Hemianopia, a form of homonymous visual field defects restricted to one side of the visual field (either left or right), due to acquired post-chiasmatic brain injury Eye Diseases
Conditions
Interventions
Compensatory scanning training: teaching patients to make systematic compensatory eye movements. Both groups receive the same intervention. Training group is tested before and after the intervention,
Sponsors
University of Groningen
Eligibility
Sex/Gender
All
Inclusion criteria
Inclusion criteria: 1. Homonymous visual field defects (quadrantanopia at minimum, three quarters affected at maximum, based on binocular Goldmann perimetry, isopters: V-4e, III-4e, I-4e, I-2e and I-1e, monocular Goldmann III-4e, and monocular Humphrey monocular 10-2), due to acquired post-chiasmatic brain injury. 2. At least six months between onset of HVFD and first effect measurement 3. Neurological condition is stable 4. Ophthalmological condition stable for at least six months 5. Age between 18 and 75 years 6. Self-reported mobility-related difficulties 7. Able to walk at least 50 meters independently or by using a cane/rollator, without a wheelchair (mobility assessment has to be possible, training is aimed at mobility in and around the house). 8. Best corrected binocular visual acuity 0.5 (Lighthouse ETDRS 2000 chart, 4m, 500 lux, using optimal correction). 9. Peak log contrast sensitivity within normal limits (Vistech VCTS6500, 4m, 500 lux, >B5 or C4) 10. Eye and head mobility undisturbed in all directions 11. MMSE score >25 12. Sufficient memory for remembering training instructions and homework assessments (based on 8WT)
Exclusion criteria
Exclusion criteria: 1. Only one functional eye 2. Unclear neurological cause of HVFD 3. Hemiplegia or quadraplegia 4. Psychiatric disorders influencing participation, mobility and compliance with training 5. Misuse of drugs/alcohol/medication 6. Severe hearing impairment; hearing aids allowed, verbal communication has to be possible. 7. Problems with balance or orientation impairing mobility 8. Visual field defect in ‘intact’ hemi-field not connected to the main visual field defect 9. Diplopia 10. Metamorphosis expected to influence scanning training (Amsler test) 11. Oscillopsia 12. Impairments in understanding (spoken) language (based on observation) 13. Severe agnosia (based on VOSP) that strongly influences the mobility problem, such as simultanagnosia 14. Severe impairments of executive functioning requiring an adapted training protocol 15. Severe unilateral neglect (based on Balloons, drawings, line bisection and Complex Rey Figure). 16. Severe memory disorders requiring an adapted training protocol 17. Strong deviance on Trailmaking, VOSP, and Balloons not explained by hemianopia 18. Strong deviance on drawings and Complex Rey Figure not explained by hemianopia 19. Optic ataxia 20. Sticky fixation (oculomotor apraxia)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Scanning strategy based on eye tracking (fixation and saccade parameters) on a dot counting task. Measured on all time points (i.e. early pre-assessment in control group, pre-assessment, post assessment) | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Visual functions: 1.1. Visual field, with Goldmann (2x monocular) 1.2. Visual acuity, with ETDRS 2000 letter chart at 500 lux 1.3. Contrast sensitivity, with Gecko at 500 lux 2. Questionnaires (see also F1.Questionnaires): 2.1. Awareness; based on theories on awareness by Crosson and Critchley and piloted in a group of patients with hemianopia. 2.2. Life events; questions based on the Life Events Questionnaire (LEQ). 2.3. Motivation; questions selected from Motivation for Traumatic Brain Injury Rehabilitation Questionnaire (MOT-Q). - only measured before onset of intervention. 2.4. Expectations (before intervention) /Evaluation (after intervention) of training; questions based on interviews from previous master thesis research at UMCG Beatrixoord. 2.5. NEI-VFQ25 (National Eye Institute - Visual Functioning Questionnaire/25 items, Dutch translation) 2.6. VOM (Vragenlijst Onafhankelijke Mobiliteit, Dutch translation of the Independent Mobility Questionnaire) 2.7. CVD (Cerebrale Visuele Stoornissen, Dutch translation by M. L. M. Tant, 1997) 3. Neuropsychological testing: 3.1. Grey Scales 3.2. NLV (Nederlandse Leestest voor Volwassenen) - only on first measurement 3.3. Zoo-map (BADS)) - only on first measurement 3.4. 15-Words Test) - only on first measurement 4. (Ecological) scanning and mobility tests: 4.1. Dot Counting Task (with eye tracking); dots are presented on a large screen and are to be counted by the patients. 4.2. Standardized search task (with eye tracking); search task on a large screen; patients have to indicate whether or not a target is present among distractors. 4.3. Hazard perception pictures (with eye tracking); photos of traffic sit | — |
Countries
Netherlands
Contacts
Public ContactGera de Haan
Outcome results
None listed