of restoring perception in the blind field in individuals with hemianopia consecutive to pediatric brain tumor. Our laboratory has developed a visual rehabilitation procedure based on the combination of adaptative audio and visual target tracking in a 3D environment in virtual reality. Participants perform audiovisual stimulation at home in a headset, with remote control from the laboratory. Preliminary on data on paediatric patients with hemianopia consecutive to a brain tumour indicate feasibility and potential effectiveness of a 6-week Re:Vision program on visual fields, visual perception and quality of life. Our objective is to evaluate the effectiveness of Re:Vision, an 8-week visual telerehabilitation program, on visual perception in 50 individuals aged 10-40 years old with hemianopia consecutive to a pediatric brain tumor in a phase IIa/b multi-centric clinical study across Canada. This intervention provides more equitable access to individuals, with the ability to receive rehabilitation therapy at home without supervision by a healthcare professional, meaning that Canadians living outside urban centres could take advantage of specialized therapies with remote supervision. This is the first study that could lead to a major change in the management of these patients. It could open the door for visual rehabilitation strategies to other population of visually impaired children, significantly impacting public health strategies.
The purpose of this study is to investigate how visual orientation discrimination and metacognition (i.e., perceptual confidence) are affected by occipital stroke that causes hemianopia and quadrantanopia in adults. This research will provide insight as to how the residual visual system, which not directly damaged by the occipital stroke, processes orientation (assayed in terms of orientation discrimination) and metacognition (by measuring perceptual confidence for orientation discrimination). These measures will be used to refine computational models that attempt to explain how the brain copes with loss of primary visual cortex (V1) as a result of stroke. This knowledge is essential to devise more effective visual rehabilitation therapies for patients suffering from occipital strokes.
Brain injuries may cause the loss of the ability to see portions of the visual field, the so-called visual field defects (VFDs). VFDs significantly impact the survivors' functional recovery and quality of life, with the majority of patients displaying no spontaneous recovery or being left with residual deficits. Among the available therapies for VFDs, the compensatory scanning training is considered the most promising. Yet, current evidence is insufficient to recommend it in clinical practice, and the scientific community has stressed the need of more high-quality research. The present randomized clinical trial in patients with chronic VFDs caused by brain lesions aims at verifying the feasibility and efficacy of a novel telerehabilitation using a multisensory scanning therapy, by measuring its effects on visual functions and daily activities, and by looking for neural indicators of the therapy-induced improvements.
The purpose of this study is to assess wether the SONDA visual field test is suitable for patients with a supra sellar tumour.
In patients with hemianopsia following stroke or brain injury, we will determine if stimulating the visual field with images from a PowerPoint slide set can increase the visual field.
This study will evaluate a new approach to training people with visual field loss to scan when driving
This project is intended to collect data using standard clinical tests and psychophysics to quantify the effect of visual cortical damage on the structure of the residual visual system, visual perception, spatial awareness, and brain function. The investigators will also assess the effect of intensive visual retraining on the residual visual system, processing of visual information and the use of such information in real-world situations following damage. This research is intended to improve our understanding of the consequences of permanent visual system damage in humans, of methods that can be used to reverse visual loss, and of brain mechanisms by which visual recovery is achieved.
Homonymous visual field defects (HVFDs) following acquired brain lesions affect independent living by hampering several activities of everyday life. Available treatments are intensive and week- or month-long. Transcranial Direct current stimulation (tDCS), a plasticity-modulating non-invasive technique, could be combined with behavioral trainings to boost their efficacy or reduce treatment duration. Some promising attempts have been made pairing occipital tDCS with visual restitution training, however less is knows about which area/network should be best stimulated in association with compensatory approaches, aimed at improving exploratory abilities, such as multisensory trainings. In the present double-blind, sham-controlled study, we assess the efficacy of a multisensory training combined with tDCS. 3 groups of participants with chronic HVFDs underwent a 10-day (1.5 hrs/day) compensatory audio-visual training combined with either real anodal tDCS applied to the ipsilesional occipital tDCS (Group 1), or the ipsilesional posterior parietal cortex (Group 2), or a sham, placebo, tDCS (Group 3). The training require the participants to orient their gaze training spatio-temporally congruent, cross-modal, audio-visual stimuli (starting from a central fixation) and press a button as quick as possible upon the detection of the visual stimulus. All stimuli are presented on 2mx2m panel embedded with 48 LEDs and loudspeakers (Bolognini et al., 2010, Brain Research) All participants underwent a neuropsychological assessment of visuospatial functions prior to the beginning of the training (t0), at the end of the training (t1), and at 1-month (t2) and 4-month follow-up (t3). The assessment includes: a visual detection task, three visual search tasks (EF, Triangles, and Numbers; Bolognini et al., 2005, Brain), and a questionnaire about functional impact of the HVFDs in the activities of daily living.
The study will consist of two connected components at a single centre. Phase 1 is observational, phenotyping children with Homonymous hemianopia (HH). Phase 2 is a pilot double blind cross over RCT in which segmental prisms are compared with sham prisms in glasses.
The purpose of this research is to better understand the impact of cortically-induced blindness (CB) and the compensatory strategies subjects with this condition may develop on naturalistic behaviors, specifically, driving. Using a novel Virtual Reality (VR) program, the researchers will gather data on steering behavior in a variety of simulated naturalistic environments. Through the combined use of computer vision, deep learning, and gaze-contingent manipulations of the visual field, this work will test the central hypothesis that changes to visually guided steering behaviors in CB are a consequence of changes to the visual sampling and processing of task-related motion information (i.e., optic flow).