Clinical trial NCT02806921: Changes in the Tear Film With Scleral Contact Lens Wear for Keratoconic Eyes
Official title: Protease and Cytokine Composition in Post Lens Tear Reservoir of Scleral Lenses for Keratoconic Eyes
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Keratoconus
Keywords: Scleral Contact Lens
Tear Proteases
Tear Cytokines
Lead sponsor: University of Waterloo
Sponsor class: OTHER
Collaborators: name: Bausch & Lomb Incorporated
First posted: 2016-06-21
Enrollment: 13
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to investigate changes in the level of inflammatory mediators in the tear film of scleral contact lens wearers in a keratoconic population.

Detailed description: Scleral contact lenses are rigid gas permeable lenses designed to rest on the sclera while vaulting over the cornea with a fluid reservoir. The use of scleral contact lenses has become the current standard of practice as a nonsurgical management of corneal ectasia and ocular surface diseases. Cases have been recently presented of scleral lens wearers exhibiting adverse corneal findings and conjunctival injection from lens wear. These findings are likely associated with the mechanical and hypoxic effects due to poor fitting characteristics at the limbal area. Tear film analysis detecting changes in the levels of proteinases and cytokines have helped researchers gain a better understanding of the pathophysiology of complications in soft contact lenses wearers, dry eye, and keratoconus. Ultimately, this study will provide insights in relating scleral lens fitting characteristics and corneal and limbal physiological responses.

Eligibility criteria: Inclusion Criteria:

* Had been diagnosed with keratoconus in at least one eye.
* Is at least 18 years of age and has full legal capacity to volunteer.
* Has read and understood the information consent letter.
* Is willing and able to follow instructions and maintain the appointment schedule.

Exclusion Criteria:

* Is using any topical medications that will affect ocular health.
* Has any ocular pathology or severe insufficiency of lacrimal secretion (severe dry eyes) that would affect the wearing of contact lenses.
* Has persistent, clinically significant corneal or conjunctival staining using sodium fluorescein dye.
* Has any clinically significant lid or conjunctival abnormalities and active neovascularization.
* Is aphakic.
* Has undergone any corneal surgery.
* Is participating in any other type of eye related clinical or research study.
* Has any known allergies or sensitivity to the diagnostic pharmaceuticals or products, such as fluorescein, used in this study.

Primary outcomes:
measure: Tear Protein
timeFrame: 2 weeks of lens wear with daily schedule of 6-8 hours.
Secondary outcomes:
measure: Comfort
timeFrame: 2 weeks of lens wear with daily schedule of 6-8 hours.
measure: Bulbar and limbal hyperemia
timeFrame: 2 weeks of lens wear with daily schedule of 6-8 hours.
measure: Corneal thickness
timeFrame: 2 weeks of lens wear with daily schedule of 6-8 hours.
Other outcomes:
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Study officials:
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