Exploring the Psychophysics of Keratoconus Using the Moorfields Acuity Chart (NCT02429609) | Clinical Trial Compass
CompletedNot Applicable
Exploring the Psychophysics of Keratoconus Using the Moorfields Acuity Chart
80 participantsStarted 2015-04-15
Plain-language summary
The measurement of visual acuity is made using black letters of varying size superimposed on a uniform white background. The objective is to determine the smallest letter, or optotype, that can be correctly identified. One limitation of current tests is the variability of measurements, this making it difficult for clinicians to determine if changes in visual acuity are related to ocular disease. This variability has been attributed to the design of current optotypes, in particular their differing legibilities. Our group has recently demonstrated that a new type of letter chart (Moorfields Acuity Chart), containing letters with a black core and a white border presented on a grey background, reduces the variability of visual acuity measurements. In this study the investigators wish to determine if changes in vision owing to keratoconus, a disease that causes the cornea to adopt an irregular shape, may be detected more easily using the Moorfields Acuity Chart compared with conventional letter charts.
Who can participate
Age range
18 Years – 35 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Keratoconic subjects (50):
* Age 18-40 years.
* The presence of keratoconus in at least one eye.
* The absence of significant media opacities (e.g. cataract, corneal scarring).
* The absence of any other ocular pathology (e.g. glaucoma, diabetic retinopathy, uveitis).
* The absence of amblyopia in the test eye.
* No previous ocular surgery (e.g. corneal crosslinking, cataract surgery, etc.)
* Best corrected visual acuity better than or equal to 6/60 (1.0 logMAR).
* Pupil diameter ≥3 mm and ≤7 mm in normal room illumination.
Healthy subjects (30):
* Age 18-35 years.
* The absence of clinically significant keratoconus.
* The absence of significant media opacities. (e.g. cataract, corneal scarring).
* The absence of any other ocular pathology (e.g. glaucoma, diabetic retinopathy, uveitis).
* The absence of amblyopia in the test eye.
* No previous ocular surgery (e.g. corneal crosslinking, cataract surgery, etc.)
* Best corrected visual acuity better than or equal to 6/9 (0.1 logMAR).
* Pupil diameter ≥3 mm and ≤7 mm in normal room illumination.
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
The relative difference in visual acuity measurement between subjects with and without keratoconus when examined with different types of visual acuity chart.
Timeframe: 9 months
Trial details
NCT IDNCT02429609
SponsorMoorfields Eye Hospital NHS Foundation Trust