piggy back lenses and fogging up

[Paul Harris]

At the moment I am using Hybrid GP lenses from Jack allan with a Acuvue Oasys with Hydra clear plus soft lens underneath (piggy back) is there a thinner lens I could wear under the GP that any one can recommend at the moment I get them fogging up a bit and find the 2 lenses in my eye a bit bulky, or is that what is expected when using the piggy back system ?

[rosemary johnson]

Hi.
I'm piggybacking under sclerals.
I don't find the combination particularly bulky - but then, if you've ever seen a scleral, you'll realise that the size of a soft lens underneath doesn't add much to the size of a scleral!
I do get them fogging a bit - in the sense that the vision is no longer good enough for reading well before the comfort has deteriorated to the point where I need to take them out due to discomfort.
I don't know why this is, or if it's "normal".
Rosemary

[Asif]

I had the same problem with the piggy back method when I was using small corneal RGPs on top of hydrogel lenses. It was because there was little oxygen getting to the cornea because of the reduction in oxygen permeability from wearing two lenses rather than one. My vision would become very foggy/misty the lens would dry out after a few hours.

If your CL clinic get a few lenses from Jack Allen you may want to try their new lens design 'flex edge'. They are similar to soft perms where the edge of the lens is thinner making it flexible and are totally made from RGP materials rather than a soft skirting fused to a RGP centre. Is this the hybrid lens you are currently wearing.

[malcolm]

hi
try using the proclear compatable by cooper vision it is a very thin lens and has a high oxygen transmission it has made a great improvement to my wearing time
malcolm

[David Bennett]

Paul,
It/s most likrly the oasys whgich is smearing up due to it;s increased mucin deposition. It's THE number one lens though due to it's huge o2 permeability and flux. (I declare as sort of "advisory" interest being on the Optometric UK advisory panel to Johnson and Johnson) .

My plan wd be:

1) Leep your lids Very clean (hot compresses and use "Lid Care" (ciba) on a daily or 2x daily basis)
2) If you clean the oasys lens use either Optifree or Regard
3) If no better go see your contact lens practitioner!

David