what lens is my optician on about?

[Carol Vines]

my optician has been trying for many months now to refit a rgp corneal lens for my right eye; have had 5 lenses so far but it still lifts at the bottom.

so he's just rang me and asked if i'm willing to try a different type of lens - still rgp but the lens comes in kit form with different lens in it; instead of ordering specific lenses to fit my eye. i've said yes but didn't fully understand what type of lens he's actually ordering anyone got any clues thanks

[jayuk]

Carol

Basically RGP's come in varied measurements (base curve, steepness, etc) and thus lens manufacturers provide what they call a "fitting set" to opticians.

As Keratoconus is never the same in every eye, its very difficult for optometrists to pre-order lenses. Therefore, what they do is provide a fitting set of anything from 6-24 lenses with varied measurements.

The optometrist can then take a look at the eye and perform tests and can then guesstimate which lens from the fitting set would be suitable.

They then refer to the fitting set and put a suitable lens in the eye (having applied fluorescein) and take a look under the slit-lamp and observe the fluorescein patterns...from there its the trial and error saga

hope that helps

J

[GarethB]

Hi Carol,

In addition, if one lens fits well in one area such as the bottom so it does not lift, but poor fit at the top, but the next lens has the opposite the optom can record this and request a lens half way between the two.

For me it was a case of four lenses fitting to a certain degree, non of which were ideal. Howvere getting elemnts of all served me well for 12 months.

Past 6 months have gone through same process, but decided on a larger corneal lens that will have the edges below the eye lids so if the lens lifts, I should be unable to blink it out easily.