Anisometropia myopia as an amblyogenic factor is characterized as a difference greater than how many diopters between the two eyes?

• A. -4.00D
• B. -3.00D
• C. -2.00D
• D. -5.00D

Answer: (B)

A large difference in refractive error between the eyes disrupts binocular development because the brain tends to rely on the clearer image and suppresses the blurrier eye. Over time, this suppression can lead to amblyopia in the more myopic eye.

For myopia, the level at which this risk becomes clinically significant is about a 3 diopter interocular difference. That means when one eye is more than 3 diopters different from the other, the anisometropia is considered amblyogenic. Smaller differences are less likely to produce amblyopia, while larger differences indicate higher risk, though treatment decisions depend on the individual’s age and visual development.

So the threshold to identify amblyogenic anisometropia in myopia is a difference greater than 3 diopters.