Soft contact lens complications Pt 1 Flashcards
which 2 ways can contact lens complications be classified as
- according to their aetiology/origin
or - according to the ocular structure affected e.g. cornea, lid, conjunctiva etc
list the 7 categories SCLs complications can be classified into
- Metabolic influences
- Chemical influences
- Toxic reaction
- Allergic reaction
- Mechanical influences
- Tear deficiency
- Infection
give 3 examples of metabolic influences of SCL complications
- Hypoxia
- Hypercapnia
- Changes in osmolarity
give an example of chemical influences of SCL complications
Solution with a different pH
give an example of a toxic reaction of SCL complication
reaction to preservative
give 2 examples of allergic reactions to SCLs
- Hypersensitivity to care regime
- CL deposition
give 2 examples of mechanical influences of SCL complications
- Lens edge
- Lens break/damage
give an example of a tear deficiency SCL complication
dehydration
give 2 examples of infections of SCLs
- Bacterial
- Fungal
list 4 complications of the eyelid
- lid wiper epitheliopathy
- blinking abnormalities: causing SMILE staining from incomplete blink
- MGD
- ptosis
in which type of SCL wearing patients if ptosis more common in and by how much
Soft CL wear approx. 5x more common in young px who developed unexplained
acquired ptosis
Soft CL wear has been reported as the most common ______ _________ for ________ in patients under ___ years old
Soft CL wear has been reported as the most common risk factor for ptosis in patients under 35 years old
what is the cause of ptosis induced by SCLs
likely to be abnormal force on eyelids during I+R or/and intrinsically weak elevator aponeurosis
what are the 2 SCL complications of the limbus
- redness
- Superior limbic keratoconjunctivitis
what is limbal redness
Limbal vascular arcadesseries
of blood vessels within the limbus
what is common in most CL wearers
mild limbal hyperaemia
what was the outcome of a study that compared the extent of limbal and bulbar redness in subjects wearing EW low Dk SCLs in one eye and no lens in the other eye over a period of 5 years
that there was not much difference between these patients in bulbar redness, but more of a difference between the eyes in limbal redness for the patients wearing SCLs, therefore redness around the limbus is more apparent than the bulbar for SCL users
which type of SCL induces less limbal redness that standard low Dk hydrogel lenses
silicone hydrogel lenses = eyes appear whiter with these lenses
list the 7 possibles aetiologies of limbal redness
- Hypoxia
- Infection
- Inflammation
- Trauma
- Solution toxicity/hypersensitivity
- Lens deposits
- Mechanical
why is limbus redness one of the first signs in SCL wearers
because theres lots of blood vessels around the limbus
list the 6 management steps for limbal redness
- Record-use grading scale (and write what scale used)
- Cease lens wear
- Refit with high Dk lens/SiH
- Reduce wear time
- Alter lens fit
- Review care regime
what is another name for superior limbic keratoconjunctivitis
Contact lens induced superior limbic keratoconjunctivitis (CLSLK)
which 5 structures of the eye does Contact lens induced
superior limbic keratoconjunctivitis (CLSLK) involve
- corneal epithelium
- corneal stroma
- limbus
- bulbar conjunctiva
- tarsal conjunctiva
what can be seen in the slit lamp with someone who has Contact lens induced
superior limbic keratoconjunctivitis (CLSLK)
superior limbic redness and corneal staining
Contact lens induced
superior limbic keratoconjunctivitis (CLSLK) is an inflammatory reaction of…..
the superior cornea
what is Contact lens induced
superior limbic keratoconjunctivitis (CLSLK) associated with
CL solutions containing thimerosal (toxic substance)
when has there been a reduced prevalence of Contact lens induced
superior limbic keratoconjunctivitis (CLSLK)
since the use of thimerosal has declined
as well as thimerosal, what else can Contact lens induced
superior limbic keratoconjunctivitis (CLSLK) also occur as a response to
hypoxia or allergy
what are the 4 management options for a patient with Contact lens induced superior limbic keratoconjunctivitis (CLSLK)
- Solutions-without added preservatives (hydrogen peroxide) - Or switch to a different multipurpose solution - Change to daily disposables (if due to allergy as it cuts out solutions and deposits) - Reduce wear time (if due to hypoxia)
list 7 conjunctival complications related to SCLs
- redness
- lid wiper epitheliopathy
- conjunctival epithelial flap
- palpebral conjunctival changes
- papillary conjunctivitis
- staining
- lid parallel conjunctival folds (LIPCOF)
list 4 possible palpebral changes
- hyperaemia
- papillae
- follicles
- concretions
what is hyperaemia of the palpebra the first sign of
inflammation
what are papillae
Raised areas on the palpebral conjunctiva
what do papillae have that follicles dont have
a central blood vessel
what appearance of papillae is indicative of giant papillary conjunctivitis or vernal keratoconjunctivitis
Presence of papillae on the upper tarsal conjunctiva >1.0mm diameter
what are follicles
Focal accumulations of white blood cells within the palpebral conjunctiva without a central blood vessel
what are follicles associated with
viral infections
what is follicles not related to
contact lenses
what is the difference in location of papillae and follicles
- papillae are found under upper eyelid only
- follicles are found on the lower lid mainly and sometimes under the upper eyelid
what are concretions
Pale yellow accumulations of inorganic type material beneath palpebral conjunctival epithelium
what symptom may concretions cause
FB sensation
what are concretions not related to
contact lenses
what 2 palpebral changes are not related to contact lenses
- follicles
- concretions
what type of questions do you want to ask your patient to see if they have papillae
when the patient takes the lenses out, do they notice any roughness when blinking? do they have these same symptoms when they have their lenses in?
when the lenses are in, the patient will not feel the roughness from the papillae because the CL acts as a barrier over the cornea
which regions of the palpebra are considered most relevant in CL wear
1, 2 and 3
what should you use when recording changes to the palpebra
a grading scale e.g. CCLRU
list the 5 signs of papillary conjunctivitis
- Papillae
- Redness – Hyperaemia
- Mucus discharge
- Lens deposition
- Excessive lens movement
list the 3 symptoms of papillary conjunctivitis
- Px may have blurred vision due to lens deposits, mucus
- May have itching
- May have FB sensation
which grade of papillary conjunctivitis is considered to be giant papillary conjunctivitis
grade 4 - severe
when the papillae are larger than 1mm
as papillary conjunctivitis starts to get worse, where do the papillae tend to build up
along the bottom of the inverted eyelid
list 6 possible causes of papillary conjunctivitis
- Allergic (e.g. protein deposits on lens) or
- Mechanical (lens design, modulus of lens material)
- Hypersensitivity reaction mediated by Immunoglobulin E (IgE)
- Associated with soft CL wear and stiffer materials e.g. SiHy
- Associated with sensitivity to solutions or preservatives
- Associated with MGD
and atopy
what is atopy
a hypersensitive type of patient with allergies
list the 5 management options for papillary conjunctivitis and what must a patient have on them incase they can’t wear their lenses
- Improve lens care regime
- Daily disposables (if can’t clean lenses properly)
- Alter lens design or material (not SiHy)
- If required- mast cell stabilisers
- Manage any lid margin disease
pc must have a spare pair of glasses on them
what are the 3 types of conjunctival redness/hyperaemia
- sectoral
- interpalpebral
- bulbar
what is the likely cause of a sectoral conjunctival hyperaemia
a specific cause such as an infiltrate or eyelash rubbing against the eye
what is interpalpebral hyperaemia associated with
- chronic dryness and RGP wear
- it can be a allergic and/or mechanical cause
what is bulbar hyperaemia most common with and also associated with
- common with soft CL wear
- also a sign associated with many other serious conditions e.g. scleritis, uveitis
if a bulbar hyperaemia is due to other more serious conditions, how may you rule this out
to do tests such as IOPs, van herrick, visions, staining, anterior chamber
what are the 8 management options for conjunctival redness
- Record-use grading scales (so somebody else can monitor)
- Identify and address cause (do a ddx)
- Refit- change lens design (e.g. looser)
- Refit-change lens material e.g. different modulus or Dk
- Refit- more frequent replacement (if protein deposits)
- Review care regime
- Ocular lubricants
- Consider environmental factors
name 2 main causes of conjunctival staining
- Usually related to lens edge
(tight fit or excessively loose lens
moving too much) and/or dryness - Could be caused by solution
toxicity
what is the staining type of conjunctival staining and what can be used to enhance its appearance
- may be punctate or confluent staining
- could use written filter to enhance fluorescein visibility
- lissamine green is also useful
when can conjunctival staining start to get dangerous
when it encroaches onto the cornea
what causes a furrow/arcuate conjunctival staining and which lenses is it associated with
- when the superior lid comes down and presses on the CLs
- associated with tight fitting, high modulus or overnight wear/EW lenses
what does the management go conjunctival staining spend on
the cause
what is the management of conjunctival staining if it is due to dryness
treat with lubricants or take other appropriate action e.g. if down to MGD
what is the management of conjunctival staining if it is due to the lens fit
refit the lens e.g. to a lower modulus lens e.g. if it was originally SiHy lens
what is a conjunctival epithelial flap
Areas of loose conjunctival tissue
in area of lens indentation
where is conjunctival epithelial flaps usually located
superiorly or inferiorly
what is conjunctival epithelial flaps associated with and what does this cause
Silicone Hydrogel CL wear - which causes superficial layers of conjunctival cells to delaminate
what is delimitation of conjunctival cells (found in a conjunctival epithelial flap)
the layers split into individual sheets and is lose
which type of contact lens wearers is conjunctival epithelial cells found in as well as SiHy
RGP wearers
what are the 3 management options of conjunctival epithelial flaps
- Usually resolves upon ceasing CL wear
- Use lower modulus lens
- Reduce overnight wear