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100 Cards in this Set
- Front
- Back
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What are the symptoms of tear disfunction? |
• Dry eye: - foreign body sensation - gritty eye, “sand in eye” - photophobia
• Wet eye: - excessive tearing - itching - soreness of skin beneath eye (secondary to epiphora) - Staining |
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What worsens the symptoms of dry eye? |
Enviromental factors: • wind • low humidity • pollution/smoke • cold conditions |
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What is a dry eye disease? |
• A heterogeneous group of conditions resulting in inadequate lubrication of the ocular surface.
• All produce symptoms of ocular surface ‘dryness’ and discomfort. |
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Give a definition of eye dry eye. |
Definition: dry eye is a disorder of the tear film due to tear deficiency or excessive tear evaporation which causes damage to the interpalpebral ocular surface and is associated with symptoms of ocular discomfort.
(NEI/Industry Workshop on Clinical Trials in Dry eyes, 1995) |
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What are the classifications of dry eye disease? |
1 Tear deficient dry eye 2 Evaporative dry eye |
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What is Tear deficient dry eye? |
A Sjøgren’s Syndrome (SS) B non-Sjøgren Syndrome |
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What is Evaporative dry eye? |
A oil deficient B lid related C surface change D contact lens-related |
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How is Sjøgren’s Syndrome (SS) classified? |
1) primary 2) secondary |
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How is non-Sjøgren’s Syndrome classified? |
1) lacrimal disease 2) lacrimal obstruction 3) reflex hyposecretion |
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How is Evaporative dry eye classified as? |
A) oil deficient 1 primary 2 secondary B) lid related e.g. blink disorders C) surface change E.g. xerophalmia (vitamin A deficiency) D contact lens-related |
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What is Sjøgren’s Syndrome? |
An autoimmune disorder consisting of dry eye (KCS) and dry mouth (xerostomia), which often involves nasal and vaginal mucous membranes also. |
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What systemuc diseases is Sjøgren’s Syndrome associated with? |
rheumatoid arthritis
systemic lupus erythematosus |
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What are the two types of Primary Sjøgren’s Syndrome? |
• with systemic immune dysfunction but no connective tissue disease.
• with no systemic immune dysfunction and no connective tissue disease. |
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What is Secondary Sjøgren’s Syndrome? |
In addition to dry eye and dry mouth, secondary SS patients also have a defined connective tissue disease, most commonly rheumatoid arthritis or systemic lupus erythematosus |
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What other autoimmune diseases less commonly seen with secondary Sjøgren’s Syndrome? |
• progressive systemic sclerosis • Hashimoto’s thyroiditis • polymyositis • polyarteritis nodosa • Waldenström’s macroglobulinemia |
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What is the prevalence of Sjøgren’s Syndrome? |
<0.6% |
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At what age can you get Sjøgren’s Syndrome? |
age 22-70 years average 43 years |
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Who is most likey to get Sjøgren’s Syndrome? |
gender: F:M = 9:1 |
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What can ocular drying cause? |
• Corneal scarring with loss of vision • Ulceration • Infection and perforation |
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What are the causes of Sjøgren’s Syndrome? |
• inflammation of the lacrimal and salivary glands
• blood changes typical of autoimmune disease
• high levels of cytokines in the conjunctiva and tears- damage corneal and conjunctival epithelium |
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What is the Non-Sjøgren Syndrome lacrimal disease? |
Two types: Primary Secondary |
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What is the Non-Sjøgren Syndrome primary lacrimal disease? |
• congenital absence of gland • acquired primary lacrimal disease |
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What is the Non-Sjøgren Syndrome secondary lacrimal disease? |
• sarcoidosis • vitamin A deficiency (xerophthalmia) • HIV |
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What are the Non-Sjøgren Syndrome Lacrimal obstruction diseases? |
• Trachoma • Cicatricial pemphigoid • Stevens-Johnson Syndrome • Chemical burns |
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What are the Non-Sjøgren Syndrome Reflex hyposecretion diseases? |
• Neuroparalytic keratitis • Long-term rigid contact lens wear • Seventh nerve palsy (e.g. Bell’s palsy) |
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What is Stevens-Johnson Syndrome? |
Acute, severe mucocutaneous disease |
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What are the causes of Stevens-Johnson Syndrome? |
hypersensitivity reaction to: • drugs • mycoplasma pneumoniae • herpes simplex virus • Epstein-Barr virus, enteroviruses |
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Who are more susceptible? |
Males 2:1 |
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What are the eye signs of Stevens-Johnson Syndrome? |
• papillary conjunctivitis • dry eye • epiphora following lacrimal drainage obstruction |
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What medicines cause tear dysfunction? |
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Name the oil deficient dry eye disease. |
1) primary • absence of Meibomian glands • distichiasis (M glands produce lashes) 2) secondary • anterior and posterior marginal blepharitis • obstructive Meibomian gland disease |
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What is Hyperthyroidism |
• over-active thyroid gland • swelling of extraocular muscles • proptosis • inadequate globe coverage by eyelids, incomplete blink • chronic corneal desiccation |
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What enviromental factors cause dry eye? |
• VDU use - Reduced blink rate • air-conditioned offices and cars - Reduced humidity
• Pollution- increase in tear debris (ocular irritation) • reflex lacrimation (?epiphora) |
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What eye surgery can cause dry eye? |
Lasik The main proposed cause is corneal nerve damage. LASIK disrupts both the dense sub-basal nerve plexus and stromal corneal nerves. Glands don't know to produce tears. |
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What is Acquired primary lacrimal disease? |
• Commonest cause of tear deficient dry eye. • Histology shows infiltration by inflammatory cells, loss of normal structure, atrophy and fibrosis. |
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What glands are involved with Acquired primary lacrimal disease? |
Only Lacrimal glands |
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How do you examine and investigate a dry eye px? |
• History • Non-invasive break-up time • Assessment of tear meniscus • Fluorescein staining and invasive break-up time • Schirmer/phenol thread test • Rose Bengal |
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How would you take history for a dry eye px? |
• Questionnaires • Common symptoms suggestive of dry eye include: sandy, gritty feeling, soreness or scratchiness • Severity of symptoms frequently do not correlate with the severity of signs. |
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What are dry eye symptoms? |
• Discomfort (soreness, irritation, foreign body sensation) • Blurred vision |
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What are dry eye signs? |
• Reduced tear meniscus • Reduced tear BUT • Corneal and conjunctival staining within palpebral perture (particularly inferiorly) |
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What is the prevalence of dry eye? |
The condition is estimated to affect 15–33% of people aged over 65 years, and is about 50% more common in women than men |
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What happens to the tear meniscus with a dry eye? |
• The tear meniscus is reduced in aqueous deficiency dry eye. • Indicated by reduced height and radius of curvature |
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How do you assess tear stabilty? |
Tear break up time. • Invasive and non-invasive methods • Varies between individuals and in the same individual at different times of day. |
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With the TBUT, what would suggest an unstable tear film? |
• A BUT of <10seconds is indicative of an unstable film |
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How is fluorescein used to assess dry eye? |
• Demonstrates epithelial damage • Should be used in conjunction with a yellow barrier filter |
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What part of the eye is staining more common? |
• In dry eye staining more common inferiorly with nasal more pronounced than temporal |
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What is Rose Bengal? |
• Use in conjunction with local anaesthetic to limit stinging • Stains dead or degenerate cells |
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What is lissamine green? |
• Stains dead or degenerate cells • As an alternative to rose bengal for assessing the ocular surface • Unlike rose bengal which causes ocular irritation |
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With Keratoconjunctivitis sicca, where would you expect to see staining? |
• bulbar conjunctiva stains first • temporal and inferior cornea stain as disease progresses |
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With Mild dry eye/exposure, where would you see staining? |
• superficial band of horizontal punctate staining (fluorescein) |
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With Bacterial keratoconjunctivitis, where would you see staining? |
diffuse punctate staining |
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How do you measure tear secretion? |
• Phenol red thread test • Schirmer test |
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Explain the phenol-red thread test. |
• Cotton thread impregnated with phenol red: a pH sensitive dye. • Changes from yellow to red on contact with the tears. • Wetted length of thread measured after 15 secs.
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Where measurement with the phenol-red thread test would indicate dry eye? |
< 6mm is diagnostic of dry eye |
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Explain the Schirmer test. |
Schirmer test used without anaesthetic assesses reflex tear secretion to conjunctival stimulation. |
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Where measurement with the Schirmer test would indicate tear deficiency? |
Less than 6mm of wetting after 5 minutes. |
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What is the tear lab? |
The TearLab osmolarity system is a device that measures the osmolarity of tears and is used to diagnose and monitor dry eye disease |
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How do you manage tear dysfunction? |
• Increasing tear volume and ocular lubrication using artificial tear substitutes. • Reducing rate of tear fluid loss from conjunctival sac - Rate of lacrimal drainage - Evaporation • Improvement of tear quality/consistency. • Improvement of lacrimal drainage in cases of epiphora. |
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What is the management for dry eyes? |
• Lubricants • Tear preservation • Lid hygiene • Oral antibiotics • Immunosuppresants • Alternative therapies |
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How would you treat intermittent dry eye symptoms? |
Artificial tears |
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How would you treat midrange dry eye? |
Artificial tears Punctal occlusion |
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What is the treatment for Severe dry eye? |
Pharmacological surgery. |
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What are Ocular lubricants? |
Drops, gels and ointments are used to treat the discomfort associated with conditions in which the tear film is reduced or unstable. |
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What else can ocular lubricants used for? |
Prevent exposure keratitis in patients undergoing surgery, in intensive care, in ectropion or other abnormalities of the eyelids where part of the ocular surface is exposed |
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What are the limitations of using ocular lubricants to treat dry eye? |
• Formulation cannot replace complexity of natural tears
• The presence of preservatives in artificial tears can compromise the ocular surface following prolonged use.
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What preservative is incompatible with contact lenses? |
Benzalkonium chloride is incompatable with soft contact lens wear. |
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What are the requirements of artificial tear substitutes? |
• Non-irritant • Good ocular lubricating effect • Long retention time within conjunctival sac • Not interfere with optical performance |
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What is the formulation of artificial tear substitutes? |
• pH 7.4 (slightly alkaline) • Tonicity 0.9% sodium chloride • Viscolizing agent- substitute for mucin • Preservative- protect opened preparation from bacterial colonisation |
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Name some Viscolizers. |
• Cellulose derivatives • Polyvinyl alcohol (PVA) • Polyvinylpyrroline • Hyaluronic acid • Polyacrylic acid (Carbomer 980) |
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What are Cellulose derivatives? |
• methylcellulose • carboxymethylcellulose • Hydroxyethylcellulose- Minims Artificial Tears • hydroxypropylmethylcellulose (hypromellose)- Tears Naturale |
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What is Hyaluronic acid? |
• Originally used as a visco-elastic substance during ocular surgery • cataract extraction • vitrectomy
• 0.2% concentration shown to have greater retention time compared to other viscolizers |
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What is Polyacrylic acid (Carbomer 980) used in? |
Gels • Liquefaction of gel on blinking; reconstitution of gel after blinking
• increased retention time in eye (7x greater than PVA).
• number of daily applications of tear substitute reduced (20 to 4)
• improved protection during sleep |
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Name some preservatives in artificial tear substitutes? |
• Benzalkonium chloride • Cetrimide (0.01%) Viscotears • Chlorbutamol - irritation a problem |
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Name some unpreserved options for artificial tears. |
Single use applicators • Blink, Systane etc…….. Unpreserved multidose (Micro filters) • Hyco San original, plus and Extra • Hyabak • Can be used for 6/12 |
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What increses retention time of artificial tears? |
Viscosity -highly viscous preparations remain in the conjunctival sac longer than low viscosity preparations |
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What is the downside to high viscous tears? |
Reduces VAs Better to use at night |
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Name the artificial tear groups. |
• Hydroxypropyl methylcellulose (HPMC) Hypermellose • Cellulose • Polyvinyl alcohol (PVA) • Liquid Polyols • Hyaluronic acid • Inserts • Miscellaneous |
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How would you reduce rate of tear outflow? |
Punctal occlusion |
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How do you reduce rate of tear evaporation? |
Alter environment • Use of room humidifiers • Reduction in room temperature • Reduction in palpebral aperture area • surgical; small lateral tarsorrhaphy (stich lids together) • Everest-Harris spectacles • side-shields reduce evaporative effect of wind |
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What are some alternative dry eye therapies? |
• Omega-3 and omega-6 fatty acids • Hot compress • Lipiflow |
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What is Blepharitis? |
Blepharitis is inflammation or infection of the eyelid margins. |
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Name some anterior Blepharitis |
• Staphylococcal • Seborrhoeic |
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Name some posterior Blepharitis |
• Meibomianitis • Meibomian seborrhoea |
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What are the symptoms of Blepharitis? |
• Ocular irritation (burning, FB sensation if MK) • Blurred vision if associated with Tear Film instability • Watery eye |
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What are the signs of Blepharitis? |
• Crusting around lashes • Lid hyperaemia • Loss of lashes • Staining of inferior cornea • Abnormal Meibomian secretions • TF instability & debris; greasy scales (seborrhoea) or collarettes (staphylococcal) at lash roots |
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What is staphylococcal anterior blepharitis? |
Colonization of the eyelids by staphylococci leads to formation of fibrinous scales and crust around the eyelashes. |
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What is anterior seborrheic blepheritis? |
Characterized by dandruff-like skin changes around the base of the eyelids, resulting in greasy scales around the eyelashes. |
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What would you see with Staphylococcal blepharitis? |
• Hard scales and crusting the base of the lashes. • chronic conjunctival hyperemia, mild papillary changes. • scarring and notching (tylosis) of the lid margin , trichiasis (misdirected eyelashes), madarosis (loss of lashes) or poliosis (loss of pigmentation of lashes). |
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What secondary changes would you see with Staphylococcal blepharitis? |
• stye formation • marginal keratitis phlyctenulosis (Corneal lesions near the limbus and then spread to cornea) |
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What would you see with Seborrheic Blepharitis? |
• Hyperemic and greasy anterior lid margin with sticking together of lashes.
• the scales are located any where on the lid margin and lashes. |
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What is the treatment for blepheritis? |
• Lid hygiene • Antibiotics *Topical *Oral • Weak topical steroids • Tear substitutes |
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What lid hygiene treatments would you use for blepheritis? |
• warm compresses applied for several minutes to soften crusts at the bases of the lashes.
• Lid scrubbing of the lid margins once or twice daily with a cotton bud dipped in a dilute solution of baby shampoo(???? or NaHCO3).
• Commercially pads for lids scrubs. |
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What is Demodex Mite? |
• Often associated with blepharitis • Ectoparasite • Lash follicles • Too small to be seen with the slit-lamp? |
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What are the symptoms of Demodex Mite? |
• Ocular discomfort • Burning • Itching • Soreness • Mild photophobia? • Symptoms of dry eyes • Blurred vision • Contact lens intolerance |
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What are some signs of Demodex Mite? |
• lid margin hyperaemia • cylindrical dandruff’: characteristic clear sleeve (collarette) covers base of lash • persistent infestation of the lash follicles may lead to misalignment, trichiasis or madarosis. |
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What is the management for Demodex Mite? |
• Weekly lid scrub with • tea tree oil by • experienced practitioner • Toxic to cornea • Artificial tears |
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What is posterior blepheritis? |
• more common condition 24% v 12% • inflammation of the inner eyelid • level of the meibomian glands • MEIBOMIAN GLAND DYSFUNCTION |
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What is meibomian gland dysfunction? |
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What other ocular conditions can be associated with meibomian gland dysfunction? |
• Chalazion-Which maybe multiple and recurrent. • Tear film instability and dry eye
• Epithelial basement membrane defects
• Cutaneous- acne rosacea - Seborrhoeic dermatitis - Acne vulgaris
• Contact lens intolerance |
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What is the treatment for meibomian gland dysfunction? |
• Heat! • Massaging the eyelids. • Swabbing the margin |
