In general, removal is easier than insertion. Lenses are removed, not with the fingers but with the lid margins. When you are wearing lenses your lids, on closing, slip easily over the lens to be in front of it. Indeed, for most of the time your upper lids will be covering the upper part of the front surface of the lenses so that when your eyes close, the lids simply slip down over the front surfaces. If however, your lids are held so wide apart that the lid margins are above and below the edge of the lens, and if the lid margins are then pressed tightly against the cornea, any attempt to bring the lids together will tend to squeeze the contact lens off the cornea. Read the rest of this entry »
Q. Will my eyes be continuously red?
A. If they are, something is wrong. Contact the fitter at once.
Q. Can you tell that someone is wearing contact lenses?
A. Usually not.
Q. Can they be coloured?
A. Yes. Lenses can be tinted almost any colour. Read the rest of this entry »
Q. I am short-sighted, 50, and need two pairs of glasses. I can’t bear the thought of bifocal glasses. Is there any alternative? A. Certainly. Contact lenses and reading glasses.,
Q. I am long-sighted, 45, and beginning to have problems reading. Also, my distance vision is sometimes a little blurred. Do you recommend contact lenses?
A. Yes. They should solve all your problems for a number of years. Eventually, of course, you will need reading glasses as well as contact lenses, but you will be spared bifocals. Read the rest of this entry »
A bandage lens, also called a therapeutic lens, is a special soft, very thin, high-water-content contact lens. In 1974 this hydrophilic lens was the first type to be used on an extended-wear basis, but without incorporating a prescription. It has a wide variety of uses before ocular surgery, after ocular surgery, and sometimes instead of surgery. It can also be therapeutic in conditions that do not respond to any other form of treatment.
The lens functions basically as a protective shield and prevents a damaged or ailing cornea from coming into contact with the eyelids and the air. Healing is thereby accelerated and pain is alleviated for as long as the lens is worn, which is on an extended basis (more than twenty-four hours). Read the rest of this entry »
Keratoconus is a relatively common hereditary disorder that manifests itself in adolescence. It affects both eyes, but one eye usually progresses faster than the other. During the course of this disease the cornea changes from its round shape to that of a cone, hence the name: kera meaning “cornea” and conus meaning “cone.” The apex of the cone is thin and may become scarred. In severe cases the apex may actually perforate.
The poor vision brought on by keratoconus is due to a highly exaggerated form of astigmatism that is poorly corrected by glasses. Until contact lenses became available, keratoconus patients often had to be satisfied with partially corrected vision and led less-than-normal lives. But contact lenses can provide almost perfect vision in most cases and are the best means of vision correction for this disorder.
Hard contact lenses are usually used because the smooth, dome-shaped shell plus the tears beneath it provide a new smooth, round refracting surface for the eye. Because the cornea is diseased, the eye may not tolerate conventional hard lenses. In that case gas-permeable contact lenses may be prescribed instead. Soft contact lenses, in general, do not work well with keratoconic eyes. As is the case with astigmatism, the pliable material from which they are made conforms to the misshapen cornea, duplicating the refractive error. Soft contact lenses may, however, correct a portion of the faulty vision. And in some cases the patient is fitted with hard lenses on top of the soft lenses, piggyback fashion, to take advantage of the comfort of the soft lens plus the sharp visual acuity provided by the hard lens. In all cases the lenses are difficult to manufacture, and the fitting process must be extremely exact to achieve acceptable results.
It is estimated that there are 8.5 million people in the United States who have some degree of color blindness. This is the common name given to the inability to distinguish colors and shades; some people have trouble with only a few colors, others see no colors at all. This inherited disorder affects mostly males: 8 percent of the male population is red-green color deficient, as compared with only one half of 1 percent of the female population. Read the rest of this entry »
Contact Lenses Care .
