Eye Diseases: Amblyopia Eye Diseases Amblyopia
Conditions
Interventions
Participants will be pre-adapted to the appropriate refractive correction. Following a telephone interview, potentially suitable patients with amblyopia will be invited to attend the Institute of Opto
Sponsors
Record Provided by the NHSTCT Register - 2006 Update - Department of Health
Eligibility
Inclusion criteria
Inclusion criteria: 1. No personal history of epilepsy. 2. Willing to attend the Institute of Optometry for the 1-2 pre-treatment appointments, the post treatment assessment, and the follow-up assessment 3. Access to a computer for six approximately weekly sessions for the treatment. Ideally, the treatment will take place on a home computer in a dimly lit room, to simulate the lighting in which IPS is conventionally carried out. 4. Unilateral amblyopia with visual acuity better than 6/36 but worse than 6/9 in the amblyopic eye and 6/6 or better in the non-amblyopic eye. 5. Amblyogenic factor: amblyopic eye is either strabismic or has at least 1D more hypermetropia or 2D more astigmatism than the non-amblyopic eye. 6. No ophthalmoscopically detectable anomalies of fundus or defects of the visual pathway. This will be taken to mean no clinically significant departure from a normal ophthalmoscopic appearance and 30 degree visual fields (static perimetry) within normal limits. 7. Patients must be at least 10 years old and have signed the informed consent form, or have this signed by a parent or guardian if under 16 years old. 8. No history of strabismus or other cause of reduced visual acuity (e.g., cataract) in first two years of life 9. Able and willing to meet the costs of any refractive correction). Anisometropic participants will be encouraged to wear contact lenses as this has been shown to be the best option to minimise aniseikonia (Winn et al., 1988). The study will continue until there are 30 participants in each group.
Exclusion criteria
Exclusion criteria: 1. Personal history of epilepsy 2. Inability to attend Institute of Optometry for the 1-2 pre-treatment appointments, the post treatment assessment, and the follow-up assessment 3. No access to a computer for six approximately weekly sessions for the treatment 4. Unilateral amblyopia worse than 6/36, or better than 6/9 in the amblyopic eye or worse than 6/6 in the non amblyopic eye. Refractive amblyopia where the amblyopic eye has less than 1D more hypermetropia or 2D astigmatism than the non amblyopic eye. Any ophthalmoscopically detectable anomalies of fundus or defects of the visual pathway (30° visual fields by static perimetry outside within normal limits) 5. Patients under 10 years old 6. History of strabismus or other cause of reduced visual acuity in first 2 years of life 7. Unable or unwilling to meet costs of refractive correction
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| The conventional IPS treatment involved tracing on perspex slides placed over a red flashing background of various shapes and patterns, designed to stimulate different types of receptive fields in the visual system. The treatment is carried for weekly 30 minute sessions during which the better eye is patched. Patching does not take place at other times. This treatment is very tedious for the patient and a new computerised version has been developed. Our proposed study will evaluate this new computerised version of the IPS treatment. It has been claimed that IPS is effective because (a) it forces the person to use their amblyopic eye whilst carrying out detailed visual tasks, (b) the flashing stimulus promotes foveal fixation, and (c) the red background promotes foveal fixation. Although our previous study shows the treatment to be effective, it is unclear whether (b) and (c) are important in the treatment. It is possible that there is nothing special about IPS and the only way in which the treatment is helpful is through having the patient carry out a detailed visual task with the amblyopic eye. The aim of the proposed research is to compare the full computerised IPS treatment (with a red flashing stimulus) with a control IPS treatment that lacks a red and flashing stimulus. | — |
Secondary
| Measure | Time frame |
|---|---|
| Not provided at time of registration | — |
Countries
United Kingdom
Outcome results
None listed