Ocular Surface Disease

Dry eye

Multifactorial symptomatic disease of the ocular surface characterized by loss of homeostasis of the tear film

Accompanied by tear film instability and hyperosmolarity, inflammation and damage, and neuro-sensory abnormalities]

CANNOT be cured → Tx to improve symptoms

Dry eye pathophysiology

Hyperosmolarity and inflammation, increase in salts and proteins in tears but not enough tears to counteract

• Epithelial damage and damage to glycocalyx and goblet cells

• Increase friction when blinking

Neuro-sensory abnormalities with dry eye

Neuropathic pain: Pain sensation in absence of stimuli

Experience of symptoms may be worse than what signs pt presents with

Dry eye epidemiology

• Menopausal and postmenopausal females

• Sjogrens and rosacea

• Antihistamines, decongestants, HRT

• CL, LASIK, cataract surgery

Dry eye classifications

Primary: Aqueous deficient, Evaporative (MGD), Mixed

Special: Sjogrens (autoimmune)

Dry eye signs with lids and meibomian glands

• Anterior/posterior bleph

• Demodex

• Meibomian glands will express and then go dormant for a few hours

Dry eye signs with the ocular surface

• Conj hyperemia: Often at 9 and 3 positions, can be inferior with lagophthalmos

• PEE

Mechanical signs of dry eye

• Lid wiper epitheliopathy

• Filamentary keratitis

Lid wiper epitheliopathy

Pathognomonic

Portion of the upper lid becomes damaged or inflamed from increased friction and poor lubrication

Filamentary keratitis

Tiny strands or large plaques of mucus that stick to cornea in areas of epithelial loss from loss of aqueous portion (cannot wash out)

Result of increase mucin production, decreased tear production, and formation of epithelial defects

Use thick artificial tears and mechanically remove debris

Symptom screenings for dry eye

• SPEED questionnaire

• Ocular Surface Disease Index Questionnaire

Higher scores = Worse dry eye

SPEED Questionnaire

Standard Patient Evaluation of Eye Dryness

4 question test that assesses frequency and severity of dryness over current day, 72 hours, and 3 months prior

Do not define number score

Ocular Surface Disease Index 12

12 questions that assess ocular symptoms, vision related task difficulty, and discomfort from environment

Ocular Surface Disease Index 6

6 questions to reduce pt burden and make scoring easier for clinician

Slit lamp evaluation for dry eye

• Lid evaluation

• Tear film

• Cornea and conj

Targeted testing for dry eye

• Tear quantity

• Tear stability

• Vital dye staining

• Meibomian gland function

• Advanced testing

Schirmer test

Tear quantity test

Measures tear production, normal is 10mm or greater in 5 minutes

Aqueous deficient → Reduced Schirmer test

Tear Break Up Test (TBUT)

Tear stability test

Measures stability of tear film, fluorescein used, normal TBUT is 10 seconds

Test ends after 10 seconds, pt blinks, or tear film thins

Evaporative deficiency

Tear meniscus

Tear stability test

Small curved pool of tears that rests along edges of upper/lower lids, normal is .3mm

Aqueous deficiency

Fluorescein

Vital dye staining test

Assess areas of epithelial loss, appears bright green with cobalt blue filter

Normal should be clear/smooth, PEEs will be highlighted

Lissamine green

Vital dye staining

Highlights mucus or dead/degenerating cells, helps to visualize inflammation

Appears green with white light

More staining = More inflammation

Meibography

Meibomian gland function test

Imaging technique to visualize meibomian glands of upper and lower lids, quality and quantity of glands

Pts with dry eye will have truncation (shorter) and meibomian gland loss

Do meibomian glands grow back?

No

Advanced testing for dry eye

• Tear osmolarity

• InflammaDry

• Interferometry

Tear osmolarity

Advanced test

Measures amount of solute to amount of water in tears

Water decreases while solute starts the same → Pulls water from cornea and harms epithelium

Normal is under 308 mOsms/L, higher number results in corneal involvment

InflammaDry

Advanced test

Detects MMP-9 in tears

MMP-9

Inflammatory marker produced by inflamed epithelial cells

Only present in ocular surface disease

Positive vs negative InflammaDry results

Positive has 2 vertical lines (red and blue)

Negative has 1 vertical blue line

Invalid will have no lines

Interferometry

Advanced test

Measures lipid layer thickness through iridescent color and blink pattern

Thinned in dry eye, only done if meibomian glands look normal

Dry eye foundational therapy

Patient education, chronic disease with no cure

Evaluate aspects of life that may make dry eye worse

Environmental changes for dry eye

• Avoid prolonged near tasks (20/20/20 rule)

• Avoid dry environments (humidifier)

• Physical protection (scleral CL or chamber goggles)

Targeted therapy

Tx that targets a specific mechanism

• Lid and meibomian glands

• Inflammation

• Tear deficiency

Targeted therapy for lid and meibomian glands

• Lid hygiene

• Meibomian gland debridement

• Warm compress

• Thermal pulsation

• IPL

• LLLT

Lid hygiene

Removes excess oil, bacteria, and debris from lid minimum once a day

Wipes or foam

Meibomian gland debridement

Removal of debris and keratinized cells from lid margin to promote meibum

Warm compress

Melts hardened oils, achieve lid temp of 104 for 10-15 mintues

Bruder mask, rechargeable, washcloth

Thermal pulsation

Applies hear to glands along with pressure to express gland blockages, treatment done every 9-12 months

Lipiflow

Intense Pulse Light (IPL)

Broad spectrum light to penetrate deeper layers of skin with wavelengths of 500-1200nm

Can decrease demodex, bacterial load, and improve meibum consistency

Used for evaporative dry eye

Low Level Light Therapy (LLLT)

Low power red light to improve meibum consistency and for anti-inflammatory properties

Better than IPL because directly applied to eyelids and can be used on all skin types

Targeted therapy for inflammation

Fight inflammatory markers

• Topical steroids

• Topical immunomodulators (cyclosporine)

• LFA-1 (Lifitegrast)

Targeted therapy for tear deficiency

• Artificial tears

• Neurostimulation of trigeminal

• Punctal plugs

Artificial tears

Supplement pt natural tears and are classified for type of dry eye

Aqueous deficient - Watery

Evaporative deficient - Cloudy

Combination tears are a mix of both

Trigeminal nerve activation

Activate trigeminal to produce more tears

Tyrvaya: Intranasal varenicline

Tryptyr: Acoltremon ophthalmic solution, burns significantly

Punctal plugs

Placed into tear duct to block drainage

Temporary (collagen) or semi-permanent (silicon)

Advanced Tx

For pts who have no success with conventional

• Autologous serum

• Secretagogues

• Amniotic membrane

Autologous serum

Topical drops made from pt’s blood, donor blood, or umbilical cord

Contains neurotropic growth factor, epidermal growth factor, vit A, fibronectin, and lysozymes to improve tear film stability

Secretagogues

Increase mucin production, not approved in US

Oral pilocarpine secretagogues used in severe dry eye or Sjrogens

Amniotic membrane

Donated placental tissue used to promote corneal healing

Rich in collagen, growth factors, and anti-inflammatory proteins

Cryopreserved or dehydrated

Additional Tx for dry eye

• Omega fatty acids: Reduce inflammation

• Vitamin B12: Reduce inflammation and increase tear stability

• Vitamin A: Improves symptoms and signs but can be detrimental to meibomian gland health