Is there an optometric criteria for soft lens/glasses?

[jay87]

Hi All

I am currently wearing an RGP in my right eye which is -8.75D and an old prescription soft lens in my left eye which is -4.50D which isnt correcting my vision enough. I am wondering whether to get a new soft lens fitted for the left eye or another RGP. I would prefer the soft lens comfort but want good vision. I was wondering, is there a max diopters that can be corrected via soft lens/glasses? Or is the corneal topography and profile of astigmatism a greater factor?

Thanks

[Andrew MacLean]

Jay

You ask an intriguing question. I guess the answer will be a bit of both.

The problem with keratoconus is that it is what one of our optometrist members has called "a bespoke condition"; no two of us are alike and our eyes sometimes defy the normal optometric definitions.

That said, there are new soft lenses and new lens materials that make old assumptions redundant. I think that there may be a member along in a moment or two who has more experience of new lens development and who can report considerable success in prescribing and fitting soft lenses to eyes with quite advanced keratoconus.

I should also say that I was never able to wear soft lenses. It is not that they provided me with inadequate correction but that they were always extremely uncomfortable, probably due to my tear film breaking up and evaporating very quickly.

Every good wish.

Andrew

[GarethB]

As an ex RGP lens wearer and now on soft lenses for KC, I have found them to be far superior than any RGP lens.

My left eye is my better eye and a standard soft lens won't correct enough as greater than -4D, but there are some special order standard soft lenses that will go higher but I don't know many high street optoms that supply these.

About 4 years ago I was having trouble with RGP's and could only wear them for an hour each day despite the left eye being easy to fit, the right was problematic to get an RGP to fit. With the soft lenses it has been easy to fit lenses to both eyes. Can't remember my prescription, but once I get back to the UK I will be able to say, but 8.75D is easily corrected with soft lenses fo KC. Having said that, tehre are other factors that determine the best lens but I diagree with optoms making sweeping statements as there are always exceptions to the rule.

I was told soft lenses would never work for me, yet I now know so many people like me that I no longer think those of us neededing soft lens are the exception to perceived wisdom / rules. My vision is better than with RGP's I wear my lenses for longer, no longer light sensitive, visual acquiety is far better (6/5 in soft, 6/9 in RGP).

[Lynn White]

Hi Jay,

Gareth has answered most thoroughly. Just to add that that, most lathe cut soft lenses can fit a very wide range of powers. Its disposable lenses that have a limited power range.

KeraSoft, for example, has a range of +/- 40.00 dioptres sphere and up to 15.00 of astigmatism.

Lynn

[jay87]

Thanks very much for your replies everyone

Have gone with another RGP for the time being

Will definately consider Kerasoft in the future though, as I can't wait to rub my eyes of an eve after wearing them all day!