What to Expect During a Contact Lens Exam?

If you need prescription lenses to help you to see clearly and you are considering wearing contact lenses for the very first time, you may well be wondering what to expect. Many people are unaware that the examinations and assessments needed for contact lenses are a little different to those used for patients who only wear glasses. This is primarily for two reasons. Firstly, contact lenses sit directly on the surface of the eyes rather than a short distance in front of them, and this means that the prescription needed is very different in contact lenses to glasses. Secondly, your eye doctor will need to make sure that you get the right size and variety of contact lenses, and this means that additional tests and scans will be needed. 

To help you understand what will happen, here’s what you need to know about what to expect during a contact lens exam.
 

A comprehensive eye exam

Before you can get started with the contact lens part of the appointment, you will first undergo a comprehensive eye exam. The purpose of the assessments that are performed as a part of this is to check the health and condition of your eyes. This is very important, since there are some eye diseases and conditions that make it impossible to wear contact lenses, and your eye doctor will need to be satisfied that your eyes can support contact lens use. 
 

Getting the correct fit for your contact lenses

There is no ‘one-size-fits-all’ solution when it comes to contact lenses and your eye doctor will need to take very precise measurements to establish which variety and size will be best for you. This will include:
 

• Measurement of the curve of your cornea. This is usually carried out using a tool called a keratometer, or a corneal topography scan which produces a 3D image of the cornea and surface of the eye. If the surface of your eyes is irregular, a condition known as astigmatism, you may need to have a specific type of contact lens called a ‘toric’ lens, which is very successful at correcting this common issue.   

• Measurement of the size of your iris and pupil. The iris is the colored part of your eye, while the pupil is the small, dark dot in the center. Their size is important when it comes to choosing the size of your contact lenses, particularly if you have a condition that means that you need specialty contact lenses. This measurement can be carried out using a hand-held rule or an instrument called a slit lamp. 

Tear film evaluation

Another important yet very simple part of a contact lens is a test known as tear film evaluation. This looks at how much natural tear film your eyes produce, to ensure that there is a sufficient amount to keep the lenses and your cornea moist and comfortable. The test usually involves a tiny strip of paper being placed onto your lower eyelid to see how well your tears moisten it. If you are found to have insufficient tear film you may still be able to wear contact lenses, but you may need a specialty type. 
 

Contact lens fitting

Once your eye doctor has decided which lenses will be best for you, a generic prescription of that lens type will be given to you for you to try. This will allow them to assess how well it fits, as well as check that you can handle the lenses and put them in and take them out without assistance. When they are happy with the selection, they will order your prescription lenses for you. Once they arrive, you will return to collect your lenses and obtain the advice you need about using and caring for them.

If you have any other questions about what to expect during a contact lens exam or if you are considering contact lenses, please get in touch with our knowledgeable team. We can be reached at (804) 353-3937.