CL related pathology

Question 1

what are the CL adverse events?

Answer 1

. ( A)IK - asymptomatic infiltrate keratitis
. SEAL - superior epithelial arcuate lesion
. CLPC - contact lens associated papillary conjunctivitis
. CLARE - contact lens acute red eye
. CLPU - contact lens peripheral ulcer
. MK - microbial keratitis

Question 2

what is asymptomatic infiltrative keratitis ?

Answer 2

. sterile corneal infiltrates - white dots in the cornea
. inflammatory cells from limbal vessels
. in response to hypoxia , bacteria , lens deposits , allergic reaction , poor hygiene

Question 3

what are the clinical signs of infiltrative keratitis ?

Answer 3

. eye moderately red and slightly watery

Question 4

what does patient complain of in infiltrative keratitis ?

Answer 4

. mild foreign body sensation

. mild photophobia

Question 5

what is the management of infiltrative keratitis ?

Answer 5

. temporary discontinuation
. most signs and symptoms resolve within 48 hours this is because bacteria doesn’t replicate
. infiltrates resolve over 2-3 weeks
. advice against Extended wear
. if reoccur , switch to daily disposable
. careful monitoring
. ocular lubricants and cold compresses for symptomatic relief

Question 6

what is superior epithelial arcuate lesion caused by?

Answer 6

. caused by mechanical pressure due to design or material

. this happens against the superior part of the cornea below the superior eyelid

Question 7

what does patient complain of when they have superior epithelial arcuate lesion?

Answer 7

. usually unilateral , asymmetric or mildly symptomatic
. irritation
. foreign body sensation

Question 8

what is the clinical presentation of superior epithelial arcuate lesion?

Answer 8

. arcuate staining in the cornea that can run form 10 o’clock to 2 o’clock within 1mm from limbus

Question 9

what is the current hypothesis of SEAL?

Answer 9

. SEAL are produced by mechanical chafing at the peripheral cornea

Question 10

what is SEAL management?

Answer 10

. cease CL wear for 1-7 days
. issue lubricants
. review lens fit or material 
. use thinner, more flexible lens material 
. change back surface geometry of CL

Question 11

what is contact lens associated papillary conjunctivitis ?

Answer 11

. conjunctival inflammation

. refers to appearance of localised swellings or papillae on tarsal conjunctiva

Question 12

where are papillae mostly found?

Answer 12

. papillae mostly observed in upper eyelid and observed by everting the lid

Question 13

what is the cause of contact lens associated papillary conjunctivitis ?

Answer 13

. immunological response due to hypersensitivity to lens deposits or solution or mechanical response due to lens design or modulus

Question 14

where are papillae found in RGP wearers ?

Answer 14

. they tend to be flatter

. located towards lash margin

Question 15

where are papillae in SCL wearers?

Answer 15

. located in upper tarasal plate

. they take more rounded form

Question 16

how do papillae appear ?

Answer 16

. they appear as round light reflexes giving irregular specular reflection

Question 17

how does tarsal conjunctiva appear in early stages of associated papillary conjunctivitis ?

Answer 17

. in less than grade 2

. the tarsal conjunctiva may be indistinguishable from the normal tarsal conjunctiva apart from increased redness

Question 18

how do papillae appear in advanced cases?

Answer 18

. when there is greater than grade 2 , papillae can exceed 1mm in dimeter and take bright red or orange hue

Question 19

what are other signs in contact lens associated papillary conjunctivitis greater than grade 3 ?

Answer 19

. conjunctival odema
. excessive mucus
. mild ptosis
. cornea may display superior infiltrates

Question 20

what is the aetiology of contact lens associated papillary conjunctivitis ?

Answer 20

. lens induced mechanical irritation

Question 21

how to manage CLPC?

Answer 21

. manage if grade >2
. lens wear can continue if symptoms permit
. improve lens hygiene ( cleaning and wearing time modality )

Question 22

what are other treatment options for CLPC ?

Answer 22

. altering the lens material
. replacing lenses more frequently
. altering or eliminating the care system
. treating any associated meibomian gland dysfunction
. prescribing pharamaceutical agents
. dispensing ocular lubricants for symptomatic relief
. reducing wearing time
. suspending or ceasing lens wear

Question 23

what is contact lens acute red eye?

Answer 23

. inflammatory response of cornea and conjunctiva subsequent to period of eye closure with CL wear

Question 24

what does px complain of with contact lens acute red eye?

Answer 24

. itching

. pain

Question 25

what is the cause of contact lens acute red eye?

Answer 25

. contact lens acute red eye occurs due to endotoxins from gram negative bacteria ( especially pseudomonas app )

Question 26

how is contact lens acute red eye characterised ?

Answer 26

``` . unilateral . epiphora . ocular irritation . anterior chamber reaction . acute hyperaemia . diffuse infiltrate keratitis ```

Question 27

what are the risk factors of contact lens acute red eye?

Answer 27

. upper respiratory tract infection . high water content CLS . tightly fitted lenses

Question 28

what is the management of CLARE ( contact lens acute red eye ) ?

Answer 28

. self limiting . temporary discontinuation CL wear . careful monitoring

Question 29

what is the recurrence of CLARE ?

Answer 29

. 50 -70 %

Question 30

what are signs of CLARE similar to ?

Answer 30

. similar to microbial keratitis . it's important to instil fluorescence and assess the corneal integrity for any epithelial disruption . CLARE doesn't usually have epithelial disruption

Question 31

what do corneal ulcers present with ?

Answer 31

. conjunctival redness . white spot in iris . corneal haze in mid peripheral cornea

Question 32

what are predisposing factors of corneal ulcers ?

Answer 32

``` . trauma . corneal surgery . ocular surface disease . systemic diseases . immunosuppression . CL wear ```

Question 33

what is the presentation of corneal ulcers ?

Answer 33

``` . red eye . pain . photophobia . watering . visual disturbance ( depending on cause and severity ) ```

Question 34

what are differential diagnosis of corneal ulcers?

Answer 34

. non-infectious corneal ulcers such as : - marginal keratitis - peripheral ulcerative keratitis - sterile corneal infiltrates associated with CL wear and toxic keratitis ( solution/eye drops )

Question 35

what is the difference of CL peripheral ulcers and infectious microbial keratitis ?

Answer 35

. infectious ulcers are caused by fungus or a virus or parasite or bacteria . non-infectious ulcers are caused by auto-immunity and marginal keratitis and allergy and inflammation from blepharitis or chemical burn

Question 36

what to do when you find an ulcer ?

Answer 36

. measure and record size and shape of epithelial defect and infiltrate, location, depth , margin and colour of ulcer . look for anterior chamber reaction

Question 37

what is severe anterior chamber reaction a characteristic of ?

Answer 37

. superlative infective keratitis which occurs subsequent to corneal trauma and can be initiated by airborne particles

Question 38

what information does NaFI staining give?

Answer 38

. presence of dendrites . loose/exposed sutures . epithelial defects . ocular surface disease

Question 39

what does a dendritic pattern mean ?

Answer 39

. mostly likely herpes keratitis

Question 40

what does localised punctate staining mean ?

Answer 40

. acanthamoeba keratitis

Question 41

what are differential diagnosis of contact lens-associated infiltrative events?

Answer 41

1. contact lens-associated peripheral ulcer ( CLPU ) 2. contact lens associated infiltrative keratitis ``` these Differential diagnosis are - microbial ( bacterial or fungal ) keratitis - marginal keratitis - corneal scar - herpes simplex keratitis - adenovirus keratoconjunctiviits ```

Question 42

what is microbial ( bacterial or fungal keratitis ) also similar to ?

Answer 42

. similar to ulcer . it is important to monitor closely especially over the first 24 hours and if diagnosis remains in doubt , refer to ophthalmologist as an emergency

Question 43

how to differentiate between contact lens pathologies ?

Answer 43

. ask specifically about contact with chemicals, CL hygiene, previous herpetic infection , chronic dry eye and ocular surface problems . systemic history should include : diabetic status , rheumatoid arthritis , Sjogren's syndrome , systemic immunosuppressants

Question 44

what are different cause of bacterial ulcers ?

Answer 44

1 . gram positive - causes a well circumcised ulcer 2. staph - round or oval lesions with dense infiltration and a distinct border 3. gram negative - poorly defined infiltrates with copious mucopurulent discharge 4. pseudo monas - rapid progression , dense stromal infiltrate and corneal perforation

Question 45

what are the common viral ulcer pathogens ?

Answer 45

1. herpes simplex - dendritic epithelial staining including terminal bulbs - look for associated skin lesions 2. herpes zoster - smaller and finer dendritic lesions , tapered ends without terminal bulbs 3. adeno viral - ' adeno-spots' subepithelial deposits with punctate staining associated with recent upper respiratory tract infection with conjunctivitis

Question 46

what is the diagnosis of acanthamoeba ?

Answer 46

. irritation corneal nerves

Question 47

what are the clinical signs of acanthamoeba ?

Answer 47

. subtle irregular corneal surface and punctate staining ( or dendritic ) . gradual enlargement and coalescence of infiltrates . inflammation or corneal nerves . raised ulcers

Question 48

what is the cause of acanthamoeba?

Answer 48

. history of CL wear with poor hygiene or water contact

Question 49

what is the difference between acanthamoeba and herpes zoster ?

Answer 49

. ulcers are raised in acanthamoeba and do not stain with fluorescence

Question 50

what is fungal keratitis ?

Answer 50

. not associated with contact lenses . systemic immunosuppression or long-term use of topical steroids . yeast : yellow-white dense suppurative infiltrate . aspergillus/fusarium : yellow-white stromal infiltrate with fluffy margins and feathery extensions and hypopyon

Question 51

what is the management of bacterial keratitis with small infiltrates or peripheral location?

Answer 51

. broad spectrum topical antibiotics

Question 52

what is the management of central , large , deep stromal infiltrates ?

Answer 52

. corneal scrape and topical antibiotic therapy

Question 53

when do we admit px to hospital ?

Answer 53

. if px is not compliant not with treatment in the initial days

Question 54

when do we use antibiotics ?

Answer 54

. antibiotics are preferred for infective ulcers . ointments for overnight . systemic antibiotics in severe cases

Question 55

when do we use cyclopegics?

Answer 55

. pain relief . helps with decreasing bacterial load . debriding helps with penetration

Question 56

when do we use steroids?

Answer 56

. to reduce inflammation and increase comfort once clinical signs have improved

Question 57

what is the management of microbial keratitis ?

Answer 57

. remove and retain CLs for culture . emergency same day referral to an ophthalmologist without any intervention . phone the department to explain what you have done

Question 58

what is management of viral specific ulcers such as herpes simplex keratitis ?

Answer 58

. this should include ruling out vasculitis , intra retinal haemorrhages and vitreous inflammation . Ganciclovir 0.15% ophthalmic gel: 5x daily 7-10 days and refer within one week ( if not healed after 7 days ) . or same day referral for children , bilateral , CL wearers or stromal involvement

Question 59

what is the management of herpes zoster zoster ophthalmicus ?

Answer 59

. rest, fluids , diet , no contact with babies , pregnancy and elderly . topical lubricants for ocular relief and pain relief . refer immediate GP ( skin lesions ) or one week ( deep , uveitis , IOP raised ) or co-manage if epithelial only

Question 60

what is the management of adeno virus ?

Answer 60

. artificial tears . lubricating ointments . topical antihistamines . refer same day in case of severe conjunctivitis or significant keratitis ( severe pain/ visual loss)

Question 61

what is the management of acanthamoeba keratitis ?

Answer 61

. same day ophthalmology referral . no intervention for optometrist . call ahead . advice to take CLs and case for possible culture

Question 62

what is the management of fungal keratitis ?

Answer 62

. same management of acanthamoeba keratitis . same day referral . call ahead . advice to take CLs and case for possible culture