Advanced Diagnosis and Management of OSD and Tear Dysfunction Arthur B. Epstein, OD, FAAO Phoenix, Eye Care & The Dry Eye Center of Arizona Phoenix, AZ, USA Our understanding of the ocular surface has evolved dramatically over the past few years. Growing interest in dry eye and tear dysfunction has increased interest in this practice segment. We apply an evidence-based approach with extensive use of video animation, to integrate novel concepts into a unified perspective of the ocular surface environment with direct practical and clinical diagnostic and therapeutic application. Current therapy is reviewed with specific focus on dogma vs. newer concepts and clinical approaches that contrast traditional palliative therapies to newer approaches that target root causes and functional issues. Course Outline I. Overview of the current theories of ocular surface and tear layer a. Current thinking on surface anatomy and physiology i. The structure of the ocular surface ii. Interaction with the tear components b. Support for primary functions of the tear structure c. Balance and homeostasis of the ocular environment II. Historical perspective and evolution of knowledge a. Previous theories i. Sjögren (1940) - Identified and defined keratoconjunctivitis sicca ii. Wolff (1946): Tri-layer tear film iii. Holly & Lemp (1973): Expanded understanding of mucin b. Contemporary thinking i. Scheffer C.G. Tseng (1997): Surface and tear film interaction 1. The preocular tear film and the ocular surface function as a unit 2. The external adnexa maintains tear film stability 3. Intact innervation is critical to ocular surface health a. Corneal epithelial limbal stem cells play a critical role 4. The underlying basement membrane and stromal fibroblasts support surface health and function ii. Donald Korb (1980 & 2002-Present): MGD, Role of lipids & Lid Wiper Epitheliopathy iii. David Meadows (2004): Tear film memory & biochemical complexity of the tear film iv. Kelly Nichols MGD Workshop (2011) MGD and EDE
III. Anatomy and Physiology of the Ocular Surface a. Ocular surface adaptations that support tear function i. Surface tear interaction b. The importance of surface area and surface morphology i. Role of microvilli and glycocalix 1. Transforming hydrophobic to hydrophilic 2. Structural aspects of the tears c. Tear components and structure i. Adhesive qualities of mucins 1. Trans-membrane mucins ii. Viscoelastic properties of the tears 1. Cohesion and regularity a. Tear film memory 2. Cushioning a. Fluid mechanics of the tear i. Newtonian vs. non-newtonian fluids b. Surface protection and regularity d. Lubricity and barrier function i. The critical importance of lipids to tear film function 1. Oil and water don t mix 2. Lipid serves as an evaporative and functional barrier 3. Lipid layer complexities a. Non-polar lipids b. Phospholipids i. Bind the lipid layer to underlying gel forming mucins e. The lids are a source of energy and motion IV. The tear film exists as a complex interwoven system a. Balance is an essential requirement for maintenance of the ocular surface i. Disturbance to one element can affect all of the others ii. The normal ocular surface is stable iii. The body seeks to restore a normal state V. The critical importance of tear stability a. The elements of stability b. Disruptors of stability VI. Contact lenses and the ocular environment a. How contact lenses promote surface drying b. Insight into the contact lens surface and relationship to the ocular environment c. Silicone hydrogel and lipid depletion VII. Surface disease diagnostic testing a. Tear film and OSD testing i. Surface staining patterns ii. Break-up time 1. Etiology a. Inside out vs. outside in? iii. Osmolarity
iv. Lipid layer & MG testing 1. Interferometry 2. Expression a. MGE b. Mastrota paddle 3. Meibography v. Break up time FBUT NIBUT 1. Automated - Oculus Keratograph 5M vi. Other testing VIII. Surface Disorder Pathophysiology a. Etiology i. Tear dysfunction 1. Evaporative dry eye relative importance 2. Aqueous deficiency a. Evaporative b. Secretion issues i. Systemic vs. local disease 3. Tear stagnation 4. Punctal stenosis 5. Conjunctival chalasis ii. Inflammation iii. Staph and other microbial disease related to DES iv. Neurotrophic disease v. Surface disruption 1. Staining 2. Loss of normal morphology vi. Lid abnormalities and disorders 1. Decreased or ineffective blinking 2. Excessive blinking 3. Anatomical/functional problems of the lid vii. Delayed Tear Clearance viii. Surface abnormality 1. Conjunctival chalasis ix. LWE x. Meibomian gland dysfunction 1. Among the most prevalent of all ocular disease a. Evaporative component in 87% of all dry eye patients 2. Progressive 3. Inflammatory cascade locally and within ocular surface environment IX. Diagnosis a. Conventional approaches i. Subjective 1. Questionnaires and Surveys a. OSDI b. SPEED
ii. Meibomian gland evaluation 1. Diagnostic expression 2. Korb MGE 3. Transillumination iii. Staining 1. Fluorescein 2. Rose Bengal 3. Lissamine Green iv. FTFBUT v. Schirmer testing vi. Tear prism assessment vii. Examination of lid gap 1. Bells phenomenon b. Advanced Technology i. Lipiview ii. Keratograph K5M 1. Meibography 2. NIBUT iii. TearLab Osmolarity iv. RPS Inflmadry X. Etiology Based Treatment a. Management of MGD i. IPL ii. Probing iii. Lipiflow iv. MiBo Theroflow v. Conventional therapy 1. Technique 2. Compliance 3. Cautions b. Palliative (mostly OTC but different approaches for different etiologies) i. Balanced approaches ii. Normalization of osmolarity iii. Other strategies c. Restorative i. Mucomimetics ii. Secretagogues iii. Lipid supplementation iv. Tear retention strategies 1. Punctal Plugs 2. Cautery v. Amniotic membrane lenses and grafts vi. Bandage lenses vii. PROSE and Scleral lenses viii. Surgical approaches d. Anti-inflammatory i. Cyclosporine ii. Steroids
iii. Emerging medications Arthur Epstein is a consultant for Alcon Laboratories, B+L, BioD, BioTissue, NovaBay, Oculus, PRN Pro Omega Health, Science Based Health, Shire, TearLab and Vistakon.