Astigmatism is a common vision condition affecting how light focuses on the retina, leading to blurred or distorted vision. While many assume vision problems are static, astigmatism can change over time, with its severity potentially increasing or decreasing. Regular monitoring of eye health is helpful for maintaining clear vision.
Understanding Astigmatism
Astigmatism arises from an imperfection in the curvature of the eye’s cornea, the clear front surface, or the lens inside the eye. Instead of a uniformly round shape like a basketball, the affected surface is more oblong or egg-shaped. This irregular curvature prevents light rays from bending evenly as they enter the eye.
When light does not refract properly, it focuses at multiple points on the retina rather than a single sharp point. This results in blurry or distorted vision at all distances. Astigmatism can occur alongside other common refractive errors like nearsightedness (myopia) or farsightedness (hyperopia).
Factors Influencing Astigmatism Variation
Astigmatism can fluctuate due to several factors, both natural and from specific conditions or interventions. These changes can manifest at different stages of life.
Age-related changes are a common reason for shifts. Astigmatism can develop or change during childhood and often stabilizes in early adulthood. As people age, typically after 40, the eye’s natural lens can become less flexible, and the cornea’s shape may gradually alter, contributing to new or worsening astigmatism.
Certain eye conditions can significantly influence astigmatism. Keratoconus, a progressive disorder, causes the cornea to thin and bulge into a cone shape, leading to increasing and often irregular astigmatism that standard glasses cannot fully correct. Cataracts, which involve the clouding of the eye’s natural lens, can also induce or worsen astigmatism as the lens becomes misshapen.
Eye surgeries also play a role. Refractive procedures like LASIK and PRK aim to reshape the cornea to correct existing astigmatism. These surgeries can sometimes induce new astigmatism or result in residual astigmatism. Cataract surgery, while removing the clouded lens, can also alter corneal shape, potentially changing astigmatism.
Direct trauma or injury to the eye can alter the cornea’s shape, leading to new or changed astigmatism. Temporary factors like excessive eyelid pressure can affect corneal curvature. Hormonal fluctuations during puberty, pregnancy, or menopause can also lead to temporary changes in vision, including subtle alterations in corneal shape.
Implications of Astigmatism Changes
When astigmatism changes, individuals may notice several signs. Common symptoms include worsening blurriness or distortion, increased eye strain, and persistent headaches. Difficulty seeing clearly at night, often accompanied by glare or halos around lights, is another frequent complaint.
Regular eye examinations are important for monitoring vision and detecting these changes early. Eye care professionals can identify subtle shifts in astigmatism and adjust corrective measures. If changes are detected, the most common approach is to update prescriptions for corrective lenses, such as glasses or contact lenses, to restore clear vision.
Significant or rapid changes in astigmatism warrant further investigation by an eye care professional. Such shifts could indicate an underlying eye condition that requires specific management. Addressing these changes promptly ensures vision remains clear and comfortable.