Different Types of Lenses

[Ben]

Hello,

I was diagnosed with KC in 2001 and prescribed softperm lenses, the ones with the hard centres and soft outers. The vision I got with these is very good but the pain was excruciating! especially if the soft outer tore (which was often the case).

I was recently prescribed RGP lenses which have been great, except the lens in my right eye keeps falling out.

I'd like to ask if anyone knows of a larger RGP lens, (maybe about the size of a softperm?).

I've tried sclerals and have now been offered semi-sclerals.

There must be a hard lens available thats big enough not to fall out withough going into scleral territory?

I would be so grateful for any advice.....

Kind Regards...

[GarethB]

Hi Ben,

Welcome to the forum.

Unfortunatly KC is not as simple as fitting a larger lens. This is because depending on the steepness of the cone, even a large lens can slip down the cornea and leave an edge exposed making it prone to being blinked out.

Lenses can be made to effectivly grip the cone to help stop them sipping down, but these can be uncomfortable as they have a larger contact area on the cornea and can cause scarring if the fir is too tight.

Some people use piggy back lenses. A soft lens that sits directly over the cornea and an RGP lens that sist on top. The RGP can then in effect grip the soft lens and hold it in a better position which may reduce the number of occurances where the lens is blinked out.

Lens fitting is as much an art as it is a science.

Hope this helps.

[Ben]

Thanks for the reply!

I suppose all I can do really is ask to try the lenses as you suggest.

Best Regards,

Ben

[Andrew MacLean]

Ben

Yes, lenses that keep falling out suggests that there is a problem with the fit. I think we have all lived with this at one time or another.

It may be that your fittier needs to try a steeper fit. Go back and tell them what is happening. don't give up on RGP's too early. there are down sides as well as advantages with differend lens types.

Welcome to the forum. It is always good to know another fellow sufferer

Andrew

[Sandi M]

Hi Ben,

I also wear softperm lenses, which have been, on the whole, successful. I also get a tear in my outer lens occasionally and normally have tto have them replaced about every 6 months

The only downside is the pain I get in my eye.

Good luck finding something the works.

Sandi

[Christine Wright]

Hi there. To answer your question directly - there is a GP lens which is 14mm in diameter, the same diameter as a soft lens or soft perm. It's called a SLIM lens (short for Semi Limbal). It's very useful if you can't get a standard GP lens to stay in.
Obviously, I have no idea if this is the best lens for you, but it's good to know that there are so many lens designs on the market....

[GarethB]

Ben,

Just had a look at your original post regarding the lens just dropping out. I can make my right lens fall out if I want yet it is the best fit.

Driving and move my eye to the extreme left or right I can blink the lens out! Now I turn my head slightly so my eyes are no longer at the extreme left or right, no more lens falling out.

Save blinking the lens out for when I want to remoe it. As long as my eyes are not dry I can open my eye wide and blink sharply and out pops the lens.

The only other time my lens is likely to fall out is if I am playing a particularly fast computer game (which is not often) anfd the rapid eye movement and wide eyes staring at the TV, when I do blink the lens can be blinked out. As it is only a game I am not too botherd. I can be quite quick at pausing a game before I loose a life!

I know some whoe lens become loos if their eye and lens drys out. For me if my lens and eye dry out, the lens irritates and sticks like a limpet to the cornea.

Is there any particular activity you are doing when the lens just pops out?