Q. I am long-sighted, 45, and beginning to have pr^oblems 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.

Q. Is it true that contact lenses can prevent short sight from progressing?

A. No.

Q. Is it true that short sight can be cured by an operation on the cornea?

A. The procedures are dangerous and the effect often temporary. Permanent damage may occur. Not recommended.

Q. Shall I require to change my contact lenses as often as I change my glasses?

A. No. Much less often. You may save money in the long run.

Q. I sometimes see double with one eye when wearing my lenses. Is this serious?

A. This suggests that one lens is not centring properly. Not serious, but you should tell your fitter.

Q. My vision often fogs up but clears when I blink. What should I do?

A. Blink more. Contact lens wearers sometimes get into a bad habit of inadequate blinking. Make sure you don’t!

Q. Why is it important to put the plug in the sink when washing my lenses?

A. If you drop the lens you’ll never retrieve it!

Q. Do you recommend tinted lenses?

A. Yes, but not too deeply tinted. Tinted lenses relieve the light sensitivity that most wearers have, initially. They are also easier to find if dropped in water.

Q. Can I use a clean tissue to clean my lenses? A. No. Tissues always cause scratching.

Q. What should I use then?

A. Your finger tips — thoroughly washed first, of course.

Q. Is it easy to insert contact lenses in someone else’s eyes?

A. Very. Easier than putting them in your own — providing they will keep their eyes open properly.

Q. My mother has had cataracts removed. Could I learn to put in and remove her contact lenses for her?

A. Very easily. The specialist will be delighted to instruct you and your mother will bless you!

Q. What is the difference between an ophthalmic optician and an optometrist?

A. No difference.

Q. Who may fit and prescribe contact lenses?

A. An ophthalmic optician, an ophthalmic medical practitioner or an ophthalmologist.

Q. What is an ophthalmologist?

A. A doctor who is a specialist in the disorders of the eye.

Q. Whom should I see if I have major complications from contact lens wear?

A. An ophthalmologist. Your family doctor will refer you.

Q: Can contact lenses harm the eye?

A: Contact lenses are dangerous if you have a faulty lens, or do not maintain proper ocular hygiene, or don’t follow the recommended wearing and handling procedures. For instance, corneal abrasion can occur when the lens isn’t inserted properly. Corneal edema occurs if you overwear the lens. An eye infection may be caused by fingers or contact lens solutions that are contaminated. And foreign bodies can sneak under the lens and irritate the cornea.

With regard to the vast number of contact lens wearers, though, such complications have been remarkably rare.

Q: What is corneal edema?

A: It is the most common contact lens complication and the main reason you can’t wear lenses for twenty-four hours (except for extended-wear contacts). Edema means swelling, which is what happens to your cornea when you wear your lenses too long and deprive the cornea of oxygen. Even though gas-permeable lenses, soft lenses, and lenses that allow optimum tear exchange reduce the chance of edema, there is always less oxygen than normally reaches the naked eye. You’ll know when you’ve been wearing your contacts too long: your eyes will burn, turn red, be light sensitive; maybe you’ll see halos or rainbows around lights. Unless you’re too stubborn or highly motivated, the most appealing thought in the world will be that of removing your lenses, which is exactly the right thing to do. In minor cases your cornea will recuperate in a few hours (better yet—overnight). If you really overdo it, recovery may take several days and corneal abrasion may follow.

Q: What is conjunctivitis?

A: This is an infection of the conjunctiva, the mucous membrane that covers the white part of the eye and lines the underside of the eyelids. Conjunctivitis and other eye infections can afflict the contact lens wearer who doesn’t clean (and disinfect, in the case of soft lenses) his lenses according to instructions. It can also occur when wearers clean and wet the lenses with saliva, which is loaded with bacteria, viruses, and perhaps fungi. In addition to the ordinary garden-variety conjunctivitis (”pink eye“), there’s another form called “giant papillary conjunctivitis,” which is caused only by contact lens wear (the contact lenses themselves, deposits on the lenses, or any of the contact lens solutions). In treating the individual with this type of conjunctivitis I discard the contact lens and prescribe a steroid (cortisone) eye drop. Resolution of the disorder may take days or even weeks. Once the conjunctiva has healed, I order a new lens and then instruct the patient to use different solutions. For the hard contact lens wearer the correct solution is determined by trial and error. For the soft contact lens wearer I permit only the use of unpreserved saline and the heat method of disinfection. Happily, this type of conjunctivitis, when treated properly, rarely recurs. If it does reappear, cessation of contact lens use may be the only solution.

Q: What’s corneal abrasion?

A: Corneal abrasion is the term used when the surface layer of the cornea is scraped or scratched off. This can occur when you wear the contact lenses too long (overwear syndrome); with improperly fitted lenses; or by inserting, removing, or recentering the lens improperly. Sleeping with daily-wear lenses on often leads to corneal abrasion. The symptoms are decreased vision, burning pain, sensitivity to light, the sensation of having something in your eye, and copious tearing. Abrasion that follows corneal edema may not be evident until hours after the contact lenses have been removed. Healing is mercifully rapid: usually within thirty-six hours. You may take aspirin for the pain, and cold compresses may help. Consult your ophthalmologist to make sure there are no complications; he may also recommend that you wear a tight eye patch for the duration of the recuperative period to keep the eye immobile. Though most cases of corneal abrasion are minor, a severe infection can invade the damaged cells. While this is unlikely to occur, it is a possibility, so don’t treat corneal abrasions lightly.

Q: Can contact lenses cause drooping of the eyelids?

A: It’s rare, but the results of one study indicate that in a very few cases, contact lens wear can lead to a condition called blepharoptosis, resulting in eyelids that appear to droop. All the patients studied had been wearing hard lenses, some for many years. The researchers’ most likely explanation is that the condition was caused by excessive manipulation and rubbing of the eyelids, usually because of difficulties in inserting and removing the lenses. The trauma caused eyelid muscle damage. This condition can be corrected surgically.

Daily-Wear Contact Lenses. Conventional hard lenses, gas- permeable lenses, and soft lenses can be worn to correct vision following a cataract removal. But the problem of daily insertion, removal, and cleaning is a real one, and discourages many a potential daily wearer. Fear of inserting a foreign object into the eye; diminished dexterity; reluctance to handle tiny, delicate, almost invisible objects—all can add up to a less-thansuccessful scenario. The replacement rate with soft lenses is particularly high: the average life span of a pair is two years because of loss, torn lenses, or lens deposits. Because of their advanced age aphakes often have dry eyes, and soft lenses require a more lavish tear supply than do hard lenses. Also, loose lids, usually found as a product of aging eye, can cause fitting and wearing problems.

Many aphakes do, however, adjust to life with daily-wear contact lenses. Sometimes a willing friend or relative helps with the lens care and handling. Aphakes also have some distinct advantages to mitigate their particular problems when it comes to contact lens wear. Since the cornea has been cut (and nerves severed) during the cataract extraction, the eyes are less sensitive and contact lenses feel more comfortable. (Unfortunately this desensitization may mean that the aphake is less aware of any injury and damage to the eyes; therefore these patients require careful monitoring.) For those who can’t cope, there are two more alternatives: extended-wear contact lenses, and intraocular lenses.

Extended-Wear Contact Lenses. As discussed previously this is a recent development, and many eye practitioners feel that these lenses are the safest alternative. As such they have become the single most frequently prescribed form of contact lenses for aphakes. And with good reason: extended-wear contact lenses are comfortable and provide good visual acuity. Primarily they solve the biggest drawback of aphakic contact lens wear by eliminating the daily insertion, removal, and cleaning required of all other types of contact lenses. In fact, extended wear for aphakes was FDA approved before extended wear for so-called “cosmetic” use because of the very real and greater need for this type of lens.

Extended-wear contact lenses are initially inserted at the doctor’s office and worn continuously for up to one month or more. During periodic eye examinations at the doctor’s office the lenses are usually removed and cleaned and then reinserted. As with daily-wear lenses, sometimes a neighbor or a relative is enlisted to help remove, clean, and insert the lenses between office visits.

Extended wear does have its drawbacks. The lenses currently available will not fit everyone, but they are successful in an estimated 75 percent of the aphakic population. Since they wear them for longer periods of time, aphakes tend to have even more of a problem with protein deposits than normally occurs with the daily-wear lenses. The useful life of the lens is thus shorter, necessitating frequent replacement, though the “saline eyewash” has been shown to be an effective preventive that can be used without removing the lens. Wearers should be hygiene conscious and be willing to go to the doctor for the needed follow-up visits.

Intraocular Lenses. Although they are not contact lenses, plastic intraocular lenses are quite similar and offer a viable and permanent solution for the aphake. Each year a larger percentage of those who undergo cataract removal will have a lens implant, usually at the time of cataract surgery. As a result they have a new substitute lens built right into the eye; quite often vision is restored to 20 / 20 without glasses. This is the most convenient form of cataract correction, since the lens is never removed unless complications ensue.

The intraocular lens is the brainchild of the English ophthalmologist Harold Ridley, who developed the idea during World War II. He saw wounded RAF pilots with fragments of Plexiglas windshields embedded in their eyes. The plastic remained inert, which led him to the conclusion that intraocular lenses could be made from the same material (polymethylmethacrylate, or PMMA, the same plastic from which conventional hard contact lenses are made) and safely placed into the eye.

Since ophthalmologists do not know the long-term effects of intraocular lens implants, the best candidates for ocular implants are the elderly. If they have dry eyes and eyelid abnormalities, which preclude wearing contact lenses, the lens implant will be the best type of vision correction. On the other hand those who are very nearsighted, have detached retinas, poorly controlled glaucoma, diabetes, or other eye diseases, are advised to seek the other vision-corrective devices mentioned earlier.

About 10 percent of the intraocular implants result in complications. Many of these can be corrected without removing the implant. They may include dislocation of the implant, changes in the cornea, inflammation of the iris, retinal detachment, and increased pressure in the eye that could lead to glaucoma. At times the intraocular lens will have to be removed. Tests are still being conducted to study the longterm effects of intraocular lenses.

Future developments in this field lie mainly in the improvement of the lenses themselves. Another method of vision correction involves grafting “live” contact lenses onto the aphake’s cornea. Donor corneas are frozen and ground to size, then sutured onto the living host cornea. To date several such operations have been successful.

Canada, Australia, and Europe enjoyed several types of extended-wear contact lenses several years before we did. However, there is no Food and Drug Administration in those parts of the world, and because of this lack of strict monitoring control and quality, these lenses have posed a health problem, especially as related to corneal complications.

At first the only type of extended-wear lenses that the FDA approved were therapeutic bandage lenses worn on the cornea and the sclera for use in treating certain eye disease. However, the potential of these lenses for correcting refractive errors was soon realized, and eventually the FDA allowed a few contact lens manufacturers to produce extended- wear corneal lenses. A handful of qualified ophthalmologists and optometrists were then permitted to fit and investigate the extended-wear lenses as visual corrective devices.

They were approved for wear by aphakes since they have a pressing need for an alternative to the often unsatisfactory spectacles and available contact lenses. After five years of rigorous testing by a select group of ophthalmologists (of which I was one) and optometrists on a specially selected group of volunteer patients, the first two brands of extended-wear contact lenses were approved for general cosmetic use: Perma-Lens, fabricated from perfilcon A, a terpolymer, and made by Cooper Vision; and Hydrocurve II, composed of the polymer bufilcon A, and made by Continuous Curve, Inc., and Revlon.

The reaction of the eye to extended contact lens wear is even more important than in daily-wear contact lenses. The lenses must allow plenty of oxygen to reach the cornea because the cornea does not have the same opportunity to recover from prolonged oxygen deprivation as it does with daily-wear contact lenses. In addition, during sleep the eyelids are closed so the ocular physiology is different: there is no available oxygen from the atmosphere and there is an absence of oxygen- filled tears. The semirigid gas-permeable lenses would logically seem to fit the bill for optimum oxygen supply, but studies so far have revealed drawbacks in these lenses during prolonged wear. Except for the pure silicone lenses used by aphakes, the contact lenses that have been FDA approved to date for extended wear are all soft, and made of plastics similar to those from which conventional soft lenses are made, but modified to yield greater oxygen permeability. The rate of oxygen-carbon dioxide transmission through the lens material is determined by two major factors: the water content and the thickness of the lens. The higher the percentage of water contained in the lens material, and the thinner the lens, the more gas is exchanged. A very thin, very highwater-content lens, however, has so far proven to be too fragile to be practical. Thus, a lens manufacturer can take either of two roads to maximize gas transmissibility. It can design a relatively thick lens with a high water content (Perma Lens), or a very thin lens with a lower water content (Hydrocurve II).

Extended-wear lenses are therefore from 55 percent (Hydrocurve) to 75 percent (Perma-Lens) water. Conventional daily-wear soft lenses are on the average about 30 to 40 percent water. The Hydrocurve extended-wear contact lens is as thin as a single strand of hair (0.05 mm).

Oxygen transmissibility is not the only factor in lens wear, however, and thickness and water content not the only variables. The different materials have different properties, and there are different diameters, edge designs, and other design factors to be considered. For instance, the lower the water content of a lens, the higher the tensile strength it has, and the less it tends to accumulate deposits and support the growth of bacteria and fungus. This can mean a longer useful lens life, more comfort, and less frequent replacements. Lower water content yields a slightly more rigid lens, which generally provides better visual acuity. On the other hand the higher the water content, the softer will be the lens and the more comfortable it may feel. But the higher the water content, the more important it is to have adequate tear flow, since the tear flow is essential to keep the lens hydrated. Thinner lenses are more apt to fold and tear and are more difficult to handle. Also, it may be difficult to determine whether they have inverted or not.

Even with more than one brand to choose from, it is impossible to predict whether someone will be able to wear contact lenses for an extended period of time. The cornea and tear composition of each person are different, as is the tendency to form protein deposits and the ability of the eye to adapt to life with less oxygen and a diminished tear pump. It is up to the doctor to weigh the obvious benefits against the possible risks to the health of the eye. Now that extended wear has been FDA approved, any eye practitioner can dispense them, regardless of how much (or how little) experience he has had with them. This is the most promotable form of contact lens wear by far, and the media exposure can sometimes paint too pretty a picture, giving the consumer unrealistic expectations. It is especially important to have a highly experienced ophthalmologist monitor the health of your cornea during extended contact lens wear. True success comes only with strict supervision. Patients must understand the importance of compliance with a strict follow-up schedule of numerous eye examinations, during which subtle changes in the eye may be discovered, indicating that extended wear must be stopped.

Any sign of a problem (red eyes, reduced vision, discharge, or irritation) should be reported to the doctor at once and the lenses should be removed immediately. Reinsertion of the lenses should occur only after your doctor has made certain that your eyes have returned to their normal, healthy state.