Eye Exam & Contact Lens Fitting

Eye Exam & Contact Lens Fitting

For years, more and more people have been switching to contact lenses. Contact lens technology has evolved rapidly and with today's variety of contact lenses, there are lenses for just about everyone. Switching from eyeglasses to contact lenses begins with an eye exam for contact lenses. After the contact lens exam comes a separate contact lens fitting session.

• What are Contact Lens Measurements
• Trial Pair of Contact Lenses
• Why does it cost more for a contact lens exam?
• Advantages and Disadvantages of Contact Lenses
• Can I Choose my own Contact Lenses?
• Difference Between Eyeglasses and Contact Lenses

A comprehensive eye exam comes first

Before being fit with contact lenses, a comprehensive eye exam for contact lenses is performed. In this exam, your eye doctor determines your prescription for corrective lenses (just a glasses prescription at this point) and checks for any eye health problems or other issues that may interfere with successful contact lens wear.

If all looks good during your eye exam, the next step is a contact lens consultation and fitting.

What to expect during a contact lens fitting

With so many contact lens choices, the first part of the consultation is a discussion with your eye doctor about your lifestyle and preferences regarding contact lenses. One choice that today's contact lenses allow you to make is whether you want to change your eye color. Different eye colors are available with contact lenses. Other options include whether you want contact lenses that are designed to be replaced daily or those which can be worn for more extended periods. Most people choose soft contact lenses for their ease and comfort. However, there are also advantages of hard or what is called rigid gas permeable (GP) lenses. All the specifics will be discussed prior to your contact lens fitting.

Believe it or not, if you need bifocals, you can even opt for multifocal contact lenses or monovision (a prescribing technique where one contact lens corrects your distance vision and the other lens corrects your near vision). Once you have determined the type of contacts you want, the next step is the actual contact lens fitting.

If You Are New Contacts Wearer

If this is the first time you are trying contact lens, you need to have a complete eye exam in and evaluation to make certain you are a good candidate for wearing contacts. Your doctor will ask about your vision goals. For example, you may only want to wear contacts for sports once per week, or you want your contacts to replace your glasses for everyday activities.

There are many choices in contact lenses these days, so your eye doctor will listen carefully and choose the lens that will best meet all your needs.

Additional Tests and Procedures

Your eye doctor will administer various tests designed to evaluate your eyes for contact lens wear. One important test is corneal topography, a test that maps out the different aspects of your cornea. Corneal topography displays results in a way that is very similar to the topography of mountains. The test results in a map of colors - reddish colors display steeper areas of the cornea, and bluish colors describe flatter areas. Contact lenses rest on your cornea, so it’s important that corneal curvature is measured precisely to ensure an optimal and healthy fit.

Another important test is the slit lamp examination. The slit lamp exam is generally performed during a regular eye examination, however, your eye doctor will spend more time doing a slit lamp examination for a patient who wears contact lenses. Sometimes eye health problems are diagnosed during this test, and they need to be treated before the contact lens fitting can proceed.

Fitting the Contacts

Your eye doctor will discuss different contact lens options with you, and once you decide on which ones will be best, you will try on diagnostic contact lenses. Your eye doctor will administer another slit lamp examination to determine if the lenses fit properly. Finally, a visual acuity test will be performed to determine how well a contact lens corrects your vision.

Once the contact lens fitting is complete, if you've never worn contact lenses, your doctor will teach you how to insert, remove and disinfect the lenses. Hygiene, cleanliness, and disinfection are essential for successful contact lens wear. Your doctor will probably ask you to wear the contact lenses for a week before returning for a follow-up visit. At your follow-up visit, your doctor will recheck the fit of the contact lenses, and ask about your vision and any problems you may be experiencing. At this point, your eye doctor will try fitting you with a new lens, or finalize your prescription. If you are dissatisfied with your vision or the comfort of the lenses, your eye doctor will schedule additional follow-up visits. Certain lenses, such as toric lenses for correcting astigmatism or multimodal lenses for correcting presbyopia, can take additional time to achieve a comfortable fit.

What are Contact Lens Measurements

Just as one shoe size doesn't fit all feet, one contact lens size doesn't fit all eyes. If the curvature of a contact lens is too flat or too steep for your eye's shape, you may experience discomfort or even damage to your eye. Measurements that will be taken to determine the best contact lens size and design for your eyes include:

• Corneal curvature: An instrument called a keratometer is used to measure the curvature of your eye's clear front surface (cornea). This measurement helps your doctor select the best curve and diameter for your contact lenses.
• If your eye's surface is found to be somewhat irregular because of astigmatism, you may require a special lens design of lens known as a "toric" contact lens. At one time, only gas permeable contact lenses could correct for astigmatism. But there are now many brands of soft toric lenses, which are available in disposable, multifocal, extended wear and colored versions.
• In some cases, a detailed mapping of the surface of your cornea (called corneal topography) may be done. Corneal topography provides extremely precise details about surface characteristics of the cornea and creates a surface "map" of your eye, with different contours represented by varying colors.
• Pupil and iris size: The size of your pupil and iris (the colored part of your eye) can play an important role in determining the best contact lens design, especially if you are interested in GP contact lenses. These measurements may be taken with a lighted instrument called a biomicroscope (also called a slit lamp) or simply with a hand-held ruler or template card.

• Tear film evaluation: To be successful wearing contact lenses, you must have an adequate tear film to keep the lenses and your cornea sufficiently moist and hydrated. This test may be performed with a liquid dye placed on your eye so your tears can be seen with a slit lamp, or with a small paper strip placed under your lower lid to see how well your tears moisten the paper. If you have dry eyes, contact lenses may not be right for you. Also, the number of tears you produce may determine which contact lens material will work best for you.

Trial Pair of Contact Lenses

A Contact Lens Fitting Usually Results in Trial Lenses

No matter how comprehensive the eye exam for contact lenses, most eye doctors will give you a set of trial lenses just to confirm that they are the right choice for your eyes. With lenses in place, your doctor will use the slit lamp to evaluate the position and movement of the lenses as you blink and look in different directions. You will also be asked how the lenses feel.

Most people wear trial lenses for at least 15 minutes so that any initial excess tearing of the eye stops, and your tear film stabilizes. Then, you will learn about how to care for your lenses and how long to wear them. You will also receive training on how to put in and take out your new lenses. While it may seem difficult at first, most people quickly learn how to use contacts lenses.

Your contact lens prescription

After finding a contact lens that fits properly, is comfortable for you and provides good vision, your doctor will then be able to write a contact lens prescription for you. This prescription will designate the contact lens power, the curvature of the lens (called the base curve), the lens diameter, and the lens name and manufacturer. In the case of GP contact lenses, additional specifications may also be included.

Follow-up visits confirm the fit and safety

Your contact lens fitting will involve a number of follow-up visits so your doctor can confirm the lenses are fitting your eyes properly and that your eyes are able to tolerate contact lens wear. A dye (like the one used to evaluate your tear film) may be used to see if the lenses are causing damage to your cornea or making your eyes become too dry.

Often, your doctor will be able to see warning signs before you are aware a problem with your contact lens wear is developing. If such warning signs are evident in your follow-up visits, a number of things may be recommended, including trying a different lens or lens material, using a different lens care method, or adjusting your contact lens wearing time. In occasional cases, it may be necessary to discontinue contact lens wear altogether.

Routine contact lens exams

Regardless of how often or how long you wear your contact lenses, your eyes should be examined at least once a year to make sure your eyes are continuing to tolerate contact lens wear and show no signs of ill effects from the lenses.

Why does it cost more for a contact lens exam?

Patients often wonder why a contact lens examination costs more than a regular eye exam. The reason is that fitting patients with contacts lenses involve additional tests and time (see the section on contact lens fittings).

Expertise is required when fitting contact lenses, as this skill is both a science and an art. The process takes time, usually several visits, special tests and a doctor’s expertise. These factors are in addition to the tests that are part of a regular comprehensive eye health and vision examination. Each patient has individual eye anatomy, eye health,  prescription type and needs, which makes contact lens evaluations and fittings unique for each patient.

Advantages & Disadvantages of Contact Lenses

To wear or not to wear contact lenses has been hotly debated for a long time. There are many doctors and patients who believe strongly in the benefits of contact lenses, and there are many who would believe the disadvantages and risks definitely outweigh the positives. The benefits and risks can be debated, but the fact is that more than a hundred and fifty million people wear contact lenses in the world today. While that number is much smaller compared to the number of people wearing glasses, but it is a substantial figure. What’s better for you, wearing contact lenses or glasses?

Advantages of contact lenses

• Contact Lenses (contacts) provide excellent vision correction.
• Contacts eliminate the need to wear eyeglasses all the time.
• Contacts provide better side vision than eyeglasses.
• A wide range of lens types is available to meet individual needs.
• Contacts cost more than eyeglasses but less than surgery
• Many people prefer the way they look when wearing contacts over eyeglasses.

Disadvantages of contact lenses

• Cleaning and disinfecting your lenses can be complicated and inconvenient. You need good hand-eye coordination to clean, insert, and remove the lenses.
• There is an increased risk of corneal infections, scratches, and scrapes.
• Lenses can be easily damaged or lost.
• Some people can't wear contact lenses comfortably. After going through the initial discomfort and expense of contact lenses, some people continue to find them uncomfortable or otherwise unsatisfactory.
• Wearing contact lenses can cost at least $150 per year, including the costs of cleaning and disinfecting solutions. People who have to replace their lenses or change prescriptions regularly may spend much more. The cost of the lenses varies according to the type of lens you wear.
• In some work areas, you will need to use protective eyewear if you wear contact lenses.

 

Pragmatic Assessment Of Contact Lenses Pros And Cons

People suffering from Myopia or nearsightedness, or astigmatism, are often happier with contact lenses. Farsightedness or hypermetropia is a condition that is often better treated with eyeglasses. The different problems in your vision should be considered while debating the pros and cons of contact lenses.

Aesthetics plays a big part in the contact lens versus eyeglasses decision. However, not everyone agrees on who looks better with glasses, or contact lenses. Some people like the idea of changing their eye color with contacts. Other people don’t like how eyeglasses feel on their face.

Sometimes contact lenses can cause allergies and they can become unusable should a person have a severe eye infection. This is not the case with eyeglasses. It is easier to keep the eyeglasses clean and disinfected. Whenever you are putting something into your eye you are taking more of a health risk than not doing so. However, glasses can fog up preventing vision and can become dirty, which could also lead to eye infections.

There are some serious contact lenses pros and cons. Make sure to completely discuss all the issues with your eye doctor before making a decision. Don’t just choose contact lenses because everyone else is. Weigh the aesthetic advantages against the costs and the hassle that you would have to deal with daily.

Can I Choose My Own Contact Lenses?

With today's technology, there are many brands of contact lenses available. Different contact lenses have both common and unique features, which are suitable for different users. Therefore, there is not a single brand that is best for everyone, and you must find the best contact lenses that are suitable to your own needs. When you shop for clothing, it is more important to choose clothes because they fit, rather than because they are a certain brand. The same goes for contact lenses. There are many different brands of contact lenses to choose from, and it’s important that you choose the brand that is right for your personality. Choose a lens which provides a good fit, provides good vision and is comfortable to the eye. There is a lot of advanced technology in contact lenses. Some brands offer more breathability and wettability, some offer distance and reading combinations within one contact lens. Now patients with various eye conditions, including astigmatism and dry eyes, can wear contact lenses designed especially for them.

There are so many different types of contact lenses available today, that without some expertise, it is almost impossible to know which ones are right for your particular eyes and lifestyle. Soft contact lenses come in monthlies, extended wear, and dailies. You can choose soft contact lenses that are transparent, visibility tint (slightly tinted to be easier to see), enhancement tint (enhances your eye color), or color tint (changes your eye color). If you have astigmatism, there are toric lenses available, and also GP contact lenses. There are other lenses available for patients with other eye conditions. How can you know what is best for you?

Our eye doctor will evaluate your eyes and your living environment to recommend the best possible contact lenses for you. You can also ask your eye doctor about the latest developments in the contact lens industry. Make sure your doctor is offering the latest technology to you. Your eye doctor is an expert in eyes and knowing which contact lenses will be best for you. It’s best to follow your eye doctor’s recommendation. The contact lens fitting involves follow-ups, to be sure that the contact lenses are right for you, and if they are not, your eye doctor is the best person to evaluate what is not working well, and which contact lenses might be a better choice.

Can everyone wear contact lenses?

While the vast majority of people can wear contact lenses, they are not suitable for everyone. There are many reasons why some people are unable to wear contact lenses. Certain eye health conditions make it problematic to wear contacts, such as dry eye syndrome. Sometimes the shape of the eye is incompatible with wearing contact lenses. Other issues include a very high nearsighted prescription that can not be corrected with contact lenses or an allergy to the disinfecting solution or contact lens. Some experts even suggest diabetics should stay away from wearing contact lenses because they are prone to infections and their bodies may not tolerate even a mild infection.

The truth is that these are the exceptions to the rule, that the vast majority of people can wear contact lenses. Even people who suffer from different eye conditions, including dry eye, who consult with an eye doctor who specializes in special contact lenses, will often find contacts that they can wear, and are comfortable. If you are not sure if you are a candidate for contact lenses, speak with an eye doctor who specializes in fitting special contact lenses.

Difference Between Eyeglasses & Contact Lenses

Eyeglasses	Contact Lenses
The distance between your eye and the lens sometimes creates distortion.	Worn right on the eye, for more natural vision.
Poor peripheral (side) vision.	Your entire field of view is in focus. This is especially important in sports and in driving, where you need to see as much around you as possible.
Constant awareness of frame and lens edge, as well as reflections off the backside of the lens.	With contacts, no annoying obstructions or reflections are in view.
Uncomfortable weight on your face and ears. Periodic need for tightening or other adjustment.	No weight and resulting discomfort. No frame constantly slipping down your nose.
Glasses fog up with changes in temperature.	Contacts don't fog up.
Virtually no chance of getting an eye infection	If used improperly can damage your eyes
No worrying about packing supplies for a trip	Need to bring supplies with you whenever you go away
Glasses are a distraction during games and sports.	No distractions, which makes contact lenses a favorite among athletes.
Fashionable and inexpensive non-prescription sunglasses are not an option if you wear eyeglasses.	A whole wardrobe of fashionable, functional, affordable sunglasses is available to contact lens wearers.
Make a fashion statement, and you can choose which ones you want to wear each day	Irrelevant for fashion
Eyeglasses can be problematic to wear in rain or snow.	Contact lenses won't collect precipitation and blur your vision.
Glasses are an unnatural, distracting barrier between your eyes and the world.	Contacts don't detract from your natural appearance; they let people see your eyes.

There are many differences between glasses and contact lenses, but there are also similarities. Both correct your vision, require care in handling and diligence in cleaning, and both are affordable.

Best contact lenses for astigmatism

There are three types of contact lenses that are suitable for people with astigmatism. Soft toric contact lenses, hybrid contact lenses, and gas permeable (hard) contact lenses. To know which one is best for you, speak with an eye doctor who specializes in contact lens fittings. There are different considerations for each type of lens. You will need to speak to  your eye doctor about what will work for your lifestyle, and your eye doctor will need to examine your eyes to determine which type of lens will best correct your vision. Of course comfort is as important as vision correction. Your doctor may try several lenses to see which one works best for your particular eyes.

Best contact lenses for dry eye

Dry eyes present a particular problem for contact wearers. However, there are excellent contact lenses for dry eye sufferers. Most people with dry eye prefer to wear soft contact lenses because they are often more comfortable.  Soft contact lenses are made of a flexible plastic that allows oxygen to pass through to the eye. Soft lenses are called hydrogel, which is a gel made mostly of water. There are types that can be worn for a day and then thrown out (disposable), or kept in for up to 30 days (extended wear).

Extended-wear contacts can cause more problems with dry eyes. Doctors recommend switching to disposable lenses. Changing your contact lenses often prevents protein deposits from forming on the lenses, which can make your eyes feel even. Lenses that are made from silicone hydrogel cause less water to evaporate and may reduce dry eye compared to regular hydrogel contacts. Proclear is the one brand of disposable lenses that is FDA-approved for people with dry eye syndrome. It contains phosphorylcholine (PC), which is supposed to attract water and keep your eyes feeling moist.

Another point to consider is lens water content. Soft contact lenses are categorized by how much water they contain. Low water content lenses contain less than 40% water, while high water content lenses contain more than 60% water. Lenses with high water content can actually cause drier eye than those with lower water content. They send more moisture to the eye when you first put them in but can dry out faster. Your eye doctor may recommend that you try lenses with different water contents until you find one that works for you.

Another consideration is lens size. Most contact lenses measure about 9 millimeters (mm) in diameter. They cover just the colored part of the eye (the iris).

Scleral contact lenses measure 15 to 22 mm. They cover the white part of the eye (the sclera). Scleral lenses are also gas-permeable, meaning they let oxygen reach the eye’s surface. They can help keep more moisture in the eye than smaller contact lenses.

The bottom line for choosing contacts that will be good for your eyes when you suffer from dry eyes is to consult an eye doctor who specializes in fitting contact lenses. Your eye doctor has experience knowing which contact lenses work best for people with dry eyes and will be able to guide you better than anyone else, based on your own particular needs and eye health.

Routine Contact Lens Exams at Lesslie Vision Care

Regardless of how often or how long you wear your contact lenses, your eyes should be examined at least once a year at by your eye doctor to make sure your eyes are continuing to tolerate contact lens wear and show no signs of ill effects from the lenses.