None listed
Conditions
Brief summary
Orthokeratology contact lenses are specialised rigid contact lenses are worn overnight and are removed in the morning. During overnight wear, orthokeratology lenses temporarily change the shape of the front surface of the eye, or cornea, which acts to correct mild to moderate degrees of myopia, providing wearers clear unaided vision throughout the day. The renewal and regeneration of corneal cells are important for maintaining transparency of the cornea which is crucial for clear vision. Surrounding the clear cornea is the limbus or limbal region which contains the stem cells that are responsible for maintaining renewal and regeneration of corneal cells and thus it's clarity. Previous studies have demonstrated changes to the limbal stem cells associated with soft contact lens wear. A deficiency in limbal cells can lead to decreased vision. Although orthokeratology lenses have a smaller overall diameter than soft contact lenses, its proximity to the limbus and rigid nature of the lens raises the question of whether there are any mechanical impacts on the limbal region associated with lens movement which may lead to changes in limbal stem cells. This study aims to investigate if there are any associated limbal changes with orthokeratology lens wear.
Interventions
Medical device: TGA approved Paragon CRT orthokeratology contact lenses (ARTG no.299388). These lenses will be made from Paragon HDS100 material which has high oxygen permeability (101 Dk units ISO/Fatt).
Exposure: 2 weeks of overnight lens wear during sleep (for minimum 7-8 hours) with no daytime lens wear.
Delivery: The research team will initially insert the lens on the subject's eye at the School of Optometry and Vision Science, UNSW, Sydney. Reseach participants will then be taught one-on-
Medical device: TGA approved Paragon CRT orthokeratology contact lenses (ARTG no.299388). These lenses will be made from Paragon HDS100 material which has high oxygen permeability (101 Dk units ISO/Fatt). Exposure: 2 weeks of overnight lens wear during sleep (for minimum 7-8 hours) with no daytime lens wear. Delivery: The research team will initially insert the lens on the subject's eye at the School of Optometry and Vision Science, UNSW, Sydney. Reseach participants will then be taught one-on-one face-to-face how to insert, remove, clean and maintain the orthokeratology lenses so that they can safely wear contact lenses during the trial period. Compliance: Text-message reminders will be sent to monitor adherence to the intervention.
Sponsors
University of New South Wales
Study design
Allocation
Non-randomised trial
Primary purpose
Treatment
Eligibility
Sex/Gender
All
Age
18 Years to 40 Years
Healthy volunteers
No
Inclusion criteria
1. Healthy individuals aged between 18-40 2. Have short-sightedness (myopia) between -1.ooD and -6.ooD and less than -1.50D of corneal astigmatism 3. No previous soft or rigid contact lens wear 4. Have good ocular health and general health 5. No contraindications to rigid contact lens wear
Exclusion criteria
1. Systemic or ocular conditions that may affect tear quality or contact lens wear 2. Previous history of ocular surgery, trauma, or chronic ocular disease 3. Ocular or systemic medication use that may interfere with contact lens wear or ocular surface 4. Previous reactions or allergies to any ocular medications 5. Not willing to comply with the allocated treatment and follow-up schedule
Outcome results
None listed