Common Vision Problems and Causes
is the ability of the eye to focus on items and tasks
that are farther away, but inability to focus on items
and tasks that are closer to the eye. This condition
occurs when light entering the eyeball through the
cornea does not focus correctly on the back of the
eye. Rather the point where the light should come to a
focus occurs beyond the back of the eyeball. This
occurs because the cornea has too little curvature to
adjust the light, or because the eyeball is shorter
than in those without Hyperopia.
Unlike Nearsightedness (Myopia), Hyperopia is usually not diagnosed in school-aged children, and standard vision screening does not often find this problem.
If you have the symptoms of Hyperopia, like difficulty keeping focus on tasks that are close to the eye, headaches after close work or reading, or eye strain and fatigue after focusing on close projects, see your eye care professional. Only your eye care professional can diagnose this or any eye ailment.
Your eye care professional will discuss your options for vision correction. This may include glasses, or a contact lens prescription to correct your vision problems.
or Myopia occurs in a large percentage of the
population. It is usually diagnosed in school-aged
children when they have difficulty seeing the
chalkboard. Myopia occurs in people with a longer
eyeball than normal, or those with greater curvature
to the cornea of the eye. The light entering the eye
then focuses closer to the front of the eye. This
means that objects and tasks that are farther away may
There is evidence to support the theory that Myopia is partially hereditary. There is also some evidence that Myopia is a stress related condition caused by too much eye strain and close eye work. Myopia is usually fully developed and diagnosed by age 20, as the eye continues to grow and problems become more apparent throughout childhood.
Only your optometrist can diagnose Myopia. Your optometrist can prescribe eyeglasses or contact lenses that will correct Myopia by altering the way light enters your eye by changing the curvature of the cornea. Your eyeglasses or contact lenses may be worn for certain activities, like driving, or may be worn all the time. Another option for Myopia patients is orthokeratology, a process that reshapes the cornea through a series of non-invasive contact lens therapies.
occurs when the cornea of the eye is shaped
irregularly, more like a football than a baseball.
Because of this cornea shape, light does not focus
correctly on the back of the eye. Astigmatism can
affect your vision by blurring objects and tasks
placed at all distances. Patients with Astigmatism
often see skewed images. Astigmatism can be
accompanied by Myopia (nearsightedness) or Hyperopia
Most people have some degree of Astigmatism, or deviation in the shape of the cornea. Many people with Astigmatism believe that they cannot wear contact lenses. However, most patients can benefit from properly fitted Toric contact lenses. These lenses are shaped with more than one power in the lens to correct the Astigmatism. These lenses are also stabilized on the eye to prevent the lens from rotating as spherical lenses do.
Sufferers of slight Astigmatism may also be candidates for aspherical lenses. These lenses have a slightly different shape than regular spherical lenses. If you suspect you have Astigmatism, see your eye care professional. Only an eye care professional can diagnose problems associated with vision.
Many people with Astigmatism believe they can't wear contact lenses, or that only rigid contact lenses can correct Astigmatism-but this is no longer true. Now there are soft lens designs, which correct Astigmatism, and these are called toric contact lenses. Toric lenses have a special correction built into them, and may also contain a prescription for nearsightedness or farsightedness.
Presbyopia is a
condition that occurs as part of the natural aging
process of the eye, where the lens becomes more rigid
and difficult to focus. In patients with Presbyopia,
reading and other tasks become difficult at the
regular distance from the eye. The material may need
to be moved farther away from the eye to be seen
clearly. This condition is usually corrected with
reading or bifocal eyeglasses.
Eyeglasses are not the only way to treat Presbyopia. Bifocal contact lenses that combine two or strengths in one lens are also an option. These contact lenses use approximately half the area of the lens to correct the Presbyopia, and the top half of the lens can be used to treat other vision problems like Hyperopia (farsightedness).