Paediatric ophthalmology Flashcards
Appreciate these key points about paediatric ophthalmology
- Child’s visual system is constantly developing from birth until around 6 yrs of age.
- Most convergent squints are corrected by glasses.
- Babies with abnormal red reflexes should be referred urgently
What is amyblyopia ?
- Also know as ‘lazy eye’ this is where there is reduced vision usually in one eye due to a degraded retinal image
- It results from poor development of binocular visual pathways
What are the causes/classification of amblyopia ?
- Ametropic – bilateral uncorrected refractive error
- Strabismic – squinting eye is “suppressed”
- Anisometropic – unequal refractive error
- Stimulus deprivation – congenital cataract/ptosis
What is amblyopia treated with ?
- 1st line = Total occlusion (of the good eye) – Patching
- 2nd line = Partial occlusion – Pharmaceutical penalisation using Atropine 1%
What is the purpose of cover testing ?
To detect a manifest squint (tropia) or detect an underlying latent squint (phoria)
What are the causes of squints ?
- Congenital
- Hypermetropia (long sight)
- Cranial nerve palsies - III, IV, VI
- Muscle pathology
- Restrictive: Duanes, Browns, Fibrosis
- Myasthenia Gravis
- Orbital problems - Blow out fracture
When describing a squint what is the difference between a tropia & a phoria ?
A tropia is always present, while phorias are there “some of the time,” such as when the patient is tired or when fusion is broken (you cover an eye and it starts to drift).
What is an additional aspect which is useful to distinguish between tropias & phorias ?
Corneal reflexes:
- In tropias there will be asymmetric corneal reflections
- In phorias there will be symmetrial corneal reflections
Define what is meant when using the terms eso & exo to describe a squint
- ESO- eye is convergent/IN i.e tendancy of eye to deivate inwards (esotropia/esophoria)
- EXO- eye is divergent/OUT i.e. tendancy of eye to deivate outwards (Exotropia/Exophoria)
Define what is meant by the terms hyper and hypo when used to describe a squint ?
- HYPER- eye is higher = Hypertopia/Hyperphoria
- HYPO- eye is lower = Hypertropia/Hyperphoria
Note - when it says the eye it is referring to the squint eye
What type of squint is shown in this pic ?
Right exotropia
What type of squint is shown in this pic ?
Left hypertropia
What type of squint is shown in this pic ?
Left esotropia - fully accomodative
What is the management of paediatric squints ?
Maximise visual acuity:
- correct refractive error
- treat amblyopia
Treat squint if required:
- cosmetic: can be carried out at any age
- functional - if large infantile squints, significant residual squints or if chance of restoring binocular vision
What is the management of adult squints ?
Preserve/improve binocular single vision:
- temporary prisms on glasses
- orthoptic exercises
Botulinum Toxin (BTXA):
- used to temporarily paralyze EOM, can be used for px not suitable for Sx
EOM Surgery:
- functional
- cosmetic
What is shown in this pic ?
Retinoblastoma - Yellow reflex seen completely filling right pupil
