Conditions: Aqueous Deficient Dry Eye Meibomium Gland Dysfunction
Keywords: Aqueous deficient dry eye (ADDE) Meibomium Gland Dysfunction (MGD) Normal/Control (Non Dry Eye)
Allocation: NON_RANDOMIZED | Intervention model: PARALLEL
Enrollment: 15
Healthy volunteers: yes

Brief summary:
Compare the objective tear film dynamic measurements in three different populations (MGD \[Meibomium Gland Dysfunction\], ADDE \[Aqueous Deficient Dry Eye\] and normal/control \[non-dry eye\]) and the subjective experience before and after instilling a single drop of saline in each eye.

Currently available office-based tests for dry eye do not reliably correlate with patients' subjective symptoms. This study is interested in assessing how individuals with these two different ocular surface diseases compare with the normal population when measured objectively using two different instruments.

Detailed description:
There will be one study day with a single visit that will consist of taking two sets of measurements. Baseline measurements are taken in both eyes using a wavefront sensor to measure visual quality followed by saline instillation. Five minutes after drops, visual quality is again measured to evaluate changes in tear dynamics.

Arms:
arm 1: Non-Dry Eye patient population (intervention remains the same across all arms) arm 2: Meibomium Gland Dysfunction population(intervention remains the same across all arms) arm 3: Aqueous Deficient Dry Eye population(intervention remains the same across all arms)

Interventions: intervention 1: Subjective Questionnaire intervention 2: Measurement with wavefront sensor (right eye, then left eye) intervention 3: Instill Saline Drop
Intervention descriptions: intervention 1: The team will use a one page questionnaire to obtain subjective input before the first set of measurements and after instilling the Saline drop. intervention 2: The wavefront instrument measures the eye's ability to create a sharp image by briefly shining a laser light from the wavefront sensor into the eye and measuring the light that bounces back through the cornea. For these measurements, subjects will sit on a chair and be instructed to place their chin in a chin rest and lean their forehead against a forehead rest. The subject will be instructed to hold his/her head steady, look in a certain direction, blink or not blink. We will obtain the measurements over a short period of up to approximately 45 seconds. We will start recording data asking the subject to either blink naturally or to hold his/her eye open for a few (up to 10) seconds, and repeat the blink and hold sequence usually for up to four times. intervention 3: One drop will be instilled in both eyes and patient will wait 5 minutes prior to repeating the questionnaire and wavefront sensor. A single drop is approximately 30 µL and will be placed into the inferior cul-de-sac while the patient looks up.

Protocol document: