Therapeutic Efficacy and Safety of Non-Invasive RF Treatment in Refractory MGD

Inclusion Criteria: 1. Age 18 or more 2. Bilateral dry eye disease as confirmed by presence of both symptoms and signs 2.1 Symptoms: Abnormal result on the Standard Patient Evaluation of Eye Dryness Questionnaire (SPEED) dry eye symptom questionnaire (≥5) 2.2 Signs: Abnormal result in at least one of the following three clinical tests - tear osmolarity, NIKBUT and corneal staining for punctate epithelial erosions and, 3. Bilateral moderate to severe meibomian gland dysfunction - at least Grade 1 meibum quality (cloudy appearance) and Grade 2 meibum expressibility (moderate pressure required). And, 4. Refractory MGD - The failure to respond to at least three types of conventional therapy, including artificial tears, topical or systemic antibiotics and anti-inflammatory treatments and the aforementioned heat-based therapies, over a period of at least 2 years 5. Fitzpatrick skin type I-IV - Type V and VI skinned subjects are excluded from the study due to the high risk of pain and focal hypopigmentation 6. Mentally fit to give informed consent Exclusion Criteria: 1. Fitzpatrick skin type V-VI 2. History of eyelid scarring 3. Infrared meibography evidence of significant acinar gland atrophy (dropout of \>30%) - these patients have been shown not to benefit from heat-based therapies due to end-stage disease 4. Pregnancy or lactation 5. Active corneal disease such as infectious keratitis, allergic keratoconjunctivitis, pterygium, exposure keratopathy, lagophthalmos, trichiasis or dellen 6. Current systemic intake of photosensitive medications, including tetracycline group of drugs. 7. History of corneal abnormality or surgery within 3 months