AED - Superficial Corneal Diseases - Week 9 Flashcards
How thick is the cornea centrally? Give a range.
490-560 microns
How many cells thick is the corneal epithelium? What does this prevent the diffusion of?
6-8 cells thick
Prevents diffusion of fluorescein
What layer of the cornea is significant in recurrent corneal erosion?
Basement membrane
Consider trauma to Bowman’s layer of the cornea. Does it regenerate?
No regeneration following trauma
What happens to Descemet’s membrane during oedema?
Folds occur
Do endothelial cell numbers remain constant as we age? Can they regenerate if they are lost?
Cell numbers decrease with age and do not regenerate
How does drop toxicity appear with staining?
Small spots of fluorescein distributed evenly across the cornea
What constitutes filamentary keratopathy (2) and what is it usually due to (2)?
Usually due to abnormal areas of corneal epithelium and excess mucus in tears
Requires corneal irregularity in conjunction with tear film abnormality
In filamentary keratopathy, what adheres strongly to the corneal surface?
Filaments - mucous strands attached to abnormal epithelial cell plaques
Is filamentary keratopathy common? List 5 common causes of this condition.
Uncommon
Severe dry eye
Superior limbic keratoconjunctivitis
Ocular surgery (cataract/corneal graft)
Recurrent corneal erosion
Neurotrophic keratopathy
List 4 symptoms of filamentary keratopathy. Explain why they occur if applicable (3).
Foreign body sensation
-pulling on filaments with blink
watery eye
-due to stimulated reflex tears
Decreased VA
-due to filaments and poor tear flims
Photophobia
What appearance do filaments in filamentary keratopathy have? What colour and how long? What do they stain well with? What about fluorescein? Which end of the filament is adherent and to what?
Greyish filaments, one to several mm in length
Stains well with rose bengal and lissamine green
Less well with fluorescein
Adherent to corneal plaque at the proximal end of the strand.
List three components to assessing filamentary keratopathy.
Good history
Appropriate slit lamp and tear assessment
How are filaments in filamentary keratopathy treated? Are they recurrent?
What does removal of the filament cause and can it be treated?
They are removed under local anaesthesia using sterile forceps
Will reccur if the underlying cause isnt treated
Removal will cause an epithelial defect - topical antibiotic prophylaxis
Aside from treating the filament itself, list 4 treatment options for filamentary keratopathy.
Ocular lubricants
Topical corticosteroids if filaments are persistent
Bandage contact lens
Topical acetylcysteine
How common is superficial punctate keratopathy? What acronym is used for it? What is it due to?
Very common
Also called PEE
Due to superficial damage (erosion) of the surface corneal epithelium
List 8 common causes of superficial punctate keratopathy.
Dry eye
Drug toxicity
Foreign body
Contact lenses
Hyopxia
Lid disease
Corneal disease
Thygeson’s superficial punctate keratopathy
What three dyes does superficial punctate keratopathy stain with?
Fluorescein
Rose bengal
Lissamine green
What does the position of staining/erosion in superficial punctate keratopathy indicate?
It may determine cause
List symptoms of superficial punctate keratopathy (3).
May be asymptomatic
If symptomatic - gritty and photophobia
What may happen if superficial punctate keratopathy is dense?
Visiond loss
List 5 signs of superficial punctate keratopathy.
Fine, coarse, dense, or sparse areas of superficial corneal epithelial erosions
Eyes remain white and clear
List 6 components for assessing superficial punctate keratopathy.
History
Slit lamp
Fluorescein
Wratten filter
Tear workup
Identify underlying cause
Within what time period will superficial punctate keratopathy typically repair? What can promote repair?
Within 24h
Ocular lubricants can promote repair
If wearing contact lens and superficial punctate keratopathy is noticed, what advice should be given?
Discontinue contact lens wear
Are corneal infiltrates present with superficial punctate keratopathy?
No
What may be required if superficial punctate keratopathy is severe (3)?
Prophylactic topical antibiotic cover
Steroids
-only if underlying condition is inflammatory
Are subepithelial infiltrates common or rare? What are they due to?
Relatively common
due to inflammatory response within the anterior corneal stroma
-leukocyte infiltration
List 5 common causes of subepithelial infiltrates.
Viral infection
Blepharitis
Tygeson’s SPK
Preservative toxicity
Contact lenses
List 5 symptoms of subepithelial infiltrates.
Foreign body sensation
Photophobia
Watery eye
Decreased visiond if central
SPK over the area of infiltrate
How do subepithelial infiltrates appear? What may happen with the overlying epithelium?
Appears as a subepithelial, diffuse grey opacity
Overlying epithelium may stain with fluorescein
List 6 components for assessing subepithelial infiltrates.
History
Slit lamp
Fluorescein
Wratten filter
Tear workup
Identify underlying cause
What is a treatment option if subepithelial infiltrates are symptomatic?
Ocular lubricants
What should be done when treating subepithelial infiltrates?
Manage the underlying cause
What should be considered if there is significant epithelial breakdown over the infiltrate with subepithelial infiltrates?
Antibiotics
Can steroids be given for subepithelial infiltrates?
Yes, with a slow taper
Define CLARE-CIE and what it is.
Contact lens (induced) acute red eye
It is an acute inflammatory event
What can lead to CLARE? What does it lead to (2)?
Contact lens tight fit can lead to a stasis of the tear film, causing a buildup of bacterial population under the lens and limbal hypoxia
What is the hallmark sign of CLARE in a contact lens wearer?
Corneal subepithelial infiltrates
List 5 symptoms of CLARE.
Discomfort
Bulbar conjunctival redness
Irritation
Mild photophobia
Watery eye
Within what time period does CLARE typically resolve? What percentage reccurs and within what time period? Why does this occur (2)?
88% resolves by day 22
Recurrence rate is 30%
Most recurrence within 2 months
Possibly due to not treating inflammation effectively and returning to contact lens wear too early
Why are antibiotics administered concurrently with anti-inflammatories for CLARE management (4)?
Decrease bacterial load
More than normal discharge
Unsure of diagnosis
Optometrist peace of mind
Is CLARE inflammatory or infective, or both?
Inflammatory
How is inflammation in CLARE treated?
Steroids, which must be tapered
Is it ok to use ocular lubricants concurrently with steroids in CLARE?
Yes
What can be done to reduce recurrence of CLARE (3)?
No overnight wear
Change to high Dk
Change to dailies
Is neurotrophic keratopathy common or uncommon?
Uncommon
In what kind of eyes does neurotrophic keratopathy occur?
Diminished corneal sensation
What occurs with neurotrophic keratopathy in terms of metabolism and healing? List two additional consequences.
Decreased epithelial metabolism and healing
Reduced reflex aqueous tear production
Reduced epithelial trophic factors from nerves
List 6 common causes of neurotrophic keratopathy.
Previous herpes zoster or simplex keratitis
Surgery/tumours
Systemic diseases (diabetes)
Topical drug therapy
List 4 symptoms of neurotrophic keratopathy.
Photophobia
Conjunctival redness
Decreased vision
Pain unlikely
List three signs of neurotrophic keratopathy.
Range from SPK to large ulcers
Reduced corneal sensation
Surface or mild intra-ocular inflammation
Consider the ulcers with neurotrophic keratopathy. Do they usually have smooth/rough distinct/indistinct borders? What is their longest axis?
Smooth distinct borders
Longest axis is horizontal
List 8 components to assessing neurotrophic keratopathy.
History
Slit lamp
Fluorescein
Wratten filter
Lissamine green
Tear workup
Corneal senstivity
Identify underlying cause
What is the mainstay of treating neurotrophic keratopathy?
Non-preserved ocular lubricants
Aside from the mainstay treatment, list 5 additional treatment options for neurotrophic keratopathy.
Withdrawal of topical medications if any (if theyre causative)
Antibiotic ointment (chloramphenicol ointment)
Non-preserved topical steroids
Bandage contact lenses (increases infection risk)
Referral for tarsorraphy
Is bullous keratopathy common or uncommon?
Not uncommon
What does bullous keratopathy occur due to?
Endothelial decomposition causing stromal/epithelial corneal oedema
List 5 common causes of bullous keratopathy.
Post-operative endothelial damage
Endothelial dystrophy
Trauma
Angle closure glaucoma
Contact lenses
List 4 symptoms of bullous keratopathy.
Pain
Photophobia
Decreased VA
Haloes around lights
In what two regions does oedema occur with bullous keratopathy? for each, list two features.
Stromal corneal oedema
-corneal opacification and folds in descemets membrane
Epithelial corneal oedema
-microcystic changes, a roughened corneal surface
-bullae, distinct raised areas with negative staining
List 6 components to assessing bullous keratopathy.
History
Slit lamp
Fluorescein
Wratten filter
Specular microscopy
Identify underlying cause
List 4 treatment options for bullous keratopathy.
Non-preserved ocular lubricants
Hypertonic saline (5%) ads mainly the epithelium
Bandage contact lens
Refer for surgery
Is interstitial keratitis common or rare?
Very rare
What is interstitial keratitis?
Inflammation of the corneal stroma without primary involvement of the corneal epithelium or endothelium
List 5 symptoms of interstitial keratitis.
Congenital syphilis
Tuberculosis
HSV
HZV
Cogans syndrome
List 5 symptoms of interstitial keratitis.
Pain
Photophobia
Ocular ache
Increased tearing
Reduced vision
Is interstitial keratitis usually uni- or bilateral? Explain.
Bilateral if due to systemic disease
Unilateral with HSV/HZV infection
List 4 active signs of interstitial keratitis.
Stromal inflammation with oedema
Corneal opacities
Vascularisation
AC reaction
List 3 inactive signs of interstitial keratitis.
Corneal opacification
Corneal thinning
Ghost vessels
What is the treatment option for interstitial keratitis? What cause requires urgent referral and why?
Treat corneal inflammation with potent, frequent topical corticosteroid
Refer for treatment associated with systemic diseases
Urgent referral is required if Cogan’s is suspected as it can be life-threatening
List three symptoms of Cogan’s syndrome.
Tinnitus
Vertigo
Deafness
Is marginal keratitis common or rare? Is it uni- or bilateral?
Common unilateral
What is marginal keratitis and what four things is it associated with?
A unilateral peripheral corneal lesion associated with:
Staph. endotoxin hypelsensitivity
Blepharitis
Acne rosacea
Contact lens wear
List 5 symptoms of marginal keratitis.
Redness
Discomfort
Photophobia
Watery discharge
Blurred vision
How does the lesion of marginal keratitis appear in size, colour, and numbers?
Sub-epithelial grey/white opacities ~1mm in size, often multiple
What can sometimes overlie the lesions in marginal keratitis?
Small epithelial defect
What are inferior lesions in marginal keratitis associated with?
Blepharitis
List two signs of marginal keratitis.
Adjacent conjunctival redness
Rarely anterior chamber reaction
List a differential diagnosis for merginal keratitis.
Microbial keratitis
List the 5 components to assessing marginal keratitis.
History
Slit lamp
Fluorescein
Anterior chamber
Lids
List three treatment options for marginal keratitis.
Topical steroids for inflammation
Topical antibiotics for epithelial defect prophylaxis
Treatment of underlying lid disease
What kind of keratitis is marginal keratitis?
Peripheral keratitis
Is phlyctenulosis common or rare? Is it uni- or bilateral?
Uncommon unilateral
What does phlyctenulosis look like?
Raised conjunctival/corneal lesion (phlycten)
In what population is phlyctenulosis typically found?
Young children
List a possible cause of phlyctenulosis.
Hypersensitivity to bacterial endotoxin
What is phlyctenulosis mainly found with (2)? Is it common in children (this particular cause)?
Mainly found with staph. blepharitis (uncommon in kids) and tuberculosis (disease itself is uncommon)
List 5 symptoms of phlyctenulosis.
Redness
Discomfort
Photophobia
Watery discharge
Blepharospasm possible
List 6 signs of phlyctenulosis.
May be conjunctival, limbal, or corneal
A raised pink/white nodule
Ocassional overlying epithelial defect
Associated corneal/conjunctival vascularisation over weeks
List 4 differential diagnoses for phlyctenulosis.
Microbial keratitis
Marginal keratitis
Pingueculum
Granuloma
List the four components to assessing phlyctenulosis.
History (TB)
Slit lamp
Fluorescein
Lids (blepharitis)
What is recommended if there is concern for a tuberculosis caused case of phlyctenulosis?
Refer for a chest x-ray, mantoux and sputum culture
What is the treatment/management for phlyctenulosis?
Manage staph. lid disease if appropriate
Monitor for improvement
What kind of keratitis is phlyctenulosis?
Peripheral keratitis
Is moorens ulcer common or rare?
Rare
Describe moorens ulcer, including what its related to, its progression, and in which populations (gender included if applicable) in which it is more or less aggressive and if its uni- or bilateral.
An idiopathic, slowly progressive, ulcerative lesion of the peripheral cornea
-less agressive and unilateral in elderly
-more aggressive and bilateral in young males
List 4 symptoms of moorens ulcer.
Conjunctival redness
Pain
Photophobia
Mucus/watery discharge
List 2 signs of moorens ulcer.
Associated infiltrate
Stromal thinning
What two things may occur with aggressive forms of moorens ulcers? Is it common or rare?
Aggressive forms may result in corneal scarring and perforation
Is rare
How does moorens ulcer appear and where does it typically begin? What shape does it have? How long
Peripheral corneal ulceration with epithelial defect beginning nasal or temporal but crescent shaped and a number of clock hours long
List four differential diagnoses for moorens ulcer.
Other peripheral ulcerative changes
Microbial keratitis
HSV limbitis
HZO
What is the mainstay treatment for moorens ulcer? Is a referral needed?
Refer to establish diagnosis
Systemic steroids and other immunosuppressants mainstay
Topical steroids and prophylactic antibiotics also used
Is thygesons superficial punctate keratopathy common or rare? Is it uni- or bilatera?
Rare bilateral
What is the aetiology of thygesons superficial punctate keratopathy?
Unknown, but presumed viral
What is thygesons superficial punctate keratopathy?
Corneal inflammatory condition
When is the onset of thygesons superficial punctate keratopathy greatest?
Greatest in the second decade
What is thygesons superficial keratopathy characterised by (2)? How long does the active phase last for and how is the remission?
Remissions and exacerbations
Active phase - 1-2 months
Remissions - up to 2 months
Do thygesons superficial punctate keratopathy attacks tend to increase or decrease with age? Do they ever cease?
Tends to decrease
Ceases after many years
Does thygesons superficial punctate keratopathy resolve with or without sequelae? How long may it last?
Often resolves without sequelae after 2 -4 years but may last up to 20 years
List 4 symptoms of thygesons superfiical punctate keratopathy.
Photophobia
Tearing
FB sensation
May have mild decrease in vision
Describe the active phase of thygesons superficial punctate keratopathy. What kind of staining would be seen? Is there any haze on the epithelium or is it clear? Does it leave scars behind? What surface appearance does it give the cornea?
Raised epithelial lesions
Negative or no fluorescein staining
Can be faint epithelial haze
Never scars
Gives corneal surface appearance of having coarse breadcrmbs on the surface
What degree of conjunctival injection is present in the active phase of thygesons superficial punctate keratopathy?
Mild conjunctival injection
What number of lesions may be present during the active phase of thygesons superficial punctate keratopathy?
1 - 20 is the most common, can be more
What occurs during the inactive phase of thygesons superficial punctate keratopathy?
Lesions may disappear or leave flat epithelial grey area
List the three components to assessing thygesons superficial punctate keratopathy.
History
Slit lamp
Fluorescein
What is the mainstay treatment for thygesons superficial punctate keratopathy? When is the ideal time for this? What must be done if this treatment option is given? List 2 additional treatment options.
Mainstay is moderate strength topical steroid during exacerbation - greatly reduces course (careful tapering needed)
Bangage contact lens can reduce symptoms
Ocular lubricants for discomfort
IOP must be monitored if steroids are given
