Q: What causes spots and “fireworks” in an eye?
A: The spots and floaters, as we generally refer to them, may be associated with migraines. But they are usually caused by a shrinkage of the jelly that fills the back two-thirds of the eye. As this jelly (vitreous) shrinks two things occur. As light goes through the shrunken jelly, a shadow is formed on the back of the eye. This is what is commonly perceived as a floater. Secondly, as the jelly shrinks, it can pull or tug on the retina causing flashing lights. A thorough evaluation by your family optometrist including a dilated examination is suggested. This examination rules out any serious conditions that also can cause spots and floaters.
Q: When someone says that you have 20/200 vision, is that very bad or very good? In other words, is it what you see at 20 feet, they see at 200 ft or vice versa?
A: This is a common question. 20/200 vision although significantly less than the standard 20/20, is not that bad. It is moderate. 20/200 vision is certainly reduced enough that it should be corrected with glasses or contacts. This may also depend on the patient’s visual needs, but most people would feel that this is blurry (poor) vision if uncorrected. The 20/200 visual measurement means that at 20 feet away you see a size 200 letter. The first number is the distance away that the vision is checked and the second number is the size of the letter that you can read. The larger the number the larger the letter size. If you are 20/200, it means that what you see at 20 ft. is what a person 20/20 can see at 200 ft.
Q: What, if any, treatment is available for lazy eye (amblyopia)?
A: Corrective lenses, prisms and/or contact lenses are often used to treat lazy eye, or amblyopia. Covering or occluding the better eye, for periods during the day, may be used to stimulate vision in the amblyopic eye. In addition, a program of vision therapy may be prescribed to help improve vision function.
Q: What is an astigmatism?
A: Astigmatism is a vision condition in which light entering the eye is unable to be brought to a single focus, resulting in vision being blurred at all distances. Astigmatism is not a disease, but rather, a vision condition that is quite common. It often occurs in conjunction with other refractive errors like nearsightedness and farsightedness.
Q: What causes crossed-eyes?
A: Coordination of your eyes and their ability to work together as a team develops in early childhood. Failure of your eyes (or more precisely, your eye muscles) to coordinate together properly can lead to crossed-eyes. Excessive eye focusing effort in children who are farsighted can also result in crossed-eyes. Crossed-eyes also have a tendency to be hereditary.
Q: What is nearsightedness?
A: Nearsightedness (myopia) is a vision condition in which you can usually see close or near objects clearly, but cannot see distant ones as clearly.
Q: What is farsightedness?
A: Farsightedness (hyperopia) is a vision condition in which distant objects are usually seen clearly, but close ones appear blurred.
Q: What is presbyopia?
A: Presbyopia is an aging vision condition in which the crystalline lens of your eye loses its flexibility. This results in progressive difficulty in focusing on close objects. Your eye stops growing in your early teens. The lens, however, continues to grow and produce more and more cells. This continued growth eventually causes the lens to harden and lose some of its elasticity and therefore some focusing ability.
Q: What is color deficiency?
A: Color deficiency occurs when your ability to distinguish certain colors and shades is less than normal. The term “color blind” is often used, but usually incorrectly. Only a very small number of people are completely unable to identify any colors. There are two major types. Red-green deficiency is by far the most common and results in the inability to distinguish certain shades of red and green. Blue-yellow deficiency is less common and affects the perception of blue and yellow colors. In very rare cases, color deficiency exists to an extent that no colors can be detected. This person sees all things in shades of black, white and gray.
Q: Up to what age can strabismus be treated?
A: Generally, the earlier that strabismus is treated, the better the outcome. Strabismus is treatable at any age. You should speak with your eye care doctor to determine which treatments-glasses, vision therapy and/or surgery–if surgery would be most effective in your case.
Q: I sit in front of a computer screen all day. Can this affect my eyesight in any way? What can I do to prevent possible problems?
A: Many individuals who work at a computer experience eye-related discomfort and/or visual problems. However, based on current evidence it is unlikely that the use of computers causes permanent changes or damage to the eyes or visual system. Many of the potential eye and/or vision problems relating to computer use can be reduced or eliminated by appropriate adjustment and placement of the computer, proper workplace design and lighting control, good preventive vision care habits and regular professional eye care.