Paediatric Ocular Pathology- Retina - Alistair Flashcards
What is the most common cause of visual blindness in children?
Cerebral visual impairment
What is the most important electrophysiology test?
ERG
What is the minimum age an EOG can be performed on and why?
7 years old because requires a lot of patient co operation
What are three ophthalmic tests that can be done to assess the retina?
- OCT
- Electrophysiology
- Ultrasound
What test should be the last thing you do at the end of your paeds examination?
Ophthalmoscopy
How do you assess the retina and optic nerve in detail? And why do we do this?
Using OCT and electrophysiology (ERG, EOG, VEP) because retinal signs and optic nerve disorders can be very subtle but also co-occur
What is used to conduct an ERG?
Skin or conjunctival electrode
What are the two frequencies an ERG is done at ?
2 & 30 Hz
What is presented with a VEP?
A flash or a pattern which tells you the intactness of the visual pathway - limited
What eye condition is normally associated with an absence of septum pellucidum (the middle of the brain that splits the two hemispheres)?
Optic nerve hypoplasia
Why are two frequencies used in an ERG?
2 Hz are for rods assessment
30 Hz are cone assessment
What do the patients of the two right ERGS have wrong with them and how do you know that ?
They have no cones, at 30 Hz there was no response
What classifies whether a baby is premature and how many people get affected by this?
Born before 37 weeks, affects 5-8%
Does vision start to develop from the preterm date (that is if the baby is premature) or the due date?
Due date
What are some signs of a preterm baby’s retina?
Not fully vascularised and thin vessels
What week of gestation do blood vessels come out the optic disc?
12-13 weeks
At what point of gestation is the retina fully vascularised?
Full term time
With pre term babies, as their retinas are not fully vascularised, where do their retinas get blood supply from?
Choroid
What are the two phases of retinopathy of prematurity (ROP)?
Acute phase and sequelae
How long does the acute phase last?
Only occurs until a few weeks until after birth
*we dont need to know details about what this is
What can severe ROP cause?
Blindness but can be prevented with timely screening
Can mild ROP resolve without major sequelae?
Yes :) just like anisha and hardeep
Where on the Retina does ROP develop?
At the junction between vascularised and non-vascularised retina
How many stages are there of ROP?
5
Which stages are classified into mild ROP?
Stage 1 and 2
What does stage 1 look like?
White line within the retina is formed
What is stage 2?
White line becomes a ridge
What is stage 3?
Ridge with extra retinal fibrovascular proliferation (similar to DM - has CWS and neovasc of bv coming out of the retina into the vitreous)
What stage is this?
3
What changes in regard to the BVs from mild ROP to stage 3 ROP?
Bv become thick and tortuous
If ROP is left untreated what might the child get?
An RD
What is stage 4 ROP?
Partial RD
What is stage 5?
Total RD
What is stage 5?
Total RD
Why is the risk for blindness greater in India than here?
They have a greater prevalence of pre term babies
Why is the screening programme for preterm babies tight?
There is a narrow window for treating babies with ROP (you have to catch the baby at exactly the right time)
What is treatment for severe acute ROP?
Cryotherapy, laser and AntiVEGF
What is cryotherapy?
Freezing the retina where the tear has occurred
What are patients who were born premature likely to have who have had NO or mild ROP?
Slightly reduced va and contrast
What acuity is a patient who has severe ROP likely to have?
Ranges from normal to blind
What acuity is a patient who has severe ROP likely to have?
Ranges from normal to blind
What acuity is a patient who has severe ROP likely to have?
Ranges from normal to blind
What % of preterm babies will have strabismus?
20% (it’s only 3% in full term babies!)
If a baby had severe ROP what is the likelihood of having strabismus? (%)
> 60%
What does prematurity do to the eye?
Cornea develops abnormally so they have a mild degree of keratoconous and myopia
What is a px who has had severe ROP likely to have?
Very high myopia (16-20D)
What is this ? + at what stages does it occur?
Dragged disc - this is temporal retina is pulling or dragging of the disc and vessels
Stage 3 or after
What are causes of a dragged disc?
- ROP
- Exudative vitreoretinopathies
- Norrie’s disease
- Congenital fold
*all of which are rare diseases
What is this? And what is that white stuff?
End stage ROP, px likely to be blind, retrofibroplasia is the white stuff
In baby what is the ONLY cause if a sub-conjunctival haemorrhage?
Trauma
If you see a retinal haemorrhage like this, what are you thinking could have happened to the baby?
Shaken baby syndrome
What is this disease?
Coat’s disease
What are some features of Coat’s disease?
- M>F
- Unilateral
- Retinal telangiectasia (massive exudates and RD)
- Systemic association
In the lecture just says know these vascular diseases exists, so down worry if you do not know this
What is this disease and some features of the disease?
Von Hippel Lindau syndrome
Bilateral, both sexes, tumours of the brain and retina
What is this disease ?
Sickle cell retinopathy
What people is sickle cell more prevalent in?
African or Mediterranean origin
What are some signs of the Retina with sickle cell retinopathy?
Peripheral occlusion of BV, neovasc, could regress or cause RD
What are five names of infections of the Retina?
- Toxoplasmosis
- Cytomegalovirus
- TB
- Rubella
- Toxocara
What does this px have?
Toxoplasmosis
What type of infection is toxoplasmosis?
Protozoa
How can you get toxoplasmosis?
Eating raw meat or eating food that has been contaminated by cat faeces
What else might someone with toxoplasmosis have?
Lesions to the brain, cataract, uveitis
What is toxocara?
Worm infection from a cat or dog
What is similar to toxoplasmosis?
Toxocara however, toxocara only occurs in one eye
What is this ?
Toxocara
Is rubella rare in this country?
Yes because we have all be vaccinated
What problems can someone who has rubella have?
Heart defects, deafness, mental retardation, small eyes, pigmented retinopathy
What does this px have and describe the fundus?
Speckled pigment giving a mottled appearance
(rubella- salt and pepper appearance)
What is someone with cmv likely to also have?
HIV
What does CMV stand for ?
Cytomegalovirus
What does this px have?
CMV
What ophthalmic issues is a px with CMV likely to have?
Microphthalmos, cataract, keratitis, optic atrophy
What are some stationary retinal dystrophies?
- Congenital night-blindness
- Achromatopsia
What does someone with congenital night blindness have a disorder of?
Rods (associated with myopia)
What are five signs of someone with achromatopsia will have?
- Reduced vision
- Photosensitivity
- Nystagmus
- High hyperopia
- Absent flicker on an ERG
- Normal looking retina
What is a disease of a child with a progressive rod-cone retinal dystrophy?
(There are three)
- Leber’s congenital amaurosis
- Retinitis pigmentosa
- Choroideremia
What signs would a child with Leber’s congenital amaurosis have?
Reduced vas
Nystagmus
High hyperopia
Normal Retina ( can later become pigmentary)
Flat ERG
If a child comes in with high hyperopia, nystagmus, reduced vas and sensitive to light, what two conditions should you be thinking of ?
Achromtopsia and Leber’s congenital amaurosis
What are four inherited macular dystrophies?
- Stargardt’s disease
- X-linked retinoschisis
-Best’s disease - Pattern dystrophy
As the signs are very subtle, what are the patients often labelled as?
Hysterical
What does leucocoria mean?
White pupil
Name some diseases with leucocoria
- Retinoblastoma
- Cataract
- ROP
- Developmental anomalies such as a Coloboma
- Coat’s disease
What is the most common malignant ocular tumour of childhood?
Retinoblastoma
Is a retinoblastoma likely to be bilateral or unilateral?
Unilateral
What are three presentations of someone with retinoblastoma?
Leucocoria, strab, glaucoma
What is treatment of retinoblastoma (it is a tumour remember)?
Chemotherapy
What does ROP mean?
Retinopathy Of Prematurity
Which stages are considered severe ROP?
Stage 3-5; they require treatment