Presbyopia

Presbyopia is a vision condition in which the crystalline lens of the eye loses its flexibility, that makes it difficult to focus on close objects.
The loss of flexibility takes place over a number of years. Presbyopia usually becomes noticeable in the early to mid-40's. Presbyopia is a natural part of the aging process of the eye. It is not a disease, and it cannot be prevented.

Symptoms of presbyopia include the tendency to hold reading materials at arm's length, blurred vision at normal reading distance and eye fatigue. 
To help you compensate for presbyopia, your optometrist can prescribe reading glasses, bifocals or contact lenses.

Astigmatism

Astigmatism is a vision condition that causes blurred vision due irregular shape of  cornea or the  curvature of the eye lens. An irregular shaped cornea or lens prevents light from focusing properly on the retina. As a result, vision becomes blurred at any distance. Astigmatism is a very common vision condition. Most people have some degree of astigmatism. Slight amounts of astigmatism usually don't affect vision and don't require any treatment. However, larger amounts cause distorted or blurred vision, eye discomfort and headaches.

Astigmatism frequently occurs with other vision conditions like nearsightedness (myopia) and farsightedness (hyperopia). Together these vision conditions are referred to as refractive errors because they affect how the eyes bend or "refract" light.

Persons with astigmatism have several options available to regain clear vision. They include:

• eyeglasses
• contact lenses
• laser and other refractive surgery procedures

Eyeglasses are the primary choice of correction for persons with astigmatism. They will contain a special cylindrical lens prescription to compensate for the astigmatism. An example of a prescription for astigmatism for one eye would be -1.00 -1.25 X 180. The middle number (-1.25) is the lens power for correction of the astigmatism. The "X 180" designates the placement (axis) of the lens power. The first number (-1.00) indicates that this prescription also includes a correction for nearsightedness in addition to astigmatism.