Contact Lenses

Hi,

I have been wearing glasses for about ten years now, and have been told in
the past that I would not be a suitable candidate for contact lenses. Prior
to getting my glasses I was having headaches which was caused by
hypertropia/hypotropia (misalignment vertically) in each eye and prisms were
prescribed.

I am short sighted (sphere left -3.00, sphere right -4.00) and have
astigmatism (cylinder left -1.00, right -0.75, axis left 175, right 180).
Prism in the right eye is 1.50 down, left eye 1.5 up.

I have been searching on the internet and have found that you can only have
base down contact lenses for prescribed prisms. I have two questions, Would
I be able to get away with correction in only one (right) eye (1.5 down),
and would it be possible to bring the right eye down 3.0 to level with the
left (which would mean both are at 1.5 down)?


Thanks,
Tristan.

Yes you can, but if the weight and edge thickness pulls the lens down,
so that it rides lower than the other lens, the effective prism will be
less, so it will be a challenge to the fitter, to say the least.

w.stacy, o.d.

Tristan wrote:

> Hi,
>
> I have been wearing glasses for about ten years now, and have been told in
> the past that I would not be a suitable candidate for contact lenses. Prior
> to getting my glasses I was having headaches which was caused by
> hypertropia/hypotropia (misalignment vertically) in each eye and prisms were
> prescribed.
>
> I am short sighted (sphere left -3.00, sphere right -4.00) and have
> astigmatism (cylinder left -1.00, right -0.75, axis left 175, right 180).
> Prism in the right eye is 1.50 down, left eye 1.5 up.
>
> I have been searching on the internet and have found that you can only have
> base down contact lenses for prescribed prisms. I have two questions, Would
> I be able to get away with correction in only one (right) eye (1.5 down),
> and would it be possible to bring the right eye down 3.0 to level with the
> left (which would mean both are at 1.5 down)?
>
>
> Thanks,
> Tristan.
>
>

The reason that the prism has been split between the two eyes is to
minimize the effect that the prism has on the thickness of the lenses.
Three prism diopters base down in the O.D. has the same effect as 1.5
down in the O.D. combined with 1.5 up in the O.S.

DrG

Hi Tristan,

I have fitted contact lenses with your sort of prescription. It is not
always successful. If the base down prism is fitted on the deviating eye
then there seems to more chance of success.

I have found that the manufactures I use will only do the correction in
soft materials and low to mid-water content.Use of these materials as well
as being bespoke should mask the astigmatism.

Regards


Ian Hodgson - Isle of Man
"Tristan" <(E-Mail Removed)> wrote in message
news:GTH4f.20052$(E-Mail Removed)...
> Hi,
>
> I have been wearing glasses for about ten years now, and have been told in
> the past that I would not be a suitable candidate for contact lenses.
Prior
> to getting my glasses I was having headaches which was caused by
> hypertropia/hypotropia (misalignment vertically) in each eye and prisms
were
> prescribed.
>
> I am short sighted (sphere left -3.00, sphere right -4.00) and have
> astigmatism (cylinder left -1.00, right -0.75, axis left 175, right 180).
> Prism in the right eye is 1.50 down, left eye 1.5 up.
>
> I have been searching on the internet and have found that you can only
have
> base down contact lenses for prescribed prisms. I have two questions,
Would
> I be able to get away with correction in only one (right) eye (1.5 down),
> and would it be possible to bring the right eye down 3.0 to level with the
> left (which would mean both are at 1.5 down)?
>
>
> Thanks,
> Tristan.
>
>

"Tristan" <(E-Mail Removed)> schreef in bericht
news:GTH4f.20052$(E-Mail Removed)...
> Hi,
>
> I have been wearing glasses for about ten years now, and have been told in
> the past that I would not be a suitable candidate for contact lenses.
> Prior
> to getting my glasses I was having headaches which was caused by
> hypertropia/hypotropia (misalignment vertically) in each eye and prisms
> were
> prescribed.
>
> I am short sighted (sphere left -3.00, sphere right -4.00) and have
> astigmatism (cylinder left -1.00, right -0.75, axis left 175, right 180).
> Prism in the right eye is 1.50 down, left eye 1.5 up.
>
> I have been searching on the internet and have found that you can only
> have
> base down contact lenses for prescribed prisms. I have two questions,
> Would
> I be able to get away with correction in only one (right) eye (1.5 down),
> and would it be possible to bring the right eye down 3.0 to level with the
> left (which would mean both are at 1.5 down)?

Tristan, contactlenses (RGP) are possible with an effective prismatic power
off about 2 prism.
Ask your eyecareproffessional if this is enough to avoid your headaches if a
RGP contactlens is placed on the right eye (the base of the prism
automaticly falling down).
In this way, you are 1 prism short in your correction
As you said, a prism of a power 3 is needed but such contactlenses are
impossible to wear so ask your practioner what he/she thinks.

TMHO soft contactlenses are not a possibility.

--
Jan (normally Dutch spoken)