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Medical Forum / General / Vision / March 2005The theory behind starburst (or other glare problems)
Hello, I have been in a LASIK surgery and have been studying related knowledge to some extent. But so far I haven't found information on how starburst effect is formed in eye optics. What is the exact theory behind it and where can I study about it? Camera optics is ok too if information is more easily found in that area. To make the question clearer, I'm curious how one burst or arm or ray is formed, why is it in that particular position and not evenly 360 degrees around the object forming a solid field? WOW GOOD QUESTION! have you noticed that NOBODY with perfect sight has this problem? Only people with glasses have that. Obviously the problem is not in the eye but in the mental strain of the imperfect sight AND the glasses. http://TheCentralFixation.com > Hello, > [quoted text clipped - 7 lines] > formed, why is it in that particular position and not evenly 360 degrees > around the object forming a solid field? > have you noticed that NOBODY with perfect sight has this problem? Well, a person with perfect sight doesn't have problems with his sight. > Only people with glasses have that. Glasses usually produce only minor glare distortion (compared to eye problems). > Obviously the problem is not in the eye but in the mental strain of > the imperfect sight AND the glasses. The eye is a mechanical device with living tissue and a bunch of nerve cells. If the mechanical device is faulty, it will certainly be more difficult for the brain to translate the picture in the best possible way. > > have you noticed that NOBODY with perfect sight has this problem? > > Well, a person with perfect sight doesn't have problems with his sight. So what is the explanation for imperfect sighted people? Do you really believe in something physical? Then why it cannot be found? > > Only people with glasses have that. > > Glasses usually produce only minor glare distortion (compared to eye > problems). That's why glasses are not a solution, ever! > > Obviously the problem is not in the eye but in the mental strain of > > the imperfect sight AND the glasses. > > The eye is a mechanical device with living tissue and a bunch of nerve > cells. If the mechanical device is faulty, it will certainly be more > difficult for the brain to translate the picture in the best possible way. What is the "mechanical device"? > Do you really believe in something physical? > > Then why it cannot be found? Who says it cannot be found? I already know the answer to my question partly, but I need further information to fill the gaps. What do you think causes distorted vision then? The mind? And the optical system of the eye does not have a problem? Of course the mind is the most important part of the seeing process, but certainly if the eye is not well, the picture will be send to the brain imperfectly. > That's why glasses are not a solution, ever! So, do you have a refractive error which you can subconsciously correct with the mind? How many diopters? > What is the "mechanical device"? If you don't consider the eye as a whole a mechanical device, do you consider the cornea or the crystalline lens to be mechanical parts (well they're not totally mechanical, they are living tissue - but still they have very much the same qualities as if they were made of glass for example)? > does not have a problem? Of course the mind is the most important part of > the seeing process, but certainly if the eye is not well, the picture will > be send to the brain imperfectly. when you say THE MOST you need to understand THE VERY MOST ABSOLUTELY. now, even with this defective understanding of yours, THE MOST means that the mind has MORE part in vision than the eye... and still you go after these idiots doctor who treat only the eye MISTREATING IT and do not know anything about the rest? > > That's why glasses are not a solution, ever! > > So, do you have a refractive error which you can subconsciously correct with > the mind? How many diopters? People are getting a cure from -23 D. I'm witnessing it and it is going very well. Slowly but unbelievable. > > What is the "mechanical device"? > > If you don't consider the eye as a whole a mechanical device, do you > consider the cornea or the crystalline lens to be mechanical parts (well > they're not totally mechanical, they are living tissue - but still they have > very much the same qualities as if they were made of glass for example)? No quality at all like the glass, of course, all living and all SUBSERVIENT to the mind. Unless you understand this, you won't go anywhere. > People are getting a cure from -23 D. > I'm witnessing it and it is going very well. > Slowly but unbelievable. Well. As the picture absolutely away from anything recognizable at -23 D, I would say that it is impossible for the mind to calculate a real picture out of that. So, there has to be a drastic physical change in the eye. The three important parts are the cornea, the pupil and the crystalline lens. The crystalline lens even has muscles around it and the iris around the pupil is a muscle itself. In practice, this person would see better if the pupil was contracted and the crystalline lens got some miraculous power to extend to unnatural positions. > > People are getting a cure from -23 D. > > I'm witnessing it and it is going very well. [quoted text clipped - 8 lines] > contracted and the crystalline lens got some miraculous power to extend to > unnatural positions. The girl can focus half a mm letter at 18 cm. What do you think? It is clear that the eye is turning back to its normal shape, being the elongation of the myopia simply disappearing over time. Also that same girl can focus at 5 feet a letter calibrated to be read at 10 feet. What do you think? > It is clear that the eye is turning back to its normal shape, being the > elongation of the myopia simply disappearing over time. Yes, that is in a way the simplest solution if for example the person was born with a good sight but then the eye extended in shape. It just went back. What is the success rate at this Bates thing? If it's really low, then it can be that it doesn't have any effect in reality but the eye heals itself sometimes. As to looking at sun, I don't understand why it would help. Yes, certainly looking at light reduces the size of pupil which means that focus gets better and depth of field becomes so that you can see better near and far at the same time. That can make the illusion of looking at light helps if you don't realize it's just momentary. But like in ear, if you have too loud sound you will just destroy your cells eventually. > > It is clear that the eye is turning back to its normal shape, being the > > elongation of the myopia simply disappearing over time. [quoted text clipped - 4 lines] > it can be that it doesn't have any effect in reality but the eye heals > itself sometimes. Why low? It's 100% success. But you have to do it. And you cannot do it with glasses on. So first thing you have to discard glasses. > As to looking at sun, I don't understand why it would help. Yes, certainly You speak as if you can understand things. You cannot understand. Just do it and it cures. To do it you have to discard glasses, otherwise it won't work and you cannot do it. > looking at light reduces the size of pupil which means that focus gets > better and depth of field becomes so that you can see better near and far at Again you speak of things you do not understand. Just do an experiment. Lit a candle and look at it with a mirror so you can check the pupil size. You will see that if you look into the flame, the pupil contracts, even if the flame is very low. You do the experiment and then tell me. > the same time. That can make the illusion of looking at light helps if you > don't realize it's just momentary. But like in ear, if you have too loud > sound you will just destroy your cells eventually. Now you talk to this girl who is a biologist, doctorate, and let her explain to you how he is curing her eyesight. Your discussion are just a show of ignorance of the facts. > So first thing you have to discard glasses. For the record, I don't use glasses, my eyes are LASIK operated. But tell me how long time does a person with bad vision have to be without glasses - how quickly will the eye heal itself with the Bates method? If it's a long time, who can afford to be half blind for a long time? > You speak as if you can understand things. > You cannot understand. > Just do it and it cures. What ever method there is, if it works, it can be scientifically explained and it can be understood. Of course the operation of brain isn't fully understood yet (not even close), but certainly eye optics (or even the visual operations of brain) don't include anything out of this world. > Lit a candle and look at it with a mirror so you can check > the pupil size. > > You will see that if you look into the flame, the pupil contracts, > even if the flame is very low. What is the point of this experiment? Yes, the pupil contracts when more light is coming in. > > So first thing you have to discard glasses. > > For the record, I don't use glasses, my eyes are LASIK operated. But tell me > how long time does a person with bad vision have to be without glasses - how > quickly will the eye heal itself with the Bates method? If it's a long time, > who can afford to be half blind for a long time? Can you tell how time a student can devote to the study of a subject, in advance? If the student is intelligent, the time needed is very short. If the student does not study, the time will become very long, if ever. Now if you are unable to use your eyes properly, you have to learn how to do it, and this may take time. In few minutes you will have much TEMPORARY improvement, like a flash of perfect sight if you happen to find FAVOURABLE conditions. For the PERMANENT cure, time is usually very long for people who have adopted glasses steadly. One year, two years, three years, but in the meanwhile the vision is always better day by day, and always perfect or nearly perfect in sunlight and other good conditions. Then, conditions variate so much as many individuals are on the Earth. > What ever method there is, if it works, it can be scientifically explained > and it can be understood. Of course the operation of brain isn't fully > understood yet (not even close), but certainly eye optics (or even the > visual operations of brain) don't include anything out of this world. When you say "not even close", think as if ophthalmology is not even close to understand anything. Eye optics is irrelevant. The master mind is in the brain. Discard eye optics, it is only a waste of time. > > Lit a candle and look at it with a mirror so you can check > > the pupil size. [quoted text clipped - 4 lines] > What is the point of this experiment? Yes, the pupil contracts when more > light is coming in. The point is that even in very LOW LIGHT a simple flame makes the pupil contract. So there is not much difference when you are outside in the open unders the sun. But if you had had LASIK, just wait a few months, you will start to have problems again, then you may become interested in the true cure, since the LASIK is just cheating. http://TheCentralFixation.com > If the student is intelligent, the time needed is very short. Ok let's say I'm very smart. If the technique still takes a lot of time, say months, I'm not able to use it as I have to be able to read music score for example perfectly, I can't make compromises. > Then, conditions variate so much as many individuals are on the Earth. Well, LASIK is probably more efficient means in many cases then (or glasses). Although it has its drawbacks, at least with today's technology. > When you say "not even close", think as if ophthalmology is not even > close to understand anything. Physics may also be very far away from undestanding it all, but physics still gives us valuable applications we use every day (television, phone etc.). > The point is that even in very LOW LIGHT a simple flame makes the > pupil contract. This is probably because the retina is adjusting as well (not just the pupil and crystalline lens). How does it make the Bates technique more understandable if in low light a flame makes the pupil contract? > But if you had had LASIK, just wait a few months, you will start to > have problems again, then you may become interested in the true > cure, since the LASIK is just cheating. LASIK is not cheating, majority of LASIK patients are happy with the results. Usually when time passes after LASIK, the result will get better and not the other way around. > Hello, > [quoted text clipped - 7 lines] > formed, why is it in that particular position and not evenly 360 degrees > around the object forming a solid field? Sorry you got that nut case who responded to you. Starburst in post lasik patients is a higher order visual aberration usually due to corneal haze or induced by the flap. Usually seen with individuals with dilated pupils at night. Hope this helps. frank > Sorry you got that nut case who responded to you. I must say that there may be some truth in what he says even it sounds totally nut.. I believe it hasn't been scientifically worked out how the glare problem exactly diminishes after LASIK surgery (but there is of course a scientifical explanation, it just hasn't been found yet). And this is what I'm most curious about. What changes when improvement occurs - is it the cornea, the pupil, the mind or what? > Starburst in post lasik patients is a higher order > visual aberration usually due to corneal haze or > induced by the flap. Usually seen with individuals > with dilated pupils at night. Hope this helps. Actually with LASIK, I don't think it's usually due to corneal haze or flap aberration. I think it is mostly because of refractive error at the edge of cornea. What I'm looking for is the theoretical explanation to optics, how exactly do the light rays refract. Obviously starburst differs from basic non-focus, but how? > I think it is mostly because of refractive error > at the edge of cornea. A more accurate description: It is mostly because of refractive deviance at the edge of the optical zone of cornea. (Although the "badly" refracting area extends to the very edge of the cornea as well.) Interesting problem. I recall a case of a patient whose chief post-LASIK complaint was starburst. He was undercorrected, and eyeglasses seemed to diminish all except the starburst. Subsequently, during the examination, I also discovered that he had some residual glare as well. His togographical maps were significant for decentered ablations. He was essentially looking through the bottom part of the treatment zones, which left some of the under-treated cornea within the pupillary aperture. The patient said that this explanation made sense, because he could make the starbursts go away if he tilted his head back, which caused the lower lid to obstruct the under-ablated areas. In wavefront language, coma may be the closest description of this type of aberration. Another illustration is that of an eye with simple myopic astigmatism, and how the image is distorted in an orientation corresponding to the axis of the astigmatism, and symmetrical. DrG > was essentially looking through the bottom part of the treatment zones, > which left some of the under-treated cornea within the pupillary > aperture. Thanks.. I've wondered about that. I still wonder whether it's surface contour or loss of transparency at the scar. If there's a scar. I've seen several that would slip right past a cursory SL exam. -MT > > was essentially looking through the bottom part of the treatment zones, > > which left some of the under-treated cornea within the pupillary [quoted text clipped - 9 lines] > > -MT The flap was symmetrical with respect to the pupil. The decentration wasn't. Also, the starburt was completely resolved with an RGP contact lens. So, with that considered, it probably isn't loss of transparency at the scar. However, flap fibrosis was clearly visible everywhere but the hinge on these Intralase-created flaps. DrG > So, with that considered, it probably isn't loss of > transparency at the scar. I think there can be about 3 layers of bad picture superimposed on the good picture. The worst may be the starburst layer. Similar (same blur diameter) effect, halo, is the same thing, just spread more evenly. The distorted layers may be caused by different physical problems. But the biggest problem is the refractive deviance at the edge of the optical zone. This happens even without decentration. The picture gets much better when aperture size is reduced (for example if looking down with tilted head). > Also, the starburt was completely resolved with an RGP > contact lens. What is the explanation to this? Was it not resolved with other kind of contact lens? Does anyone know of any attempt to simulate LASIK operated eye optics? And the theory behind starburst, where should I ask or look for information about this in case the answer should not be found in this news group? > > So, with that considered, it probably isn't loss of > > transparency at the scar. [quoted text clipped - 16 lines] > the theory behind starburst, where should I ask or look for information > about this in case the answer should not be found in this news group? To my knowledge, nobody has tried to simulate LASIK operated eye optics. However, LASIK induced aberrations have been studied in terms of optical theory. This link should get you started: http://research.opt.indiana.edu/Library/AberrationsPostLASIK/AberrationsPostLASI K.html Good luck. DrG > This link should get you started: Thank you. It contained some good new information for me. I wonder why they took a patient with such a small max pupil size. And I couldn't find a date of experiment (it is obviously after 2000 though). I will try to find more work on the subject and investigate further. > Another illustration is that of an eye with simple myopic astigmatism, > and how the image is distorted in an orientation corresponding to the > axis of the astigmatism, and symmetrical. > > DrG What if the man could have been instructed in resting his eyes for half an hour and the try again seeing normally, not tilting the neck, and he was successful? I have heard of several cases of this kind. I have a client who did laser operation five years ago. He tells that in the morning the sight is much better than in the evening. Now you please explain. What happens from morning to night? Then he complains that he has NO MENTAL IMAGES WHATEVER. If he looks at a letter and then tries to remember it with closed eyes, he is BLANK. This is a clear sign of imperfect sight due to mental strain and not to refractive error (the refractive error is supposed to have been corrected by the laser). Now you please teach me how to restore mental imagery and visual remembering. Thank you. > I have a client who did laser operation five years ago. > > He tells that in the morning the sight is much better than in the > evening. I bet this is simply because he wakes up with bright sun light and in the evening the sun is not there. The huge difference between luminance level of course affects the high level aberrations. > If he looks at a letter and then tries to remember it with closed > eyes, he is BLANK. If the Bates technique involves the usage of subconscious and memory, you should talk about them openly and not like it was some kind of wizardry. Unless of course if you don't even understand what the Bates thing is and you just sell it, which is the impression I'm getting (I don't know whether there is truth in the technique itself or not). > > Sorry you got that nut case who responded to you. > [quoted text clipped - 17 lines] > do the light rays refract. Obviously starburst differs from basic non-focus, > but how? Interesting problem. Yesterday I consulted with a patient whose chief post-LASIK complaint was starburst. He was undercorrected, and eyeglasses seemed to diminish all except the starburst. Subsequently, during the examination, I also discovered that he had some residual glare as well. His togographical maps were significant for decentered ablations. He was essentially looking through the bottom part of the treatment zones, which left some of the under-treated cornea within the pupillary aperture. The patient said that this explanation made sense, because he could make the starbursts go away if he tilted his head back, which caused the lower lid to obstruct the under-ablated areas. In wavefront language, coma may be the closest description of this type of aberration. Another illustration is that of an eye with simple myopic astigmatism, and how the image is distorted in an orientation corresponding to the axis of the astigmatism, and symmetrical. DrG > What I'm looking for is the theoretical explanation to optics, how exactly > do the light rays refract. Obviously starburst differs from basic non-focus, > but how? You may ask to your colleagues in the university about the BELL THEOREM. Perhaps there is something more behind your little "scientific" mind. How can you be so "relaxed" with the teaching of all the learned men who have simply destroied your eyesight so that you must depend on all sorts of drugs and lenses and whatever? > You may ask to your colleagues in the university about the BELL > THEOREM. What does the Bell theorem have to do with vision? > How can you be so "relaxed" with the teaching of all the learned > men who have simply destroied your eyesight so that you must > depend on all sorts of drugs and lenses and whatever? Do you realize that you talk really fanatically and you sound like you're trying to defend a religion or something? If the Bates thing should work, isn't it just a technique, nothing more, nothing less? And why is this Bates thing so commercial? Shouldn't information like this be simply free? And I myself don't have to take drugs or use lenses (pupil contractor would help, but at the moment I'm ok as is). |
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