Glasses are a common and effective solution for correcting astigmatism. These specialized corrective lenses are designed to address the unique visual challenges posed by this refractive error. When properly prescribed, glasses can significantly improve visual acuity and reduce associated symptoms, making daily activities more comfortable.
What Astigmatism Is
Astigmatism is a common condition characterized by an imperfection in the curvature of the eye’s cornea or lens. Instead of having a perfectly round, spherical shape, the affected part of the eye is shaped more like an American football or an egg. This irregular curvature means that light entering the eye does not bend uniformly.
Due to this uneven bending, light rays fail to focus on a single point on the retina, the light-sensitive layer at the back of the eye. Consequently, vision becomes blurry or distorted at all distances. This can lead to symptoms such as eyestrain, headaches, and difficulty seeing fine details.
Astigmatism is classified as a refractive error and often occurs alongside other common vision conditions such as nearsightedness (myopia) or farsightedness (hyperopia). It is frequently present at birth, though its severity can change over time.
How Glasses Correct Vision
Glasses for astigmatism use specialized “toric” or “cylindrical” lenses. Unlike standard spherical lenses, these unique lenses have different curvatures in different meridians. This design compensates for the eye’s irregular shape.
The varying curvatures of a cylindrical lens bend light differently along specific axes. This ensures all incoming light rays focus correctly onto a single point on the retina. By refocusing light, the lenses sharpen vision and reduce distortion.
An eyeglass prescription for astigmatism includes specific values for correction. The “cylinder” value indicates the lens power needed to correct the irregular shape. The “axis” value specifies the exact orientation where this corrective power applies on the lens.
These two values work together to create a lens that customizes light bending to match the individual irregularities of each eye. Without a properly defined axis, the cylinder correction would not align correctly, leaving the astigmatism unaddressed. This detailed prescription ensures light is refracted precisely, allowing for clear vision.
Obtaining Astigmatism Glasses
Obtaining glasses for astigmatism begins with a comprehensive eye examination by an eye care professional. During this exam, tests diagnose astigmatism and determine the precise prescription. A refraction test, for example, involves looking through various lenses to identify the clearest vision.
The eye care professional may also use instruments like a keratometer or corneal topography to measure the curvature of the cornea. The precision of this prescription is important, as even small misalignments can affect visual clarity.
Once the precise prescription is determined, glasses are manufactured with the necessary cylindrical lenses. When first wearing new astigmatism glasses, individuals might experience a brief adjustment period. This period, lasting from a few days up to two weeks, allows the brain to adapt to the new way of processing images.
During this time, some people may notice slight distortions, such as tilted floors or walls. This typically resolves as the brain acclimates. Continued wear during this adjustment phase is recommended to help the eyes and brain adapt. If discomfort or blurriness persists beyond two weeks, consult the eye care professional.