Effects of Anti-Glaucoma Medications on the Ocular Surface

The purpose of the study is to compare the efficacy of FDA-approved Travoprost (Travatan Z) and Latanoprost (Xalatan)as anti-glaucoma treatment. Several studies indicate that glaucoma medications may be associated with decreased tear production and tear film break-up time (TBUT), and increased inflammatory cells in the conjunctiva (membrane lining of the eye lids and the covering of the eye) leading to dry eye. Normal tear film (coating of the eye) is continuous and blinking maintains the tear film continuity. If you keep your eyes open long enough without blinking, the tear film will start breaking up. Your eye will feel uncomfortable forcing you to blink. In patients with dry eyes, the tear film is unstable, and breaks up faster. Therefore the tear break up time in patients who have dry eyes is shorter.

In this study, the investigators will be comparing the two previously mentioned FDA-approved eye drops Latanoprost and Travoprost. The difference between the two medications is a preservative called benzalkonium chloride (BAK). Latanoprost contains BAK while Travoprost does not. The investigators will be comparing the efficacy of each medication in lowering IOP as well as trying to track the density of immune cells across the corneal surface by taking photos of your eye. The investigators will also be assessing whether either drop leads to symptoms of dry eye by comparing results from ocular surface exam tests such as TBUT.

The purpose of the study is to compare the early effects of two anti-glaucoma eye drops on eye pressure and inflammation of the eye using a microscope. One of the eye drops contains a commonly used preservative, benzalkonium chloride (BAK), while the other is free of this preservative, instead it utilises a new ionic buffer system called SofZia. Prolonged use of BAK may be damaging to the eye surface and thus being investigated at a microscopic level in this study.

Specific aims are to assess the in vivo effect of topical BAK-containing and BAK-free prostaglandin analogue anti-glaucoma therapy on intraocular pressure (IOP), as well as on density and morphology of corneal immune cells, epithelial cells and sub-basal nerve plexus.

Eligibility Criteria:
Inclusion Criteria:

* Subjects must be 18 years of age and may be of any race and either gender;
* Subjects must not have ever used topical prostaglandin anti-glaucomatous therapy;

  * Subject has not used anti-glaucomatous treatment in the past 30 days and has not been using prescribed anti-glaucomatous medication for more than 6 months.
  * Subject is using other topical anti-glaucomatous topical treatment and wants to switch to a prostaglandin (must have undergone 30 day washout period)
* The IRB Approved informed consent and the privacy document must be read, signed, and dated by the subject or legally authorized representative before enrollment. Additionally, the informed consent document must be signed and dated by the individual consenting the subject, as well as signed and dated by a witness, if applicable;
* Subjects must be generally healthy and have normal ocular health; and
* Subjects must be willing to follow the study procedures and visit schedule.

Exclusion Criteria:

* Subjects must not have known sensitivities to any ingredient in any of the test articles
* Subjects must not have any systemic or ocular disease or disorder (exc refractive error), complicating factors or structural abnormality that would negatively affect the conduct or outcome of the study:

  * No prior (within 30 days of enrollment) or current ocular infections (bacterial, viral or fungal), active ocular inflammation (i.e., follicular conjunctivitis, allergic conjunctivitis, iritis), glaucoma, or preauricular lymphadenopathy.
  * No clinically significant lash or lid abnormality (e.g., trichiasis, entropion or ectropion).
  * No uncontrolled systemic disease or debilitating disease (e.g. cardiovascular disease, hypertension, diabetes, or cystic fibrosis.).
  * No prior (within 7 days of enrollment) or current, unstable active illness (e.g., upper respiratory infection).
* Pregnant woman
* Subjects must not have history of ocular surgery/trauma within the last 6 months
* Subjects must not have used any topical ocular or systemic antibiotics within 30 days of enrollment continuing throughout the study
* Subjects must not have used any topical ocular or systemic corticosteroids within 30 days of enrollment continuing throughout the study
* Subjects must not have used immunomodulator medications within 30 days of enrollment continuing throughout the study
* Subjects must not have a immune cell density of \>60/fame present at their baseline confocal scan
* Subjects must not have participated in any other ophthalmic drug or device clinical trial within 30 days of enrollment.
* Inability to cooperate with the confocal exam