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What does “refractive error in the left and right eyes” mean?

Mar 04, 2022 Source: Cainiu Health
Dr. Cui Xin
Introduction
Myopia refers to a condition in which, with the ciliary muscle relaxed, parallel light rays are focused by the eye’s refractive system in front of the retina. It may result from genetic factors or from prolonged near work—such as extended computer or smartphone use—that leads to excessive eye fatigue. Myopia commonly causes decreased visual acuity and blurred vision, and may also lead to anisometropia (unequal refractive error between the two eyes). Patients can correct myopia with eyeglasses.

“Refractive error in both eyes” refers to a condition where, with the eye’s accommodation relaxed, parallel light rays from the external environment fail to focus precisely on the fovea centralis of the retina, resulting in blurred or unclear vision. This phenomenon may arise from various causes, including myopia (nearsightedness), hyperopia (farsightedness), and astigmatism.

What does “refractive error in both eyes” mean?

1. Myopia: In myopia, with accommodation relaxed, parallel light rays entering the eye are focused anterior to the retina after passing through the eye’s refractive system. This condition may result from genetic factors or prolonged near work—such as extended computer or smartphone use—that leads to excessive ocular fatigue. Myopia typically causes decreased visual acuity and blurred vision, especially for distant objects, and may contribute to refractive errors in both eyes. Correction options include wearing spectacles or contact lenses. Surgical treatments include laser in situ keratomileusis (LASIK) and photorefractive keratectomy (PRK).

2. Hyperopia: In hyperopia, parallel light rays entering the eye are focused posterior to the retina after refraction by the eye’s optical media, resulting in blurred near vision. Hyperopia can impair both distance and near vision, cause accommodative fatigue, and—in severe cases—lead to strabismus or amblyopia. It may also contribute to bilateral refractive error. Correction is commonly achieved with spectacles or contact lenses. Refractive surgery options include LASIK.

3. Astigmatism: Astigmatism is a type of refractive error associated with irregular corneal curvature. It often leads to reduced visual acuity, strabismus, and amblyopia, thereby interfering with daily activities and work performance. Optical correction is typically achieved using cylindrical lenses (toric lenses). For severe cases, surgical interventions such as laser thermal keratoplasty or corneal incisional surgery may be considered.

Avoid prolonged use of computers or smartphones to prevent exacerbation of ocular discomfort.

We hope the above information is helpful to you. Wishing you good health and happiness!

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