Vectored Thermal Pulsation, Intense Pulsed Light, and Eyelid Warm Compress (VIEW) Therapies for Meibomian Gland Dysfunction- a Randomized, Assessor-masked, Active-controlled Clinical Trial

Dry eye disease (DED) is an emerging, under-recognized and under-treated epidemic of the 21st century. It is one of the commonest reasons seeking eye consultation worldwide. Depending on the diagnostic criteria, geographic location and population concerned, prevalence of DED ranges from 30 to over 50% in the Asia Pacific regions compared to around 5-10% in the United States. Up to 90% of DED is closely associated with meibomian gland dysfunction (MGD), a chronic and progressive condition characterized by terminal duct obstruction, qualitative and/or quantitative changes in the glandular secretions (meibum) which causes tear instability by increasing tear evaporation and subsequently increased tear osmolarity, ocular surface inflammation, epithelial damage and ocular surface disease. Studies suggest that MGD affects between 5-20 % of Caucasians and over 60% of Asians populations.

Conventional treatments for MGD including self-administered eyelid hygiene, eyelid warm compress therapy (EW), artificial tears, including lipid-containing lubricants are limited in their efficacies for moderate to advanced disease. Prescription medications (topical steroids, topical and oral antibiotics, topical immunomodulatory agents e.g. cyclosporine and oral omega-3 essential fatty acids) have demonstrated efficacies in improving symptoms and signs of MGD; however side-effects including preservative-related adverse events, development of antibiotic resistance, cost, accessibility, off-label use, and the need for ongoing treatments often limit their long-term use.

Despite the described range of available options, management for MGDs is often considered unsatisfactory and frustrating by clinicians and patients. Compliance to long-term, home-based self-administered therapies is known to be suboptimal while practitioner-administered treatment including meibomian gland expression (MGX) provides transient relief.

Intense pulsed light (IPL) therapy is widely used in cosmetic dermatology as well as therapeutically for a wide range of skin conditions with favourable efficacy and tolerability. Concurrent MGD improvements were observed serendipitously in patients undergoing IPL for rosacea. With growing interest in combining IPL+MGX as practitioner-administered physical therapy for MGD, recent review and meta-analysis showed its effectiveness and safety while calling to investigate its effect beyond 6 months after the last IPL treatment.

Vectored thermal pulsation (VTP) is approved by FDA as another practitioner-administered physical therapy for MGD. The device covers both the cutaneous and mucosal surfaces of the eyelids; the rear portion of the device provides heat to the MG, and the front portion gives mechanical stimulation to the eyelid skin. It evacuates the MG of the upper and lower eyelids simultaneously with minimal discomfort while protecting the cornea, rendering the experience for patients generally favorable. Recent meta-analysis showed that a single 12-minute VTP was more efficacious than EW in treating MGD.