Everyone should know what contact lenses are and need no introduction to what they do. There are different types of contact lenses and they are grouped into 2 broad categories: soft and hard lenses. A contact lens is a great choice for the majority who need vision correction. In fact, it is a great alternative to the "traditional" eyeglass.
To list, contact lenses can help to correct:
- Hyperopia, also known as long-sightedness
- Myopia, also known as short-sightedness
- Presbyopia - inability to focus due to old age
- Astigmatism - focusing problem due to different eye curvatures in different directions/axes
In my years of practice, I have advised many patients regarding the correct choice of contact lenses. Hence, I wrote this article to help those who are unsure of which type is more suitable for them.
Read on to find out more!
Why do people consider contact lenses?
It is just a personal preference for most. In fact, many people who request for contact lenses do not like how they look with glasses on. Besides, glasses can also be a hindrance to your lifestyle .
If you identify with the above, contact lenses can be a good alternative. However, do note that lenses must be prescribed by an optometrist or eye doctor. Therefore, if you are planning to get your first pair, do get a consultation!
Types of contact lenses
Generally, there are 2 types of contact lenses: soft and hard lenses. Both types have their own differences. With that said, each type of contact lens is aimed at tackling different types of eye problems.
Soft Contact Lenses
Soft contact lenses are made of gel-like, water-containing flexible plastics called hydrogels, allowing oxygen to reach the cornea. Thus, it is a lot more comfortable. It is also easier to fit soft contact lenses .
Easier to fit and adjust lenses.
May dry the eyes more, especially with higher powers/thicker lenses.
More convenient to use. In fact, there are more disposable options available.
Slightly higher rate of infection compared with hard lenses.
Takes a few days to adapt.
Frequently replaced lenses (e.g. daily disposables) can cost a lot in the long run.
Stays in place better.
Hard Contact Lenses
Meanwhile, there are also hard contact lenses. It is also known as Rigid Gas Permeable (RGP) contact lens. Being more durable as compared to soft lenses, it is more resistant to deposit buildup and also lasts longer. It provides a new, completely smooth and evenly curved surface over the cornea to focus light and, hence, giving a clear vision. Generally, it is less expensive in the long run as it does not have to be replaced as frequently as soft lenses .
Very durable. In other words, easy to care for.
Easily dislodged from the centre of the eye.
Less drying for the eye.
Can cause eye pain if dust/dirt gets into the eye and is trapped under the lens.
Retains its shape.
Often takes a long time to adapt.
Particularly useful for high spectacle powers.
Offer a clear and crisp vision.
Corrects low degrees of astigmatism automatically without requiring special toric lenses.
There are monofocal and multi/bifocal versions of both soft as well as hard contact lenses.
Specialised Contact Lenses
Besides the above, there are other types that serve other purposes:
- Decorative cosmetic
- Myopia control contacts
So, does that mean contact lenses are suitable for everyone?
Unfortunately, no. Contact lenses are not meant for everyone. Hence, you may not be able to use contact lenses if you:
- have dry eyes
- suffer from allergies
- have an underlying illness such as diabetes, arthritis
- work around chemicals
- are in a dusty environment
Thus, one should consult an optometrist or eye doctor to find out whether contact lenses are suitable for you.
In fact, contact lenses are not risk-free if care instructions are not followed.
In short, here are the possible risks :
- Keratitis - infection of the cornea 
- Growth of new blood vessels onto the cornea
- Scratches on the cornea
- Allergies affecting the eye
Therefore, patients should flag out when they experience:
- Blurry, red, itchy or dry eyes,
- Uncomfortable fitting of lenses,
- Pain around the eyes.
In brief, here are some key points that you should take note of:
- Do not buy contact lenses without prescriptions. In other words, only buy them from professionals.
- Proper hygiene is key. Always follow instructions for wearing, rinsing and disinfecting your lenses.
- Never expose contact lenses to water not recommended by your optometrist. For example, tap, bottled or distilled water.
- Finally, be sure to tell your eye doctor if you experience any symptoms of eye irritation or infection .
If you need more information, you should submit your questions here.
Dr Inez Wong is the Director of Paediatric Ophthalmology and Strabismus Service at Eagle Eye Centre. Besides that, her special interests are in strabismus management and surgery in adults and children as well as paediatric ophthalmology, specializing in a range of eye problems in children.
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3. Center for Devices and Radiological Health. Advantages and Disadvantages of Various Types of Contact Lenses. U.S. Food and Drug Administration.
4. Dart JK, Stapleton F, Minassian D. Lancet (London, England). Contact lenses and other risk factors in microbial keratitis.
5. Contact Lens-Related Eye Infections. American Academy of Ophthalmology.
6. Center for Devices and Radiological Health. Contact Lenses. U.S. Food and Drug Administration.