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.
Which finding is most characteristic of infantile (congenital) esotropia?