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