Eye exams and contact lenses often go hand-in-hand. This often raises questions about the differences between a comprehensive eye exam and a contact lens exam.
A contact lens exam, which typically follows an eye exam, includes measuring parts of your eye and assessing your tear film to help find a suitable type and size of contact lens. Meanwhile, a routine eye exam is a comprehensive assessment of your prescription needs and overall eye health.
Regular eye exams are important because they can alert you to underlying health conditions. Similarly, a contact lens exam is important for finding comfortable contact lenses that match your needs.
What Happens in a Contact Lens Exam?
The purpose of a contact lens exam is to match you with a type of contact lens that fits your eyes, needs, and lifestyle. It may include the following components:
Assessing Visual Acuity
Your visual acuity refers to how well you see. We may investigate how well each eye sees on its own, how well they see together, and how well you see with or without corrective lenses. To do this, you may be asked to read letters of different sizes on a chart.
Measuring the Curvature of the Cornea
In this step, we’ll measure the shape and curvature of your cornea. The cornea is the outer, front layer of the eye. Corneal topography creates a map of your cornea that shows bumps, ridges, and other features across your cornea’s surface. This measurement is particularly useful if you’re interested in rigid gas-permeable (RGP) contact lenses.
Measuring Pupil or Iris Size
The pupil is the black hole in the middle of your eye. It helps adjust how much light enters your eye. Meanwhile, the iris is the coloured part of your eye, with common colours being brown, blue, green, and hazel. The iris contracts to dilate or shrink the pupil.
The pupil and iris can be measured using manual and automated methods. Manual methods include using a ruler or a reference card to measure pupil sizes. Automated methods include using a pupil gauge or other device for more accurate measurements.
Assessing the Tear Film
Dry eye and contact lens wear are connected. Because contact lenses can lead to dry eye, we may assess the quality of your tears to see if contact lenses are right for you, and if so, which type of contact lenses.
This is often done using Schirmer’s test, which involves holding paper to your eyelids and seeing how moist the paper will be after 5 minutes. Another method is using dyes to test how long your tear film stays on the surface of your eye after you blink.
Types of Contact Lenses
Different lifestyles and preferences may be more suited to certain types of lenses. Your options for contact lenses include:
- Hard contact lenses: These lenses are less likely to pick up debris, so it’s easier to keep them clean. However, they reduce oxygen flow to your cornea.
- Soft contact lenses: Many people find soft contact lenses more comfortable, but these lenses may increase the wearer’s risk of irritation and infection.
- Rigid gas-permeable (RGP) contact lenses: This type of contact lens combines features of hard and soft contact lenses.
- Extended-wear contact lenses: These lenses have been approved to be worn continuously for an extended period of time.
What Happens in a Comprehensive Eye Exam?
A comprehensive eye exam doesn’t only check whether your prescription is up-to-date. It’s also an opportunity to screen for eye and general health conditions that may not be immediately noticeable. Some diseases have very subtle symptoms, which is why routine eye exams are so important in early disease detection.
A comprehensive eye exam includes the following components:
Patient History
We may review your family medical history with you and discuss any vision concerns you may have. We may also ask about how you usually use your eyes, such as your work environment, or if you have hobbies that are visually demanding.
Assessing Vision
We will also measure our visual acuity (how well you see). This often involves reading letters on a chart.
At the same time, we may also assess your binocular vision—this is your ability to see with both eyes and perceive depth. Other possible assessments include prescription power, how well your eyes coordinate, and how your eyes move and focus.
Assessing Eye Health
As part of your eye exam, we’ll take a detailed look at the structures of your eye to help detect a range of conditions—from pink eye and blepharitis to more serious issues like glaucoma and macular degeneration.
At our clinic, we strongly recommend including an OCT (optical coherence tomography) scan as a regular part of your comprehensive eye exam. This advanced imaging technology allows the optometrist to assess your ocular health on a much deeper level.
One way to think about an OCT scan is like cutting into a cake—you can see the icing on the outside, but you won’t know if it’s chocolate or vanilla until you look inside. Similarly, an OCT lets your doctor see below the surface of your eye, revealing vital details about the retina, optic nerve, and macula that can’t be seen with standard testing.
Depending on what we uncover during your exam, additional tests like retinal photography or further scans may also be recommended.
Recommended Frequency of Eye Exams
The Canadian Association of Optometrists recommends the following eye exam frequencies:
- Infants should receive their first eye exam between 6 and 9 months of age
- Young children should get their eyes checked at least once between ages 2 and 5
- Youth aged 19 and under should get an eye exam every year
- Adults ages 20 to 64 should get an eye exam every 2 years
- Older adults aged 65 and up should get an eye exam every year
- Some underlying conditions may require more frequent eye exams; for example, adults with diabetes should get an eye exam every year
Ready for Your Next Eye Exam?
Is it time for your next eye exam? Or are you interested in trying contact lenses as an alternative to eyeglasses? Our team at Oxford Optometry offers adult and children’s eye exams along with contact lens exams and fittings. Our goal is to provide you with a comfortable eye care experience that meets your personalized needs. After all, everybody’s eyes are different!
To learn more about eye care or to discuss your vision concerns, book an appointment at Oxford Optometry today.
