Hyperopia is better known as farsightedness; Myopia is better known as nearsightedness. In these refractive errors, the eye is not shaped/sized to properly compliment its focusing power (light doesn't focus directly on the back of the eye as it should), resulting in blurry vision up close (hyperopia) or at a distance (myopia). Young children typically have some degree of refractive error (more commonly hyperopia), so these numbers change as the child’s age increases and the acuity a child their age would be expected to have improves. The higher the number, the more significant the deficiency. (+) numbers indicate hyperopia; (-), myopia.
Anisometropia is a significant difference in the power of the eyes. The screener uses the spherical equivalent measurement to calculate whether one eye is significantly stronger than the other. If the difference in the two spherical equivalent measurements is 1.00 D or greater, regardless of age, a referral is generated. A significant difference may indicate the potential for amblyopia, or “lazy eye”.
Astigmatism results in blurry vision because the eyes are not able to sharply focus light. Young children have some degree of astigmatism, measured as “cylinder”, so a referral will not be generated unless this number is equal to or above the number given in the heading. This number changes with age, as the degree of astigmatism that is normal decreases as a child matures.
Astigmatism results in blurry vision because the eyes are not able to sharply focus light. Young children have some degree of astigmatism, measured as “cylinder”, so a referral will not be generated unless this number is equal to or above the number given in the heading. This number changes with age, as the degree of astigmatism that is normal decreases as a child matures.
Refractive error occurs if the eye cannot focus light properly on the retina. It usually causes blurry vision and in most cases can be corrected with eyeglasses (Astigmatism, Hyperopia, Myopia - see below). Some refractive errors, if not corrected early enough, can lead to permanent vision loss in the affected eye (see Anisometropia below). This is known as amblyopia, or “lazy eye”. Amblyopia can result from any condition causing one eye to be significantly stronger than the other; this may include anisometropia, strabismus (see corneal reflex below), opacities, ptosis (drooping eyelids), or other conditions. Early treatment is the key to preventing vision loss from amblyopia.
For more information, please contact Conexus or visit our eye health and safety information library.