Comparison of Tear Evaporation Rate With DAILIES TOTAL1 and Biotrue ONEday

Not Applicable

Completed

Brief Summary: The purpose of this pilot study is to compare the effect of DAILIES TOTAL1, a low water content silicone hydrogel lens, and Biotrue ONEday, a high water content hydrogel lens, on the rate of tear evaporation. The study will also serve to validate the novel, in-house developed evaporimeter.

Recruitment & Eligibility

Inclusion Criteria

Is at least 17 years of age and has full legal capacity to volunteer;
Has read and signed an information consent letter;
Is willing and able to follow instructions and maintain the appointment schedule;
Has worn soft contact lenses for a minimum of 6 months;
Currently wears soft contact lenses for at least 4 days per week and 8 hours per day;
Has an acceptable fit and comfort with both study contact lenses in the powers available;
Has less than or equal to 1.00DS difference between eyes in their habitual contact lenses;
Is willing to be awake for at least 2 hours before visit 2;
Is willing to not wear eye makeup on the day of visit 2 and 3;
Is willing to not use eye drops or artificial tears on the day of visits 1, 2, and 3;
Has a wearable pair of spectacles.

Exclusion Criteria

Is participating in any concurrent clinical or research study;
Has any known active* ocular disease and/or infection;
Has a systemic condition that in the opinion of the investigator may affect a study outcome variable;
Is using any systemic or topical medications that in the opinion of the investigator may affect a study outcome variable;
Has known sensitivity to sodium fluorescein dye;
Is pregnant, lactating or planning a pregnancy at the time of enrolment (by verbal confirmation at the screening visit);
Is aphakic;
Has undergone refractive error surgery;
Has a known sensitivity to petroleum jelly (Vaseline);
Has epilepsy and/or a sensitivity to flashing lights;
Wears toric contact lenses;
Has any physical impairment that would interfere with holding the evaporimeter;
Has taken part in another research study within the last 14 days.

Arm && Interventions

Group	Intervention	Description
Nesofilcon A/Delefilcon A	Delefilcon A	Nesofilcon A was worn in right eye and delefilcon A worn in the left eye.
Delefilcon A/Nesofilcon A	Delefilcon A	Delefilcon A was worn in right eye and Nesofilcon A worn in the left eye.
Nesofilcon A/Delefilcon A	Nesofilcon A	Nesofilcon A was worn in right eye and delefilcon A worn in the left eye.
Delefilcon A/Nesofilcon A	Nesofilcon A	Delefilcon A was worn in right eye and Nesofilcon A worn in the left eye.

Primary Outcome Measures

Name	Time	Method
Tear Evaporation Rate With Nesofilcon A	Baseline, 15 minutes post-contact lens, 6 hours post-contact lens	Tear film evaporation rate (% relative humidity per second) was performed using a novel evaporimeter as a non-invasive measurement of tear film evaporation. The slope was calculated from the change in humidity between 7 to 17.5 seconds while the eye was open and between 10 to 17.5 seconds when the eye was closed. Data from the both eyes were analyzed.
Tear Evaporation Rate With Delefilcon A	Baseline, 15 minutes post-contact lens, 6 hours post-contact lens	Tear film evaporation rate (% relative humidity per second) was performed using a novel evaporimeter as a non-invasive measurement of tear film evaporation. The slope was calculated from the change in humidity between 7 to 17.5 seconds while the eye was open and between 10 to 17.5 seconds when the eye was closed. Data from the both eyes were analyzed.

Secondary Outcome Measures