Two Contact Lenses You Might Not Know About

This is a post directed to non-eye-care-practitioners, but all are welcome anyway. There are two lenses I've worked with (one for years, another I'm just beginning to work with) that most people have probably not heard about, and I'd like to introduce them.

First, the one I've been using a while: it's called the SynergEyes, and it's a true "hybrid" between a soft and hard lens. It's a soft lens with a hard center, or a hard lens with a soft flange (or "skirt"), depending on how you look at it. It's the size (diameter) of a soft lens, which is why it feels comfortable. A large lens will have less interaction with the inside of the lid, which is what causes smaller, hard lenses to be less comfortable.

Now when I say "hard center," let me be a little more precise. I'm really talking about a "rigid, oxygen-permeable" center, and these things transmit a whole lot of oxygen. A bit of history here: the SynergEyes is the third hybrid lens ever produced, and the first two (the Saturn and the Soft Perm, both of which I fitted in their day) were problematic mainly because they reduced the oxygen getting to the cornea, and because they tended to break at the junction between the soft and rigid parts. SynergEyes has solved both of these problems (bless their hearts!)

I use these lenses when soft toric ("astigmatic") lenses fail, which happens occasionally, and usually because the vision isn't good enough. Soft toric lenses will blur the vision if they rotate on the eye, and this can be quite a problem if you're trying to hit a 90 mph fastball or stop a puck traveling even faster than that.

Main point: I fit these because they provide sharper, crisper vision than we can sometimes get with soft lenses on patients with astigmatism, and it is for this reason that I'm mentioning them on a Sports Vision blog. (They also make even more specialized lenses for other situations.)

You can find out more at their own website, www.synergeyes.com.

The next lens I'd like to mention has drawn some strange looks from people when I start to explain it. It's a lens that re-shapes the front surface of the eye while you sleep, and it's called Paragon CRT (Corneal Refractive Therapy.) I promise, I'm not making this up!

The idea of reshaping the front of the cornea with a contact lens is nothing new. Long before I went into practice, it was known that hard lenses caused changes to occur whether we wanted them to or not. So there was a search to make these changes happen in a controlled and predictable way, in hopes of eliminating the need for a correction altogether. This process is called orthokeratology, and a diehard "ortho-K doc" would probably give a much longer (and better) definition than I just did; but mine works fine here.

These are rigid, oxygen-permeable lenses with very high oxygen transmission. We actually use the term RGP for Rigid Gas Permeable, because we not only want oxygen to get through the lens, we also want carbon dioxide to come out from behind it - and these lenses allow both gases to pass right through.

They are fairly large as RGP's go, so they remain centered on the eye during sleep (yeah, you really do wear these things to bed.) The center of the lens is fitted a bit flatter than the front of the eye, so the effect is to flatten the cornea, as is done with a laser when performing LASIK on a nearsighted person - except without surgery! The more correction we need, the more we flatten the front of the cornea, up to the limits within which these things work.

Their effect is not permanent, so if you stop wearing them, the eyes will return to their original shape. And there is even some work going on to determine if they help prevent further changes in the eyes of kids whose eyes are rapidly becoming more nearsighted with each passing year.

Why mention them in a SV blog? OK, here we go: they provide an alternative to laser vision correction for athletes who are either too young for laser (under 19 or so) or just don't want to have laser correction. They permit clear vision while wearing no lenses at all, so there is no worry about lenses falling out (and we all know that even soft lenses can fall out now and then - just ask Jacoby Ellsbury, or see my post of 8/24/08. BTW, a few soft lens wearers have echoed my reaction to that incident: "They should've let him put them in himself from the start.")

They are also good for athletes who have tried regular soft lenses but whose eyes are just too dry, and those who have trouble wearing lenses due to allergies.

For more information, you can check their site at www.paragoncrt.com.

P.S. I have a new site for my regular optometric practice: www.prattvilleeye.com.