Change in Ocular Surface Disease Index (OSDI)
The Ocular Surface Disease Index (OSDI) is a 12-item symptom frequency-based questionnaire. It is self-administered to assess DED-related symptoms and severity.
The final OSDI score is calculated by dividing the product of the total sum of the score and 25 by the total number of answered questions, with a range from 0 to 100. The score reflects the severity of DED: normal: 0-12, mild: 13-22, moderate: 23-32, severe: >33).
Change in symptom Assessment iN Dry Eye (SANDE, modified)
Symptom Assessment iN Dry Eye (SANDE) questionnaire is a 2-item frequency- and severity-based visual analog scale. It is self-administered to evaluate the frequency and severity of dry eye symptoms.
The final SANDE score is calculated by obtaining the square root of the product of the frequency of symptoms score and the severity of symptoms score, with a range from 0 (minimal degree of dry eye symptoms) to 100 (maximal degree of dry eye symptoms)
Change in 36-Item Short Form Health Survey (SF-36)
The 36-Item Short Form Health Survey (SF-36) is a 36-item self-administered questionnaire, with 8 domains included: physical functioning (PF), role physical (RP), bodily pain (BP), general health (GH), vitality (VT), social functioning (SF), role emotional (RE), and mental health (MH). The physical health sub-scale and Mental health sub-scale will be graded respectively.
Change in the Work Productivity and Activity Impairment Questionnaire: General Health V2.0 (WPAI:GH)
The Work Productivity and Activity Impairment Questionnaire: General Health V2.0 (WPAI: GH) is a 6-item questionnaire that measures impairments in work and activities.
Change in Non-Invasive Tear Break Up Times (NIBUT)
Non-Invasive tear break up time (NIBUT) will be measured by the OCULUS Keratograph® 5M (Oculus, Wetzlar, Germany) in both eyes. Participants were instructed to keep their eyes on as much as possible during the examination. First and average NIKBUTs will be recorded by the machine.
Shortening NIBUT(< 10 seconds) suggests instability of the tear film.
Changes in Tear Meniscus Height (TMH)
The tear meniscus height (TMH) will be measured by the OCULUS Keratograph® 5M (Oculus, Wetzlar, Germany).
Changes in Bulbar Redness
Bulbar conjunctival hyperaemia is automatically evaluated the Keratograph 5M (OCULUS, Wetzlar, Germany) according to the JENVIS grading scale from 0 to 4.
Changes in Lipid Layer Thickness
The lipid layer thickness (LLT) of the tear film will be determined with the LipiView ® II Ocular Surface Interferometer (TearScience, Morrisville, NC). Minimum, Maximum, and Average thickness in nanometers (nm) will be measured.
Changes in Partial Blinking Rate
The partial blinking rate will be reported as the percentage of incomplete blinks. The total and partial blinking times will be automatically recorded by the LipiView ® II Ocular Surface Interferometer (TearScience, Morrisville, NC).
Changes in Meiboscore
The meiboscore grading will be based on the infrared meibography captured by the LipiView ® II Ocular Surface Interferometer (TearScience, Morrisville, NC). Both superior and inferior eyelids will be recorded. The result will be graded by a masked assessor.
The grading scheme is a 3-point scale (grade 0, no meibomian gland atrophy; grade 1, less than 1/3 area of glands lost; grade 2, 1/3-2/3 area of glands lost; grade 3, more than 2/3 area of glands lost)
Change in Tear Film Breakup Time (TBUT)
The tear film breakup time (TBUT) is the time of the initial breakup of the tear film after a full blink. 2% Sodium fluorescein will be instilled in both eyes of the subjects. A masked follow-up assessor will do the examination via the slit lamp with a blue cobalt light. The TBUT will be measured three times with a stopwatch and taken on average.
Change in Corneal and Conjunctival Fluorescein Staining
Fluorescein sodium liquid will be instilled on the ocular surface. After 3 minutes, the corneal and conjunctival punctate epithelial erosions will be observed and graded via the slit lamp biomicroscope with a blue cobalt light.
The Oxford Grading System is selected for grading. The severity will be divided into 6 grades (Grade 0, absent; Grade 1, minimal; Grade 2, mild; Grade 3, moderate; Grade 4, marked; Grade 5, severe)
Change in Expressibility of Meibomian Glands in the Meibomian Glands Yielding Liquid Secretion (MGYLS) (the inferior eyelid)
Expressibility of the inferior eyelid meibomian glands is assessed with the Meibomian Gland Evaluator (TearScience, North Carolina, USA) applied inferior to central aspects of the inferior eyelid margin. The result is graded by a masked assessor.
The meibomian glands yielding liquid secretion (MGYLS) is the total number of glands that yield lipid secretions at the central aspects of the eyelid margin.
Change in Quality of Expressed Meibum
The meibomian gland evaluator will be applied to the central aspects of the inferior eyelid margin. The result will be graded by a masked assessor.
Each gland in each area will be assessed for expressibility and graded according to a 4-point scale: grade 0, no secretion; grade 1, inspissated/ toothpaste-like expression; grade 2, cloudy fluid secretion; and grade 3, clear fluid/normal secretion. The sum scores of 5 glands will be between 0 and 15.
Change in Lid Margin and Eyelash Abnormalities
Lid margin and eyelash abnormalities will be accessed by a slit lamp, including telangiectasia, meibomian gland capping, Demodex lash cylindrical collarettes, staphylococcal lash crusting, and seborrheic lash crusting.
All items will be graded based on a four-point scale: grade 0, absent; grade 1, mild; grade 2, moderate; grade 3, severe.
Change in Tear Film Osmolarity (TFO)
The tear film osmolarity (TFO) is measured by the ScoutPro™ Osmolarity System (TearLab , San Diego, CA) via the disposable test card in both eyes.
The normal osmolarity was considered as lower than 308 mOsm/L in both eyes. A difference more than 8 mOsm/L between two eyes reflects the stability of the tear film.
Changes in Schirmer I test
The Schirmer I test (ST) will be performed by sterile standard filter paper strips without anesthesia. The filter paper strips will be gently put on the temporal side of both lower eyelids for 5 minutes. The wetting length by tears in each strip will be recorded in nanometers (mm) by a masked assessor.
The strips will be collected in sterile centrifuge tubes respectively for further laboratory tests.
Changes in Matrix metallopeptidase 9 (MMP-9)
The MMP-9 enzyme-linked immunosorbent assay (ELISA) development kit (Invitrogen, Carlsbad, CA)) will be applied for measurement of the concentration of MMP-9 in participants' tears.
Adverse events (AEs)
The adverse events (AEs) will be the number of incidents based on a checklist of symptoms, signs, and diseases by patients' reporting, slit-lamp examination, or doctor's diagnosis.