Vision & Cataracts at Alabama Eye & Cataract Center at UAB Highlands in Birmingham, AL

Cataracts & Vision
Understanding that your eyes are a living, complex optical system helps you to learn about vision problems, presbyopia and cataracts. In order to have good vision it is necessary to have to healthy structures in and around the eye as well as the proper “optical” functioning of each structure.  There are a number of common “optical” or “focusing” problems that can blur your vision. These include refractive problems such as myopia or nearsightedness, hyperopia or farsightedness, astigmatism and presbyopia.

Myopia or Nearsightedness

Myopia, more commonly referred to as nearsightedness, is the most common refractive condition and affects one in four people in North America. Myopia allows people to see near objects clearly, but causes distant objects to be blurry. Myopia occurs when light rays entering the eye are focused in front of the Retina instead of directly on it. Myopia is usually a result of the curvature or power of the Cornea being too strong or the length of the eyeball being too long.

Hyperopia or Farsightedness

Hyperopia, or farsightedness, occurs when people see far away objects more clearly than those that are up close. Hyperopia is caused when light rays are not focused by the time they reach the Retina. Hyperopia is usually a result of the curvature or power of the cornea being too weak or the length of the eyeball being too short.


Astigmatism is the result of having a corneal surface that is not regular in shape. The eye is unable to focus clearly at any distance because of this irregular focusing surface. Individuals with no astigmatism have corneas that are round and shaped like basketballs, while individuals with astigmatism have corneas that are shaped more like footballs. There are a number of possible types of astigmatic corneas, which is why your eyes must be examined in order to determine the degree and type of astigmatism. People with astigmatism may also be myopic or hyperopic.

Keep in mind that seeing “normally” and having clear vision requires not only that light “focuses” properly, but that light be able to efficiently pass through the optical structures of your eyes. The two primary structures that are responsible for refracting, or bending light so that it can focus properly on the back of the eye-or the retina-are the cornea, which is the outermost clear curved “lens” that is visible when looking at your eye from a side view and the crystalline lens, which is located behind the colored part of the eye, or the iris, and is not directly visible. The crystalline lens will be examined during your eye examination by using specialized instruments to look through the pupil, or the dark center of the iris. Both the cornea and the crystalline lens need to be perfectly clear in order for you to have good vision. If you are in good health and have not had chronic eye infections, inflammation or had any trauma to your eyes, the cornea is likely to maintain its clarity throughout your life. The crystalline lens however undergoes a number of changes that progress as we age. These aging changes can affect your vision.

Usually by about the time we reach the age of 40 years old, most of us begin to experience some of the visual effects that result from changes in the crystalline lens. Even if you have had “good eyes” and “normal vision” all your life, your vision is likely to begin to change in a number of ways. As we progress from our 40’s, to our 50’s and then our 60’s and beyond, the most obvious changes to our vision occur as a result of these changes in the crystalline lens.
The two most common changes that occur in the Crystalline Lens are:

  • A loss of flexibility, called presbyopia, which makes it harder to read and
  • A loss of optical clarity, which can cause a cataract.

Development & Symptoms of a Cataract
When we are younger, the crystalline lens is usually soft, flexible and “crystal” clear so that it has excellent transparency and optical clarity. As we progress through our 50’s and 60’s, the normally “crystal” clear lens may gradually become yellow and cloudy. When this occurs, you may initially experience a mild blurring of your vision and feel that you might need a change of eyeglasses. As the crystalline lens loses its transparency and its optical clarity, you may notice that it is not as easy to see well and comfortably in dim illumination, such as for night driving. You may notice that colors look faded. The cloudiness may also create glare, haloes, light sensitivity and a continuing decrease in your vision. If the crystalline Lens becomes too cloudy it may cause a significant decrease in both your day and night vision. These are the visual symptoms that are common for those patients whose crystalline lens has clouded and formed a cataract.

As we get older, cataracts often become a common eye problem experienced by a great number of people just like you. Cataracts can affect us even if we have had normal vision all of our lives. It is important to note that cataracts are even more common if we have had certain health problems such as diabetes or taken certain medications such as cortisone for asthma or other types of inflammatory conditions. If you are experiencing vision changes like these, it is important to schedule a comprehensive eye examination and cataract evaluation.

About Presbyopia & Near Vision
Presbyopia is an aging phenomenon that begins at around age 40 and progresses until about age 65 as the crystalline lens loses its flexibility. This flexibility allows the crystalline lens to change its shape and alter its curvature in order to rapidly focus your vision at various distances-from far, to near, to arms length, to far or near again. The focusing capacity of the crystalline lens gives you the ability to see things at all distances.

Around the time we enter our 40’s, the crystalline lens begins to stiffen. The stiffening of the crystalline lens makes it progressively more difficult to change focus from distance to near, and thus making it more difficult to see close up. Initially, this reduces our ability to see objects clearly at arm’s length. As presbyopia progresses it becomes more difficult to see reading material or objects close up.

As patients begin to experience presbyopia they often notice that their "arms are too short" requiring them to see up close by moving near objects and reading material farther away in order to bring them into focus and to see them clearly. It is important to know that presbyopia affects everyone including those who have cataracts. As Presbyopia begins, people who have never worn eyeglasses find that they need reading glasses or bifocals in order to read and see up close. People who already wear glasses may need bifocals or trifocals in order to see up close and have comfortable near vision.

Advances in cataract surgery and lens implants allow us to correct nearsightedness, farsightedness and astigmatism-as well as the near vision focusing problem-presbyopia-with advanced technology lens implants. Near vision presbyopia correcting lens implants allow us to correct distance, arm’s length and near vision to help patients achieve clear distance vision as well restore their normal range of vision without relying on eyeglasses, bifocals or reading glasses. At Alabama Eye & Cataract Center in Birmingham we offer near vision correction lens implants such as the Tecnis® Multifocal Lens Implant (IOL), the AcrySof® ReSTOR® Multifocal Lens Implant (IOL) and the Crystalens® Accommodating Lens Implant as well as lens implants for astigmatism such as the AcrySof® Toric Lens Implant and the Tecnis® Toric Lens Implants

To learn more about cataracts, vision changes with a cataract, symptoms of cataracts or near vision focusing problems such as presbyopia, please schedule an appointment for a cataract consultation at Alabama Eye & Cataract Center by calling us at 205-930-0930.