Visual and Functional Assessment in Low Vision Patients

Completed

• Conditions: Optic Nerve Pathology; Inherited Retinal Dystrophies; Retinitis Pigmentosa; Age-related Macular Degeneration

• Registration Number: NCT01876147
• Lead Sponsor: University of Oxford

Brief Summary

Vision testing is a fundamental part of every optometry and ophthalmology assessment. Traditional vision testing charts are not able to measure vision below a certain level. Vision in this range is classified as counting fingers (CF), hand movements (HM) and light perception (LP). These measures are not very accurate or easily quantifiable. They are also poorly understood in terms of impact on quality of life. This study aims to assess new methods for measuring the vision of patients with very low vision.

Detailed Description

Assessing very low vision accurately is becoming increasingly important with the increase in research in this area, such as using retinal implants to restore vision. Without being able to accurately measure the change in vision before and after treatment, it is not possible to fully assess the effect of treatment.

The Freiburg Vision Test (FrACT) is a computer based test developed to assess patients down to the LP level. It has been used in research in recent years. The FrACT is suitable for research but is not suitable for a clinical setting. The Berkeley Rudimentary Vision Test (BRVT) works on a similar principal as the FrACT but consists of hand held cards shown to the patient. Little work has been completed on how well the BRVT test works. Results from FrACT and BRVT will be compared in a group of patients with very low vision. This is important to establish how easily research results can be applied to a clinical setting.

Patients will also be asked to complete a daily living survey to better understand the impact of such poor vision on the ability to carry out day to day tasks. This understanding will help guide low vision services for patients as well as help direct low vision research to achieve a useful level of functional vision.

Study Timeline

• Study First Submitted: 2013-06-10
• Study First Submitted QC: 2013-06-10
• Study First Posted: 2013-06-12
• Study Start: 2013-08
• Primary Completion: 2016-03
• Study Completion: 2016-03
• Status Verified: 2018-10
• Last Update Submitted: 2019-06-12
• Last Update Posted: 2019-06-13

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

• Snellen VA or equivalent ≤ 6/60 in both eyes
• Patient has capacity to give consent and to undertake vision tests

Exclusion Criteria

• Diagnosis of functional vision loss
• Unwilling and/or unable to sign informed consent and complete the vision tests

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Comparison of VA measured with FrACT and BRVT vision tests	Single visit

Secondary Outcome Measures

Name	Time	Method
Relationship between VA and ability to carry out daily living tasks.	Single time point	Results from a daily living skills survey will be related to VA measured by FrACT testing.

Trial Locations

Locations (1)

Oxford University Hospitals NHS Trust; 🇬🇧 Oxford, Oxfordshire, United Kingdom