Over 24 million people choose contact lenses to correct their vision. When used with care and proper supervision, contacts are a safe and effective alternative to eyeglasses. With today’s new lens technology, many people who wear eyeglasses can also successfully wear contact lenses.
Successful contact lens wear requires an extensive exam by an ophthalmologist or optometrist to determine if you are a good candidate. An initial fitting with lenses will be followed by training in our office on how to apply and care for the lenses and then annual checkups are scheduled to monitor your eye health and success. Annual exams are required, according to State law, for all annual prescription refills.
Contacts are thin, clear disks that float on the tear film that coats the cornea, the curved front surface of the eye. Contacts correct the same refractive conditions eyeglasses correct: myopia (nearsightedness), hyperopia (farsightedness) and astigmatism (an oval-rather than round-shaped cornea).
Contact lenses can be made from a number of different plastics. The main distinction among them is whether they are hard or soft lenses. Most contact lens wearers in the United States wear soft lenses. These may be daily wear soft lenses, continuous wear lenses or disposable lenses. Toric soft lenses provide a soft lens alternative for people with slight to moderate astigmatism.
Hard lenses are usually not as comfortable as soft lenses and are not as widely used. However, rigid gas permeable lenses provide sharper vision for people with higher refractive errors or larger degrees of astigmatism.
Most people can tolerate contact lenses, but there are some exceptions. Conditions that might prevent an individual from successfully wearing contact lenses include dry eye, severe allergies, frequent eye infections, or a dusty and dirty work environment.
Individuals who wear any type of contact lens overnight have a greater chance of developing infections in the cornea. These infections are often due to poor cleaning and lens care. Another factor is that contact lenses prevent adequate oxygen levels from reaching the cornea through the closed eyelid at night. It is for this reason that most practitioners discourage overnight wear of contact lenses, even so-called “continuous wear” types.
Soft contact lens insertion and removal instructions.
Hard Contact lens insertion and removal instructions.
Types of Soft Lenses
Conventional lenses are used much less frequently today in the advent of planned replacement and disposable lenses, but they are still useful for patients with a very high or unusual prescription. Furthermore, conventional lenses require much more maintenance.
- Conventional lenses (last up to 1 to 1½ year per lens – less common).
- Continuous wear or planned replacement lenses (last between one and six months per lens, varies among brands).
- Disposable lenses (last between one and two weeks per lens).
- Daily disposable lenses (last one day per lens – less popular).
- Soft Continuous Wear Contact Lenses are Most Suitable for:
- Disposable or Frequent Replacement Lenses are Most Suitable for:
- Rigid Gas Permeable Contact Lenses are Most Suitable for:
Soft Continuous Wear Contact Lenses are Most Suitable for:
- Patients who are highly motivated to follow the lens-care and follow-up visit schedule.
- Patients who understand the increased risk of corneal ulcers and other complications.
- Patients who are in good general health and good ocular health. They are not recommended for diabetic patients.
Disposable or Frequent Replacement Lenses are Most Suitable for:
- Patients who have marginally dry eyes.
- Patients who have eyelid inflammatory conditions such as blepharitis.
- Patients who have significant allergies.
- Patients who use systemic medications, such as antihistamines or calcium supplements.
- Patients who work in a dusty or dirty involvement.
- Patients who are active in outdoor activities or sports
- Patients who spend a lot of time using a computer or reading.
Rigid Gas Permeable Contact Lenses are Most Suitable for:
- Patients who cannot achieve acceptable vision with soft lenses (some patients with keratoconus, astigmatism or corneal transplant.
- Patients who have had problems with soft contact lens deposits.
- Patients who have difficulty handling soft contact lenses.
- Patients who have moderately dry eyes or poor quality tear film.
Contact lens wearers should be aware of possible complications involved in using contact lenses.
Contact Lens Information
Contact lenses are a reasonable alternative to glasses to attain good vision. However, contact lenses are not without risk.
The most common complications occur due to poor hygiene or compliance. We recommend having a set of glasses in case you must discontinue use of your contact lenses due to problems. Annual exams by your eye doctor are highly recommended to avoid serious complications and ensure your ongoing eye health.
The following conditions are possible complications of contact lenses. You, the patient, must be aware of the potential hazards and accept these relative risks in addition to the benefits of contact lenses.
Contact Lens Over-wear
This occurs when a contact lens is worn longer than the cornea can tolerate. Not enough oxygen gets to the cornea resulting in temporary discomfort and blurred vision. The treatment is to discontinue wearing the contact lenses for a few days.
This is a “scratch” on the surface of the cornea resulting from a poorly fitting contact lens or possibly from foreign material under a contact lens. Over-wear can also cause an abrasion. Infection may result from this condition. Treatment includes antibiotics and a bandage contact lens. Infection may result from this condition.
In this condition, the eye becomes red and irritated in response to the cleaning and/or storage solutions or seasonal allergies. It is more often seen with soft contact lenses and usually is a reaction to the preservatives in these solutions. Treatment includes changing to different solutions and storage methods.
Tight Lens Syndrome
This is more often seen with soft and extended wear lenses. The lens, which had previously fit well, “tightens up” and does not allow tears and oxygen to reach the cornea. This can lead to a corneal abrasion. Treatment is to refit the lens.
This is usually due to contact lens over-wear, poor fitting lenses or inadequate follow-up. Occurs most frequently with hard and gas permeable lenses, but can occur less frequently with soft lenses. In this condition, the shape of the cornea becomes altered in response to the contact lenses. If severe warpage occurs, the lenses may no longer fit well and discomfort results. Treatment includes discontinuation of lens wear until the warpage resolves, which may take weeks to months. During this healing time, vision may fluctuate, requiring a change in the glasses prescription one or more times. Occasionally, the warpage may not resolve and the astigmatism created may persist.
Giant Papillary Conjunctivitis (GPC)
In this condition, there is redness and discomfort when wearing the contact lenses. It is more often seen with soft contact lenses and most likely results from over-wear or an allergic reaction to deposits which have formed on the lenses, or to the lens material itself. Treatment includes temporary discontinuation of lens wear or switching to a new or different design lens. GPC may occasionally result in inability to continue lens wear at all.
This is the most severe complication of contact lenses. It is more often seen with continuous wear of soft contact lenses. In this condition, trauma to the cornea from the contact lens results in a bacterial infection. This may require hospitalization for the frequent antibiotic eye-drops required to control this infection. Corneal scarring may result in spite of effective treatment, and may result in loss of vision. Corneal transplantation may be required in some cases for restoration of vision.