What condition is represented by the following prescription: OD -1.25 OS -4.25?

The prescription given indicates different refractive errors for each eye, specifically -1.25 diopters for the right eye (OD) and -4.25 diopters for the left eye (OS). This means that the left eye requires a stronger lens correction compared to the right eye.

Anisometropia refers to a condition where there is a significant difference in refractive power between the two eyes, which can lead to challenges in binocular vision and depth perception. In this case, the disparity of 3.00 diopters between the two eyes clearly characterizes anisometropia.

The other options do not fit this scenario: myopia refers to nearsightedness typically represented by a negative prescription, but it does not specifically address the difference between eyes; hyperopia involves a positive prescription indicating far-sightedness; and astigmatism is characterized by an irregular curvature of the cornea or lens and does not pertain to the difference in refractive strength between the two eyes.

Thus, the correct answer highlights the significant difference in prescription strength, marking this condition as anisometropia.