ABO Pediatric Ophthalmology & Strabismus 2 — Questions and Answers
Question 1: Which finding is most characteristic of infantile (congenital) esotropia?
- Esotropia fully corrected by hyperopic spectacles
- Small-angle intermittent esotropia beginning at age 3
- Esotropia greater at near only with normal distance alignment
- Large-angle constant esotropia with onset before 6 months of age (Correct answer)
Correct answer: Large-angle constant esotropia with onset before 6 months of age
Infantile esotropia presents before 6 months as a large, stable angle, often with cross-fixation and minimal hyperopia.
Question 2: A 2.5-year-old develops intermittent esotropia that becomes constant; cycloplegic refraction shows +4.00 D OU. What is the initial treatment?
- Base-in prisms only
- Botulinum toxin injection to the medial recti
- Full cycloplegic hyperopic correction (Correct answer)
- Bilateral medial rectus recession
Correct answer: Full cycloplegic hyperopic correction
Refractive accommodative esotropia is treated first with full hyperopic correction.
Question 3: A child with accommodative esotropia is straight at distance with full hyperopic glasses but has 20 PD esotropia at near. Which is the most appropriate next step?
- Reduce the hyperopic correction by 2 D
- Begin occlusion therapy of the dominant eye
- Perform lateral rectus resection
- Prescribe bifocal add (executive or flat-top) of about +2.50 to +3.00 D (Correct answer)
Correct answer: Prescribe bifocal add (executive or flat-top) of about +2.50 to +3.00 D
A high AC/A ratio with residual near esotropia is managed with bifocals that relax accommodation at near.
Question 4: Which feature best describes Duane retraction syndrome type 1?
- Limited adduction with normal abduction and no retraction
- Limited elevation in adduction with a positive forced duction test
- Limited abduction with globe retraction and palpebral fissure narrowing on adduction (Correct answer)
- Limited depression in abduction with a chin-up posture
Correct answer: Limited abduction with globe retraction and palpebral fissure narrowing on adduction
Type 1 Duane, the most common form, shows deficient abduction with retraction on adduction from aberrant CN III innervation of the lateral rectus.
Question 5: A child has limited elevation of the right eye in adduction, a positive forced duction test, and no superior oblique overaction. What is the most likely diagnosis?
- Inferior oblique palsy
- Double elevator palsy
- Right superior oblique palsy
- Brown syndrome (Correct answer)
Correct answer: Brown syndrome
Brown syndrome is a restrictive disorder of the superior oblique tendon-trochlea complex causing a positive forced duction test.
Question 6: In a left superior oblique palsy, the left hypertropia is expected to increase with which maneuver?
- Head tilt to the right shoulder
- Chin-down posture with upgaze
- Gaze to the left
- Head tilt to the left shoulder (Correct answer)
Correct answer: Head tilt to the left shoulder
Ipsilateral head tilt recruits the superior rectus without the superior oblique's depressing action, worsening the hypertropia (Bielschowsky test).
Question 7: Congenital nasolacrimal duct obstruction is most commonly caused by an imperforate membrane at which location?
- Common canaliculus
- Valve of Rosenmüller
- Valve of Hasner (Correct answer)
- Lacrimal punctum
Correct answer: Valve of Hasner
The distal membrane at the valve of Hasner in the inferior meatus is the usual site, and most cases resolve spontaneously by age 1.
