Questions about Sclerals

[James_Ldn]

Hey all,

After trying most lenses known to man, I'm thinking of giving the large 23mm scleral lenses (of the Ken Pullum variety) a try. I know that there are a few people on here who wear these and I'm hoping they could offer some advice on a few questions I have.....

1) Other than comfort, are there any advantages of the larger Scleral lenses over the smaller versions?

2) Do scleral lenses 'mould' the eye in the same way that RGP lenses do? I'm a bit concerned that they do for three reasons:
[*] From past experience I've worn lenses (like hybrids) which mould your eye so that when you take them out at the end of the day, they can leave you with vision that's more distorted than usual. I only have mild KC and can see reasonably well with no lenses in, so I don't want to be in a position where I'm a lot more limited with my lenses out.
[*] I know that people who wear RGP lenses long-term and then try switching to soft lenses have difficulties with changing prescriptions as the eye 'de-moulds' over several months. Does the same apply if you move from Sclerals to soft lenses?
[*] Also, when I have my annual topographies done I have to leave my soft lenses out for a week beforehand. For sclerals though, does it only take one week to de-mould? As I say, I've seen it mentioned on here that RGP lenses take a lot longer, so I wonder if it's the same for Sclerals.

3) Do Scleral lenses take any longer to manufacture / order than other lenses?

4) Are there any people here who manage to wear Scleral lenses for 12-14 hours each day, 7 days a week with no problems? (hopefully yes!)

5) Is Ken Pullum the only one who fits the larger Scleral lenses? I can't seem to find anyone else who does them.

Hopefully there are some people on here who can help, many thanks in advance!

James.

[GarethB]

Don't wear sclerals, but I have had a large amount of conttact with people who do so my answers are based on what I have learnt from them. Others with sclerals may disagree, but then we all have different experiences of lens types. I swear by soft lenses for most stages of KC, others swear by RGP's and I know a moderator here who swears by sclerals.

1) Unsure about the comfort issue, but it is easier for the scleral to completly vault the KC cone, especially if it is of center. Disadvantage reported while they get used to them is the size and being able to put them in without airbubbles and cost of the saline to fill the lenses which some NHS authorities provide on prescription, others don''t.

2) Sclerals completly vault they eye so I beleibve shouldn't mould the eye, if they do probably no more than a soft lens, an optomotrist is best to advise here. Solid plastic touching the cornea will have a dgere of moulding based on shape so it can squeeze the cornea to mould it or push down to flatten the cornea. To date I haven't encounetred anyone that has gone from a scleral to a soft lens although I know people who have tried both and settled on one. Leaving lenses out before topography just might be the choice of your eye care practitioner, I haven't heard of it before. In the past 10 years of recent lens wear I have always been asked to attend appointments with lenses in and the topography has been done within minutes of taking my lenses out. Going from a day of good vision to no lenses most people report more distorted vision compared to when they woke up with no lenses. In some cases this is down to the lens type because of moulding, in others where there is little to no moulding it is more a brain thing being a bit slow to switch back to compensating to limited vision. When I take my soft lenses out, it takes between 5 - 15 minutes to go back to compensation mode, for some reasn the brain is better at switching to seeing proplerly mode, but is probably the way the brain is wired.

3) This is one for an optometrist, but from my understanding the biggest issue is available appointments at the hospital for themt o fit the lens once they receive it.

4) I am sure there are people who manage lenses all day every day, but I do know a number of peole outside the forum who wear their sclerals for as long as I wear my soft lenses beyond the 14 hour period. Again we are all different so it is very much a case of see how you get on if you choose this option.

5) There are other manufacturers, but Ken is probably the best know authority on all things scleral in the Uk.

My KC is in a post graft eye and is concidered to be quite bad. The terms mild, moderate and severe are all relative with a lot of grey inbetween each classification so I go more on what people can see and how thin the cornea is. With no lenses I can't even see the eye chart but with my Kerasoft IC I can get 6/5 (6/6 on a bad day) and wear them all my waking hours which averages at 16 hours and if I am travelling on business as long as 20 hours in all sorts of conditions.

[James_Ldn]

Leaving lenses out before topography just might be the choice of your eye care practitioner, I haven't heard of it before. In the past 10 years of recent lens wear I have always been asked to attend appointments with lenses in and the topography has been done within minutes of taking my lenses out.

Thanks for your reply Gareth. Post CXL, whenever I've had a check up to ensure the progression of KC has stopped, I've always been told to leave my lenses out for a week beforehand. And this has been both through the NHS and privately, so I assumed it was standard procedure! I'm just a bit concerned that for harder lenses, one week might not be enough.

Going from a day of good vision to no lenses most people report more distorted vision compared to when they woke up with no lenses. In some cases this is down to the lens type because of moulding, in others where there is little to no moulding it is more a brain thing being a bit slow to switch back to compensating to limited vision. When I take my soft lenses out, it takes between 5 - 15 minutes to go back to compensation mode, for some reasn the brain is better at switching to seeing proplerly mode, but is probably the way the brain is wired.

I have the same with the Kerasoft lenses I'm using at the moment, it takes about 10 mins for my vision to go back to 'normal' when I take them out. However, in the past when I've used hybrid lenses, they must have moulded my cornea to some degree as it took about 12 hours to return to normal, once they were taken out. To me, this was really unacceptable as I didn't like not being able to see at all without my lenses. As my KC is quite mild, I still do get about with no lenses in and I don't want to lose this freedom.

With no lenses I can't even see the eye chart but with my Kerasoft IC I can get 6/5 (6/6 on a bad day) and wear them all my waking hours which averages at 16 hours and if I am travelling on business as long as 20 hours in all sorts of conditions.

Yours is pretty much the opposite of my case! Without any lenses I can get down to about 20/30 with both eyes (albeit a more blurred 20/30 than a 'normal' person would get). But despite only needing a relatively small improvement to get down to the 20/20 line, every lens I try seems to get me only as far as the 20/25 line (again, with blurriness), which is frustrating. I think I must have a high degree of 'Higher Order Aberrations' which the lenses just aren't correcting.

[James_Ldn]

Is there anyone who wears Sclerals who might be able to offer some advice here? Would be very grateful if so.

(This forum seems very quiet lately!!)

[Libby]

Hi there - sorry I can't offer any advice on the sclerals but I totally agree with your last,comment. The,forum seem,unusually quiet. Where is everyone.

Libby

[Anne Klepacz]

Hi James,
I've never worn sclerals either, but this is an extract from a talk that an optometrist gave at one of our meetings a few years ago and which may answer some of your questions -

"Scleral lenses These are the largest diameter lenses with an average diameter of 23mm (as against 9mm for a corneal lens and 14 for a semi scleral). It is a sealed system, with no tear exchange from the outside and designed to vault the cornea, so any size or shape of cone can be fitted. The lens rests on the sclera (the white part of the eye) so there is no lid sensation.
Sclerals were actually the very first contact lenses made 100 years ago (when they were known as haptic lenses). The first sclerals were made of glass and used a mould. In the 1930s PMMA lenses were produced, but again these had to be hand made and usually had fenestrations to let in oxygen. The introduction of corneal rgps in the 50s meant that sclerals were hardly used until the development of gas permeable sclerals in the 80s made them an option again. Gas permeable scleral lenses do not need fenestrations as oxygen comes through the lens. They are also no longer hand made, with preformed fitting sets available for the practitioner.
Scleral lenses can also be used post graft, and the fact that they do not touch the cornea has led to trials of early fitting of sclerals 3 months after a corneal graft – a point when other lenses cannot be used.
Advantages of scleral lenses include the fact that their size makes them difficult to lose, they are robust and easy to maintain, can fit any corneal topography, produce no lid sensation and are easier to handle than small corneal lenses. Disadvantages are their intimidating size, a sensation of bulk in the eye (more of an issue if a sceral is worn in only one eye) the need to fill the lens with saline before insertion, reduced oxygen available to the cornea and surface wetting issues. If the sclera is uneven, there may be scleral compression."

Libby - one reason the forum is quiet is that we had to stop automatic registration in mid December, so anyone new wanting to register on the forum has to contact us. (This was because we were getting thousands of spammers joining up and flooding the forum with spam). Sadly it seems to have put newbies off joining so we're not getting the usual volume of new forum users.
Anne

[sky1]

Hi James,

I wear sclera's and have done for about 11 years now, I recently had a graft so only one of my eyes has a scleral now but hopefully I can help!

I have never tried the mini sclerals so can only comment on the larger ones. Ken Pullum originally fitted me with my lenses at Moorfield's and since then either himself of one of his recommended colleagues have refitted me when my prescription or lens size needed changing. Ken's company Innovative Sclerals make mine but there are other companies out there, I'm not sure of who they are but I am sure a quick google would find them and I know new materials are being developed.

I don't wear my lenses anywhere near as long as I used too just because I want to give my eyes as much rest as possible. However when I did (especially at university!) on a good day I could wear my lenses for 16 hours + a day, I wouldn't recommend this though. I am/was partially sighted without my lenses so had no other choice in order to live as normal a life as possible. Everybody is different and it depends entirely on lens fit, tolerance etc so you wouldn't know until you tried them. My eyes are different everyday so they tell me when they are ready for my lens to go in if that makes sense?! I have become much more attuned to how my body feels which I believe is very important especially when it comes to our eyes.

When I take my lens out I can initially notice a de-moulding effect if you like (where my vision would be slightly better than normal without a lens) but this is temporary and if you have good fit/corneal clearance it should not be a problem. For upcoming topography appointments I have had to leave my lens out for two weeks minimum. Not sure what I'd do if I had to leave them both out though!

I hope this has helped in some way, any more questions please just ask.

Best wishes

Sarah

[James_Ldn]

Thanks Sarah and Anne.

For my NHS appointments I don't go to Moorfields and I'm reluctant to try given the waiting times for appointments! Might have to just buy them privately, even though they are very expensive.

Sarah, I think you're right that everyone reacts to lenses differently, so I might just have to give them a try and see how things go. Normally my eyes don't get too dry and I find lenses quite comfortable all day, but I haven't worn lenses as 'hard' as sclerals before so they might work out differently.

If I do get good vision from them, I'm just hopeful that I can wear them for long enough to last a working day and that the 'spectacle blur' isn't too bad when I take them out in the evening.

Interesting that you say you have to leave your lenses out for at least 2 weeks before a scan. My consultant has always said one week, but I need to check with him if that should be 2 weeks if I change from my Kerasoft lenses to sclerals.

...by the way if anyone else who wears Sclerals can offer their experiences that would be very helpful!!

[GarethB]

Interesting that you say you have to leave your lenses out for at least 2 weeks before a scan. My consultant has always said one week, but I need to check with him if that should be 2 weeks if I change from my Kerasoft lenses to sclerals.

For some people, this would mean that thye would be unable to work / study at all. When I had a reaction to the RGP lens material I was in the hospital every two to four weeks; so if I had to wait two weeks with no lenses for a scan I would be unable to travel to / from work (no public transport). I really think many eye care professionals have no idea what it is like for us.

[sky1]

You don't have to go to Moorfields, I know Ken has trained some NHS professionals to fit them. You could try getting in contact with him or his company to possibly find out recommended fitters? Where in the country are you based if you do not mind sharing?

I'm not sure about vision distortion but something you could check when you find an optician.

I am very fortunate to tolerate my scleral, I have had my ups and downs but my scleral takes me from being 'socially blind' to driving standard even just for a few hours a day I am so very grateful.

All the best

Sarah