CLM - Contact Lens Complications - PAP Week 3 Flashcards
Are contact lens complications a major problem?
Yes, up to 50% of patients will experience at least one complication
What is the largest risk factor for microbial keratitis?
Contact lens wear
What are the four main factors that contribute to contact lens complications?
Inflammation, allergy, sensitisation
Mechanical rubbing / poor fit
Microbiological agents
Hypoxia
Between male and female, which is at higher risk of contact lens complications?
Male
List 5 risk multipliers for contact lens complications.
Dry eye Male Smoker Extended wear Lifestyle
What percentage of patients wearing contact lenses report at least one hygiene habit that puts them at risk of infection?
99%
Does a significant portion of contact lens wearers (RGP included) replace their lenses at an interval longer than recommended?
Yes, up to 90%
Compare the proportion of individuals storing or rinsing their lenses in tap water in soft vs rigid lens wearers.
Much higher in those wearing rigid lenses to use tap water vs soft lens wearers
What are the most common presenting complaints for contact lens complications (4)?
VA
Photophobia
Pain (quantify /10)
Red/itchy eye
What 9 things should be ruled out when evaluating a suspected contact lens complication case?
Viral HSV/HZV keratitis Chlamydia Rosacea Atopy Episcleritis/scleritis Oclar surface disease Corneal dystrophy/degeneration Autoimmune disease
What can a wratten filter reveal and how?
It enhances NaFl visibility and reveals subtle staining
Is rose bengal toxic to the ocular surface or is it like NaFl? Do either of these dyes sting? What about lissamine green?
Rose bengal is toxic and therefore stings.
NaFl does not.
Lissamine green is less toxic and irritating (vs rose bengal).
What is the purpose ofa grading scale (2)?
Allows monitoring over time
Allows monitoring between clinicians
Should decimals be used in grading scales?
Daryl says no, but this one said yes for more sensitivity in monitor change so idk
For the following grades, describe if action is usually taken (for contact lens complications): Normal (0) Trace (1) Mild (2) Moderate (3) Severe (4)
Normal - not required Trace - rarely required Mild - may be required Moderate - usually required Severe - definitely required
What is the recommended management for hypoxia related contact lens complications (2)?
Increase Dk/t or decrease WT
Maybe consider daily disposables
Why does epithelial loss cause pain?
It exposes nerve endings
How long does it take for superficial vs deep staining to heal? If the patient has superficial staining, can they still wear their lenses? What about deep staining?
Superifical - within 24h
-Patient can continue wearing lenses
Deep - within 1-2 days
-best id patient stops wearing lenses for 2-4 days (treat the cause in the meantime)
What should be considered if there is a defect to the corneal stroma (2)?
Consider prophylactic antibiotics
- 0.5% chlorsig
- aminoglycoside for better gram negative coverage
In what five ways does the eye prevent bacterial colonisation?
Cell shedding Wiping action of blinking Irrigation by lacrimal secretions Antimicrobials in tears Competition by resident microbes
If there are satellite lesions, what does it decrease the likelihood of the diagnosis being?
Bacterial MK
What are most cases of microbial keratitis caused by?
Pseudomonas sp.
What are two characteristics of an acanthamoeba infection?
Ring infiltrate and extreme pain
When is acanthamoeba infection generally diagnosed?
When bacterial management isnt working
Should you refer if there are any lesions on the visual axis?
Yes
Are there any safety concerns with adjunctive corticosteroid therapy for bacterial corneal ulcers?
No
What is the association between visual outcomes in individuals with bacterial keratitis and high-dose steroid treatment?
Significantly associated with better visual outcomes
List 5 factors that are significantly associated with visual outcomes in keratitis.
High dose steroid treatment Visual acuity on presentation Age group Cause of keratitis Infiltrate size/location
List three possible causes of infiltrates.
Poor compliance MGD / blepharitis Hypersensitivity -lens -solution -bacteria
List four management options for infiltrates.
Cease lens wear
Steroid/antibiotic
Change lens type/modality/WT
If infection suspected, treat as infectious
When should an infiltrate case be reviewed after initial assessment and management?
Review in 24h