Strabismus and ocular motility disorders — formative SAQs

SAQ 1 (10)

A three-year-old is brought in because the right eye has been turning inward over the past three months. The parents describe a turn that was intermittent at first but is now present most of the time, worse when the child is tired. The cover-uncover test shows a right esotropia, and the angle is the same when the child looks to the left, to the right and at near. The alternate-cover test measures a slightly larger deviation. Visual acuity is reduced in the right eye. ^{[1] [5]}

a) What is the most likely diagnosis, which single investigation is most important, and how does its result guide the first treatment? (3 marks) ^{[5] [2]}

b) Outline the fixed sequence of definitive management, naming each step and explaining why the order matters for binocular vision. (3 marks) ^{[1] [11]}

c) The right eye has reduced acuity. State the two main amblyopia treatment options, how they compare for moderate amblyopia, and the principle that governs their timing relative to surgery. (2 marks) ^{[9] [11]}

d) Explain why a high accommodative convergence to accommodation ratio subtype might require a bifocal add, and how it differs from the purely refractive subtype. (2 marks) ^[5]