The market is now flooded with different types, shapes, and colors of contact lenses for your convenience, from silicone hydrogel contact lenses to hybrid ones; pick your choosing according to your condition and preference.
But first, make sure you are informed about each kind, and consult a doctor to prescribe the right fit for your eyes.
What are Silicone Hydrogel contact lenses?
You hear the word “Silicone”, and the mineral found in dust and sand immediately crosses your mind, right! Don’t get confused though, that mineral is “Silicon”.
Contrary to this common misconception, silicone hydrogel contact lenses are actually made of a synthetic gel-like plastic substance including Silicon, Oxygen, Carbon, and other elements. They are soft, flexible lenses that get rigid when dry.
Hold on a moment! Some of these elements are hydrophobic, meaning they “hate” water and don’t bind with it. Isn’t that a big problem for contact lenses to have? Well yes. Yet, manufacturers developed several solutions, including:
- Using a gas plasma reactive chamber during manufacturing to make the contact lens’ surface wettable.
- Adding a wetting agent to the formula, like PVP.
- Wrapping a Silicone core with an essentially Hydrogel-like exterior.
Silicone Hydrogel contact lenses offer you great benefits, and even though they still carry some rare risks, manufacturers are working on eliminating them. From your side, proper maintenance is sufficient to avoid these risks.
Silicone Hydrogel Contact Lenses VS Hydrogel Contact Lenses:
It is a medical fact that the cornea of the eye does not contain blood vessels to deliver Oxygen; instead, it feeds off the Oxygen in the surrounding air. Hydrogel lenses have low Oxygen transmissibility, putting you at risk of cornea suffocation, an issue that gave rise to Silicone Hydrogel Contact Lenses.
Since their first use, researchers have been working on and succeeding in making Silicone Hydrogel contact lenses more efficient to meet the cornea’s requirement of Oxygen, whether as single or multi-use contact lenses.
Silicone Hydrogel Contact Lenses and Oxygen:
What is cornea suffocation exactly? How do you know it is happening to you?
Well, if you tried wearing Hydrogel lenses for an extended time or overnight, then you might have developed corneal hypoxia, also known as Oxygen Deprivation Syndrome.
This condition happens when your cornea is unable to get adequate Oxygen from the atmosphere. So, it starts to swell and abnormally grow blood vessels in an attempt to correct the issue, a process known as neovascularization.
The symptoms are somehow similar to an infection, your eyes swell and turn red, and your vision fluctuates. Don’t mistake the two conditions, though! And consult a doctor for treatment.
On the other hand, there is sufficient evidence to support Silicone Hydrogel contact lenses’ benefits in minimizing the risk of developing Oxygen Deprivation Syndrome thanks to their high oxygen permeability.
Silicone Hydrogel Contact Lenses and Infection:
Silicone Hydrogel contact lenses indeed improve Oxygen permeability. However, Oxygen is not the only risk factor in developing a bacterial infection; other factors include:
- Changes in the surface of the cornea.
- Tear film stagnation.
- Turnover of corneal cells induced by extended contact lens wear.
- Wearing contact lenses overnight, the risk of infection is six to eight times higher in such cases.
- Improper cleaning and handling of contact lenses.
Due to the wide range of infectious factors, we can’t guarantee that Silicone Hydrogel contact lenses can eliminate the risk. However, they do have a role in reducing it, especially when you follow the specialist’s recommendations on how to use and maintain your contact lenses, which should be sufficient for the risk of infection to subside.
Silicone Hydrogel Contact Lenses and Allergic Reactions:
Some contact lens wearers thought they were having allergic reaction symptoms, like redness, itching, dryness, and discomfort. However, later on, researchers attributed these symptoms to two things:
- The hydrophobic properties of Silicone, which researchers corrected with several techniques, as we mentioned above.
- Increase sensitivity in the cornea due to Silicone Hydrogel contact lenses high Oxygen permeability.
There is little to no evidence or FDA approved case studies of Silicone causing allergic reactions among wearers.
Read more: Are contact lenses biodegradable ?
Silicone Hydrogel Lenses Complications:
When you follow the specialist’s schedule and guidance, you should not experience any lenses-related complications. However, when you were them for prolonged times or overnights, some problems may occur, including:
- Reduced comfort.
- Contact Lens Induced Papillary Conjunctivitis; CLIPC, which is a mechanical irritation caused by poor lens fit.
- Contact Lens-related Acute Red Eye; CLARE, which is an inflammatory reaction to bacteria that takes place when you wear the lenses overnight.
Benefits of Silicone Hydrogel Contact Lenses:
Silicone Hydrogel lenses overcame many risks you may encounter with Hydrogel lenses and offered many benefits:
- High Oxygen permeability; reduce Hypoxia symptoms.
- Lesser discomfort and irritation.
- Extended and prolonged use; longer durability.
- Lesser risks and complications.
- Variety of colors and designs for daily use.