4. Paediatric Ophthalmology

Question 1

What is amblyopia?

Answer 1

Amblyopia is reduced vision in one or both eyes caused by abnormal visual development early in life, despite no structural eye abnormalities.

Question 2

What is the meaning of “You see nothing and the child sees nothing” in amblyopia?

Answer 2

It reflects that both the examiner and the child cannot see clearly from the affected eye because the brain suppresses the visual input from that eye.

Question 3

What are the common causes of amblyopia?

Answer 3

The main causes are:

Strabismus (misalignment of the eyes)

Refractive errors (unequal focus between eyes)

Deprivation (e.g., cataract or ptosis blocking vision)

Question 4

At what age is amblyopia treatment most effective?

Answer 4

Treatment is most effective before age 7–8 years, when the visual system is still developing.

Question 5

How is amblyopia diagnosed?

Answer 5

Diagnosis involves detecting reduced visual acuity not correctable by glasses, along with history and eye exam ruling out structural causes

Question 6

What is the main principle of amblyopia treatment?

Answer 6

To force the brain to use the weaker eye by patching or penalizing the stronger eye to improve vision in the amblyopic eye.

Question 7

What is the typical management of amblyopia due to strabismus?

Answer 7

Correct the eye alignment (surgery or glasses) and use occlusion therapy to improve visual acuity in the amblyopic eye.

Question 8

What happens if amblyopia is untreated?

Answer 8

Permanent visual impairment with poor vision in the affected eye and loss of binocular vision.

Question 9

Can amblyopia occur in both eyes?

Answer 9

Yes, especially in cases of bilateral high refractive errors or bilateral deprivation.

Question 10

Why is early screening important in paediatric ophthalmology?

Answer 10

To detect amblyopia early when treatment can still restore vision and prevent lifelong visual disability.

Question 11

What is the role of the lateral geniculate body (LGB) in vision?

Answer 11

The LGB receives visual input from both eyes and relays this information to the cerebral cortex for processing.

Question 12

What happens to the LGB if visual input is disrupted during the critical period of visual development?

Answer 12

The layers of the LGB corresponding to the affected eye atrophy, along with their areas in the cerebral cortex.

Question 13

When is the critical period for visual development in children?

Answer 13

The first 8 years of life.

Question 14

Why can the eye appear anatomically normal in amblyopia despite poor vision?

Answer 14

Because the problem lies in disrupted neural input to the brain (LGB and cortex), not in the eye’s structure itself.

Question 15

What is essential for preventing permanent vision loss in amblyopia related to LGB disruption?

Answer 15

Early treatment of the underlying cause of amblyopia during the critical period.

Question 16

How does disruption in input to the LGB affect the cerebral cortex?

Answer 16

The corresponding cortical areas also undergo atrophy, worsening visual deficits.

Question 17

What is deprivation amblyopia?

Answer 17

Amblyopia caused by something blocking vision, like a cataract or ptosis covering the visual axis, preventing normal image formation.

Question 18

What is ametropic amblyopia?

Answer 18

Amblyopia caused by high refractive errors in one or both eyes or a large difference in refractive error between the eyes, leading to blurred images.

Question 19

How does strabismic amblyopia develop?

Answer 19

When one eye sends a clear but misaligned image, the brain suppresses this image to avoid double vision, causing reduced vision in that eye

Question 20

Why does the brain suppress the image from the deviated eye in strabismus?

Answer 20

To prevent diplopia (double vision) and confusion.

Question 21

Can amblyopia occur if both eyes have high refractive errors?

Answer 21

Yes, if both eyes have high refractive errors, visual development can be impaired, leading to amblyopia.

Question 22

Give examples of causes of deprivation amblyopia.

Answer 22

Cataract and ptosis occluding the visual axis.

Question 23

Why is early detection important in amblyopia?

Answer 23

Amblyopia is much easier to treat if detected early, ideally during the critical visual development period.

Question 24

What simple test can help detect causes of amblyopia early?

Answer 24

The red reflex test.

Question 25

What conditions should prompt referral to an eye specialist in children?

Answer 25

Leucocoria (white pupil) Squint (strabismus) Ptosis Suspected refractive error

Question 26

What might leucocoria indicate in a child?

Answer 26

It could be a sign of cataract or retinoblastoma—both are urgent causes of visual impairment.

Question 27

What should you do if a mother says her child is not seeing well?

Answer 27

Take the concern seriously—parental concern is often accurate and should prompt further assessment.

Question 28

How can vision be assessed in young children using occlusion?

Answer 28

By covering one eye and observing their reaction—if the better eye is covered, a child with amblyopia may become distressed or stop focusing on objects.

Question 29

What simple method can be used to assess vision in older children?

Answer 29

Offer very small sweets like "100’s & 1000’s" or silver balls and observe whether the child can pick them up, indicating visual acuity and coordination.

Question 30

What is the purpose of patching/occlusion therapy in amblyopia?

Answer 30

To cover the stronger eye, forcing the brain to use the weaker eye, which stimulates the underdeveloped visual pathways.

Question 31

Which eye is patched in occlusion therapy for amblyopia?

Answer 31

The eye with better vision is patched to stimulate use of the amblyopic (weaker) eye.

Question 32

Which is worse in terms of visual development: myopia or hyperopia?

Answer 32

Hyperopia (long-sightedness) is worse for visual development.

Question 33

Why is hyperopia worse than myopia in children?

Answer 33

Because both distant and near images are blurred, giving the brain very little clear visual input to stimulate development.

Question 34

Why is myopia less harmful to visual development than hyperopia?

Answer 34

In myopia, near objects appear clear, so the brain still receives some visual stimulus, helping visual pathways to develop.

Question 35

When can mild congenital ptosis be left untreated initially?

Answer 35

It can be left until the child is preschool age and then operated on for cosmetic reasons if needed.

Question 36

When should a child with ptosis be referred urgently?

Answer 36

If the ptosis obstructs the visual axis or the child adopts an abnormal head posture.

Question 37

Why is abnormal head posture in a child with ptosis concerning?

Answer 37

Because it can interfere with normal development, such as delaying walking, and indicates the child is compensating for poor vision.

Question 38

How do haemangiomas typically behave in early infancy?

Answer 38

They often start very small, grow rapidly in the first few months, and then gradually regress.

Question 39

How can upper lid haemangiomas affect vision?

Answer 39

They can cause mechanical ptosis, which may lead to amblyopia if the visual axis is obstructed.

Question 40

When should a haemangioma be referred urgently?

Answer 40

If the pupil is partly or fully covered by the haemangioma, as it risks visual development.

Question 41

What is a commitant squint?

Answer 41

A squint where the angle of deviation stays the same in all directions of gaze.

Question 42

What type of squint is most common in children?

Answer 42

Commitant squint.

Question 43

What is an incommitant squint?

Answer 43

A squint where the angle of deviation changes depending on the direction of gaze.

Question 44

What is a common cause of incommitant squints?

Answer 44

Cranial nerve palsies.

Question 45

What is a tropia?

Answer 45

A tropia is a manifest squint that is visible when both eyes are open.

Question 46

How can a tropia be easily diagnosed?

Answer 46

Using the corneal light reflex test.

Question 47

What is a phoria?

Answer 47

A phoria is a latent squint that only becomes apparent when one eye is covered.

Question 48

Do all phorias require diagnosis or treatment?

Answer 48

No—small phorias are often normal and self-correct when both eyes are open, so they usually don’t need to be diagnosed or treated.

Question 49

What is the first step in using the corneal light reflex to detect a squint?

Answer 49

Ask the patient to look directly at a pen torch.

Question 50

Where should the pen torch reflection be seen if the eyes are aligned properly?

Answer 50

The light reflex should be centred on the pupil and symmetrical in both eyes.

Question 51

What does an off-centre corneal light reflex indicate?

Answer 51

The presence of a squint (strabismus).

Question 52

What is an accommodative cause of squint in children?

Answer 52

Hyperopia (long-sightedness) causing the child to over-focus, leading to a squint.

Question 53

How does heredity play a role in squint development?

Answer 53

Many squints run in families, suggesting a genetic component.

Question 54

What is a sensory cause of squint in a child?

Answer 54

Blindness or poor vision in one eye, causing the eye to drift.

Question 55

What neurological factors may contribute to squint?

Answer 55

Underlying neurological conditions or developmental delay.

Question 56

When should a squint in a child be referred?

Answer 56

If the squint appears after the age of 6 months.

Question 57

Why does a hyperopic child need to accommodate strongly?

Answer 57

To produce a clear image for near objects.

Question 58

What reflexes are stimulated when a hyperopic child accommodates?

Answer 58

Accommodation stimulates convergence and pupil constriction (the accommodative reflex).

Question 59

How can correcting hyperopia help treat squint?

Answer 59

It removes the drive to accommodate, thereby reducing excessive convergence and helping to correct the squint.

Question 60

When do retinal vessels first appear during fetal development?

Answer 60

At 16 weeks, starting at the optic disc.

Question 61

By what age do retinal vessels reach the nasal ora serrata?v

Answer 61

By 8 months gestation.

Question 62

When do retinal vessels reach the temporal ora serrata?

Answer 62

By 9 months gestation.

Question 63

How do retinal vessels develop during gestation?

Answer 63

They start at the optic disc and gradually extend peripherally towards the ora serrata.

Question 64

When is the retina fully vascularised in normal development?

Answer 64

At full term (around 40 weeks gestation).

Question 65

What neonatal factors disrupt retinal vascular development and cause ROP?

Answer 65

Prematurity and exposure to supplemental oxygen.

Question 66

What serious complication can ROP lead to?

Answer 66

Tractional retinal detachment, similar to proliferative diabetic retinopathy.

Question 67

What oxygen saturation range should be maintained in premature infants to minimize ROP risk?

Answer 67

Between 86% and 92%.

Question 68

Which premature babies should be screened for ROP?

Answer 68

Babies born before 32 weeks gestational age or weighing less than 1500 grams.

Question 69

Who should perform the ROP screening examination?

Answer 69

An ophthalmologist.

Question 70

What are the treatment options for severe ROP?

Answer 70

Laser therapy or Avastin (anti-VEGF) injections.

Question 71

What is the goal of treating severe ROP?

Answer 71

To prevent retinal detachment and blindness.

Question 72

What is the most common primary malignant intraocular cancer in children?

Answer 72

Retinoblastoma

Question 73

What key clinical sign in a child should raise suspicion for retinoblastoma?

Answer 73

Leucocoria (white pupil) or an abnormal red reflex.

Question 74

What should leucocoria or abnormal red reflex be considered until proven otherwise?

Answer 74

Retinoblastoma

Question 75

What can happen if diagnosis of retinoblastoma is delayed?

Answer 75

Bilateral blindness by age 2, or a fungating tumour by age 2½.

Question 76

What are the key warning signs that should prompt urgent referral for possible retinoblastoma?

Answer 76

Leucocoria (white pupil) or abnormal red reflex Squint A red eye in a child that does not improve.

Question 77

What is Ophthalmia Neonatorum?

Answer 77

An eye infection in a newborn transmitted through the birth canal.

Question 78

What organism causes hyperacute conjunctivitis in days 1–3?

Answer 78

Gonococcus (Neisseria gonorrhoeae).

Question 79

Why is gonococcal conjunctivitis dangerous in neonates?

Answer 79

It can perforate an intact cornea.

Question 80

What is the main immediate treatment for gonococcal ophthalmia neonatorum?

Answer 80

Frequent eye irrigation (every 15 minutes) with saline or antibiotic drops (e.g., gentamycin).

Question 81

What systemic treatment is given for gonococcal ophthalmia neonatorum?

Answer 81

Intramuscular ceftriaxone.

Question 82

Why must the mother and partner also be treated?

Answer 82

Because it is a sexually transmitted infection (STI).

Question 83

What infection typically causes ophthalmia neonatorum on days 5–7, and what is the treatment?

Answer 83

Herpes simplex virus; treat with acyclovir ointment.

Question 84

What infection typically causes ophthalmia neonatorum on days 5–14, and what is the treatment?

Answer 84

Chlamydia; treat with erythromycin.