10 Clinical Trials for Various Conditions
This research will explore if brain stimulation combined with virtual reality therapy improves visual impairment. The stimulation technique is called low-intensity focused ultrasound stimulation (LIFUS). The treatment uses ultrasound to stimulate vision specific parts of the brain. Before this therapy, the participants will get structural brain imaging. Functional brain imaging will be performed before and after the study's completion to measure brain activity response to therapy. The purpose of this research study is to evaluate patients who have had a stroke between 6 and 24 months ago with a visual field impairment. The duration of active participation in the study is 1.5 months.
This is a randomized, pilot interventional study in participants with visual field deficit (VFD) caused by cortical lesion. Damage to the primary visual cortex (V1) causes a contra-lesional, homonymous loss of conscious vision termed hemianopsia, the loss of one half of the visual field. The goal of this project is to elaborate and refine a rehabilitation protocol for VFD participants. It is hypothesized that visual restoration training using moving stimuli coupled with noninvasive current stimulation on the visual cortex will promote and speed up recovery of visual abilities within the blind field in VFD participants. Moreover, it is expected that visual recovery positively correlates with reduction of the blind field, as measured with traditional visual perimetry: the Humphrey visual field test or an eye-tracker based visual perimetry implemented in a virtual reality (VR) headset. Finally, although results will vary among participants depending on the extent and severity of the cortical lesion, it is expected that a bigger increase in neural response to moving stimuli in the blind visual field in cortical motion area, for those participants who will show the largest behavioral improvement after training. The overarching goals for the study are as follows: Group 1a will test the basic effects of transcranial random noise stimulation (tRNS) coupled with visual training in stroke cohorts, including (i) both chronic/subacute ischemic and chronic hemorrhagic VFD stroke participants, and (ii) longitudinal testing up to 6 months post-treatment. Group 1b will test the effects of transcranial tRNS coupled with visual training on a Virtual Reality (VR) device in stroke cohorts, including both chronic/subacute ischemic and chronic hemorrhagic VFD stroke participants. Group 2 will examine the effects of tRNS alone, without visual training, also including chronic and subacute VFD stroke participants and longitudinal testing.
This research aims to examine changes in plastic potential of the visual system with time from stroke affecting primary visual cortex. We will measure structural and mechanistic aspects of progressive degeneration along the early visual pathways, correlating them with changes in visual performance, and in responsiveness to visual restoration training. This project will advance both scientific knowledge, as well as technical capability and clinical practices for restoring vision and quality of life for people suffering from cortical blindness.
The investigators will develop and test different configurations of high-power prisms to expand the field of vision of patients with visual field loss to assist them with obstacle detection when walking. The study will involve multiple visits (typically four) to Schepens Eye Research Institute for fitting and testing with the prism glasses. The overall objective is to determine best designs and fitting parameters for implementation in prism devices for future clinical trials.
This study is designed in two Phases. In phase 1, the Functional Outcome Measure will be tested to determine its validity and reliability in three populations, subjects that have not had a stroke and have no visual field defect, subjects that have had a stroke but do not have a visual field defect, and lastly subjects that have had a stroke and have a visual field defect. The second phase will employ an amended version of the functional outcome measure to be administered to two groups of subjects. The first group of subjects will be those subjects diagnosed with a visual field defect from retrochiasmatic insults and they will perform vision restoration therapy. The second group with a similar diagnosis to the first but who do not undergo vision restoration therapy.
The investigators are developing a new test of pedestrian hazard detection in virtual reality (VR) head-mounted display (HMD) headset, which shows virtual oncoming pedestrians in 3D while subjects are walking in real-world environment, for evaluation of visual field expansion to improve mobility in people with visual field loss.
This project aims to develop a novel visual training paradigm for use in visually-intact participants and those sufferings from stroke-induced visual impairments. Our task design is built upon theories of statistical learning to reduce the overall training burden while still producing profound improvements to visual abilities. Efficacy will be first established in visually-intact controls before testing in stroke survivors to assess the feasibility of this form of learning in the damaged visual system.
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).
This study evaluates a novel collision warning device to help people with severe vision impairment or blindness avoid collisions with obstacles. The main hypothesis to be tested is that the device reduces the number of collisions with obstacles in everyday activities.
The Bioness Integrated Therapy System (BITS) (Bioness Inc. Valencia, CA) Touch Screen is an FDA approved device comprised of an interactive touchscreen and diverse program options to challenge patients through the use of visual motor activities, visual and auditory processing, cognitive skills, and endurance training. The purpose of this study is to enroll a small group of adults currently undergoing inpatient rehabilitation, who were admitted for an acute neurological event and present with an acute neurological visual field impairment. The primary objective is to compare any increase in visual field awareness using a prescribed regimen consisting of conventional vision exercises compared with a regimen using BITS touch screen technology. Participants will be alternately assigned into "A" and "B" groups upon enrollment. The control group "A" will be prescribed conventional (table top, pen and paper) vision interventions provided by an occupational therapist and will receive pre- and post- assessment of visual field awareness. Treatment group "B" will include a prescribed regimen with use of BITS touch screen technology. Group B participants will receive the same pre- and post- assessment of visual field awareness as Group A participants. The hypothesis is that incorporation of the BITS touch screen technology, being more interactive, will result in better outcomes for visual field awareness. This is an unblinded quasi-randomized control trial that will determine best treatment intervention for visual field impairment. Safety will be measured by the number of reported adverse events. The study period will include 6 sessions per participant, conducted at one site, with the objective of enrolling at least 30 participants to have 15 participants in each study group.