Silicone hydrogel contact lenses are advanced type of contact lenses which allow more oxygen to pass through them and reach the cornea, thus keeping your eyes moist and comfortable. They are known to be far better than regular ‘soft’ gel lenses, which are basically just hydrogel lenses. While both of them share similar general characteristics, silicone hydrogel lenses are known to allow more than five times the oxygen regular hydrogel contact lenses do. When dried out, both become hard and brittle, but upon dipping in a contact lens solution, they retain their soft characteristics. So what exactly are silicone hydrogel lenses and why should you consider buying them? We tell you all you need to know!
Some of the most popular contact lenses used around the world, for both regular and sensitive eyes, are actually silicone hydrogel lenses. Since they keep your eyes more oxygenated and moisturized, they work well even for sensitive users. Note that they’re called ‘silicone’ hydrogel lenses and not ‘silicon’ hydrogel lenses, both are completely different materials. Silicon is used in computer chips and such, while silicone is used in contact lenses as well as breast implants.
Silicone hydrogel lenses have a variety of benefits, the most significant of which, as we already mentioned, is the ability to let in far more oxygen than all other types of contact lenses. In general, people stay away from contact lenses because it gives them an ‘enclosed’ feeling and red, itchy or dry eyes, and these are the exact problems that silicone hydrogel lenses address. Hypoxia, the name given to a condition when there’s a lack of enough oxygen, gives rise to problems such as corneal swellings, eye infections and bad vision.
A lot of problems related to eyes occur simply because a fair number of contact lens users don’t follow a proper maintenance or replacement schedule. Smothering your eyes in improperly kept contact lenses for long can lead to a large number of problems, and so silicone hydrogel lenses were developed to combat them. Since they are more permeable, issues related to hypoxia were greatly reduced, which was what caused most of the problems in the first place.
The material itself is much more versatile than others, and is also used to make specialty contact lenses. By specialty contact lenses, we mean lenses meant for people with astigmatism or special eye conditions. So, this opened up the possibility of bifocal contact lenses, as well as contact lenses for people with unconventionally shaped eyes.
In general though, the benefits of silicone hydrogel contact lenses are as follows:
- Enhanced comfort, because of the higher oxygen permeability
- Allows for extended wear
- Allows continuous wea
Silicone hydrogel lenses are just a broad term though, and actually include multiple materials and generations, such as galyfilcon, senofilcon, enfilcon and comifilcon. Again, each type or material has slightly different characteristics, so it’s always better to consult an expert to find out whether they’d be suitable for your eyes and usage. Most extended use lenses are silicone hydrogels, so that must give you a fair idea of how versatile they are.
Apart from the usual consultation, you should also double check what contact lens solutions you’d be using with silicone hydrogel contact lenses, because not all solutions play well with them. That’s not all either, it has been found from studies that silicone hydrogel contact lens users tend to be at a lower risk of severe keratitis, but seem to contract non-severe keratitis more frequently. This risk is of course increased for both wearers and non-wearers if they decide to keep wearing their contacts overnight.
Overall, silicone hydrogel lenses are known to reduce redness, dryness and itchiness, but a very small number of users experience these problems even with their use, as an allergic reaction to the silicone content. Lipid buildup also causes this, so as we mentioned earlier, getting a checkup prior to shifting contact lens types or materials is always justified.
Finally, there’s the matter of cost. Silicone hydrogel contact lenses are slightly more expensive than regular hydrogel lenses, so price conscious consumers might have to think twice before picking up a pair. Otherwise, if you have no allergic reactions, of course, and can afford them, silicone hydrogel contact lenses are the way to go!
Image Credits: contactlensupdate.com, alicelens.com, optometricmanagement.com