8.1.2. Understands the management of a patient with an anomaly of binocular vision

Question 1

Can you explain the different types of amblyopia and their causes?

Answer 1

Amblyopia can be classified into stimulus deprivation, strabismic, and anisometropic amblyopia. Stimulus deprivation occurs when no light or form reaches the retina, strabismic amblyopia is caused by suppression due to strabismus, and anisometropic amblyopia results from unequal refractive errors between the eyes.

Question 2

What is the critical period in visual development, and why is it important in amblyopia?

Answer 2

The critical period is the time during early childhood when the visual system is most plastic and responsive to stimuli. Treating amblyopia during this period is crucial because the brain is still developing its visual pathways, and treatment is most effective.

Question 3

How would you manage a child with newly diagnosed strabismic amblyopia?

Answer 3

Full refractive correction with glasses, followed by occlusion therapy of the better eye, or penalisation therapy with atropine to encourage the use of the amblyopic eye. The prognosis depends on factors such as age and initial visual acuity.

Question 4

When should you refer a patient with amblyopia, and why?

Answer 4

Referral is necessary if there is no improvement after full correction and occlusion therapy, or if there is an underlying condition like cataract or ptosis. Also, refer if the amblyopia is accompanied by neurological signs or suspected pathology.

Question 5

How does anisometropia lead to amblyopia, and what is the first-line treatment?

Answer 5

Anisometropia creates a significant difference in image clarity between the two eyes, leading to suppression in the weaker eye. The first-line treatment is full refractive correction with glasses.

Question 6

How do you determine the appropriate amount of occlusion therapy for a patient?

Answer 6

Based on visual acuity. For VA 6/9-6/24, 2 hours of patching daily is recommended, while for VA worse than 6/24, 6 hours of patching daily is needed.

Question 7

What would you do if a patient has failed to comply with amblyopia therapy?

Answer 7

Consider switching to optical penalisation using atropine or lenses if the patient cannot tolerate patching. Monitor compliance closely and engage with the family for better adherence.

Question 8

Explain the differences between penalisation therapy using atropine and occlusion therapy.

Answer 8

Penalisation blurs the vision in the better eye using atropine drops or lenses, encouraging use of the amblyopic eye. Occlusion therapy involves patching the better eye to force the amblyopic eye to work. Penalisation is cosmetically better but not suitable for severe amblyopia.

Question 9

What are the contraindications to using atropine for penalisation therapy?

Answer 9

Atropine is contraindicated in patients with heart defects, allergies, or sensitivity to the drops.

Question 10

How would you approach a case where there is a discrepancy between the two eyes in refractive error (>1.50D)?

Answer 10

Prescribe full refractive correction and follow up in 3 months to assess improvement. Occlusion therapy may not be necessary if vision improves.

Question 11

What steps would you take to assess and correct refractive errors in a child with suspected amblyopia?

Answer 11

Perform retinoscopy to measure refractive error, prescribe full correction, and monitor visual acuity improvements. If no improvement is seen after 16 weeks, initiate occlusion therapy.

Question 12

When would you prescribe prismatic correction, and what is its purpose?

Answer 12

Prism correction is prescribed for small-angle deviations to help align the eyes and improve binocular vision.

Question 13

What factors would influence your decision to refer a patient for strabismus surgery?

Answer 13

Severe strabismus, failure of non-surgical methods like occlusion or orthoptic exercises, and cosmetic concerns. Referral is also necessary if strabismus significantly affects visual function.

Question 14

Can you explain how you would assess visual fields in a patient with amblyopia?

Answer 14

Visual fields can be assessed using confrontation testing or automated perimetry. For children with reduced acuity, use larger or brighter fixation targets and consider alternative techniques like Amsler grid or kinetic perimetry.

Question 15

Describe the orthoptic exercises you would recommend for a patient with convergence insufficiency.

Answer 15

Pencil push-ups: The patient focuses on a pencil as it moves closer to the nose, helping to improve convergence and eye alignment.

Question 16

What are the signs and symptoms of convergence insufficiency, and how does it relate to amblyopia?

Answer 16

Symptoms include eye strain, headaches, and difficulty focusing on near tasks. It can contribute to amblyopia if the patient develops suppression due to difficulty maintaining convergence.

Question 17

Explain how you would assess binocular vision in a child with a suspected phoria or tropia.

Answer 17

Perform cover tests, assess motility, and measure stereoacuity. Binocular function can also be evaluated with the use of Worth 4 Dot or stereoacuity tests like Titmus Fly.

Question 18

How would you explain the treatment options for amblyopia to a parent who is concerned about patching?

Answer 18

Explain that patching encourages the weaker eye to work harder, improving visual acuity. Discuss alternatives like penalisation therapy with atropine and emphasize the importance of early intervention.

Question 19

What considerations would you take into account for managing a child with amblyopia who has multiple disabilities (e.g., Down syndrome)?

Answer 19

Adapt the management plan to accommodate the child’s cognitive and physical abilities. Use simpler techniques, more frequent monitoring, and engage caregivers for better compliance.

Question 20

How do you ensure that a patient adheres to amblyopia therapy, and what steps would you take if they are non-compliant?

Answer 20

Regularly communicate with the family, provide educational resources, and make therapy more manageable by using fun patches or less invasive techniques like penalisation if necessary.

Question 21

What role do you think the optometrist has in preventing and managing amblyopia in children?

Answer 21

Early screening, proper refractive correction, and timely management of amblyopia are crucial. Optometrists play a key role in educating parents and ensuring regular follow-up.

Question 22

What differential diagnoses would you consider for a child presenting with reduced vision and no apparent strabismus or anisometropia?

Answer 22

Consider conditions like congenital cataracts, optic neuropathy, retinal diseases, or neurological conditions affecting the visual pathway.

Question 23

What are the main risk factors for developing amblyopia, and how would you screen for them?

Answer 23

Risk factors include a family history of amblyopia, premature birth, low birth weight, developmental delays, and refractive errors. Screening involves comprehensive eye exams, including visual acuity and binocular vision assessment.

Question 24

If a patient’s amblyopia does not improve after treatment, what could be the underlying reasons?

Answer 24

Possible reasons include poor compliance, incorrect refractive correction, underlying ocular pathology, or insufficient duration of treatment.

Question 25

How would you record and monitor visual acuity improvements during amblyopia treatment?

Answer 25

Document visual acuity at each visit, note any changes in refractive correction, compliance with therapy, and improvement in visual function. Use charts like LogMAR to track progress accurately.