Dry eye

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Dry eye

  1. 2. Fatemeh Dashti Optometrist . BSc - MSc
  2. 3. Dry eye <ul><li>Dry eye is a disease of the ocular surface attributable to different disturbances of the natural function and protective mechanisms of the external eye, leading to an unstable tear film during the open eye state. </li></ul>
  3. 4. Lacrimal system
  4. 5. Pre-corneal tear film <ul><li>-Superficial thin lipid layer </li></ul><ul><li>-Middle bulk aqueous layer </li></ul><ul><li>-Innermost mucous layer </li></ul>
  5. 6. Lipid layer <ul><li>Lipid layer is secreted by the meibomian glands & gland of Zeiss. </li></ul><ul><li>Their function is: </li></ul><ul><li>To reduce the evaporation of the aqueous layer. </li></ul><ul><li>To increase the surface tention& asist in vertical stability of the tear film </li></ul><ul><li>To lubricate the eyelids. </li></ul>
  6. 7. Aqueous layer <ul><li>The middle layer is secreted by lacrimal gland & has following functions: </li></ul><ul><li>To supply atmospheric oxygen to the avascular corneal epithelium </li></ul><ul><li>Anti –bacterail function </li></ul><ul><li>To reduce the irregularities of anterior corneal surface </li></ul><ul><li>To clean away the debris. </li></ul>
  7. 8. Mucin layer <ul><li>The inner layer is secreted by the conjunctiva goblet cells, crypts of Henle & glands of Manz . </li></ul><ul><li>It converts the corneal </li></ul><ul><li>epithelium from hydrophobic </li></ul><ul><li>to hydrophilic state. </li></ul>
  8. 11. Normal tear film <ul><li>Volume : 7-10 μ l , avoid blinking 20-30 μ l </li></ul><ul><li>Thickness : 7microns </li></ul><ul><li>Production : 1.2 μ l/min (0.5-2.2) </li></ul><ul><li>Turn over : 16% </li></ul><ul><li>Tear evaporation (0.14 μl/min in 30% humidity) </li></ul><ul><li>pH : 6.5-7.6 </li></ul><ul><li>Surface tension : 40.7 dyne/cm </li></ul><ul><li>Refractive index : 1.336 </li></ul><ul><li>Osmolarity : 300-310 mOsm/l </li></ul>
  9. 12. Chemical properties of normal tear film <ul><li>1- general tear composition </li></ul><ul><li>2- electrolytes </li></ul>Water 98.2 g/100ml Solids(total) 1.8 g/100ml Ash 1.05 g/100ml Sodium 120-170 mmol/l Potassium 26-42 mmol/l Calcium 0.3-2.0 mmol/l Magnesium 0.5-1.1 mmol/l Chloride 120-135 mmol/l Bicarbonate 26 mmol/l
  10. 13. Chemical properties of normal tear film <ul><li>3-Anitproteinasis </li></ul><ul><li>4-Nitrogenous substances </li></ul>α 1-Anti trypsin 0.1-3.0 mg% α 1-anti Chymotrypsin 1.4 mg% Inter α trypsin inhibitor 0.5 mg% α 2 Macroglobulin 3-6 mg% Total protein 0.668-0.800 g/1ooml Albumin 0.392 g/100ml Globulin 0.2758 g/100ml Uric acid 0.005 g/100ml Urea 0.04 mg/100ml Total nitrogen 158 mg/100ml Nonprotein nitrogen 51 mg/100ml
  11. 14. Chemical properties of normal tear film <ul><li>5- glucose : 2.5 mg/100ml </li></ul><ul><li>6- sterols : Cholestrol & cholestrol esters 8-32 mg/1ooml </li></ul><ul><li>7- Miscellaneous </li></ul>Citric acid 0.6 mg/100ml Ascorbic acid 0.14 mg/100ml Lysozyme 1-2 mg/ml Amino acid 7.58 mg/100ml Lactate 1-5mmol/l Prostaglandin 75 pg PF/ml Catecholamine 0.5-1.5 µg/ml
  12. 15. Healthy tears <ul><li>A complex mixture of proteins, mucin, and electrolytes </li></ul><ul><ul><li>Antimicrobial proteins: Lysozyme, lactoferrin </li></ul></ul><ul><ul><li>Growth factors & suppressors of inflammation: EGF, IL-1RA </li></ul></ul><ul><ul><li>Soluble mucin 5AC secreted by goblet cells for viscosity </li></ul></ul><ul><ul><li>Electrolytes for proper osmolarity </li></ul></ul>
  13. 16. Tears in chronic dry eye <ul><li>Decrease in many proteins </li></ul><ul><li>Decreased growth factor concentrations </li></ul><ul><li>Altered cytokine balance promotes inflammation </li></ul><ul><li>Soluble mucin 5AC greatly decreased </li></ul><ul><ul><li>Due to goblet cell loss </li></ul></ul><ul><ul><li>Impacts viscosity of tear film </li></ul></ul><ul><li>Proteases activated </li></ul><ul><li>Increased electrolytes </li></ul>
  14. 17. Dry eye clasification
  15. 18. Tear deficient dry eye
  16. 19. Evaporative dry eye
  17. 20. Dry eye classification
  18. 21. Classification scheme for dry eye proposed by NEI/industry workshop
  19. 22. Dry eye <ul><li>Dry eye to afflict more than 7 million Americans </li></ul><ul><li>over the age of 40. </li></ul><ul><li>Risk factors: </li></ul><ul><li>– Older age </li></ul><ul><li>– Female sex </li></ul><ul><li>– Postmenopausal status </li></ul><ul><li>– Previous LASIK </li></ul>
  20. 23. aging <ul><li>The most common cause of severe dry eye is aging. Aging is directly associated with a reduction in lipid production, resulting in evaporative dry eye. </li></ul><ul><li>Over time your body produces less oil- 60% less at age 65 than at age 18. </li></ul><ul><li>The incidence of severe dry eyes over the age of 65 is around 75%. </li></ul>
  21. 25. Most susceptible group to dry eye <ul><li>Post menopausal women </li></ul><ul><li>Patient of 50 yrs plus group </li></ul><ul><li>Patient on diuretics , beta blockers , psychotropics & oral acne medication </li></ul><ul><li>Rheumatoid arthritis patient </li></ul><ul><li>People exposed to heat and dust </li></ul><ul><li>Patient with blepharitis (MGD) </li></ul><ul><li>Environmental Stresses </li></ul><ul><ul><li>Contact Lens Wear </li></ul></ul><ul><ul><li>Wind </li></ul></ul><ul><ul><li>Air Pollution </li></ul></ul><ul><ul><li>Low Humidity: Heating/Air Cond. </li></ul></ul><ul><ul><li>Lack of Sleep </li></ul></ul><ul><ul><li>Use of Computer Terminals </li></ul></ul>
  22. 26. Medications That May Contribute to Dry Eye Disease <ul><li>Systemic </li></ul><ul><li>Topical </li></ul><ul><ul><li>Antihypertensives </li></ul></ul><ul><ul><li>Antiandrogens </li></ul></ul><ul><ul><li>Anticholinergics </li></ul></ul><ul><ul><li>Antidepressants </li></ul></ul><ul><ul><li>Cardiac Antiarrhythmic Drugs </li></ul></ul><ul><ul><li>Parkinson’s Disease Agents </li></ul></ul><ul><ul><li>Antihistamines </li></ul></ul><ul><ul><li>Preservatives in tears </li></ul></ul>
  23. 27. Symptoms of Ocular Surface Disease Current Triggers of Dry Eye Disease Environment Medications Contact Lens Surgery Rheumatoid Arthritis Lupus Sjögren’s Graft vs Host Postmenopause Meibomian Gland Disease Inflammation Tear Deficiency/ Instability Irritation
  24. 30. Common symptoms <ul><li>– ocular discomfort </li></ul><ul><li>– irritation such as scratchiness, grittiness, foreign body sensation, burning, blurring, and itching </li></ul><ul><li>Correlations between symptoms, clinical signs, and diagnostic test results are variable </li></ul>
  25. 31. symptoms
  26. 33. Dry eye <ul><li>Our understanding of dry eye has evolved from </li></ul><ul><li>considering: </li></ul><ul><li>Tear volume insufficiency </li></ul><ul><li>to </li></ul><ul><li>Tear film instability with underlying </li></ul><ul><li>inflammation due to altered tear composition </li></ul>
  27. 38. Propose mechanism of ocular surface inflammation in dry eye
  28. 40. Dry eye : History <ul><li>Exacerbation by certain activities (reading or </li></ul><ul><li>watching TV, or environment (low humidity or </li></ul><ul><li>smoky) </li></ul><ul><li>patients With dry eye tend to get worse at night , </li></ul><ul><li>while patients with predominantly MGD are worse </li></ul><ul><li>in the morning </li></ul><ul><li>Symptomatic response to artificial tears support the </li></ul><ul><li>diagnosis of dry eye </li></ul>
  29. 41. Dry eye : history <ul><li>Past ocular history : </li></ul><ul><li>contact lens, allergy, herpes infection, corneal </li></ul><ul><li>surgery, topical medications </li></ul><ul><li>Past medical history : </li></ul><ul><li>autoimmune disease, diabetes, neurological disease </li></ul><ul><li>Medications: </li></ul><ul><li>Complete list of the patient’s medications </li></ul>
  30. 42. Dry eye diagnostic tests Type of evaluation Test Tear secretion Schirmer I,John”s test, cotton thred test, Dye clearance test, Fluorophotometery Tear stability Invasive BUT- NoninvasiveBUT Tear film integrity Epithelial integrity Rose bengal staining Physical feature Osmolality , PH, Ferning evaporation rate Chemistry Electrolytes, Protein(lysozyme, lactoferin) Histology Imperssion cytology, lacrimal gland biopsy, minor salivary gland biopsy
  31. 43. Entery level tests for dry eye <ul><li>Tear break – up time (TBUT) </li></ul><ul><li>Fluorescein clearance test </li></ul><ul><li>Tear film osmolarity </li></ul>
  32. 44. Tear break up- time test
  33. 45. Tear break up- time test <ul><li>Indicate of tear film insatiability in all different causes of dry eye </li></ul><ul><li>With fluorescein (invasive) –reflex tearing </li></ul><ul><li>Non invasive (toposcope) </li></ul><ul><li>Values of < 10s are considered abnormal </li></ul><ul><li>Values of 5-9s are borderline dry eye </li></ul><ul><li>Values of < 5s are clearly indicative of </li></ul><ul><li>dry eye </li></ul>
  34. 47. NITBUT
  35. 48. NITBUT
  36. 49. Fluorescein clearance test (FCT) <ul><li>Delayed clearance of tears from the eye is thought to be a contributing factor in pathogenisis of dry eye </li></ul><ul><li>Tear turn over is important for: </li></ul><ul><li>removing inflammatory cytokines </li></ul><ul><li>providing fresh supply of growth factors </li></ul><ul><li>Delay tear clearance strongly correlates with ocular irritation symptoms independent of aqueous tear production </li></ul>
  37. 50. Fluorescein clearance test (FCT) <ul><li>Standardized amount of fluorescein is placed in cojunctival sac and tear turn over rate is determined by persistent of fluorescein in tears at specific timepoints later </li></ul><ul><li>To detect amount of residual fluorescein is using Schirmer </li></ul><ul><li>strip to collect fluorescein –stained tears. </li></ul><ul><li>Fluorophotometer : quantify amount of fluorescein persisting in eye </li></ul><ul><li>– Minimally stimulated tear samples collected </li></ul><ul><li>– using micro tube from Inferior tear meniscus 15 minute </li></ul><ul><li>after 5μl of 2% fluorescein </li></ul>
  38. 51. Fluorescein clearance test (FCT)
  39. 52. Tear film osmolarity <ul><li>In dry eye tear film is in a hyperosmolar state: </li></ul><ul><li>Decrease production </li></ul><ul><li>Decrease volume </li></ul><ul><li>Decrease lipid </li></ul><ul><li>Decrease stability </li></ul><ul><li>Increase evaporation </li></ul>
  40. 53. Tear film osmolarity Lacrimal gland disease Decreased corneal sensation Increased palpebral fissure Meibomian gland dysfunction Decreasde sensation Increased evaporation Increased tear osmolarity
  41. 54. Tear film osmolarity <ul><li>Values higher than 312 mOsol / Liter are diagnostic of dry eye: </li></ul><ul><li>– 90% sensitivity </li></ul><ul><li>– 95% specificity </li></ul><ul><li>A commercial osmometer specifically designed to test nanometer volume of tear is now in use but is not widespread due to cost consideration </li></ul>
  42. 55. Normal osmolarity : 300-310 mosm/l
  43. 56. Tear film osmolarity Condition Expected range of value Normal < 312 mosm/l Borderline dry eye 312- 323 mosm/l Moderate/severe dry eye > 323 mosm/l
  44. 57. Secondary tests to determine the specific causes of the dry eye <ul><li>Schirmer test </li></ul><ul><li>Diagnostic dye staining </li></ul><ul><li>Nasolacrimal reflex </li></ul><ul><li>Serum auto antibodies </li></ul><ul><li>Meibomian gland evaluation </li></ul><ul><li>Impression cytology </li></ul><ul><li>Conjunctiva and cornea sensation </li></ul><ul><li>Tear protein analysis </li></ul>
  45. 58. Schirmer test
  46. 59. Schirmer test <ul><li>The most commonly used technique for assessment of tear secretion described in 1903 (aqueous production) </li></ul><ul><li>In patients with dry eye there is not a strong correlation between the level of aqueous tear production and the severity of dry eye </li></ul>
  47. 60. Schirmer test <ul><li>The Schirmer strip is placed over the lateral third of the lower lid </li></ul><ul><li>If using an anesthetic , adequate time should be given after the drop to minimize reflex tearing from the burning sensation due to drop. </li></ul>
  48. 61. <ul><li>Schirmer I (without anesthesia ) : basic and reflex secretion </li></ul><ul><li>Schirmer II (with anesthesia ): basic secretion </li></ul><ul><li>A cut of 10 mm to indicate aqueous tear deficiency </li></ul><ul><li>Schirmer I test in 5 mm of wetting after 5 min </li></ul><ul><li>– very specificity (90%) </li></ul><ul><li>– 25% sensitive for diagnosis dry eye </li></ul>
  49. 62. Schirmer test <ul><li><5mm wetting in 5 min is sign of clinical dry eye </li></ul><ul><li>5-10mm wetting suggests borderline dry eye </li></ul><ul><li>>10mm wetting represents normal secretion </li></ul>
  50. 63. Phenol red test
  51. 64. Diagnosting dye stainings <ul><li>The installation of dyes is a common method to detect ocular surface epithelial pathology </li></ul><ul><li>associated by dry eye: </li></ul><ul><li>– Fluorescein sodium </li></ul><ul><li>– Rose bengal </li></ul><ul><li>– lissamine green </li></ul>
  52. 65. Diagnosting dye staining <ul><li>Fluorescein is the most commonly used : </li></ul><ul><li>– stains the cornea more than conjunctiva </li></ul><ul><li>– significantly greater amount of staining in Sjogren’s aqueous tear deficiency </li></ul>
  53. 66. Diagnosting dye staining <ul><li>Rose bengal unlike fluorescein which stains tissue by penetrating into intercellular spaces stains: </li></ul><ul><li>– devitalized epithelial cell </li></ul><ul><li>– healthy epithelial cells when they are not protected by a healthy layer of mucin. </li></ul>
  54. 67. Rose bengal staining <ul><li>In interpretation of rose bengal staining in dry eye is based on two factors :(Van Bijsterveld score) </li></ul><ul><li>– intensity and location </li></ul><ul><li>– scale of 0 – 3 in 3 area </li></ul><ul><li>Conjunctiva usually stains more intensity than the cornea </li></ul><ul><li>The intensity of rose bengal staining correlates well with the degree of aqueous tear deficiency </li></ul>
  55. 68. Diagnosting dye staining <ul><li>Lissamine green B similarly stains with rose bengal: </li></ul><ul><li>– produces much less irritation </li></ul><ul><li>– staining pattern to be identical to rose bengal </li></ul><ul><li>– When score >5 indicated diagnosis of Sjogren’s syndrome </li></ul>
  56. 69. Diagnosting dye staining <ul><li>Rose bengal staining </li></ul><ul><li>Inferior epitheliopathy </li></ul>
  57. 70. Nasolacrimal reflex <ul><li>Can be elicited by stimulating the nasal mucosa under the middle turbinate with a cotton – tipped applicator: </li></ul><ul><li>– increase tearing dramatically in non-Sjogren’s syndrome </li></ul><ul><li>– no increase in Sjogren’s syndrome </li></ul>
  58. 71. Serum auto antibodies <ul><li>Its criteria used to diagnosis of Sjogren’s syndrome </li></ul><ul><li>Presence one or more these auto antibodies: </li></ul><ul><li>– ANA (titer≥ 1:160) </li></ul><ul><li>– RF (titer≥ 1:160) </li></ul><ul><li>– anti – Ro (ss-A) or anti – La (ss-B) </li></ul><ul><li>presence of anti – M3 muscarian cholinergic receptor anti body in a high percentage of Sjogren’s syndrome </li></ul>
  59. 72. Meibomian gland evaluation <ul><li>Diagnosis is made by following pathologic signs: </li></ul><ul><li>– ductal orifice metaplasia (white shafts of keratin in the orifices) </li></ul><ul><li>– increase turbidity and viscosity of the expressed secretions </li></ul><ul><li>– reduced expressibility of secretion </li></ul><ul><li>– morphologic abnormality of the gland acine and ductules </li></ul>
  60. 73. Meibomian gland evaluation-NORMAL
  61. 74. Meibomian gland evaluation-MGD
  62. 75. Impression cytology <ul><li>In advanced dry eye the epithelium undergoes pathology changes: </li></ul><ul><li>– squamous metaplasia </li></ul><ul><li>– decreased density of goblet cells </li></ul><ul><li>a small piece of nitrocellulose membrane applied against the conjunctival surface </li></ul><ul><li>Methods to grade the extent and severity of squamous metaplasia based on : </li></ul><ul><li>- Loss of goblet cells </li></ul><ul><li>-Enlargement and increase cytoplasmic / nuclear ratio </li></ul><ul><li>-Keratinization </li></ul><ul><li>Overall impression cytology is a highly sensitive method </li></ul>
  63. 77. Conjunctiva and cornea sensation <ul><li>Decreased corneal sensation can be both the cause and the effect of dry eye </li></ul><ul><li>Sensory denervation may lead to dry eye by : </li></ul><ul><li>-Decreasing the afferent signal that drive aqueous tear secretion </li></ul><ul><li>-Reducing the blink rate (leading to ocular surface desiccation) </li></ul><ul><li>-Altering growth and differentiation of ocular surface epithelium through diminished trophic influence of trigeminal nerve </li></ul><ul><li>-Auto immune sensory neuropathy and sensory neural degeneration due to inflammation or chronic over stimulation </li></ul>
  64. 78. Corneal esthesiometry
  65. 79. Tear proteins analysis <ul><li>Lysozyme accounts for 20-40% of total tear protein: </li></ul><ul><li>– its measurement is based on the enzyme ability to lyse a suspension of the bacterium , micrococcus lysodeikticus </li></ul><ul><li>– Tear lysozyme level are decreased in ATD </li></ul><ul><li>– more sensitive test than either the Schirmer test or rose bengal staining </li></ul><ul><li>– main disadvantage is lack of specifity </li></ul><ul><li>– false positive in HSV keratitis , bacterial conjunctivitis , smog irritation and malnutrition </li></ul>
  66. 80. Tear protein analysis <ul><li>Lactoferrin is normally produced by the lacrimal gland and used as a relative indicator of lacrimal gland function, measured by lacto card. </li></ul><ul><li>Epithermal growth factor to be lower in tears with Sjogren’s syndrome and there is inverse correlation with severity of dry eye. </li></ul>
  67. 81. VALUES IN NORMAL TEAR AND DRY EYE
  68. 82. INTERFEROMETRY OF THE LIPID LAYER
  69. 83. Tearscope –plus lipid layer thickness(LLT)
  70. 84. Tearscope –plus lipid layer thickness(LLT) <ul><li>Five main categories of normal lipid appearance are graded in order of increasing thickness and visibility: </li></ul><ul><li>Open meshwork </li></ul><ul><li>Tight meshwork </li></ul><ul><li>Waves </li></ul><ul><li>Amorphous </li></ul><ul><li>Colors </li></ul><ul><li>The abnormal appearances of tle lipid layer are: </li></ul><ul><li>Globular </li></ul><ul><li>Abnormal colors </li></ul><ul><li>Lipid break-up </li></ul>
  71. 85. Tearscope –plus lipid layer thickness(LLT) <ul><li>Waves </li></ul><ul><li>Colors </li></ul>
  72. 86. CRYSTALLIZATION : FERNING TEST <ul><li>Tear film composition affects the way in which a coolected sample dries on a glass slide. This test is based on mucus ferning patterns that have been used in cervical smear testing. Tears are collected with a glass capillary & placed on a glass slide & left to dry at room temperature. The sample is then observed in white light or by polarized microscopy & classified in to 4 grades according its appearance following crystallization. </li></ul><ul><li>The tears of dry eye patient exibit less ferning than those of normal patients. </li></ul><ul><li>Test may reflect the quality of tear protein profile. </li></ul>
  73. 87. Ferning test
  74. 88. Levels of severity of dry eye disease
  75. 89. Treatment
  76. 90. treatment <ul><li>Dry eye /ocular surface disorder is : </li></ul><ul><li>progressive , life-long ,inflam mator y , symptomatic disease. </li></ul><ul><li>Treatment must aim for : </li></ul><ul><li>*explanation of disease & psychotherapy </li></ul><ul><li>*prevention of aggregative factors. </li></ul><ul><li>*treatment of the cause (inflammation). </li></ul><ul><li>*stimulation of tear secretion . </li></ul><ul><li>*Replacement of tear . </li></ul><ul><li>*Maintenance of tear . </li></ul><ul><li>*treatment of ocular surface disorders. </li></ul><ul><li>present treatments are only palliative , Although Dry eye isn’t curable, But new trials are against the causes. </li></ul>
  77. 91. prevention of aggregative factors <ul><li>A: medications ( Atropines ,anti- histaminic, , Beta-blockers , contra- septives ,diuretics, Retinoid , chemotherapy , - anti-glaucoma, preservatives) </li></ul><ul><li>B: environment (low humidity – dust –smoke – allergens-cosmetics)(≠ air conditioners - +humidifiers ) </li></ul><ul><li>C: long periods of near work (computer -…) – overnight jobs </li></ul><ul><li>D: viral inf. , allergy . </li></ul><ul><li>E : pregnancy – Hormone replace therapy </li></ul><ul><li>F: C.L. </li></ul><ul><li>G: some ocular surgeries (refractive surgery – blepharoplasty keratoplasty - ECCE ) </li></ul>
  78. 92. Dry Eye : lubricants:Replacement of tear <ul><li>Artificial tear (drops -gel – pomade –spray –inserts-…) </li></ul><ul><li>Indications of use : </li></ul><ul><li>A) symptomatic relief of dry eye. </li></ul><ul><li>B) symptomatic relief of irritants (wind – sun -….) </li></ul><ul><li>C) symptomatic relief of exposure . </li></ul><ul><li>D) refreshment of contact lenses & prosthesis. </li></ul><ul><li>E) as basis for preparing topical medications . ( e.g. ; fort antibiotic drop) </li></ul>
  79. 93. Artificial Tear Eye drops <ul><li>Solvent water </li></ul><ul><li>Active ingredient water soluble polymers </li></ul><ul><li>Viscosity polymers concentration </li></ul><ul><li>Preservatives prevention of contamination </li></ul><ul><li>balanced tonicity Inorganic electrolytes </li></ul><ul><li>NaCl&KCL equivalent to 0.9% NaCl </li></ul><ul><li>P.H buffers </li></ul><ul><li>Anti-oxidants Sometimes Vit. A </li></ul><ul><li>Lipids phospholipids </li></ul>
  80. 94. Artificial Tear Eye drops <ul><li>Active ingredient ( water soluble polymers) </li></ul><ul><li>provides viscosity & tear film stability </li></ul><ul><li>Hyaloronic acid </li></ul><ul><li>Cellulose & methylcellulose & their derivatives: </li></ul><ul><li>hydroxypropyl Cellulose </li></ul><ul><li>hydroxyethyl Cellulose </li></ul><ul><li>hydroxypropyl methylcellulose (HPMC) 0.2% & 0.3% & 0.5% </li></ul><ul><li>carboxymethylcellulose 0.25% & 0.5% & 1% Carmelosa (low viscosity) </li></ul><ul><li>Polyvinyl alcohol 1.4% </li></ul><ul><li>Povidine 0.6% </li></ul><ul><li>Glycerin 0.3% & 1% </li></ul><ul><li>dextran 70 </li></ul><ul><li>propylene glycol (PG) </li></ul><ul><li>polyEthyleneGlycol (PEG 400) </li></ul><ul><li>polycarophil </li></ul><ul><li>hydroxypropyl Agar (Systane R) </li></ul>
  81. 95. Artificial Tear Eye drops <ul><li>Mechanisms of effect : </li></ul><ul><li>classical view of the tear film : a 10-micron film of aqueous tears, sandwiched between thin layers of lipid and mucous.mucous promoting tear adherence. lipid preventing evaporation & This it has been challenged recently that : </li></ul><ul><li>1) the tear film may be considerably thicker than 10 microns ,& </li></ul><ul><li>2) dissolved mucus and protein may form a structured aqueous gel that adheres to the epithelium and covers its irregularities, thus providing a high-quality optical surface </li></ul><ul><li>Artificial tear provides a viscous layer which : </li></ul><ul><li>Stabilize & thicken pre-corneal tear film . </li></ul><ul><li>prolongs tear film B.U.T. </li></ul><ul><li>keeps ocular surface wet & lubricated . </li></ul><ul><li>helps to repair ocular surface damage </li></ul><ul><li>keeps ocular surface smooth(improves decreased vision & aberrations) </li></ul>
  82. 96. Artificial Tear Eye drops <ul><li>Due to temporary effect of these drugs, </li></ul><ul><li>Consider for other long term therapeutic options </li></ul>
  83. 97. Artificial Tear Eye drops <ul><li>Preservatives : </li></ul><ul><li>Benzalkanium chloride (0.01% for eye-drops , 0/02% for C.L. solutions & 1% as disinfectant ) </li></ul><ul><li>Chlorbutanol . </li></ul><ul><li>Chlorhexidine (0.002- 0.005%) </li></ul><ul><li>Thimerosal & mercuric oxides (0.002- 0.005% ) </li></ul><ul><li>EDTA . </li></ul><ul><li>Methylparaben . </li></ul><ul><li>Propylparaben . </li></ul><ul><li>Polyquad ( SPK) </li></ul><ul><li>Purite . </li></ul><ul><li>Potasium sorbate . </li></ul><ul><li>Sodium perborate (air touch changes to H2O2,then H2O & O2) </li></ul><ul><li>Sorbic acid ( less toxic ) </li></ul>
  84. 98. Ocular complications of Preservatives <ul><li>pigmentation: (mercury deposits in lids –conj. – cornea & lens ) </li></ul><ul><li>Irritation: (redness – photophobia – lacrimation –burning -….) dermatitis & urticaria & eczema – blepharitis – </li></ul><ul><li>allergic: papillary & follicular conjunctivitis –pseudo membrane pemphigoid – symblepharon- SPK – corneal edema – panus –corneal opacity – adherence to CL. & CL. intolerance – ocular surface mal-function & inflammation </li></ul><ul><li>Toxic: Epith. Cell exfoliation . SPK </li></ul><ul><li>Due to side effects of preservatives , now preservative – free artificial tears are made , but most of them are in unit dose form (chance of contamination),Also they are expensive. </li></ul>
  85. 99. Preservative – free artificial tears
  86. 100. Artificial Tear Eye drops <ul><li>Dosage & frequency of use : </li></ul><ul><li>As frequent as needed </li></ul><ul><li>Q 15min ~ occasionally if necessary </li></ul><ul><li>Some believe & advise for a scheduled regimen : (e.g. Q 6h ) </li></ul>
  87. 101. Artificial Tear Eye drops <ul><li>Storage : </li></ul><ul><li>Keep out of the reach of children. </li></ul><ul><li>Don’t keep outdated medicine . </li></ul><ul><li>keep away from direct light & air ( air-tight bottles) </li></ul><ul><li>keep between 8` ~ 35` (room temperature) </li></ul><ul><li>(no need for refrigerator ) [Store away from heat (>40`)] </li></ul><ul><li>care for bottle head contamination ( ≠ hand touch ) (close immediately after use ) </li></ul><ul><li>after opening ,use in a maximum period of 15 -30 days ! </li></ul>
  88. 102. Gel tears <ul><li>Less greasy than pomades </li></ul>
  89. 103. Emollients : simple Eye pomades <ul><li>Base : Lanolin , Petrolatum , mineral oil , Also electrolytes ,usually no preservatives . </li></ul><ul><li>They form an oily layer on ocular surface Which disseminates by blinking . </li></ul><ul><li>They remain longer than drops . </li></ul><ul><li>They are used for : </li></ul><ul><li>Sever dry eye </li></ul><ul><li>Exposure keratopathy </li></ul><ul><li>Night time use in dry eye </li></ul><ul><li>Use 0.25 -0.50 inch /fornix . </li></ul><ul><li>It causes slight irritation & temporary blurred vision . </li></ul><ul><li>Don`t use it with C.L. & Don`t Use pomades before eye drops . </li></ul>
  90. 104. Emollients : simple Eye pomades
  91. 105. slow release lubricants : [Lacrisert] <ul><li>each rod contains 5mg hydroxypropyl cellulose (It is preservative free ) </li></ul><ul><li>It imbibes water , swells ,dissolves. </li></ul><ul><li>effect begins after 1 h & remains for 14–24 h {So 1 insert / morning is enough for 1 day} </li></ul><ul><li>It is inserted in lower fornix .[ education is necessary (either by doctor or written directory of drug package)] </li></ul>
  92. 106. Disadvantages : <ul><li>More expensive .(~ 55 US$ / box = 1US $ / day) </li></ul><ul><li>Manual dexterity is needed . </li></ul><ul><li>Sometimes blurred vision due to thick tear film (use BSS or physiologic serum) </li></ul><ul><li>Dislocation into palpebral fissure & irritation (even loss) </li></ul><ul><li>Complications as : eye redness or discomfort ; watering of eyes .photophobia; matting or stickiness of eyelashes; swelling of eyelids. </li></ul>
  93. 107. artificial tear spray Less chance of contamination . Tears Again Liposome spray (10cc) ($15) ( occusoft) Natures Tears Eye Mist (10cc) ($7) (all scripts)
  94. 108. Dry Eye : stimulation of tear secretion <ul><li>Secretagugoes (cholinergic agonists & Muscarinic ) purinergic receptor (p2y2) agonist [Diquafosal (Inspire)] </li></ul><ul><li>stimulates mucin &tear secretion of Goblet cells. </li></ul><ul><li>Oral Pilocarpine (Salagan) ( effective for dry mouth not dry eye- 5mg tab x 4-6/day) </li></ul><ul><li>IBMX (isobutyl-methyl xanthin) </li></ul><ul><li>Eledoisin (endekapeptides) </li></ul>
  95. 109. Dry Eye : treatment of the cause <ul><li>A) MGD – allergy </li></ul><ul><li>B) Lagophthalmos & exposure </li></ul><ul><li>C) ocular surface disorders, proptosis ,retraction ,Ectropion ,trichiasis ,pterigium. </li></ul><ul><li>D) inflammation : </li></ul><ul><li>systemic treatment of rheumatoid & other causes of Sjogren’s synd, topical anti- inflammatory drugs : </li></ul><ul><li>recent clinical trials demonstrated effectiveness of topical Cyclosporin A 0.05% </li></ul>
  96. 110. Dry Eye : surgical treatment <ul><li>Usually when medications doesn’t alleviate symptoms. </li></ul><ul><li>Prevention of tear drainage (surgical Punctal occlusion) </li></ul><ul><li>Prevention of tear evaporation (Tarsorhaphy & cantorhaphy) </li></ul><ul><li>Transplantation of secretory glands </li></ul>
  97. 111. Dry Eye : maintenance of tear <ul><li>Temporary (absorbable collagen inj. & plugs –Gelatin ) ( N-buthyl cyanoacrylate up to 2.5 w) </li></ul><ul><li>Reversible (Silicon – acrylamide & smart plug) </li></ul><ul><li>Permanent (thermal & electro-cautery –laser ) ( conj. Graft) </li></ul><ul><li>Usually at first ,temporary collagen plugs of only lower punctom;If suitable then permanent plugs. </li></ul><ul><li>If there is reflex tearing ,only lower punctom, otherwise both punctoms. </li></ul><ul><li>If still inadequate ,then cantorhaphy. </li></ul>
  98. 112. collagen discs & plugs
  99. 113. Silicon plugs <ul><li>Complications: </li></ul><ul><li>Irritation ( erosions -GPC –allergic dermatitis – symblepharon -..) </li></ul><ul><li>Pyogenic granoloma </li></ul><ul><li>Adherence of bacteria to plug & infection </li></ul><ul><li>Extrusion </li></ul><ul><li>Migration into canaliculs (canaliculitis – dacryocystitis) </li></ul>
  100. 114. Smart plugs (thermo-sensitive acrylic) <ul><li>Best performance under : </li></ul><ul><li>Slit lamp examination (Magnification & illumination) </li></ul><ul><li>Cold light </li></ul><ul><li>Topical anesthesia </li></ul><ul><li>Needs a punctom dilator & forceps </li></ul>
  101. 115. Permanent Punctal occlusion <ul><li>In mild cases can cause epiphorea , in sever KCS has no effect (there is no tear ) </li></ul><ul><li>so it’s contra-indicated if : </li></ul><ul><li>Schirmer >10mm </li></ul><ul><li>Normal cornea </li></ul><ul><li>Temporary conditions </li></ul>
  102. 116. Tarsorhaphy & cantorhaphy <ul><li>Usually when corneal abnormality </li></ul>
  103. 117. Transplantation of secretory glands
  104. 118. Dry eye treatment recommendations by severity level
  105. 119. Dry eye treatment recommendations by severity level
  106. 120. Dry eye treatment recommendations by severity level
  107. 121. Dry eye treatment recommendations by severity level
  108. 122. Never walk on the traveled path, because it only leads you where the others have been. Graham Bell

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