näkövirhettä

Näkövirhettä, or refractive error, is a common vision condition where the eye does not focus light correctly on the retina. This results in blurry or distorted vision. The primary types of refractive errors are myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia. Myopia occurs when the eyeball is too long or the cornea is too curved, causing distant objects to appear blurry. Hyperopia happens when the eyeball is too short or the cornea is too flat, making near objects blurry, though in severe cases, distant objects can also be affected. Astigmatism is caused by an irregularly shaped cornea or lens, leading to blurry vision at all distances. Presbyopia is an age-related condition where the lens of the eye loses its flexibility, making it difficult to focus on close objects.

Refractive errors are typically diagnosed through a comprehensive eye examination conducted by an optometrist or ophthalmologist. Symptoms can include squinting, eye strain, headaches, and difficulty seeing clearly at specific distances. The exact cause of refractive errors is not always known, but genetics and environmental factors are believed to play a role.

Treatment for näkövirhettä aims to correct the way light focuses on the retina. The most common methods include prescription eyeglasses and contact lenses, which bend light to compensate for the eye's focusing issue. Refractive surgery, such as LASIK or PRK, is another option for some individuals, permanently altering the shape of the cornea to correct the refractive error. Early detection and appropriate correction are important for maintaining good vision and preventing potential complications.