CompletedNot Applicable

Validation of Innovative Scheimpflug Topography Derived RGP Contact Lens Designs In Optometry Network

United Kingdom120 participantsStarted 2022-06-06

Plain-language summary

The goal of this Prospective, single-site, cohort study is to validate rigid gas permeable corneal contact lens (RGP) designs for keratoconus derived from combining the data from corneal topography scans and contact lenses ordered in patients with keratoconus (KC) attending a UK tertiary NHS Hospital contact lens clinic. The main questions it aims to answer are: * Does a Scheimpflug topography derived RGP contact lens design for keratoconus have the equivalent overall contact lens fit as the patients' own lens? * Is the number of trial lenses required to fit a patient is reduced compared to standard practice? * Is the time taken to fit a contact lens is reduced compared to standard practice? * Is there user acceptance of the new lens? * Are the Axial ege lift (AEL) changes clinically significant? There will be 3 work packages WP1: For each participant data collection will take place over two visits. • Visit 1: Pentacam topography scans and optimal 'virtual' lens selection will take place. • • Visit 2: Participants are fitted with 4 contact lenses (i) the optimal lens design as specified by the virtual fitting module, (ii) a contact lens with a clinically significant step flatter AEL (iii) a contact lens steeper in axial edge lift (AEL) (iv) the participant's own contact lens. Each CL fit will be assessed with slit lamp photography according to the standardised method proposed by Wolffsohn et al. (2013), Anterior segment OCT MS39) (CSO Hansom Instruments, UK) and best-corrected visual acuity with each lens design using high-contrast logMAR . WP2. Participants will attend one appointment where a traditional lens fit, and a lens fitted using the topography guided 'virtual' module will be undertaken (with the fitting method selected for each eye randomised). For each fitting method the total fitting time will be measured and the total number of trial contact lenses used. Patients will be invited to complete a questionnaire that probes their satisfaction of this process. WP3. Clinicians not involved in the study will be invited to examine a demo version of the virtual fitting module and complete the validated system usability scale tool.

Who can participate

Age range

18 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.

Inclusion Criteria: * \- WP1: * (a) Presence of keratoconus in either eye * (b) Currently using a rigid gas permeable contact lens correction * (c) Male or female, aged 18 years or older * (d) The absence of significant media opacities * (e) No ocular pathology other than keratoconus * (f) Ability to understand nature/purpose of the study and to provide informed consent * (g) Ability to follow instructions and complete the study * (h) Ability to speak English * WP2: * (a) Presence of keratoconus in both eyes * (b) Male or female, aged 18 years or older * (c) The absence of significant media opacities * (d) No ocular pathology other than keratoconus * (e) Ability to understand nature/purpose of the study and to provide informed consent * (f) Ability to follow instructions and complete the study * (g) Ability to speak English * WP3: * (a) Optometrist, dispensing optician or ophthalmologist registered with the General Optical Council * (b) Works within contact lens service at Moorfields Eye Hospital * (c) Ability to understand nature/purpose of the study and to provide informed consent * (d) Ability to follow instructions and complete the study * (e) Ability to speak English . Exclusion Criteria: * \- WP1: * (a) Any systemic disease likely to affect visual performance * (b) Any ocular disease that may affect visual performance, other than keratoconus * (c) Hearing impairment sufficient to interfere with hearing instructions * (d) Poor understanding of English language and/or …

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

Rigid gas permeable contact lens fit

Timeframe: 18 months

Trial details

NCT IDNCT06312163

SponsorMoorfields Eye Hospital NHS Foundation Trust

Sponsor typeOTHER

Study typeOBSERVATIONAL

Primary completion2023-12-15

View on ClinicalTrials.gov More Keratoconus trials