COT Ocular Motility Testing 5 — Questions and Answers
Question 1: Brown syndrome is caused by:
- Overaction of the inferior oblique
- Restriction of the superior oblique tendon sheath (Correct answer)
- Paresis of the superior rectus
- Fibrosis of the inferior rectus
Correct answer: Restriction of the superior oblique tendon sheath
Brown syndrome results from a tight or restricted superior oblique tendon sheath, limiting passive and active elevation in adduction.
Question 2: Internuclear ophthalmoplegia (INO) is caused by a lesion in which structure?
- Oculomotor nucleus
- Abducens nucleus
- Medial longitudinal fasciculus (Correct answer)
- Trochlear nucleus
Correct answer: Medial longitudinal fasciculus
INO results from a lesion in the medial longitudinal fasciculus (MLF), disrupting conjugate horizontal gaze coordination between the abducens and contralateral oculomotor nuclei.
Question 3: During near point of convergence (NPC) testing, a receded NPC (beyond 10 cm) is associated with:
- Convergence excess
- Convergence insufficiency (Correct answer)
- Divergence excess
- Basic esophoria
Correct answer: Convergence insufficiency
A receded NPC beyond approximately 6–10 cm is the hallmark objective finding in convergence insufficiency.
Question 4: The Bagolini striated lens test is used to evaluate:
- Pupil responses under monocular conditions
- Binocular status under near-natural conditions (Correct answer)
- Color vision deficiencies
- Accommodative amplitude
Correct answer: Binocular status under near-natural conditions
Bagolini striated lenses minimally disrupt binocular vision, allowing assessment of fusion, suppression, and anomalous retinal correspondence under near-natural viewing conditions.
Question 5: In the prism and alternate cover (PACT) test, what does the total deviation measured represent?
- Only the tropic component of deviation
- Only the phoric component
- The total deviation including both phoria and tropia (Correct answer)
- The fusional vergence amplitude
Correct answer: The total deviation including both phoria and tropia
The PACT disrupts fusion completely, measuring the total deviation which includes both the manifest (tropia) and latent (phoria) components.
Question 6: Positive fusional vergence (PFV) is measured by increasing which type of prism before both eyes?
- Base-in prism
- Base-out prism (Correct answer)
- Base-up prism
- Base-down prism
Correct answer: Base-out prism
PFV is measured by placing increasing base-out prism before both eyes while the patient maintains fusion on a target, stimulating convergence.
Question 7: Strabismus surgery to treat esotropia most commonly involves which procedure?
- Lateral rectus resection and medial rectus recession
- Bilateral medial rectus recession (Correct answer)
- Bilateral lateral rectus resection
- Superior oblique tenotomy
Correct answer: Bilateral medial rectus recession
Bilateral medial rectus recession is the standard surgical approach for comitant esotropia, weakening the overacting adductors.
COT Ocular Motility Testing 5
Brown syndrome is caused by: