Disposable Contact Lenses

Disposable soft contacts are the most popular contact lenses prescribed and sold in the United States. These lenses are designed to be worn for a limited number of days and then discarded.

Replacing contact lenses frequently reduces the build-up of protein and other organic and inorganic materials (substances contained in the eyes’ tear film) on contact lenses over time that can cause eye discomfort and contact lens-related eye infections.

Types of Disposable Contact Lenses

The most convenient disposable contact lenses are daily disposables. These lenses are designed to be worn only once, then removed and discarded at the end of the day.

Though daily disposable contacts might sound expensive, the annual cost of wearing these lenses is only slightly higher than wearing other types of contact lenses. Also, there is little or no need to purchase contact lens solutions for daily lens care when you wear daily disposable lenses.

Other types of disposable soft contact lenses include lenses that are designed and recommended for the following replacement schedules:

  • Weekly
  • Every two weeks
  • Monthly
  • Quarterly

 

Lenses designed for monthly or quarterly replacement sometimes are called “frequent replacement” or “planned replacement” contact lenses, rather than “disposable” lenses.

Lens Materials

Disposable soft contact lenses are available in two types of materials: standard hydrogels and silicone hydrogel materials. Contact lenses made of either of these materials are thin, soft and pliable. The word “hydrogel” means the material attracts and holds water (“hydro”), which gives the material its soft, pliable (“gel”) characteristics.

Silicone hydrogels are newer soft lens materials that transmit more oxygen to the surface of the eye than standard hydrogels. This greater “breathability” of silicone hydrogels has quickly made them the most popular materials for both disposable and extended wear contact lenses.

Wearing Schedule

The wearing schedule of disposable contact lenses refers to how long the lenses should be worn before they are removed. (This is different than the “replacement schedule” of the lenses, which refers to when the lenses should be discarded and replaced with new lenses.)

There are two basic types of wearing schedules for disposable contact lenses:

  • Daily wear means the lenses should be worn only during the day and removed before sleep (including naps).
  • Extended wear means the lenses are approved for continuous day-and-night wear, without needing to be removed before sleep.

 

Most extended wear disposable contacts are FDA-approved for up to 7 days of continuous day-and-night wear. Some lenses are approved for up to 30 days of extended wear. (These 30-day lenses are sometimes called “continuous wear” contacts to distinguish them from 7-day extended wear lenses.)

However, just because extended wear lenses are approved for specified maximum periods of continuous wear, this does not mean everyone can successfully wear the lenses day and night.

Many contact lens wearers — due to dry eyes or other reasons — cannot tolerate any amount of overnight wear of contact lenses. Others, even if their eyes can tolerate overnight wear, should not sleep while wearing extended wear lenses due to the significantly higher risk of eye infection when contact lenses are worn during sleep.

Are Disposable Contacts Right for Me?

Disposable contact lenses usually are a good choice for anyone who has nearsightedness, farsightedness and/or astigmatism and can safely and comfortably wear contact lenses.

Though daily disposable contact lenses are available in designs that correct astigmatism (as well as nearsightedness or farsightedness), disposable contacts designed for weekly, two-week or monthly replacement tend to have a wider variety of lens parameters for astigmatism correction.

There even are multifocal disposable contact lenses for adults over age 40 who are experiencing presbyopia — the normal age-related loss of the eyes’ ability to focus on near objects and read small print. Multifocal disposable contacts reduce or eliminate the need to wear reading glasses over contact lenses when presbyopia becomes apparent.

Disposable contact lenses — especially daily disposable lenses — also are a great choice if you want to wear contacts but suffer from allergies. Because you discard them after each use, there is less time for allergy-causing substances (allergens) to accumulate on the surface of the daily disposable contacts.

For this reason, many eye care professionals recommend daily disposable contacts as problem-solving lenses for contact lens wearers who are experiencing allergy-related eye irritation with their current contacts.

How Much Do Disposable Contacts Cost?

Disposable contact lenses are very affordable and cost less than you might think.

Modern lens fabrication processes have greatly reduced the manufacturing costs of disposable contact lenses so more people can enjoy these lenses without breaking their budget.

Even daily disposable lenses — which tend to be more expensive on an annual basis than disposable lenses designed for less frequent replacement — can cost only a little more than a dollar per day, depending on your prescription.

To get an exact quote of the cost of disposable contact lenses that are best suited for your needs, visit your eye care professional for a comprehensive eye exam and contact lens consultation.

Article ©2014, Access Media Group LLC. Source: Disposable Contact Lenses: A Healthy Choice by AllAboutVision.com.

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Progressive Lenses

Progressive lens “Zones”

Progressive lenses, sometimes referred to as “no-line” bifocals, provide vision correction for the three basic vision zones – distance vision, intermediate vision, and near vision. Because they provide vision in these three zones, they are often thought of as a type of trifocal.

In reality, progressive lenses are neither a type of bifocal or trifocal – they are “aspheric” in design, which means the curvature (and focusing power) gradually changes from the top of the lens to the bottom. It is this gradual change or “progression” in power from top to bottom that gives rise to the name “progressive.”

Progressive lenses provide a great solution for many people who find their present lens design limits their vision for a particular distance or activity. Progressives offer a range of vision as close to natural as can be obtained from prescription eyeglasses. They provide clearer vision not just for distance, intermediate and near but also for all distances in between. Because there is no abrupt change of power in the lens, there are no visible dividing lines.

The distance zone of the lens allows you to see objects from a few feet away to as far as your eye can see. The mid-range portion of the lens (“progression corridor”) allows you to clearly see anything at an arm’s length, such as your computer screen, objects on your desk, or items on a shelf at the supermarket. The lowest part of the lens, the near zone, allows you to see up close. The design of progressive lenses also allows a more natural and relaxed head posture when viewing objects at slightly longer reading distances, such as a newspaper or computer screen.

More Options – A variety of progressive lens designs are available today. Some progressives are designed with a wider intermediate zone to work especially well for computer use. Others have a larger reading zone. In the past, a larger frame was often required when selecting progressive lenses. If a frame was too small, a large portion of the near zone was removed when cutting the lens to fit the frame. Many lens manufacturers now offer “compact” progressive designs that work very well with smaller frames. Progressives are available in glass, plastic, polycarbonate, and photochromic (light-sensitive) lenses.

Modern progressive lenses offer outstanding clarity and comfort for seeing at all distances. Modern designs also make the adaptation process much easier than in the past. if you’ve tried progressives before, realize that much has changed in both lens design and materials. The next time you update your glasses, be sure to ask if progressive lenses might be right for you.

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