Amblyopia Flashcards
What is a visual screening?
A child is screened for eye problems
What is the purpose of visual screening?
Detect defects early so treatment done early before they become permanently visually impaired
When is the first ever screening that happens in a child’s life?
When they are born before they leave hospital
When are they next checked?
By doctor at 6 weeks
What exactly does the screening at this early stage entail?
Red reflex and eye development checked
What happens if a problems is found?
The child is referred for a full eye test
Who can detect strabismus?
Parents, health visitors, doctor
Which children should be more closely monitored?
FH of strabismus/amblyopia/refractive error
Child with systemic disease, hearing loss, learning difficulty, premature/low birth weight
What is a pre-school vision screening?
At age 4-5, child has a visual screening at school but this is not done everywhere
Who are the children screened by at pre school screening?
By orthoptists or
By professionals trained by orthoptists
What is the gold standard test at this screening?
Linear logMAR
What do you do before you being testing a child’s vision?
- Gain consent parent (opt-in/opt-out)
Gain consent - Explain the test procedure to the child.
Have a quick practice - Check child is able to match or name the letters at NEAR
How should you check the child’s vision?
Avoid pointing inside box, test each eye monocularly, always start with the RE unless they have strabismus, if poor result with first eye then quickly move on to second eye
If they have glasses check VA with them
What test chart can be used for 3.5-5 yr olds?
Crowded keeler logMAR
What distance for Crowded keeler logMAR?
3m
How many letters are used Crowded keeler logMAR??
Six letters are used X V O H U Y.
How many letters on each line of Crowded keeler logMAR?
4 letters surrounded by crowding bars
What is the score of each letter with Crowded keeler logMAR?
0.025
What are the advantages of Crowded keeler logMAR?
Easy to use, durable, 2 flip over books and matching card.
What’s the point of 2 books for Crowded keeler logMAR?
Incase they memorise it you have another book, use 1 book for each eye)
How do you conduct the Crowded keeler logMAR?
Test the right eye first using screening card S2
If the child is unable to identify the first letter on the S2 screening card, moves to screening card
S1
Test all letters on start line
proceeds to smaller / larger lines as necessary
2 letters per line must be correctly identified before testing smaller lines
Test all letters on the line where errors occur
tests all letters on 0.200 line if seen (testing can be stopped if this level of acuity is achieved)
correctly identifies the corresponding Keeler logMAR score, and records immediately after testing each eye
What should you ensure and observe for when conducting the test?
Ensure the child holds head straight during the test
observes the child during testing for abnormal head posture such as turning or tilting the head, or attempting to ‘peep’ from behind occlusion.
What is the main condition that screening is trying to detect and why?
Amblyopia because needs to be treated early
What others conditions you might detect?
Refractive error Strabismus Nystagmus Ptosis Muscle problem Cataract Anisocoria Rare pathologies: Coloboma, Leucocoria
What is amblyopia?
A form of cerebral visual impairment with reduced vision in one or both eyes, only occurs during critical period
What is the critical period?
Birth to 7-8 years old
