Meibomian gland dysfunction (MGD) is one of the most common causes of dry eye diseases. Over the past decade, several treatment options in MGD have been extensively studied including warm compression, lid hygiene, ocular lubricants, forceful expression, LipiFlow thermal pulsation system, intraductal probing, debridement scaling and intense pulsed light (IPL). IPL is a broad spectrum, non-coherent and polychromatic light source with a wavelength spectrum of 500-1200 nm. It can be filtered to allow only a range of wavelengths to be emitted. Different wavelength makes different depth of tissue to absorb a specific light energy. Intense pulsed light (IPL) has been widely used in dermatology as a therapeutic tool for removal of hypertrichosis, benign cavernous hemangioma, benign venous malformations, telangiectasia, port-wine stain and pigmented lesions. Concurrent ocular surface improvements have been observed in patients undergone IPL treatment. Very few prospective clinical trials showed that subjective dry eye symptoms decreased and some of the dry eye signs also improved. Nonetheless, there is still inconsistency in the efficacy of IPL among these studies. Biomarkers, specifically cytokines, in dry eye diseases have been studied to some extent. Moreover, the change in ocular surface inflammatory cytokines in patients with MGD after IPL treatment is unclear.

The investigators proposed a prospective randomized double-masked sham-controlled clinical trial to investigate the efficacy and safety of intense pulse light in MGD patients.

Inclusion Criteria:

1. Able to read, understand and sign an informed consent form
2. 18-80 years of age
3. Fitzpatrick skin type 1-5
4. Able and willing to comply with the treatment /follow-up schedule and requirements
5. Presence of meibomian gland on each lower eyelid's meibography
6. Current diagnosis of stage1-4 of MGD in both eyes, according to the International Workshop on Meibomian Gland Dysfunction: Report of the Subcommittee on Management and Treatment of Meibomian Gland Dysfunction

Exclusion Criteria:

1. Contact lens wearer within the past 1 month and throughout the study
2. Recent ocular surgery or eyelid surgery within the past 6 months
3. Neuro-paralysis in the planned treatment area within the past 6 months
4. Current use of punctual plugs
5. Pre-cancerous lesions, skin cancer or pigmented lesions in the planned treatment area
6. Uncontrolled infections or uncontrolled immunosuppressive diseases
7. Subjects who have undergone refractive surgery within the past 6 months
8. Diseases in the planned treatment area that could be stimulated by light at 560 nm to 1200 nm (e.g.,Herpes simplex 1 and 2, Systemic Lupus Erythematosus, porphyria)
9. Use of photosensitive medications and/or herbs that may cause sensitivity to 560-1200 nm light exposure, such as isotretinoin, tetracycline, or St. John's Wort
10. Pregnancy and lactation
11. Radiation therapy to the head or neck within the past year, or planned radiation therapy throughout study period
12. Treatment with chemotherapeutic agent within the past 8 weeks, or planned chemotherapy throughout study period
13. Any condition revealed during the eligibility screening process whereby the physician deems the subject inappropriate for this study
14. Declared legally blind in one eye
15. IPL treatment within the past 12 months
16. Lipiflow treatment, or any equivalent treatments, within the past 12 months
17. Any anti-glaucomatous eye drop uses within the past 3 months and throughout the study period