Comparison Between iLux™ and LipiFlow® in the Treatment of Meibomian Gland Dysfunction

Meibomian glands on the lower eyelid were assessed by the examiner using a Meibomian Gland Evaluator while viewing the eyelid margin using a slit lamp microscope. 5 glands in 3 zones (nasal, medial, temporal) were evaluated. Each gland was scored from 0-3 for a maximum MGS of 45 in each eye. MGS scoring was as follows: 0 = no secretion (worst), 1 = inspissated, 2 = cloudy, 3 = clear liquid (best). A positive change value indicates an improvement.

Tear break-up time (defined as the time required for dry spots to appear on the surface of the eye after blinking) was assessed by the examiner using a slit lamp and fluorescein strips. Fluorescein was instilled onto the patient's eye, after which the patient blinked three times, then kept the eye open. Immediately thereafter, the examiner used a stopwatch to record the time between the last blink and the first appearance of a dark spot on the cornea (formation of dry area). Three consecutive measurements were taken and averaged for actual TBT. A positive change value represents a lengthening in the tear break-up time and greater comfort.

The number of device- or procedure-related adverse events was calculated, including changes from baseline (Yes/No) in any of the following eyelid characteristics: lid margin assessment or development of floppy eyelids or entropion (eyelid rolled inward) or ectropion (eyelid sagging outward) or loss of lash integrity.

The Ocular Surface Disease Index (OSDI) is a 12-item, patient-reported outcome questionnaire used to measure ocular symptoms, visual function, and environmental factors that may affect a patient's vision. Each item is scored on a 0-4 Likert-type scale, where 0 is "None" and 4 is "All of the Time." The OSDI is calculated as the (sum of scores) x 25 / (# of questions answered), for a resultant overall score of 0-100, where 0 corresponds to no disability and 100 corresponds to complete disability. A negative change value indicates an improvement.

The patient placed a vertical line on visual analog scale questionnaire using a scale of 0-100 (0 = no pain, 100 = maximum pain) at the point that indicated the pain in or around their eyelids, or face during the procedure including feelings of pressure, tightness, heaviness, burning, and other negative sensations. A score a 20 was associated with a description of "hurts a little". Assessments were made at baseline (pre-treatment), immediately post-treatment, and Day 1 post-treatment. No formal hypothesis testing was pre-specified for this endpoint.

The patient placed a vertical line on visual analog scale questionnaire using a scale of 0-100 (0 = no discomfort, 100 = maximum discomfort) at the point that indicated the discomfort in or around their eyelids, or face during the procedure including feelings of pressure, tightness, heaviness, burning, and other negative sensations. Assessments were made at baseline (pre-treatment), immediately post-treatment, and Day 1 post-treatment. No formal hypothesis testing was pre-specified for this endpoint.

Corneal staining was assessed by the examiner using the National Eye Institute corneal grading scale and a slit-lamp. Each of the 5 corneal regions (superior, inferior, central, temporal, & central), was graded on a 0-3 scale, where 0=normal-no staining (best); 1=mild-superficial stippling micropunctate staining; 2=moderate-macropunctate staining with some coalescent areas; and 3=severe-numerous coalescent macropunctate areas and/or patches (worst). The scores were summed for each eye, and an overall corneal staining score was computed as the average of the sum from both eyes. Overall scores ranged between 0-15, with higher change value indicating greater damage to the corneal surface. Assessments were made at baseline (pre-treatment), immediately post-treatment, and Day 1 post-treatment. No formal hypothesis testing was pre-specified for this endpoint.

IOP (fluid pressure inside the eye) was measured by Goldmann applanation tonometry. A higher IOP can be a greater risk for developing glaucoma or glaucoma progression (leading to optic nerve damage). A negative change value indicates an improvement. No formal hypothesis testing was pre-specified for this endpoint.

Visual acuity was assessed with spectacles or other visual corrective devices in place using Early Treatment Diabetic Retinopathy Study (ETDRS) charts. Results are presented in logarithm of the minimum angle of resolution (logMAR) with 0.2 in logMAR corresponding to 10 ETDRS letters read. A lower logMAR change value indicates an improvement in visual acuity. No formal hypothesis testing was pre-specified for this endpoint.