Astigmatism is a common eye condition that affects the way light enters the eye, causing blurred or distorted vision. It occurs when the cornea (the clear front surface of the eye) or the lens inside the eye has an irregular shape. Instead of being round or spherical like a basketball, the cornea or lens may resemble the shape of a football or an egg. This irregular shape prevents light from focusing properly on the retina, leading to blurry or fuzzy vision.
What causes astigmatism?
Astigmatism can occur due to both genetic and environmental factors. Some individuals are born with astigmatism, while others may develop it later in life. The exact cause is not always clear, but it is often related to the shape of the cornea. Certain conditions, such as keratoconus (a progressive thinning of the cornea), injury or surgery to the eye, and certain types of eye inflammation, can also contribute to the development of astigmatism.
What are the symptoms of astigmatism?
Common symptoms of astigmatism include blurred or distorted vision at all distances, eyestrain, headaches, difficulty seeing fine details, and squinting. People with astigmatism often experience both nearsightedness and farsightedness simultaneously, as the irregular cornea shape affects the way light focuses on the retina.
How is astigmatism diagnosed?
An eye care professional can diagnose astigmatism through a comprehensive eye examination. The examination may include tests such as a visual acuity test (to measure how well you see at various distances), a keratometry test (to measure the curvature of the cornea), and a refraction test (to determine the exact prescription for corrective lenses). These tests help assess the presence and severity of astigmatism and guide the appropriate treatment.
How is astigmatism treated?
Astigmatism can be corrected using eyeglasses, contact lenses, or refractive surgery. Eyeglasses and contact lenses work by compensating for the irregular shape of the cornea, allowing light to focus correctly on the retina. Refractive surgery, such as LASIK or PRK, can permanently change the shape of the cornea to correct astigmatism. The choice of treatment depends on factors such as the severity of astigmatism, lifestyle, and