Paediatrics/Strabismus

Question 1

What is the difference between a manifest and latent strabismus?

Answer 1

A manifest squint is one which always present (tropia), a latent squint only appears in certain circumstances (phoria)

Question 2

What is amblyopia and why is it significant in strabismus?

Answer 2

Ambylopia occurs when connects between the eye and visual cortex are not properly connected in early childhood. The most common cause of amblyopia is strabismus.

Question 3

Which are the key exams to undertake for a patient presenting with strabismus?

Answer 3

Check symmetrical corneal reflection
Cover test (manifest squint)
Uncover test (latent squint)
Alternating cover test (disturbs fusion-reveals manifest and latent)
Bruckner Test (observe both red reflexes simultaneously)

Question 4

What is the difference between incomitant and concomitant strabismus?

Answer 4

Incomitant: varies with head posture
Concomitant: does not vary with head posture

Question 5

Describe the diagnosis and management of a refractive esotropia?

Answer 5

Refractive esotropia presents age 3-5
Strongly associated with hypermetropia
Check visual acuity
Wearing glasses may correct squint and hypermetropia

Question 6

Describe the diagnosis and management of congenital esotropia?

Answer 6

Congenital esotropia presents in small infants and carries a high risk of amblyopia. There is usually no refractive error. Corrective surgery is therefore carried out in the child’s second year.

Question 7

What is the most common cause of abnormal head posture?

Answer 7

6th nerve palsy causing ipsilateral weakness of lateral rectus

Question 8

How do you tell the difference between transient strabismus of infancy and congenital esotropia?

Answer 8

Transient strabismus of infancy has no specific direction and comes and goes. It self correct by 4 months of age
Congenital esotropia is always the same eye, is fixed in one direction and will not improve without intervention

Question 9

What is the most common exotropia?

Answer 9

Intermittent exotropia- linked with myopia. Often improves with age so usually managed fine with glasses

Question 10

Describe the features of a third nerve palsy?

Answer 10

Ptosis, down and out, wide fixed pupil

Question 11

Describe the features of a 4th nerve palsy?

Answer 11

Hypertropia (upward gazing pupil), increases in gaze to contralateral side, and increases when head is tilted to ipsilateral side. Most common cause of vertical palsy. Patients often complain of diplopia when looking down

Question 12

What is internuclear ophthalmoplegia?

Answer 12

A disorder of lateral gaze caused by a disruption in the medial longitudinal bundle. It causes defective adduction; the affected eye adducts minimally and causes the unaffected eye to nystagmus

Question 13

What are some other causes of vertical strabismus?

Answer 13

Orbital fracture

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