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Medical Forum / General / Vision / October 2007How Much Can My Eyes Changes?
I've been wearing glasses for about 4 1/2 years now. My first prescription, Jan '03, was SPH CYL AXIS ADD -.87 +.25 90 +1.25 -.87 +.25 90 +1.25 Then in Feb '04 it was SPH CYL AXIS ADD -.75 - - +1.75 -1.00 - - +1.75 Now, Aug '07, it is: SPH CYL AXIS ADD -.75 - - +2.25 -.75 - - +2.25 I got progressive lenses based on my August '07 prescription in early September. Furthermore I've noticed a couple of interesting phenomena. 1. I have a digital alarm clock on my dresser about 10 feet from where I sleep. The numerals are about 3/4 of an inch high. When I look at the clock a few minutes after retiring, with the lights off, the numbers are not in focus. However when I wake up in the morning I can read the clock perfectly. Crystal clear. 2. When I go grocery shopping I have noticed that sometimes I can read far away category signs hanging above the aisles with ease and sometimes they aren't in focus. I've compared this on several differing occasions from the same spot in the store on the same far away sign with varying results. 3. I've noticed that highway signs viewed from a certain distance that used to be clear when I first got my new glasses are now not as clear. I've taken my glasses to three different optometrist's shops and had them check my glasses on a lensometer. They all come back with -.75 on the OD measurements and (2 out of 3) with +2.25 on the add portion. So what's going on? Have my eyes changed in 2 months? Do they change from day-to-day? Overnight? How do you explain no cyl. or axis components in my last 2 prescriptions? So what's going on? Have my eyes changed in 2 months? Do they change from day-to-day? Overnight? Otis> None of the measurements are "perfectly accurate". Depending on measurement conditions, you could see variations of 1/4 to 1/2 diopter -- depending on the OD making the measurements. How do you explain no cyl. or axis components in my last 2 prescriptions? Otis> Again, small variations. The smallest "prescription" value is in 1/4 diopter increments. It could be that the OD simply rounded "up" or rounded "down" -- depending on the judgment of the OD -- of course. Best, Otis > I've been wearing glasses for about 4 1/2 years now. > [quoted text clipped - 42 lines] > How do you explain no cyl. or axis components in my last 2 > prescriptions? > Otis> None of the measurements are "perfectly accurate". Depending > on measurement conditions, you could see variations of 1/4 to > 1/2 diopter -- depending on the OD making the measurements. Of course. Since his vision changes from morning to evening, it MUST be the OD's measurements that are off. > How do you explain no cyl. or axis components in my last 2 > prescriptions? [quoted text clipped - 3 lines] > rounded "up" or rounded "down" -- depending on the > judgment of the OD -- of course. Of course it has to be the OD's judgement. It couldn't be the cyl that changes. >> So what's going on? Have my eyes changed in 2 months? Do they change >> from day-to-day? Overnight? There are small variations that occur on a diurnal cycle. If your blood sugar is ok, most doctors would not consider your variations anything to worry about. >> How do you explain no cyl. or axis components in my last 2 >> prescriptions? The cyl values in the first rx are as small as they can be without being zero. Cylinder can certainly vary this much over the course of a normal day. -MT, OD Sorry. Rishi Giovanni Gatti (Zetsu), Lena102938, and Otis Brown are trolls who haunt s.m.v. Rishi has published, and is trying to sell worthless books. Otis is pathologically dishonest and actually hurts people. Following his advice can induce double vision in those not working closely with an eye doctor. Lena102938 uses anti-eye doctor rhetoric as a substitute for ANY actual information. It seems she now has to wear glasses and has developed a pathological (and ILLOGICAL) resentment toward the industry that "foisted these glasses upon her." You'd do well to ignore them and wait for responses from the caring, compassionate eye doctors who DO also participate in this site. > I've been wearing glasses for about 4 1/2 years now. > [quoted text clipped - 42 lines] > How do you explain no cyl. or axis components in my last 2 > prescriptions? A camera lens (like the eye) can only be in absolute focus at one distance at any given time. You adjust the focus of a camera lens depending on how far the object is from the film plane. In the human eye, we rely on the muscles surrounding the eye to change the shape of the eye to adjust focus between near and far. However, as you get older, the muscles in your eye are weaker and less flexible, and less able to make the necessary adjustment. That is also why your close-up Rx (add power) increases as you age. Wearing glasses can actually make the muscles even weaker because you are no longer using these muscles as much to accommodate and they deteriorate somewhat from lack of use. By the same token, when you first waken in the morning, the muscles in your eye are less tired than later in the day, and you may be able to accommodate better. Also, you may be squinting when looking at the clock in bed, which increases the depth of focus of your eyes and compensates for the need to focus up-closely, in the exact same way a camera has an increased depth of focus when the lens aperture is made smaller (as the f-stop is larger). > In the human eye, we rely on the >muscles surrounding the eye to change the shape of the eye to adjust focus >between near and far. It's not the "shape of the eye" that changes with accommodation, but the shape of the lens. >However, as you get older, the muscles in your eye are weaker and less >flexible, and less able to make the necessary adjustment. That is also why >your close-up Rx (add power) increases as you age. No, it's not the weakening of the muscles, but the the deterioration of the lens which loses its flexibility and ability to accommodate. >Wearing glasses can >actually make the muscles even weaker because you are no longer using these >muscles as much to accommodate and they deteriorate somewhat from lack of >use. Unfounded and factually incorrect.  SignatureMsBrainy > It's not the "shape of the eye" that changes with accommodation, but the > shape of the lens. The lens is part of the eye. > No, it's not the weakening of the muscles, but the the deterioration of > the > lens which loses its flexibility and ability to accommodate. It is both. That is why a person's eyes can get "tired." A lens does not loose flexibility in a single day. > Unfounded and factually incorrect. Founded and factually correct. I am not suggesting (unlike some others on this newsgroup) that one forgo wearing glasses if they are needed, but one's uncorrected vision does get a little worse if the eye muscles are not used as much. >> It's not the "shape of the eye" that changes with accommodation, but the >> shape of the lens. > >The lens is part of the eye. Usually the "shape of the eye" relates to the shape of the eyeball, not to any particular PART of the eye. Using your logic, you could have said "the shape of the head", which the eye is a part of. Reading your original post my impression was that you related accommodation to adjustments of the shape of the eyeball, and you are not the only one who makes such statements. I have read lots of similar claims on "i-see" message board, as part of the participants efforts to "cure" myopia thru accommodation, which they mistakenly assumed is done by adjusting the shale of the eyeball. SignatureMsBrainy > Usually the "shape of the eye" relates to the shape of the eyeball, not to > any particular PART of the eye. Using your logic, you could have said [quoted text clipped - 11 lines] > shale > of the eyeball. The shape of the eye does affect how well the image is properly focused in the eye. A hyperope (farsighted) person has an eyeball that is too short (too round), and a myope (nearsighted) person has an eyeball which is too long (not round enough). Both of these conditions cause the retina to be in the wrong position relative to the lens. You can blame the shape of the lens or you can blame the length of the eyeball (which determines how far away the retina is from the lens) for the inability to see clearly in these cases. In addition, many people have at least some astigmatism, which is another deformity in the shape of the eye. Obviously, the ability to focus the lens on the retina for both objects close by and objects at a distance also depends on other factors besides the initial shape of the eye, and the ability to see at both distances clearly will change as one gets older (even a person with 20-20 vision when younger will likely need reading glasses when they get older). But the initial shape of the eye is one of the factors. I certainly do not advocate curing any vision problem by forgoing glasses, however, as I stated, it is better for a younger person (IMO) to be slightly under-corrected in many cases. >The shape of the eye does affect how well the image is properly focused in >the eye. A hyperope (farsighted) person has an eyeball that is too short [quoted text clipped - 4 lines] >the retina is from the lens) for the inability to see clearly in these >cases. I am afraid that you mix up presbyopia with hyperopia. They are two distinct different conditions. Presbyopia affects both hyperopes and myopes. The person who asked the initial question on this thread is a mild myope with advanced presbyopia. SignatureMsBrainy > I am afraid that you mix up presbyopia with hyperopia. They are two > distinct [quoted text clipped - 3 lines] > with > advanced presbyopia. I have not mixed up anything. You are the one who is seriously confused. Hyperopes (too short) and myopoes (too long) have mis-shaped eyeballs, despite your pathetic attempts to draw attention away from your prior misstatements, >The shape of the eye does affect how well the image is properly focused in >the eye. A hyperope (farsighted) person has an eyeball that is too short [quoted text clipped - 4 lines] >the retina is from the lens) for the inability to see clearly in these >cases. I am afraid that you mix up presbyopia with hyperopia. They are two distinct different conditions. Presbyopia affects both hyperopes and myopes. The person who asked the initial question on this thread is a mild myope with advanced presbyopia. SignatureMsBrainy >The shape of the eye does affect how well the image is properly focused in >the eye. A hyperope (farsighted) person has an eyeball that is too short [quoted text clipped - 4 lines] >the retina is from the lens) for the inability to see clearly in these >cases. I am afraid that you mix up presbyopia with hyperopia. They are two distinct different conditions. Presbyopia affects both hyperopes and myopes. The person who asked the initial question on this thread is a mild myope with advanced presbyopia. SignatureMsBrainy > >The shape of the eye does affect how well the image is properly focused in > >the eye. A hyperope (farsighted) person has an eyeball that is too short [quoted text clipped - 15 lines] > > Message posted viahttp://www.medkb.com I started wearing glasses/contacts about 15 years ago. The first few years that I went, each time I needed a stronger presciption. Then I went several years where my eyes stayed the same. The last three years that I have gone to the eye doctor, my eyes have gotten better and my presciption has been decreased. Is this a natural process with peoples eyes? > I started wearing glasses/contacts about 15 years ago. The first few > years that I went, each time I needed a stronger presciption. Then I > went several years where my eyes stayed the same. The last three > years that I have gone to the eye doctor, my eyes have gotten better > and my presciption has been decreased. Is this a natural process with > peoples eyes? Your experience is typical for nearsightedness, the same as the population average. -MT, OD > > >The shape of the eye does affect how well the image is properly focused in > > >the eye. A hyperope (farsighted) person has an eyeball that is too short [quoted text clipped - 22 lines] > and my presciption has been decreased. Is this a natural process with > peoples eyes? yes. happens frequently. > I am afraid that you mix up presbyopia with hyperopia. They are two > distinct [quoted text clipped - 3 lines] > with > advanced presbyopia. You also seem to have a severe case of attention deficit disorder since you have posted the same thing 3 times. I would suggest you seek medical attention for your condition. > Wearing glasses can > actually make the muscles even weaker because you are no longer using these > muscles as much to accommodate and they deteriorate somewhat from lack of > use. i thought your explanation of his variations in vision were pretty good but I disagree with the above statement. perhaps this might be true for a hyperope who is early into presbyopia but in the vast majority of cases the use of spectacle correction has no effect on further weakening of the ciliary muscle. >i thought your explanation of his variations in vision were pretty >good but I disagree with the above statement. perhaps this might be >true for a hyperope who is early into presbyopia but in the vast >majority of cases the use of spectacle correction has no effect on >further weakening of the ciliary muscle. Before I posted my previous response I googled "causes of presbyopia" and checked about a dozen of articles on the subject. They all pointed out to loss of flexibility of the lens material, and none suggested the weakening of the ciliary muscle as the cause of presbyopia. One of the articles metioned that there are some other ideas of possible causes, but none has been proven. It seems that the "majority opinion" (vs. "second opinion") of the medical community holds a consensus regarding this matter, although I recall a post by you not too long ago, expressing the "second opinion" speculation (weakening of the ciliary muscle) as the cause. SignatureMsBrainy > Before I posted my previous response I googled "causes of presbyopia" and > checked about a dozen of articles on the subject. They all pointed out to > loss of flexibility of the lens material, and none suggested the weakening of > the ciliary muscle as the cause of presbyopia. One of the articles metioned > that there are some other ideas of possible causes, but none has been proven. hello, the true cause of presbyopia is not known. the assumption that loss of pliability of the lens is the cause was offered up by Helmholtz over a century ago and has been accepted without much verification. in contrast, an alternative theory, and what is currently my favorite, is proposed by Schachar. he suggests that the constant growth of the lens throughout a person's lifetime results in it's growth to a size where the zonule fibers become slack and no longer can effectively pull on the lens and change its shape. according to him the pliability of the lens is not the cause, nor is muscle atrophy, although atrophy occurs as a secondary effect (disuse atrophy). here is a reference to his theory, which is the basis of an experimental surgical technique using scleral expanding bands to reverse presbyopia. for a brief time I worked at a center that was involved in clinical trials for this method so I had an opportunity to understand it's basis fairly well. http://www.emedicine.com/oph/topic723.htm so in a nutshell, the true cause of presbyopia is not known. for many many years students and doctors have been presented with the Helmholtz explanation as if its the gospel truth and if you search the literature on the topic you will find declarative texts that simply assume it. Not so butterfly! anyway, it is definitely clear that ciliary muscle atrophy does indeed occur at approximately the time that presbyopia manifests. that does not necessarily mean that it is the cause of presbyopia-- if ciliary muscle contraction occurs without generating tension on the zonule fibers that connect it to the lens, such as would occur if the lens has grown excessively large, then disuse atrophy would result. regardless of the cause, the ability of the ciliary muscle to compensate for hyperopia clearly is reduced as a person ages. > is a reference to his theory, which is the basis of an experimental > surgical technique using scleral expanding bands to reverse > presbyopia. for a brief time I worked at a center that was involved > in clinical trials for this method so I had an opportunity to > understand it's basis fairly well. Then there's an aspect of Schachar's theory I've never understood. Optically, accommodation happens mostly because the lens thickens. I thought this was accompanied by a decrease in circumference. How does scleral expansion and increased zonular tension promote lens thickening? Doesn't it tend to increase circumference? -MT > <p.clar...@gmail.com> wrote > [quoted text clipped - 13 lines] > > -MT Schacher's "revisionist theory" is not accepted by everyone and there is experimental evidence for and against it. "According to his theory of accommodation, the ciliary muscle contracts and pulls on the equatorial zonules so that the lens moves towards the sclera. This equatorial pull causes the peripheral lens surface to become slightly flatter, but increases the central curvature. This central steepening provides the increase in optical power. Schacher agrees that the lens continues to grow but rather expands outwards in equatorial diameter. In this model, the gap between the lens and the sclera narrows so that the tension that the ciliary muscle and zonules can exert, decreases with age. Eventually the zonules become too loose to pull on the lens and presbyopia develops because the lens can no longer accommodate. Schachar further proposed that presbyopia could be reversed if a surgeon could restore an adequate distance between the ciliary muscle and lens in order to renew tension of the equatorial zonules." When trying to research the best evidence to answer your question I came across this text, which seems rather objective, and covers all the theories quite well. http://www.saoa.co.za/publications/saoptom/2004/jan/journalvol63no1clarkefarr.pdf I'll post more info more directly related to your questions when I find it. > moves towards the sclera. This equatorial pull > causes the peripheral lens surface to become > slightly flatter, but increases the central curvature. > This central steepening provides the increase in > optical power. I can see how that would work, but it seems to me it would affect the resting refraction, more than accommodation. And ciliary contraction should reverse the effect, diminishing net accommodation. Anyhow, assuming that crystalline lenses aren't all shaped the same and they don't all deform the same, that might explain the inconsistent outcomes from the surgery. -MT > <p.clar...@gmail.com> wrote > [quoted text clipped - 13 lines] > > -MT reversal of presbyopia (temporarily) can also be obtained by making several longitudinal incisions in the sclera beginning about 1 mm posterior to the limbus and extending posteriorly for about 10 mm. the depth of the cuts is critical and should be at least 1/2 the thickness of the sclera. it amounts to something like PRK done on the sclera instead of the cornea. it allows the globe to expand slightly and thus recovers some tension on the zonule fibers. patients who have this procedure can recover accommodation for a short while until the continued growth of the crystalline lens again affects zonular fiber tension. and of course there can be complications, so this surgical methods is not performed very much but the mere fact that it has been shown to work supports the Schacher model of accommodation/ presbyopia. if lens sclerosis were causing presbyopia then its recovery via this kind of surgery would not be expected. several years back I left the clinic where the efficacy trials on the scleral expanding bands was underway so I have unfortunately lost contact with the latest word on it's success or failure. it did not seem to me to be a very promising method. less than 10 cases had been performed (at the center I was at, but there were other centers involved also) and in two patients the bands spontaneously extruded from their incisions, while in another patient one eye was lost to endophthalmitis. although the others patients regained some accommodation, its magnitude was variable and frequently diminished and it was seeming as though some kind of training or exercises might be required to fully redevelop it. > I can see how that would work, but it seems to me it would affect the > resting refraction, more than accommodation. And ciliary contraction should > reverse the effect, diminishing net accommodation. actually, the Schacher model says that ciliary muscle contraction during accommodation changes the lens in a way very different than what Helmholtz suggests. Schacher would say that ciliary muscle contractions pulls on the edges of the lens causing it to INCREASE in diameter which flattens the periphery of the lens but causes and increase in curvature of the central lens thus increasing refractive power. the older Helmholtz model suggests that ciliary muscle contraction causes the lens to move forward in the globe allowing the lens to assume a more spherical shape where the diameter DECREASES but lens curvature increases thus producing increased refractive power. the two methods both predicts an increase in lens power Schacher says the lens is stretched while Helmholtz says that the lens relaxes to its natural more spherical shape. See slide 10 in the powerpoint presentation posted at this link: http://academic.sun.ac.za/eye/Old%20Reg%20Talks/PRESBYOPIA2.ppt Some experiments in fact do show that the lens diameter DOES increase during accommodation thus favoring Schacher's idea. Study results on cadaver lenses are mixed on the questions of whether lens sclerosis or decreased pliability really does occur in middle age and whether or not it accounts for presbyopia. I think there two articles are important ones to read to understand the controversy overall. The jury appears to still be out but Helmholtz's theory still seems to have some life in it. Schacher is "going for the gold" by trying to solve presbyopia via refractive surgery but it isn't working out so easily. Schacher RA. Zonular function: "A new hypothesis with clinical implications". Annals of Ophthalmology 1994 26(2) 36-38. Glasser A, Kaufman PL. "The mechanism of accommodation in primates". Ophthalmology 1999 106, 863. > i thought your explanation of his variations in vision were pretty > good but I disagree with the above statement. perhaps this might be > true for a hyperope who is early into presbyopia but in the vast > majority of cases the use of spectacle correction has no effect on > further weakening of the ciliary muscle. Thank you. It was aimed for a consumer, not for someone who is in the optical professions. Those in the optical professions will probably continue to nitpick it, even if that does not help the patient better understand their vision. Since I am hyperope, I can say with personal experience that wearing glasses can be slightly addictive in terms of loosing the ability to accommodate. This is especially true for patients who are younger than the OP so perhaps you are correct that it may not be a significant factor in this case. But I suspect could be a slight factor. However, by no means I am aligning myself with the quacks on this newsgroup who advocate not wearing glasses for this reason. But I do believe that is better to slightly under-prescribe than to slightly over-prescribe (which is a common problem for hyperopes IMO). > Since I am hyperope, I can say with personal experience that wearing glasses > can be slightly addictive in terms of loosing the ability to accommodate. you are the type of patient I referred to as the possible exception. hyperopes who are approaching middle-age have reduced ciliary muscle capacity. Plus lenses, which sometimes cause visual complaints in younger patients particularly at distance, all of a sudden can become "appreciated." if that's you, then all I can say is-- it will get worse. its not the glasses doing it-- its your eyes aging. On Oct 18, 4:06 am, p.clar...@gmail.com wrote: > > Since I am hyperope, I can say with personal experience that wearing glasses > > can be slightly addictive in terms of loosing the ability to accommodate. [quoted text clipped - 5 lines] > "appreciated." if that's you, then all I can say is-- it will get > worse. its not the glasses doing it-- its your eyes aging. FROM: http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=915798 1. Apparatus has been designed to alter the shape of the human lens by tensile forces applied to the zonular fibres indirectly through the ciliary body. The changes in dioptric power of the lens for monochromatic sodium light were measured at the same time. Simultaneous serial photography, and direct measurement enabled one to relate a change in shape of the lens to the change in dioptric power. Subsequently, the same lens was isolated and spun around its antero- posterior polar axis and high speed photography recorded its changing profile. 2. By comparing the changes in lens profile due to zonular tension and centrifugal force respectively, the force developed in the zonule for a given change in the shape of the lens could be calculated. Changes in dioptric power associated with those of shape can thus be related directly to the force of contraction of the ciliary muscle necessary to reduce the initial tension of the zonule in the unaccommodated state. 3. The force of contraction of the ciliary muscle as measured by radial force exerted through the zonule and the change in dioptric power of the lens were not linearly related. The relationship is more exactly expressed by the equation [Formula: see text] where D = amplitude of accommodation in dioptres (m-1), FCB = force of contraction of the ciliary muscle as measured by changes in tension of the zonule (N), Kdf = dioptric force coefficient and is constant for a given age (m-1N-? ? 102?5). This coefficient is 0?41 at 15 yr and 0?07 at 45 yr of age. 4. In youth for maximum accommodation (10-12 D) the force is approximately 1?0 ? 10-2 N while to produce sufficient accommodation for near vision (3?5 D) the force is less than 0?05 ? 10-2 N. 5. After the age of 30 yr the force of contraction of the ciliary muscle necessary to produce maximum accommodation rises steadily to about 50 yr of age and thereafter probably falls slightly. At about 50 yr of age the ciliary muscle is some 50% more powerful than in youth. 6. Even if hypertrophy of the muscle did not occur the amplitude of accommodation would be reduced at the most by only 0?8 D of that observed at the onset of presbyopia >So with the eyes any change in vision is possible. Yes all functional and organic troubles of the eye are not only changeable, but also curable in their entirety. It is only required that a person practices intelligently the methods of rest and demonstrates that his sight can spontaneously return when he sees without effort or strain. Sorry. Rishi Giovanni Gatti (Zetsu), Lena102938, and Otis Brown are trolls who haunt s.m.v. Rishi has published, and is trying to sell worthless books. Otis is pathologically dishonest and actually hurts people. Following his advice can induce double vision in those not working closely with an eye doctor. Lena102938 uses anti-eye doctor rhetoric as a substitute for ANY actual information. It seems she now has to wear glasses and has developed a pathological (and ILLOGICAL) resentment toward the industry that "foisted these glasses upon her." You'd do well to ignore them and wait for responses from the caring, compassionate eye doctors who DO also participate in this site. > Yes all functional and organic troubles of the eye are not only > changeable, but also curable in their entirety. blah blah blah why did you interject your homeopathic voodoo crap into this thread? relaxation, sunning, yoga, and Ravi Shankar music, or whatever other bullcrap you want to propose, has NO EFFECT on presbyopia. why would you expect any of us to believe that some pimple-faced naive 15 year old kid knows how to cure presbyopia. go away. you are irrelevant to any learned conversations about the eye. you barely just learned how to spell it a couple of years ago and now you think you have all the answers. just from personal experience I kinda went through the same thing. I had PRK on my -10 vision. I am back to wearing glasses/contacts. I had my surgery last year and my vision has changed about 4 times over the summer, but ever so slightly. I am somewhere around -0.75, -0.25. That's better then it's been in my entire life and I am grateful for that. I still have to go back...but I am waiting to see if my eyes get worse. 3 % chance that can happen and I am just unlucky that way. My mother on the other hand is 56 years old and her vision actually got better! you would think with age it would worsen. So with the eyes any change in vision is possible. Nice group you got here. Not many answers to be found. Thanks to Otis and Mark A for at least taking a shot at it. No one attempted to answer Katz24's either. Just a lot of bickering and one-upmanship. SO... Have my eyes changed in 2 months? Do they change from day-to-day? Overnight? And no, Mark, I'm not squinting when I wake up in the morning and can see the numerals on my digital clock with clarity. > Nice group you got here. Not many answers to be found. Thanks to Otis > and Mark A for at least taking a shot at it. Mark A did fine. In the case of Otis, you're in trouble if you think that WRONG answers are better than NO answers when it comes to vision and health. Good luck! > Nice group you got here. Not many answers to be found. Thanks to Otis > and Mark A for at least taking a shot at it. [quoted text clipped - 10 lines] > And no, Mark, I'm not squinting when I wake up in the morning and can > see the numerals on my digital clock with clarity. You are asking something no one can answer! No one can diagnose you or your visual acuity over the internet, nor should you rely on medical advice from strangers on the internet. You never know who is lurking behind the words you are reading or what their qualifications or intentions are. If you have questions, then you should go see an optometrist or an ophthalmologist, or your general practitioner. Only in person can a doctor take proper measurements of your eyes and be able to answer your questions. There may be some underlying medical condition. It could simply be that you have dry eyes which can cause visual acuity to fluctuate. Are you a woman entering menopause? Dry eyes is a common complaint of post-menopausal women. You've verified that your glasses were made to spec, but obviously your impression is that your eyes have changed. Go get it checked out by a doctor. How can anyone possibly tell you if your eyes are changing "overnight" without examining you? Your expectations of what kinds of "service" this newsgroup provides are unrealistic. You thought you'd get some "free" advice instead of seeing a medical professional? Well, you get what you pay for! Signature~RT > On Oct 18, 3:25 pm, RT <RTM...@NOSPAMyahoo.com> wrote: > You are asking something no one can answer! > > No one can diagnose you or your visual acuity over the internet, nor > should you rely on medical advice from strangers on the internet. I wasn't asking for a diagnosis. I suppose I should have framed the question genericly--Can a person's eyes change day-to-day? > If you have questions, then you should go see an optometrist or an > ophthalmologist, or your general practitioner. Only in person can a > doctor take proper measurements of your eyes and be able to answer your > questions. My optometrist said he didn't know why the grocery store effect could be happening and he offered that I saw the clock in the morning in focus because my eyes had been relaxed from sleeping. > You've verified that your glasses were made to spec, but obviously your > impression is that your eyes have changed. Go get it checked out by a > doctor. How can anyone possibly tell you if your eyes are changing > "overnight" without examining you? Think about it. I would need to have two eye exams within a day or two of each other. Now I'm out $500 and suppose the doctor says, "yeah there is a slight variation." Now what? Buy another pair of glasses for Mon-Wed-Fri? I just should have asked a generic question as to the possibility of this sort of phenomena happening. I simply wanted to know if someone's eyes could change, not necessarily if mine were doing so. >Your expectations of what kinds of > "service" this newsgroup provides are unrealistic. You thought you'd get > some "free" advice instead of seeing a medical professional? Well, you > get what you pay for! Yeah, there are some seriously mixed up people on here! > I just should have asked a generic question as to the possibility of > this sort of phenomena happening. I simply wanted to know if someone's > eyes could change, not necessarily if mine were doing so. Did you give any consideration to the possibility of dry eyes that I mentioned in my post? Dry eyes can cause visual acuity to fluctuate minute to minute. There are a lot of environmental, hormonal and disease factors that can bring on dry eyes. Neil Brooks on this NG can offer some advice on dry eyes from his personal experience. But a simple way to check would be to put preservative free eye drops in your eyes when things look blurry, blink a few times and see if things clear up. That will cost you considerably less than $500 (well, at least with the first bottle). Signature~RT > On Oct 19, 9:02 am, RT <RTM...@NOSPAMyahoo.com> wrote: > Did you give any consideration to the possibility of dry eyes that I > mentioned in my post? Dry eyes can cause visual acuity to fluctuate [quoted text clipped - 5 lines] > will cost you considerably less than $500 (well, at least with the first > bottle). Thanks, but I don't think it is dry eyes. I wouldn't describe my symptoms as blurry vision, just not as sharp as it could be. The grocery store signs is a good example. Let's say one of them is about 100 feet away. Some days I can read it clearly, other days I can read it, but not crystal clear. Everything within about 75 feet is in sharp focus every day. I'm probably going to print up my own personal Snellen chart and tape it to a wall in my house, then find a spot where I have trouble discerning smaller letters with my glasses on and test it everyday. See if my vision changes. At least I would have some objective data to work with. "powrwrap" <powrwrap@aol.com> wrote in message > Have my eyes changed in 2 months? > Do they change from day-to-day? > Overnight? Your eyes can change from hour to hour depending on how tired they are and your general health. A .25 diopter change is not significant and there might be that much variation in eye exams even if given by the same person back to back, not to mention if they are given by different providers. The exact Rx can easily depend on the thoroughness of the optometrist or how careful the patient is when answering (which is better, 1 or 2). In addition, the Rx can depend on the philosophy of the provider in how much correction you should be given based on their interpretation of your specific needs (especially in the near vision area). Furthermore, since you have progressives, even the slightest shift in how the frame sits on your face can have a significant effect on your vision. However, this can mitigated by getting a progressive using an advanced lens design, a high quality material with high abbe value (not polycarb and not super-high index), and a proper fitting by a trained professional. > And no, Mark, I'm not squinting when I wake up in the morning and can > see the numerals on my digital clock with clarity. Just asking. > On Oct 18, 8:28 pm, "Mark A" <nob...@nowhere.com> wrote: > Your eyes can change from hour to hour depending on how tired they are and > your general health. A .25 diopter change is not significant and there might [quoted text clipped - 12 lines] > design, a high quality material with high abbe value (not polycarb and not > super-high index), and a proper fitting by a trained professional. >< APPLAUSE! >< Thank you Mark. Exactly the sort of answer I was looking for. God bless you. > > On Oct 18, 8:28 pm, "Mark A" <nob...@nowhere.com> wrote: > > Your eyes can change from hour to hour depending on how tired they are and [quoted text clipped - 17 lines] > Thank you Mark. Exactly the sort of answer I was looking for. God > bless you. could you be diabetic or have a thyroid dysfunction? > Nice group you got here. Not many answers to be found. Thanks to Otis > and Mark A for at least taking a shot at it. [quoted text clipped - 3 lines] > > SO... If you went to sci.med.diseases.cancer and asked for a home cure for cancer, using available household products, you probably wouldn't get any good answers. That doesn't mean they don't care, just that they don't have any answers. If you ask Otis for a cure for cancer, I suspect that you will get his one answer: look at a Snellen chart and wear OTC reading glasses. Dear Dan, Subject: Sorry you make so many false assumptions. Dan> If you ask Otis for a cure for cancer, I suspect that you will get his one answer: Otis> You would get the recommendation from me to go to a medical doctor of John's Hopkins for treatment. Dan> ...look at a Snellen chart and wear OTC reading glasses. Otis> Again, the recommendation would be that the person should have a MEDICAL exam looking for a drop in visual-acuity -- that must be associated with a retina problem. ONLY AFTER THERE IS NO MEDICAL PROBLEM -- AND AFTER THIS TYPE OF REVIEW -- should the PREVENTIVE second-opinion be considered. Otis> This would be a review with the parent and child of these issues -- once the ANY MEDICAL PROBLEM EXISTS. Otis> Then I would suggest that the parents be sent to a second-opinion (behaviorial) optometrists -- who supports PREVENTION on the threshold -- like our friend Steve Leung does: www.chinamyopia.org (And other similar professional sites.) Otis> Are we clear on this logical sequence? Otis > In article <1192736529.320985.170...@q5g2000prf.googlegroups.com>, > [quoted text clipped - 13 lines] > If you ask Otis for a cure for cancer, I suspect that you will get his > one answer: look at a Snellen chart and wear OTC reading glasses. Subject: Finding the RIGHT prevention-minded optometrist The optometrist who his most likely to be sensitive to your child's need for true-prevention -- it the optometrist who has in fact, "objected" to the over-prescribed minus, and cleared her vision back to normal by her own efforts. She is a true professional. But it is important to understand the wisdom of not letting your distant vision go to hell in the first place -- and have to go through the effort to clear back from -4 diopters as she did. It also depends on how much you value keeping your distant vision clear for life. It is true that a lot of people simply do not have the motivation to make the PREVENTIVE methods effective for themselves. See: http://www.optometrists.org/Boston/articles.html for second-opinion details on how to do this. Enjoy, Otis On Oct 19, 9:30 pm, "otisbr...@pa.net" <otisbr...@pa.net> wrote: > Dear Dan, > [quoted text clipped - 50 lines] > > - Show quoted text - > I've been wearing glasses for about 4 1/2 years now. > [quoted text clipped - 42 lines] > How do you explain no cyl. or axis components in my last 2 > prescriptions? Do you noticed that your adds bigger ? Just progressives spoiled you vision. > Just progressives spoiled you vision. really? and how do progressives spoil a person's distance vision? please provide a rational explanation on a detailed level involving the anatomy and physiology of the eye that accounts for the "spoilage" that you claim. my guess is you have no explanation-- just a blind faith that it happened to you (for a different reason that you don't comprehend) so therefore you generalize it to be a problem that everyone has. furthermore you believe its probably a capitalist conspiracy to hook people on lenses that damage their eyes so large profit-seeking companies can sell glasses. >1. I have a digital alarm clock on my dresser about 10 feet from where >I sleep. The numerals are about 3/4 of an inch high. When I look at >the clock a few minutes after retiring, with the lights off, the >numbers are not in focus. However when I wake up in the morning I can >read the clock perfectly. Crystal clear. This is the only one I can answer with confidence. The key factor here is darkness. In the dark room, your pupils are wide open, to let in as much light as possible. This means that more of your cornea and lens are involved with bending light to focus on your retina. If you're familiar with manual-focus cameras, it's like turning the f-stop all the way down, so the aperture is as wide as it gets. The result is that depth of field (the range of distance at which objects appear in focus) goes down, so you'll have a narrower range of in-focus vision, which is centered at a distance of a little more than four feet from your eyes. In the morning, when it's light in the room, your pupils close up. Aperture goes down, and depth of field goes up, to the point where your clock is near enough to appear in focus. That's because most of the rays of light that make it to your retina are bent very little, as they pass through mostly the middle of your cornea and lens. The same principle is why you can see clearly through a tiny hole in a piece of paper (provided there's enough ambient light), and why pinhole cameras actually work. Signature- Mike Ignore the Python in me to send e-mail. |
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