They’re big, they can be difficult to fit and they’re not cheap, but are scleral contact lenses the ultimate solution for clear, comfortable vision?
Read on to find out what they are and when you should consider them.
What are scleral lenses (and what’s a sclera?)
Your sclera is, quite simply, the white of your eye. It’s the strong, spherical rubbery layer that makes up the majority of the surface of your eyeball. The other surface is your cornea – the small, clear window at the front of your eye, where you can see your iris – the coloured part of your eye.
Most contact lenses sit on your cornea. They alter its shape to provide clearer vision.
In dry eye disease, the cornea can become hypersensitive and experience pain with the slightest touch.
In keratoconus, the cornea is thin, and bulges outwards. Soft lenses that sit on the cornea don’t usually provide clear enough vision. Hard (or RGP) contact lenses provide much clearer vision but can often be uncomfortable as they sit directly on the highly sensitive cornea.
After a corneal graft (also called a corneal transplant) your cornea is a different shape and can be very irregular and it's almost impossible to wear a corneal lens - hard or soft.
Scleral lenses are larger than your cornea and straddle it, so they only touch the far less sensitive white of your eye – your sclera. Provided they are correctly fitted, they are usually very comfortable AND they provide clear vision – what’s not to like?
Why are they so expensive?
Ah! So, there are some drawback to scleral lenses. This contact lens option is the most expensive option and is usually reserved for more severe cases of cornea disease, including keratoconus and dry eye syndrome.
Your contact lens specilaist will usually exhaust the easier and less expensive options first.
But if you’ve tried everything and are still struggling, scleral contact lenses can literally be life-altering.
In the hands of an expert, these lenses really do give people back their quality of life by providing clear and comfortable vision.
How are they fitted?
In the hands of a specialist contact lens practitioner and with access to the right technology, these lenses can be successfully fitted within a couple of visits – sometimes less.
First, a scleral map of your eye is generated using a special scanner.
This unique ‘mould’ of the front of your eye is then sent to the lap to create a bespoke contact lens that is an exact match for your eye. The inside of the lens fits the surface of your eye, no matter what the shape.
Allowances need to be made for your tears to circulate beneath the lens. The more experienced the contact lens specialist, the more streamlined the whole process becomes.
Advantages of Scleral contact lenses:
- Better vision
- Far more comfortable than corneal lenses
- Create a moisture chamber around the eye, providing relief for dry eye sufferers
- Stable in the eye – don’t fall out during sports etc
- Easy to insert and remove – once you get the hang of them
- Once correctly fitted, much quicker to adapt to than RGP lenses
And the downside of sclerals…
- More expensive than other contact lens options (at $1600-1800 per lens)
- The larger size of these lenses can be intimidating for some people
- Difficult to fit successfully – you must see a contact lens expert who fits them regularly