Contact lenses are a popular alternative to prescription glasses for many people. Many people want contact lenses as an occasional accessory, while others want to completely replace their glasses. There have been so many advancements in the technology of contact lenses as a result of which patients now have a wide range of options, and almost all patients of any age can be fit with contact lenses. A contact lens is a medical device that is FDA approved. Therefore, it's important that they are taken care of properly and responsibly. You should be careful to never purchase contact lenses without a prescription from an eye doctor, which is both illegal and very unsafe. Make sure to go to your eye care provider to receive a proper contact lens evaluation so that they can determine what type of contact lens is best for you.
How is a contact lens exam performed?
Contact lens examinations usually start with a comprehensive eye exam, which involves checking your vision, your refraction and what kind of glasses prescription you need. After that, your ocular health will be examined by looking at the front and back parts of your eyes. Based on the curvature of your frontal part of the eye and different measurements, your eye doctor will determine what your contact lens prescription should be. Therefore, it is important to understand that your glasses prescription and the power in that prescription are different from your contact lens prescription. Not only do contact lenses have a prescription power, but also what is called a base curve, and recommended diameter of the lens. All of our eyes have unique front surfaces, so not every lens will fit the same way on every patient. There isn't one lens that fits all. That's why it's important to have a contact lens examination to determine what will be the best fit for your eyes.
Once your eye care provider places the contact lens on your eye, they will check your vision and determine if you need over-refraction or if the power of the lens needs to be adjusted. A microscope is then used to examine the fit of the lens and how well the contact lens moves on your eye. It needs to fit comfortably and not stick too tightly to the eye. If that's the case, they may need to make the contact lens a little flatter in curvature. They ensure that the contact lens has good coverage of your eye and will be well centered on your eye. Furthermore, they ensure the primary gaze and the upward gaze are both well-moving. All these things need to be considered. Additionally, they take into account what type of contact lens is best for you, such as whether you should use a daily contact lens, a biweekly contact lens, or a monthly contact lens.
Are improper fitting contact lenses dangerous?
Poor fitting contact lenses can result in a host of complications including:
- Corneal abrasions
- Infections
- Ulcers
- Lack of oxygen to the eye
- Developing a permanent intolerance to wearing contact lenses
While most cases are minor, wearing contact lenses that do not fit correctly to your eye can result in severe complications and in certain cases even permanent vision loss.
What options are available for contact lenses?
Depending on your prescription, an eye doctor can either recommend soft contact lenses, hard contacts, or specialty (medically necessary) contact lenses.
Soft contact lenses: Generally speaking, soft contact lenses feel more comfortable on your eyes, and there are several options to choose from. It's possible you'd receive a prescription for toric contact lenses, which are used to correct astigmatism, or you could get a prescription for multifocal contact lenses, which correct both distance and near vision. Toric multifocal contact lenses are worn by people with astigmatism who also need to see clearly up close and far away.
Hard contact lenses: If you have a very high level of corneal astigmatism, or if you have an eye condition like keratoconus, then a soft contact lens won't fit well on your eye, and you won't have great vision. You may then be advised by your eye doctor to use hard contact lenses. Hard contact lenses include scleral lenses, rigid gas permeable lenses, or orthokeratology lenses.
