The eye exam for eyeglasses is different from contact lenses because it includes special tests that are not included in the typical eye exam. Scheduling an appointment for an eye exam ensures you get an updated contact lens prescription and proper contact lens fitting. Getting a general eye exam and contact lens exam is more convenient if you get it from the same eye care professional. There is a possibility that certain tests may be repeated if you have these exams performed by different ECPs for accuracy and safety for contact lens fitting. If the ECP performing contact lens exam does not have a record of the general eye exam, duplicate testing must be done.
The Process of Contact Lens Fitting
Visual acuity is tested during an eye exam by using an eye chart and other tests to determine eye health. Additional information will be asked by your eye doctor to determine preferences about contact lenses. Color contact lenses, disposable or overnight wear, rigid gas permeable (RGP or GP), soft lenses are options to be discussed by eye doctors. Some individuals have vision problems that require special lens fitting. An example would be presbyopia, multifocal, or bifocal contact lenses will be recommended to correct this. There is another option which is monovision that corrects one eye for distance vision and another eye for near vision.
Measurements of Contact Lens
The sizing of contact lenses differs from one another. Discomfort will be present if the curvature of the contact lens does not match the eye’s shape.
Cornea measurement is measured using a keratometer which helps to determine the appropriate curve and size for your contact lens. Corneal topography is an instrument used to perform additional measurements of the cornea which provides the exact details about the surface characteristics.
Pupil measurement is measured using a ruler that shows different pupil sizes to check what the approximate size of the pupil is. Some technologies can measure your iris – the portion of the eye that is colored. These measurements will determine the contact lenses that have the best fit in your eye.
Tear film evaluation assesses if you have the ability to produce tears or if you have a dry eye. It is done by inserting small paper underneath the lower eyelid for 5 minutes. Having severe dry eye condition is not suitable for contact lens wear. There are special contact lenses for dry eyes that take away the discomfort of mild dryness due to contact lens wear.
Evaluation of contact lens fit is important to know what is comfortable and what provides an excellent vision. Contact lens prescription is given based on the data measurements gathered. An annual eye exam is recommended to monitor eye health.