Restoration vs. Compensation in Neurovisual Rehabilitation of Visual Field Defects

Study Overview
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Brief Summary
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Visual field defects (VFD) are a frequent effect of cerebral lesions especially after posterior cerebral artery stroke. The present study was conducted to compare effects of vision restoration training (VRT) and compensation training (Visual Exploration Training, VET) on visual field performance.

Conditions
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Hemianopia, Brain Injuries, Traumatic

Intervention / Treatment
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* Behavioral: Vision Restoration Training (VRT)
* Behavioral: Vision Exploration Training (VET)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Visual field defects after brain damage lesion age above 6 months documented brain lesions due to ischemic stroke, hemorrhage or tumor demonstrated by computer tomography or by magnet resonance imaging Exclusion Criteria: hemispatial neglect complete blindness severe psychotic diseases serious drug abuse chronic degenerative diseases (dementia, multiple sclerosis) severe motor impairments noticeable low intelligence influencing proper comprehension of diagnostic and training instructions considerable impaired vision (visual acuity below 0.1 generated by amblyopia, opacity of cornea or lens, maculopathy and other retinal diseases where vision impairment is expected in the next month (e.g. subretinal neovascularisation, retinitis pigmentosa, diabetic retinopathy) inability to fixate due to central scotoma, pathological nystagmus or other forms of fixation disabilities

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vision Restoration Training (VRT)<br>home-based rehabilitation program which applies intense light stimulation via a PC-monitor to areas of residual vision with a duration of 1 hour daily/six days a week, subjects are asked to respond via button press upon appearance of light stimuli without eye movements | Behavioral: Vision Restoration Training (VRT)<br> <br> |
| Active Comparator: Vision Exploration Training (VET)<br>home-based rehabilitation program to train eye movements upon visual stimuli presented via a PC-monitor with a duration of 1 hour daily/six days a week, subjects are asked to shift their gaze towards targets and respond via button press upon detection of targets | Behavioral: Vision Exploration Training (VET)<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| High Resolution Perimetry - Detectection performance change before vs. after training (%) |  | 3 months | 
| Humphrey Field Analyzer (Static Perimetry) - Detectection performance change before vs. after training (%) |  | 3 months |