vision after lens removal

If a person were very nearsighted and then had his natural lens
removed, what sort of vision might he have? Could his eye structure
and cornea provide near "normal" distance correction? If not, why not?

Dear cda,

Subject: The power of the lens of the eye.

The power of the eye's lens is about 10 diopters.

If that is removed, the total refractive power of the eye
is changed by that amount.

If the person had a refractive STATE of -5 diopters before
the removal of the lens (say for caterack), then the
eye's power would change to +5 diopters (by
simple optics.

The IOL is normally determined by calculation so
that when the lens is replaced, the eye's refractive
STATE is made approximately zero.

It is a great idea and it WORKS!

Best,

Otis


On Apr 1, 12:37 pm, cda...@directflatscreen.tv wrote:
> If a person were very nearsighted and then had his natural lens
> removed, what sort of vision might he have? Could his eye structure
> and cornea provide near "normal" distance correction? If not, why not?

On Apr 1, 11:17 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Dear cda,
>
> Subject: The power of the lens of the eye.
>
> The power of the eye's lens is about 10 diopters.
>
> If that is removed, the total refractive power of the eye
> is changed by that amount.
>
> If the person had a refractive STATE of -5 diopters before
> the removal of the lens (say for caterack), then the
> eye's power would change to +5 diopters (by
> simple optics.
>
> The IOL is normally determined by calculation so
> that when the lens is replaced, the eye's refractive
> STATE is made approximately zero.
>
> It is a great idea and it WORKS!
>
> Best,
>
> Otis
>
> On Apr 1, 12:37 pm, cda...@directflatscreen.tv wrote:
>
> > If a person were very nearsighted and then had his natural lens
> > removed, what sort of vision might he have? Could his eye structure
> > and cornea provide near "normal" distance correction? If not, why not?

So if I were +1.5 then I would be +11.5 and if I were -13.5 then I
would be -3.5 without any lens or IOL?

On Apr 1, 2:54 pm, "Dr Judy" <mpac...@rogers.com> wrote:
> On Apr 1, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
> > Dear cda,
>
> > Subject: The power of the lens of the eye.
>
> > The power of the eye's lens is about 10 diopters.
>
> Actually it is about 14D to 20D. The model of the average eye has a
> total refractive power of about 60D, with 43D from the cornea and 17D
> from the lens.
>
> Before intraocular lenses were in use, patients typically had +12 to
> +20 refraction after cataract surgery. A high myope (> -14D) may be
> close to no refractive error after cataract surgery.
>
> Dr Judy

If there were no cataracts and a person was +1.5 before surgery then
an IOL of +20.5 might not be out of line? What if a person was -13.5
and an IOL of +13.5 were put in?

Dear Cda,

This is a matter of calculation before the surgery.

Knowing the refractive state of the eye before the
surgery, and by use of ultra-sound, the replacement
IOL is calculated.

The result, if done correctly is a total refractive state
of approximately zero -- which is the goal.

Since the IOL can not "accommodate", it follows that
the person can have the IOL tailored for "near" or "far",
or an intermediate position.

For instance the "target" could be a refractive STATE of
-1.0 diopters which would allow near vision (with depth-of-focus
of 1 to 2 diopters), and far vision of about 20/60.

Thus a mild minus of about -1 diopter could be used
to pass the DMV, but for most purposes the person
could function with no lens at all.

The person would need a mild plus for restaurants
with low level illumination.

Further, the person could request "mono-vision" where
a DIFFERENCE in refractive state was intentional.

Thus one eye could be close to 20/20, and
the other eye at -1 diopters.

Best,

Otis



On Apr 1, 7:32 pm, cda...@directflatscreen.tv wrote:
> On Apr 1, 2:54 pm, "Dr Judy" <mpac...@rogers.com> wrote:
>
>
>
>
>
> > On Apr 1, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
> > > Dear cda,
>
> > > Subject: The power of the lens of the eye.
>
> > > The power of the eye's lens is about 10 diopters.
>
> > Actually it is about 14D to 20D. The model of the average eye has a
> > total refractive power of about 60D, with 43D from the cornea and 17D
> > from the lens.
>
> > Before intraocular lenses were in use, patients typically had +12 to
> > +20 refraction after cataract surgery. A high myope (> -14D) may be
> > close to no refractive error after cataract surgery.
>
> > Dr Judy
>
> If there were no cataracts and a person was +1.5 before surgery then
> an IOL of +20.5 might not be out of line? What if a person was -13.5
> and an IOL of +13.5 were put in?- Hide quoted text -
>
> - Show quoted text -

On Apr 1, 10:00 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Dear Cda,
>
> This is a matter of calculation before the surgery.
>
> Knowing the refractive state of the eye before the
> surgery, and by use of ultra-sound, the replacement
> IOL is calculated.
>
> The result, if done correctly is a total refractive state
> of approximately zero -- which is the goal.
>
> Since the IOL can not "accommodate", it follows that
> the person can have the IOL tailored for "near" or "far",
> or an intermediate position.
>
> For instance the "target" could be a refractive STATE of
> -1.0 diopters which would allow near vision (with depth-of-focus
> of 1 to 2 diopters), and far vision of about 20/60.
>
> Thus a mild minus of about -1 diopter could be used
> to pass the DMV, but for most purposes the person
> could function with no lens at all.
>
> The person would need a mild plus for restaurants
> with low level illumination.
>
> Further, the person could request "mono-vision" where
> a DIFFERENCE in refractive state was intentional.
>
> Thus one eye could be close to 20/20, and
> the other eye at -1 diopters.
>
> Best,
>
> Otis
>
> On Apr 1, 7:32 pm, cda...@directflatscreen.tv wrote:
>
> > On Apr 1, 2:54 pm, "Dr Judy" <mpac...@rogers.com> wrote:
>
> > > On Apr 1, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
> > > > Dear cda,
>
> > > > Subject: The power of the lens of the eye.
>
> > > > The power of the eye's lens is about 10 diopters.
>
> > > Actually it is about 14D to 20D. The model of the average eye has a
> > > total refractive power of about 60D, with 43D from the cornea and 17D
> > > from the lens.
>
> > > Before intraocular lenses were in use, patients typically had +12 to
> > > +20 refraction after cataract surgery. A high myope (> -14D) may be
> > > close to no refractive error after cataract surgery.
>
> > > Dr Judy
>
> > If there were no cataracts and a person was +1.5 before surgery then
> > an IOL of +20.5 might not be out of line? What if a person was -13.5
> > and an IOL of +13.5 were put in?- Hide quoted text -
>
> > - Show quoted text -

please disregard the poster named otis brown. as he has demonstrated,
his facts are inaccurate. he is nothing more than an amateur with a
fetish for issues relating to the human eye, combined with a desire to
see his posts appear on the internet. the value of his posts is less
than zero.

Dear PClar,

Please explain to CDA EXACTLY what statement I made
that was not accurate -- in YOUR judgment.

I am certain he would like to hear YOUR opinion.

All you wish to do is to denounce people -- never
help them at all.

Now, please explain, and an optometrist, how
you understand the use of a replacement lens.

Otis



On Apr 1, 10:18 pm, p.clar...@gmail.com wrote:
> On Apr 1, 10:00 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
>
>
>
>
> > Dear Cda,
>
> > This is a matter of calculation before the surgery.
>
> > Knowing the refractive state of the eye before the
> > surgery, and by use of ultra-sound, the replacement
> > IOL is calculated.
>
> > The result, if done correctly is a total refractive state
> > of approximately zero -- which is the goal.
>
> > Since the IOL can not "accommodate", it follows that
> > the person can have the IOL tailored for "near" or "far",
> > or an intermediate position.
>
> > For instance the "target" could be a refractive STATE of
> > -1.0 diopters which would allow near vision (with depth-of-focus
> > of 1 to 2 diopters), and far vision of about 20/60.
>
> > Thus a mild minus of about -1 diopter could be used
> > to pass the DMV, but for most purposes the person
> > could function with no lens at all.
>
> > The person would need a mild plus for restaurants
> > with low level illumination.
>
> > Further, the person could request "mono-vision" where
> > a DIFFERENCE in refractive state was intentional.
>
> > Thus one eye could be close to 20/20, and
> > the other eye at -1 diopters.
>
> > Best,
>
> > Otis
>
> > On Apr 1, 7:32 pm, cda...@directflatscreen.tv wrote:
>
> > > On Apr 1, 2:54 pm, "Dr Judy" <mpac...@rogers.com> wrote:
>
> > > > On Apr 1, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
> > > > > Dear cda,
>
> > > > > Subject: The power of the lens of the eye.
>
> > > > > The power of the eye's lens is about 10 diopters.
>
> > > > Actually it is about 14D to 20D. The model of the average eye has a
> > > > total refractive power of about 60D, with 43D from the cornea and 17D
> > > > from the lens.
>
> > > > Before intraocular lenses were in use, patients typically had +12 to
> > > > +20 refraction after cataract surgery. A high myope (> -14D) may be
> > > > close to no refractive error after cataract surgery.
>
> > > > Dr Judy
>
> > > If there were no cataracts and a person was +1.5 before surgery then
> > > an IOL of +20.5 might not be out of line? What if a person was -13.5
> > > and an IOL of +13.5 were put in?- Hide quoted text -
>
> > > - Show quoted text -
>
> please disregard the poster named otis brown. as he has demonstrated,
> his facts are inaccurate. he is nothing more than an amateur with a
> fetish for issues relating to the human eye, combined with a desire to
> see his posts appear on the internet. the value of his posts is less
> than zero.- Hide quoted text -
>
> - Show quoted text -

On Apr 1, 7:18 pm, p.clar...@gmail.com wrote:
> On Apr 1, 10:00 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
>
>
> > Dear Cda,
>
> > This is a matter of calculation before the surgery.
>
> > Knowing the refractive state of the eye before the
> > surgery, and by use of ultra-sound, the replacement
> > IOL is calculated.
>
> > The result, if done correctly is a total refractive state
> > of approximately zero -- which is the goal.
>
> > Since the IOL can not "accommodate", it follows that
> > the person can have the IOL tailored for "near" or "far",
> > or an intermediate position.
>
> > For instance the "target" could be a refractive STATE of
> > -1.0 diopters which would allow near vision (with depth-of-focus
> > of 1 to 2 diopters), and far vision of about 20/60.
>
> > Thus a mild minus of about -1 diopter could be used
> > to pass the DMV, but for most purposes the person
> > could function with no lens at all.
>
> > The person would need a mild plus for restaurants
> > with low level illumination.
>
> > Further, the person could request "mono-vision" where
> > a DIFFERENCE in refractive state was intentional.
>
> > Thus one eye could be close to 20/20, and
> > the other eye at -1 diopters.
>
> > Best,
>
> > Otis
>
> > On Apr 1, 7:32 pm, cda...@directflatscreen.tv wrote:
>
> > > On Apr 1, 2:54 pm, "Dr Judy" <mpac...@rogers.com> wrote:
>
> > > > On Apr 1, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
> > > > > Dear cda,
>
> > > > > Subject: The power of the lens of the eye.
>
> > > > > The power of the eye's lens is about 10 diopters.
>
> > > > Actually it is about 14D to 20D. The model of the average eye has a
> > > > total refractive power of about 60D, with 43D from the cornea and 17D
> > > > from the lens.
>
> > > > Before intraocular lenses were in use, patients typically had +12 to
> > > > +20 refraction after cataract surgery. A high myope (> -14D) may be
> > > > close to no refractive error after cataract surgery.
>
> > > > Dr Judy
>
> > > If there were no cataracts and a person was +1.5 before surgery then
> > > an IOL of +20.5 might not be out of line? What if a person was -13.5
> > > and an IOL of +13.5 were put in?- Hide quoted text -
>
> > > - Show quoted text -
>
> please disregard the poster named otis brown. as he has demonstrated,
> his facts are inaccurate. he is nothing more than an amateur with a
> fetish for issues relating to the human eye, combined with a desire to
> see his posts appear on the internet. the value of his posts is less
> than zero.

His post here certainly gives a comprehensive overview of the
situation. I think I might choose to bring myopia in one eye closer
to the almost "normal" of the other eye. If a person is used to
wearing glasses anyway and expects to need correction after surgery
maybe distance vision in both eyes would be nice. The question in this
case is the proper determination of IOL power in the absence of
cataract. What other factors are used besides corneal curvature, axial
length, and present correction needed for distance?
Say a person had a prescription of:
OD -13.3
OS +0.50 -2.25 x170

Has K's of:
OD 44.37 x0 44.37 x0 7.61mm 7.61mm axial length: 25.48
OS 43.25 x175 45.50 x85 7.80mm 7.42mm axial length: 23.57

Also, what changes might be made to the calculation if a +1 grade
cataract were found before the natural lens was removed?

On Apr 1, 10:31 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Dear PClar,
>
> Please explain to CDA EXACTLY what statement I made
> that was not accurate -- in YOUR judgment.
>
> I am certain he would like to hear YOUR opinion.
>
> All you wish to do is to denounce people -- never
> help them at all.
>
> Now, please explain, and an optometrist, how
> you understand the use of a replacement lens.
>
> Otis

that you believe the refractive state of the cornea is about 10
diopters is ridiculuous. that you believe that a child with
intermittent eso needs to see an "behavioural optometrist" is
ridiculuous.

i have earned two advanced degrees-- vision research and optometry. i
currently practice optometry in the midwest US. i have participated
as an in-room observer in multiples types of ocular surgeries included
cataract, lasik, strabismus, etc.

my postings are helpful to many people here-- just not to you! you
are a foolish old man who gets involved in things he knows nothing
about and apparently isn't embarrassed by being made a fool of.

and how has the investigation by the State of Pennsylvania into the
claims that you are practicing medicine without a license coming
along? apparently they are slowing you down any?

go play shuffle-board and stick your nose out of everyone's business

and how has the investigation by the State of Pennsylvania into the
claims that you are practicing medicine without a license coming
along?

It turns out that the man was posting under a false name,
and making fradulent statements.

I contacted the agency, and forwared his posts. I stated
that I argued that a person should be supplied with
an HONEST choice by a second-opinion expert
optometrist like Steve Leung at:

www.chinamyopia.org

I stated that this preventive alternative must START before
the minus lens is applied.

I stated that I was an engineer, and suggested that they
read my site:

www.myopiafree.com

I provided references to the primate studies that
proved that the natural eye's refractive STATE follows
an applied -3 diopter lens -- always.

I stated that when experts disagree, then it is
wise for the person himself to be informed in a
manner that allows for intelligent choice.

I stated that once the minus lens is started, the
refractive STATE of the eye will go down
at a rate of -1/2 diopter per year.

I stated that my perspective is to provide
second-opinion information, and to
help the person find a SUPPORTIVE plus-prevention
optometrist.

The address supplied by the person who filed the
"charge" does not exist.

Otis


On Apr 2, 7:04 am, p.clar...@gmail.com wrote:
> On Apr 1, 10:31 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
>
> > Dear PClar,
>
> > Please explain to CDA EXACTLY what statement I made
> > that was not accurate -- in YOUR judgment.
>
> > I am certain he would like to hear YOUR opinion.
>
> > All you wish to do is to denounce people -- never
> > help them at all.
>
> > Now, please explain, and an optometrist, how
> > you understand the use of a replacement lens.
>
> > Otis
>
> that you believe the refractive state of the cornea is about 10
> diopters is ridiculuous. that you believe that a child with
> intermittent eso needs to see an "behavioural optometrist" is
> ridiculuous.
>
> i have earned two advanced degrees-- vision research and optometry. i
> currently practice optometry in the midwest US. i have participated
> as an in-room observer in multiples types of ocular surgeries included
> cataract, lasik, strabismus, etc.
>
> my postings are helpful to many people here-- just not to you! you
> are a foolish old man who gets involved in things he knows nothing
> about and apparently isn't embarrassed by being made a fool of.
>
> and how has the investigation by the State of Pennsylvania into the
> claims that you are practicing medicine without a license coming
> along? apparently they are slowing you down any?
>
> go play shuffle-board and stick your nose out of everyone's business