None listed
Conditions
Brief summary
Despite decades of advancements in lens technology to improve wearability and safety, contact lens (CL) discomfort remains a persistent challenge (at ~50% discontinuation). The primary reason is due to CL wear discomfort. The underlying mechanisms leading to CL wear discomfort remains poorly understood, although inflammatory processes have been implicated. Using advanced imaging techniques, with the Heidelberg HRT3 with Rostock Corneal Module, known as static and Functional In Vivo Confocal Microscopy (Fun-IVCM), this study will characterise the features of human corneal immune cells during soft silicone hydrogel CL wear, during typical daily wear (i.e., at timepoints over a diurnal cycle). This will be achieved by quantifying the density, morphology and dynamics of corneal immune cells in habitual asymptomatic and symptomatic CL wearers, as well as healthy controls who do not regularly wear CLs. The main aim of the study is to determine the relationship between corneal immune cell features and soft CL discomfort. The intervention will also be applied to assess whether there is a difference in the diurnal features of corneal immune cells with short-term lens wear (i.e., among a group of non-contact lens wearers who will wear the intervention for one day) relative to habitual contact lens wearers (comprising both individuals who are asymptomatic and symptomatic when wearing their existing/own contact lens products). The study will also assess whether anaesthetic, used as a standard procedure for in vivo confocal imaging, affects corneal immune cells. We will recruit 45 adult participants, aged 18-45 years, comprising healthy controls who do not wear CLs (n=15), as well as habitual asymptomatic (n=15) and habitual symptomatic soft CL wearers (n=15).
Interventions
The study interventions comprise Johnson and Johnson Acuvue Oasys 1-day with HYDRALUXE spherical and/or Johnson and Johnson Acuvue Oasys 1-day with HYDRALUXE for astigmatism contact lenses. Both products are commercially available contact lenses. Contact lenses as close to the participants eye prescription (i.e. can be either spherical or astigmatism lenses), will be applied by study researchers who are optometry trained, onto both eyes.
In the context of this study, these products will be appl
The study interventions comprise Johnson and Johnson Acuvue Oasys 1-day with HYDRALUXE spherical and/or Johnson and Johnson Acuvue Oasys 1-day with HYDRALUXE for astigmatism contact lenses. Both products are commercially available contact lenses. Contact lenses as close to the participants eye prescription (i.e. can be either spherical or astigmatism lenses), will be applied by study researchers who are optometry trained, onto both eyes. In the context of this study, these products will be applied as interventions for use during corneal in vivo confocal microscopy imaging, and for short-term (one day wear of) contact lens correction. These will be compared with those who are regular contact lens wearers who will wear their own contact lenses during the study, except at Visit 1, where all participants will have a Johnson and Johnson Acuvue Oasys 1-day with HYDRALUXE spherical and/or Johnson and Johnson Acuvue Oasys 1-day with HYDRALUXE for astigmatism applied to their eyes depending on their eye prescription. The study will also quantify the effect of the contact lens interventions in the context of evaluating whether the use of topical anaesthetic, 1-2 drops of non-preserved oxybuprocaine hydrochloride 0.4% (being a standard procedure), during corneal in vivo confocal microscopy affects quantified features of corneal immune cells. Participants will undergo corneal in vivo confocal microscopy imaging using the Heidelberg HRT3 with Rostock Corneal module, by a study researcher, at every visit for a total of 5 visits. Imaging will be performed on the right eye only for approximately 30 minutes. Participants will attend five study visits in total over about 20 days, comprising 3 visits in the morning (AM: 08:00 AM – 10:00 AM) and 2 visits in the late afternoon (PM: 16:00 PM – 18:00 PM), conducted at the University of Melbourne. Participants will undergo comprehensive anterior eye evaluation procedures, including corneal static and Fun-IVCM imaging, and tear collection for subsequent compositional and functional analysis. Visit 1 will involve a comprehensive anterior eye assessment and corneal in vivo confocal microscopy imaging conducted immediately after applying soft contact lenses (similar to the participant's eye prescription) to the eyes of participants in both the control and habitual CL wearing groups, without the use of an anaesthetic eye drop. This will be used as a comparator to assess whether the anaesthetic eye drops, which are conventionally used to numb the surface of the eyes prior to corneal in vivo confocal microscopy imaging, may have an impact on corneal immune cells. At Visit 2 AM and Visit 3 PM of the same day, the baseline diurnal patterns of corneal immune cell features will be compared between controls (non-contact lens wearers) and habitual asymptomatic and habitual symptomatic contact lens wearers, without the presence of a contact lens. At Visit 4 AM and Visit 5 PM, the control group will also be fitted with soft contact lenses, by researchers who are optometry trained, similar to their prescription for the duration of the day (~8 hours following lens application) to evaluate the impact of short-term (one day) wear of contact lenses on immune cell features, relative to habitual (long-term) contact lens wearers, comprising both asymptomatic and symptomatic wearers). The applied soft contact lenses will be removed by study researchers and discarded appropriately.
Sponsors
The University of Melbourne
Study design
Allocation
Non-randomised trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Investigator)
Eligibility
Sex/Gender
All
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
All participants must fulfil all of the following inclusion criteria to be eligible for the study, at the Screening Evaluation Visit: 1. Male or female aged 18 to 45 years, with full legal capacity to volunteer; 2. Provide written informed consent to participate; 3. regularly wear a form of vision correction such as glasses and/or daily disposable silicone hydrogel contact lenses for everyday activities, or have a very mild prescription such that glasses may not be needed for functional distance vision (*Note: if you only have reading glasses and do not need a form of vision correction for distance tasks, you are not eligible for this study); 4. Can understand and follow study instructions, with the intention of completing all required study visits; 5. Habitual binocular distance visual acuity (whether unaided or with a form of non-CL optical correction) of at least 6/12; 6. BCVA of at least 6/9 in each eye; 7. Have typical sleeping patterns, defined generally as obtaining at least 6 hours of sleep per night, with sleep onset time between 21:00 PM and 2:00 AM, and waking up between 05:00 AM and 09:00 AM, by self-report; 8. Have at least 3 T cells in either the whorl or inferior cornea within the imaging field of view on IVCM; 9. Willing, or has demonstrated ability to tolerate the application and wear of soft CLs; 10. A spectacle refraction of within ±6.00 DS and astigmatism less than or equal to 2.50 DC in each eye; 11. Be sufficiently proficient in English to understand the study details, instructions, and answer questions from the study researcher, and the study questionnaires; 12. Additional inclusion criteria for control participants (at the Screening Evaluation Visit) o Have not worn CLs consistently (i.e., more than once per week) over the three months prior; o Does not have a prior history of being a lapsed prior CL wearer (e.g. had worn CLs consistently for more than 6 months in the past). 13. Additional inclusion criteria for habitual CL wearing participants (at the Screening Evaluation Visit): o Have worn daily disposable silicone hydrogel soft CLs consistently (i.e., average of 4 or more days per week) for at least 6 months prior to Visit 1; o Willing to continue wearing the same type and brand of habitual CLs for the duration of the study; o Meets the criterion to either be a ‘symptomatic’ CL wearer (i.e., has a score for Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) of 13 or more) or ‘asymptomatic’ CL wearer (i.e., CLDEQ-8 score of 9 or less).
Exclusion criteria
Exclusion criteria for all participant groups (at the Screening Evaluation Visit): 1. Any known active ocular disease and/or infection (including dry eye disease); 2. Any of the following conditions: active ocular inflammation, active ocular allergy, a corneal disorder or abnormality that could affect corneal sensitivity or normal spreading of the tear film (except superficial punctate keratitis), severe blepharitis or obvious inflammation of the eyelid margin, which in the judgment of the investigator may interfere with the interpretation of the study results; 3. A clinically significant injury to either eye in the 12 weeks prior to enrolment; 4. Ocular surgery within the past six months at baseline, or has ocular surgery planned over the course of participation in the study; 5. Prior history of laser refractive eye surgery; 6. A known allergy to, or previous reaction to, any eye drops required for the study; 7. The presence of significant corneal scarring or a physical factor that impairs the ability to perform corneal imaging; 8. Clinically significant dry eye disease, as specified in the TFOS DEWS II definition, is defined by dry eye symptoms (i.e., an Ocular Surface Disease Index (OSDI) score greater than or equal to 13, out of 100 AND one or more of the following clinical signs : a) Tear osmolarity of greater than or equal to 308 mOsm/L in either eye or interocular differences greater than 8mOsm/L; b) TBUT < 10 sec in either eye; c) Ocular surface staining: > 5 corneal spots, > 9 conjunctival spots, or eyelid margin (greater than or equal to 2 mm length and greater than or equal to 25% width) 9. Current use of any topical medications other than artificial lubricant eye drops (e.g., anti-allergy eye drops, anti-glaucoma medications, corticosteroids) or systemic medications that are known to affect the ocular surface (e.g., steroids, antibiotics, antidepressants, Roaccutane); 11. Has a systemic condition that significantly affects eye health (e.g., Sjogren’s syndrome, diabetes, high blood pressure or other), by self-report; 12. Has received a vaccination in the past two weeks, by self-report; 13. Any blood-born illnesses such as hepatitis or human immunodeficiency virus (HIV) that may affect the eyes, by self-report; 14. Females who are pregnant or breastfeeding at the time of study enrolment or who plan to become pregnant during the study, by self-report; 15. Unable to sit/lie supine comfortably during the examination procedures; 16. Participation in an interventional clinical trial within the previous 30 days, or currently enrolled in an interventional clinical trial; 17. Current shiftwork and/or recent cross-time zone travel in the last month, or such anticipated travel during the study period; 18. For habitual CL wearers, unwilling to go without CLs as required for the study; 19. A condition or situation that, in the opinion of the study investigator, will limit the potential participant’s ability to comply with the study protocol, might adversely affect their safety or substantially confound the study outcomes.
Outcome results
None listed