deducing a reading/computer rx from a general rx

Why do some opticians refuse to make
reading/computer glasses based on a
"zero to infinity" prescription? What is
the difficulty in going from

-1.25 +1.00 005 +2.50
plano +0.25 35 +2.50

to a reading/computer rx? The best
readers I ever bought were made without
a special rx in a small 20x20' lab.

Thanks, H.K.

 

Because you need someone to decide the proper "add", and that depends on
lots of factors.

w.stacy, o.d.

 

oops I didn't see the add, which is already there. There should be no
problem with filling this in a single vision near Rx.

w.stacy, o.d.

 

More than the object distance and the particular person's accomodative
ability, what?

 

Well, for starters, age, accommodative amplitude, convergence angles
(AC/A ratio), convergence reserves, range of near demand (from how
close in to how far out), depth of focus, length of arms, expected
ambient lighting levels, and the acuity needed for the expected tasks.
There are others, but you can start with those. Obviously you can do
the simple power/distance formula, and work it out yourself. You could
also try prescribing drugs for yourself these days, and buying your
questionable medications from highly doubtful sources on the internet,
how about an appendectomy. Caveat Emptor

w.stacy, o.d.

 

One nice thing about doing that is usually the remakes are free.
Nobody's perfect.

Wow. An o.m.d. who understands pupillary distances. I'm impressed.

w.stacy, o.d.

 

schreef:

There is no difficulty for a real optician.(like Martello in this newsgroup)

Maybe there is a problem in the USA, where opticians aren't supposed or
allowed to use their brains.

Living in The Netherlands, this is an unknown problem. (that's to say,
if you are dealing with a real optician)

Jan (normally Dutch spoken)

 

schreef:

There is no difficulty for a real optician.(like Robert Martellaro in
this newsgroup)

Maybe there is a problem in the USA, where opticians aren't supposed or
allowed to use their brains.

Living in The Netherlands, this is an unknown problem. (that's to say,
if you are dealing with a real optician)

Jan (normally Dutch spoken)

 

Jan's answer scores a direct hit. The optician
forwarded our request for reading/computer
glasses to the ophthalmologist via the doc's tech,
who placed our request on the doc's desk.
Two days later we returned to the optician who
had the old prescription revised by a +1.25 for
reading. I doubt it required an M.D. to divide
+2.50 by 2.

Close, but still no cigar: The optician could now
make me reading and distance glasses, but not
reading and computer -- because clearly only the
doctor knows how far away my computer screen
sits. How could the patient possibly know?

H.K.

 

I'm confused. The "add" of +2.50 should have been for reading. The
-1.25 and the +2.50 should have been added together, giving +1.25 for
the first eye, and the zero (plano) should have been added to the +2.50
giving +2.50 for the second eye. There's no division required, AFAIK,
which isn't much.

How the heck would the OMD know how far away your personal computer
screen was without measuring it? And they don't make house calls. The
doctor could guess or have you look at a computer in the office. Better
yet, measure it yourself.

 

schreef:

I should say you can.

Take a seat in front of your screen as you are used to and measure the
distance eye - screen, not difficult at all.

The addition of +1,25 dpt on top of the prescription for distance gives
a working distance of 100/1.25 = 80 cm. (no accommodation needed)

If you still have the possibility to accommodate 0.5 dpts on your own ,
you get a working distance range from 100/1.75 = 57cm to 100/1.25 = 80cm

If you have +0.25 dpt left to accommodate the range is 67cm to 80 cm

If you want a working distance of about 67 cm and having no
accommodating left you need an addition of +1.50 dpt.

The above is is only meant for your (Herbert) needs.
Your first addition of +2.50 for reading close (40 cm) says you have
little to non accommodation left.

As far as I know an optician in the USA is not allowed to make this
decision on his own.


Jan (normally Dutch spoken)

 

Jan, you and Dr. Abel missed the sarcasm in
my question, "How can the patient possibly know?"
Of course the patient knows; it's the doctor who
does not know the distance to the computer. So
why must the optician consult the doctor?

The upshot is that we didn't have time for a third
iteration with the doctor, filled the original prescription,
and now my wife is using non-prescription readers
from the drug store. I believe the story would have
concluded better in your country.

H.K.

 

That's newsgroups. People say the most outrageous things, so the
tendency is to take people literally, unless they follow their sarasm or
joke with a smiley symbol like this:

 

schreef:

I have thought about it, but being careful, I did go for an safe answer.

He could have asked for what purpose you wanted your prescription, a
quite normal question for an optometrist and quite normal to prescribe
according to these findings.

BTW, you mentioned you have visit an ophthalmologist instead of an
optometrist.
Seeing the "+" notation of the cylinder it could be true.

Although an ophthalmologist should be capable in prescribing for
glasses, it is my opinion an optometrist (in general) performs better in
this field of eyecare.

Then your wife's vision when working at the computer isn't what it
should be, namely comfortable.

For the computer only your wife's prescription should have shown this

S+1,00=C-1,00 95
S+1,50=C-0,25 125

For bifocal or progressives (multifocal) at the computer and reading
nearby it should be. (no distancepower)

S+1,00=C-1,00 95 add 1,25
S+1,50=C-0,25 125 add 1,25

BTW, in The Netherlands we have glasses just designed for such a purpose
and I'm almost certain they exist to in the USA.


Differences in spherical power and in cylinder power made your decision
to buy a drugstore spectacle a more or less bad choice.

THE reason why of the counter glasses are NOT preferred in general, they
simply are only meant for use in need, when you forgot your glasses.

Why?
Right and left the lenses of these kind of glasses have the same
spherical power and that's not what your wife is needing.

My advise?
Buy her a pair of glasses made properly, she love you (even more)for it.

Jan (normally Dutch spoken)

 

schreef:

I have thought about it, but being careful, I did go for an safe answer.

He could have asked for what purpose you wanted your prescription, a
quite normal question for an optometrist and quite normal to prescribe
according to these findings.

BTW, you mentioned you have visit an ophthalmologist instead of an
optometrist.
Seeing the "+" notation of the cylinder it could be true.

Although an ophthalmologist should be capable in prescribing for
glasses, it is my opinion an optometrist (in general) performs better in
this field of eyecare.

Then your wife's vision when working at the computer isn't what it
should be, namely comfortable.

For the computer only your wife's prescription should have shown this

S+1,00=C-1,00 95
S+1,50=C-0,25 125

For bifocal or progressives (multifocal) at the computer and reading
nearby it should be. (no distancepower)

S+1,00=C-1,00 95 add 1,25
S+1,50=C-0,25 125 add 1,25

BTW, in The Netherlands we have glasses just designed for such a purpose
and I'm almost certain they exist too in the USA.


Differences in spherical power and in cylinder power made your decision
to buy a drugstore spectacle a more or less bad choice.

THE reason why of the counter glasses are NOT preferred in general, they
simply are only meant for use in need, when you forgot your glasses.

Why?
Right and left the lenses of these kind of glasses have the same
spherical power and that's not what your wife is needing.

My advise?
Buy her a pair of glasses made properly, she love you (even more)for it.

Jan (normally Dutch spoken)

 

But, not a normal question for an optician, which, at least in the US, is
quite different from an optometrist.

 

Scott Seidman schreef:

It is clear I did respond on "the doctor" as seen above.

However, in The Netherlands it's quite normal to have glasses prescribed
by opticians , legally of course.

About 97% of the glasses are.

And our blindness percentage is still small, thanks to these opticians
who are sending every suspicious looking refraction to an optometrist or
an ophthalmologist.

I suppose real opticians in your country are clever enough to perform
the same.

Look at the history of America's optometrists, who lays the foundations
of the optometry profession you think, ophthalmologists or opticians?

Jan (normally Dutch spoken)

 

They may be clever enough, but they're certainly not trained enough.
Pharmacists are pretty smart too, but they don't write prescriptions.

I presume you guys also have an orthoptist or two hanging around. You
won't see those in the US very often, if at all.

 

Scott Seidman schreef:

You are right, the profession has forgotten there earlier skills.

Orthopsy and optometry are melting together nowadays in my country , the
real orthoptists left(almost only women) are working under supervision
of ophthalmologists in hospitals.

In general you can find optometrists working together with
ophthalmologists in the same office (hospitals) ore in optical shops.

Some optometrists have tried to make a living just as an optometrist
however in my country there is no way to earn your money properly doing so.

In the USA it is easier, opticians are not allowed to prescribe for glasses.

In general prescribing for glasses didn't concern ophthalmologists
either in the US. (also not in my country)

So work enough besides your job, in finding, or finding no pathology as
an American optometrist.

Jan (normally Dutch spoken)

 

In the UK I believe it's the difference between Ophthalmic Opticians
and Dispensing Opticians. The former do the eye testing and the
latter don't.

Ann