Medical Forum / General / Vision / April 2007
vision after lens removal
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cdavis@directflatscreen.tv - 01 Apr 2007 17:37 GMT 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?
otisbrown@pa.net - 01 Apr 2007 19:17 GMT 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? cdavis@directflatscreen.tv - 01 Apr 2007 22:04 GMT On Apr 1, 11:17 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Dear cda, > [quoted text clipped - 25 lines] > > 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?
Dr Judy - 01 Apr 2007 22:54 GMT 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
cdavis@directflatscreen.tv - 02 Apr 2007 00:32 GMT > On Apr 1, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote: > [quoted text clipped - 13 lines] > > 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?
Dr Judy - 02 Apr 2007 02:54 GMT On Apr 1, 7:32 pm, cda...@directflatscreen.tv wrote:
> > On Apr 1, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote: > [quoted text clipped - 16 lines] > 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? IOLs of that power are used.
What if a person was -13.5
> and an IOL of +13.5 were put in? Assuming the natural lens was +16 and ignoring some other placement factors, then the refraction after surgery would be -13.5 - (+16 - +13.5) = -11.00.
The real answer depends on eye length and corneal curvature. There is a formula that uses those numbers and some other eye measurements to calculate what refraction will result from what power of IOL .
Dr Judy
otisbrown@pa.net - 02 Apr 2007 03:00 GMT 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, 2:17 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote: > [quoted text clipped - 19 lines] > > - Show quoted text - p.clarkii@gmail.com - 02 Apr 2007 03:18 GMT On Apr 1, 10:00 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Dear Cda, > [quoted text clipped - 57 lines] > > > - 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.
otisbrown@pa.net - 02 Apr 2007 03:31 GMT 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: > [quoted text clipped - 67 lines] > > - Show quoted text - p.clarkii@gmail.com - 02 Apr 2007 12:04 GMT On Apr 1, 10:31 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Dear PClar, > [quoted text clipped - 10 lines] > > 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
otisbrown@pa.net - 02 Apr 2007 13:58 GMT 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: > [quoted text clipped - 32 lines] > > go play shuffle-board and stick your nose out of everyone's business p.clarkii@gmail.com - 02 Apr 2007 15:10 GMT On Apr 2, 8:58 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> and how has the investigation by the State of Pennsylvania into the > claims that you are practicing medicine without a license coming [quoted text clipped - 78 lines] > > > go play shuffle-board and stick your nose out of everyone's business you try to dupe people with lies and misinformation. perhaps Pennsylvania will take action against you like Iowa did against the foolish "I See Clearly" people. probably you are a little safer since you don't overtly try to sell any products-- except maybe your dumb book.
otisbrown@pa.net - 02 Apr 2007 15:25 GMT PClar,
You tell the public scientific lies when you state that the fundamental eye is not dynamic -- with respect to an applied -3 diopter lens. See:
http://www.geocities.com/otisbrown17268/FundEye.html
I would suggest that a person be informed of this fact, and encouraged to review the preventive alternative (that is preventing the developement of a negative refractive STATE) before that FIRST strong minus lens is applied, and the individual told to "...wear it all the time ... it is GOOD for you.".
I think you should respect the intelligence of the person, and show him the facts, rather than telling him convient office fibs.
And if the person "loves" the minus, that that would end your responsibility to him.
But at least he would respect you for being HONEST with him, and respecting his right of choice.
I know I would certainly respected the medical people I have talked to -- if they had taken that simple and honest step.
Is there any (none-medical) person posting on here who would OBJECT to being supplied with an honest second opinion?
And if so, why?
Otis
On Apr 2, 10:10 am, p.clar...@gmail.com wrote:
> On Apr 2, 8:58 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote: > [quoted text clipped - 88 lines] > > - Show quoted text - otisbrown@pa.net - 02 Apr 2007 15:32 GMT And PClar, I PERSONALLY wish I had been supported by] these preventive methods. And my book is supplied so that when you state, "there is an alternative to the quick-fix minus. If you want additional information, read:"
http://www.i-see.org/otis_brown/
And if you wish plus-prevention, then I will help you with it, or,
I, Pclar, can not, and will not support you with plus-prevention, but others WILL support you. Please go to an optometrist like Steve Leung, who has his own children wearing a plus for all close work so they AVOID ENTRY into a negative refractive STATE. See:
www.chinamyopia.org
I realize you must practice what you want to believe. But that is not what other optometrists believe -- because of the science concerning the proven dynamic behavior of the natural eye.
Otris
On Apr 2, 10:25 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> PClar, > [quoted text clipped - 129 lines] > > - Show quoted text - otisbrown@pa.net - 02 Apr 2007 15:37 GMT And to further enhance your understanding of this PREVENTIVE second-opinion I suggest you read this eBook on the subject.:
http://www.preventmyopia.org/ebook/
Otis
On Apr 2, 10:32 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> And PClar, I PERSONALLY wish I had been supported by] > these preventive methods. And my book is supplied so that [quoted text clipped - 157 lines] > > - Show quoted text - p.clarkii@gmail.com - 02 Apr 2007 17:10 GMT On Apr 2, 10:32 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> I realize you must practice what you want to believe. But > that is not what other optometrists believe -- because > of the science concerning the proven dynamic behavior > of the natural eye. > > Otris hello Otris, i guess the thorazine is beginning to kick in. anyway, why don't you give us the names of all the other optometrists who believe in your "second opinion" hogwash. we should have their state licensing boards consider revolking their licenses. or are there really any?
Neil Brooks - 02 Apr 2007 16:45 GMT On Apr 2, 7:25 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Is there any (none-medical) person posting on here who would OBJECT > to being supplied with an honest second opinion? > > And if so, why? This is simple ... because I believe you're pathologically ill.
You, yourself--on Alex's I-SEE board--stated that this whole -3.00d thing is an intentional over-correction to see what effect it MIGHT have WHEN TAKEN TO AN EXTREME.
As I said, 100 aspirin might kill a person.
What you're saying is that nobody should take a single aspirin because aspirin are inherently dangerous.
:Remember my line, Uncle Otie? "Safe when used as directed." This--among several thousand other things--makes you a fool.
p.clarkii@gmail.com - 02 Apr 2007 17:05 GMT On Apr 2, 10:25 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> PClar, > > You tell the public scientific lies when you state > that the fundamental eye is not dynamic -- with > respect to an applied -3 diopter lens. See: Err-- i don't recall ever saying this. why are you putting words in my mouth?
the "-3.00 diopter" data that you are referring to is performed on monkeys, not humans. Goss et al. presented data in humans showing that overminusing by -0.75D had no effect on myopia progression in children. why do you ignor human data and grasp onto extrapolation from old experiments done on lenses sutured onto the eyes of monkeys? you are not capable of objective thinking.
> http://www.geocities.com/otisbrown17268/FundEye.html > > I would suggest that a person be informed of this fact, this site has nothing to do with facts. it is the thought process of a kook. unless of course we are worried about inducing myopia in monkeys where the article you salute clearly supports that we should not overminus them by -3.00 or they might become myopic (not to mention develop a crashing headache and have their eyes cross).
> and encouraged to review the preventive > alternative (that is preventing the developement [quoted text clipped - 6 lines] > and show him the facts, rather than telling him > convient office fibs. i have scientific references which document my claims. the facts are that: 1. minus lenses do not induce myopia 2. plus lenses or bifocals do not prevent myopia
please present us YOUR data, performed on human subjects (these issues HAVE been studies in humans) which supports your claims. and quit telling your internet fibs (aka LIES).
> And if the person "loves" the minus, that that would > end your responsibility to him. [quoted text clipped - 12 lines] > > Otis Otis, the number of people in the entire world who believe in your totally unsupported theory ("second opinion") can be counted with the fingers on 1 hand. it all has been disproven in the last 25 years. why won't you get on PubMed and Google Scholar and do a little searching.
People aren't interested in your so-called "second opinion" because its rubbish. such people might as well get their information from the National Enquirer.
you are a pathetic, and frankly sick, man
William Stacy - 02 Apr 2007 18:01 GMT You too? In the days when I was responding to Otris' stuff, he would say repeatedly that I said that the eye is not "dynamic", which was a complete fabrication as everyone knows the young healthy human eye is very dynamic. It's just that his definition of dynamic is not the English definition. Just like his definitions of natural, fundamental, refractive state, minus and plus to name a few are not from around here...
w.stacy, o.d.
>On Apr 2, 10:25 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote: > [quoted text clipped - 88 lines] > > cdavis@directflatscreen.tv - 02 Apr 2007 19:09 GMT > You too? In the days when I was responding to Otris' stuff, he would > say repeatedly that I said that the eye is not "dynamic", which was a [quoted text clipped - 83 lines] > > >you are a pathetic, and frankly sick, man Is anyone in this group professional? Or does everyone forget they've been on this merry-go-round before? Life is just a bit of history repeated until the clearing at the end of the path is attained.
Neil Brooks - 02 Apr 2007 19:24 GMT On Apr 2, 11:09 am, cda...@directflatscreen.tv wrote:
> Is anyone in this group professional? Or does everyone forget they've > been on this merry-go-round before? Life is just a bit of history > repeated until the clearing at the end of the path is attained. I'd say you're new here, huh?
I'm not.
Absent Otis, everybody here is kind, helpful, and professional. Otis is poisonous to an otherwise exceptional group.
Look back at about 7+ years of history before rendering judgment on those who respond to him.
cdavis@directflatscreen.tv - 03 Apr 2007 17:55 GMT > On Apr 2, 11:09 am, cda...@directflatscreen.tv wrote: > [quoted text clipped - 11 lines] > Look back at about 7+ years of history before rendering judgment on > those who respond to him. I'm not rendering judgement. I'm just curious as to why anyone would continue to carry on such a "conversation" when there is no resolution in sight. No pun intended. If it brightens up your day, go for it. Unless Otis's opinions have caused harm to someone there is no need to be confrontational. Use your expertise to answer real questions from real people. Best regards, CDavis
Neil Brooks - 04 Apr 2007 02:00 GMT On Apr 3, 9:55 am, cda...@directflatscreen.tv wrote:
> Unless Otis's opinions have caused harm to someone there is no need to > be confrontational. They have.
I reported just shy of a dozen cases of double vision--induced in unsuspecting people following Otis's advice, whether for themselves or their children--to the State of Pennsylvania who has an open investigation on the matter.
The fact that Otis "prescribes" to pre-teen children, and without parental consent, is repugnant to most people.
otisbrown@pa.net - 04 Apr 2007 02:28 GMT > On Apr 3, 9:55 am, cda...@directflatscreen.tv wrote: > [quoted text clipped - 10 lines] > The fact that Otis "prescribes" to pre-teen children, and without > parental consent, is repugnant to most people. otisbrown@pa.net - 04 Apr 2007 02:37 GMT Dear CDA,
Subject: Neil Brooks "qualfications".
Neil Brooks has no medical qualifications to make any medical statement.
He makes mindless statements with no scientific support.
The minus lens indeed profoudly "easy", and works instantly -- but that is hardly a scientific justification.
Perhaps you should as Neil to provide his qualifications to make the statements he is making.
Medicine and science are both developing concepts.
I have identified myself as an engineer, by training, and have reviewed the subject understand the wisdom of the preventive second-opinion.
I have stated many times that I would send you to an optometrist who has his own children wearing a plus (for prevention) to AVOID entry into a negative refractive STATE.
It is true that plus-prevention required personal resolve, and a decision or choice for the parents.
But even in ophthamology, some medical doctors believe it is wise as Dr. Romano states.
Foreword
Ophthalmologists, optometrists and research workers are responsible for the second opinion presented in this book, that nearsightedness (myopia) is as much, if not greatly more, due to environment (and avoidable) than heredity (unavoidable).
The essence of avoiding myopia is using a plus lens (a mild magnifying glass, as in reading glasses required by older people) before the eye becomes seriously nearsighted.
If the approach advocated in this book is to work properly, you must take full responsibility to develop a clear understanding of the normal eye's behavior. In addition, you must personally implement the practical method of prevention. In this situation we can only offer the student of science an accurate picture of existing practices, as well as an education about the fundamental behavioral characteristic of the normal eye. This approach will put you in full control of your visual welfare.
The author has demonstrated a depth of understanding of the problems and limits that occur in existing health practice. With good judgment, and personal effort, it is highly probable that you can avoid nearsightedness.
Paul E. Romano M.D., M.S.O. Professor of Ophthalmology, University of Florida, Gainesville
+++++++++++++++++++++
It is always a good idea to evaluate the scientific fact concerning the dynamic behavior of the fundamental eye -- and consider the preventive alternative, before stair-case myopia develops.
Then I do agree that vision-clearing does become impossible.
In other words, a stich in time saves nine.
Otis
Neil Brooks - 04 Apr 2007 03:36 GMT On Apr 3, 6:37 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Subject: Neil Brooks "qualfications". Still irrelevant ... after all these years.
> He makes mindless statements with no scientific support. Actually, I ask pointed, logical, coherent, and relevant questions ... that you don't answer.
See: http://nbeener.com/NDB_OSB_Qs.txt
p.clarkii@gmail.com - 04 Apr 2007 08:37 GMT On Apr 3, 9:37 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> Dear CDA, > > Subject: Neil Brooks "qualfications". this is not the subject. the subject is YOUR qualifications.
> Neil Brooks has no medical qualifications to make any > medical statement. > > He makes mindless statements with no scientific support. the above two statements relate to YOU.
> I have identified myself as an engineer, by training, and > have reviewed the subject understand the wisdom > of the preventive second-opinion. what about the "wisdom" of paying any regard to the studies that have tested myopia prevention with plus lenses, removing glasses, undercorrection, etc. how come all the HUMAN studies show that the "wretched minus" really isn't so evil after all. how come the simple minded notion that relaxing accommodation by using plus readers simply doesn't in reality have any effect on preventing myopia-- at least in the REAL world-- maybe not in the fantasy world that is in the mind of Otris who decides what is right and wrong and who believes he is smarter than science!
> But even in ophthamology, some medical doctors > believe it is wise as Dr. Romano states. tell me, are you "good friends" with dr romano just as you are with ted grosvenor (who never heard of you before)? ;)
are you friends in real life or in your fantasy world where your beliefs are held in high esteem and where you are regarded as a savior to the vision of the poor victims of evil optometrists who conspire to hook people on the wretched minus.
Neil Brooks - 02 Apr 2007 16:41 GMT On Apr 2, 5:58 am, "otisbr...@pa.net" <otisbr...@pa.net> wrote:
> 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. Liar.
The process was initiated using my TRUE name and making perfectly honest, accurate, and valid statements ... that the State of Pennsylvania then investigated. They are awaiting additional complainants willing to attest.
I'm sure you'll provide a few in due course.
> The address supplied by the person who filed the > "charge" does not exist. Liar. I gave--and YOU POSTED--my real, valid address.
You should stop lying. It's indicative of poor moral character.
cdavis@directflatscreen.tv - 02 Apr 2007 04:11 GMT On Apr 1, 7:18 pm, p.clar...@gmail.com wrote:
> On Apr 1, 10:00 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote: > [quoted text clipped - 65 lines] > 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?
Dr Judy - 02 Apr 2007 19:18 GMT On Apr 1, 11:11 pm, cda...@directflatscreen.tv wrote:
>The question in this > case is the proper determination of IOL power in the absence of [quoted text clipped - 7 lines] > 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 The current prescription is not a factor. There are a number of other eye measures obtained with ultrasound including anterior chamber depth, position of the lens capsule that factor into the formula. More than one formular exists and surgeons chose a formula based on their experience, the type of ultrasound used and some eye factors.
Whether or not a cataract currently exists doesn't matter as the lens will be removed.
Here is a link to formula discussion:
http://www.crstodayarchive.com/03_archive/0202/crst0202_1_041.html
Dr Judy
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