Moderate or Severe Vision Impairment, Both Eyes
Conditions
Keywords
portable electronic magnifiers
Brief summary
Over 1 million people in the UK suffer from untreatable visual impairment, many of them elderly. The major complaint of visually impaired people is their inability to carry out simple tasks, especially those involving reading. It is known that this activity limitation is a major cause of depression in an older population, and it is reflected in reduced quality of life. Low vision clinics, mostly based within hospital ophthalmology departments, dispense optical magnifiers to allow patients to carry out these tasks again, but these devices do have limitations (unusual posture, short working distance, monocular viewing). Although electronic magnifiers have been around since the 1960s, they were initially very large and expensive. Recent advances in technology have brought about an explosion in the number and range of portable and moderately-priced aids, which can be used binocularly, in a natural working position: these are currently not available through the NHS. Evidence is needed as to whether these portable hand-held electronic magnifiers could offer a significant benefit to the majority of patients, and therefore whether they should be routinely dispensed in low vision clinics. The proposed study is a two-arm randomised crossover trial with existing users of optical magnifiers being assigned to use a hand-held electronic magnifier in addition to their existing devices for 2 months. Reading and task performance will be measured with the aid, and compared to the performance with optical aids, and the patient will be asked to report on the comparisons between the aids.
Interventions
PROCEDUREportable electronic magnifier
PROCEDUREoptical aids
Sponsors
National Institute for Health Research, United Kingdom
University of Manchester
Cardiff University
Bangor University
Manchester University NHS Foundation Trust
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 95 Years
Healthy volunteers
No
Inclusion criteria
* Patients of Manchester Royal Eye Hospital * Visual impairment secondary to range of stable ocular pathologies (no change in VA \> 2 lines in previous 6 months) * Currently possess a near vision optical magnifying device. * VA \<= 6/30 (\<=0.7 logMAR) and/or log contrast sensitivity \<=1.20
Exclusion criteria
* Current use of personal EVES device * Hearing inadequate to respond to verbal instruction * Habitual language not English * A physical disability preventing the participant from operating the device * A score of less than 19 on the Mini-Mental State Examination
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| usage of magnifiers | Change from baseline at 2 months and 4 months | Use of Manchester Low Vision Questionnaire to quantify device usage |
| reading speed | Change from baseline at 2 months and 4 months | Reading speed using the device assessed by MNREAD test |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| speed of performance of activities of daily living | Change from baseline at 2 months and 4 months | total time taken to performance 5 selected activities of daily living using aids if required |
| difficulty with near vision activities | Change from baseline at 2 months and 4 months | Use of NV-VFQ-15 questionnaire to self-rate difficulty in performance of near vision activities |
| health related quality of life | Change from baseline at 2 months and 4 months | Use of EQ-5D and VISQOL questionnaires to self-rate health-related quality of life |
| well-being | Change from baseline at 2 months and 4 months | use of WHO-5 questionnaire to self-rate wellbeing |
Countries
United Kingdom
Outcome results
None listed