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Astigmatism

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Cactus Jack 18 May 2017, 21:39

Maria Et,

Here is a slightly edited version of the prescription you posted:

OD (right eye) Sphere +5.50, Cylinder -4.25, Axis 170 degrees

OS (left eye) Sphere +5.75, Cylinder -3.25, Axis 165 degrees

I listed the right eye first because that is the way prescriptions are usually written.

The Sphere number indicates that your BF has Hyperopia which is the medical name for Far or Long sightedness. Hyperopia is typically caused by a mismatch between the total PLUS power of his eye's lens system and the length of his eyeballs. Almost every baby is born with Hyperopia. That is because the eyeballs have to be small to fit in the small eye sockets in the baby's head. Fortunately, babies also have incredible accommodation, which they learn to use after about a month. This enables them to compensate for their Hyperopia. As the baby grows their eyeballs also grow and they typically become less Hyperopic. Eyeball growth is believed to be controlled by the genes. Some children's eyeballs grow too much and they become Myopic. Others don't grow quite enough and they remain Hyperopic. As they get older it becomes harder to focus close even focus for distance and they need external PLUS help to focus for distance and near. BTW the distances involved are small. About 0.3 mm per diopter which means that your BF's eyeballs are about 2 mm shorter than ideal.

Your BF's real problem is Astigmatism as indicated by the need for significant Cylinder correction. Astigmatism is usually caused by uneven curvature of the front surface of the Cornea. The curve is steeper in one direction that it is in the other. If you can imagine it, his corneas are shaped like a section from an American Football.

The problem with Astigmatism is that you have no way to correct it without using external lenses (glasses or contacts) or sometimes it can be corrected by surgery. The biggest problem with Astigmatism is that it affects Visual Acuity at ALL distances. Uncorrected Astigmatism make Text very fatiguing to read. If your BF did not have any Astigmatism, he might be able to not wear his glasses for distance, but it would be fatiguing and he would probably have headaches.

The Axis number is ALWAYS required if a person has any Cylinder correction. That number is direction of the Long Axis of the Cylinder. By tradition. 0 degrees is Horizontal. 90 Degrees is Vertical. Looking at the wearer, the numbers increase in a counter-clockwise direction from 0 thru 90 and on around to 179. 180 is the same as 0.

He may be able to function without his glasses, but he can function much better and more comfortably, with them.

Hope this helps you understand. It might be possible for you to experience what he sees without his glasses if you know a friendly Optometrist or Optician. Do you wear any form of vision correction?

C.


Maxim 18 May 2017, 14:49

to Jenny

my sincere best wishes, and my gratulation!

You have been a tough woman, and now you are rewarded with superb vision!


Soundmanpt 18 May 2017, 14:05

Jenny

You were clearly stunned and shocked when you put your glasses on for the very first time. You're eyes really adjusted to them quite fast which of course was good for you. Now that you have your glasses you already seem reluctant to take them off. The added bonus besides being able to see so well is that you shouldn't be bothered by anymore headaches. And even though your eyesight is already greatly improved just wait until your eyes have fully adjusted to your glasses. things will even be sharper and clearer than they are now. If you find that you need to remove your glasses in order to read small print after your eyes have adjusted then you almost certainly will benefit from progressives down the road as the doctor suggested. But for now your glasses should make things about 95% better for you.The progressives will make it a full 100% better.

So it seems you're not having any problem with getting used to wearing glasses. That can sometimes be a bigger issue for some. What comments have you gotten so far about your wearing glasses? Since you're new to wearing glasses and that makes it hard to really know if they are as comfortable as they should be. You just need to know that if you find yourself pushing your glasses up quite bit because they are sliding down your nose or if the earpieces feel a little too tight behnd your ears you should stop at anyplace that sells glasses and have the, adjust them for you. They don't care taht your glasses came form another shop and there won't be any charge. You want your glasses to be completely comfortable to the point that you soon will hardly even think about the fact that you're wearing glasses. Do you have any questions about your glasses or eyesight?


Jenny 18 May 2017, 13:36

I picked up my glasses from Foreyes today and all I can say is OH MY GOD! While I did feel a little queasy at first, that feeling went away within a half hour or so. I can't believe the clarity the glasses give me. I truly can't believe what I've been missing. I kept them on at work all day and wore them to drive home. I'm also wearing them now watching television and typing this message. I can see what the doctor said about the possibility of having to remove my glasses to see small print clearly as I can see the difference. He told me that at about 43 I'd need progressives which is in about a year.


Maria Et  15 May 2017, 00:26

Can someone please explain my boyfriend's prescription to me?

left eye is +5.75-3.25x165

right eye is +5.50-4.25x170

His glasses magnify his eyes, I was always thought + was for reading but he wears his glasses or contacts for everything.

I want to understand his eyes more...


NNVisitor 14 May 2017, 21:06

How can anyone cheat on the eye exam? Don't they use different letter arrangements so people can't relay the information to others in order to prevent cheating?

I've never dealt with getting a drivers licence as I don't have an interest in driving even though I could if I wanted to and obtained a drivers license. It's not because of my vision as my corrected vision is usually 20/25 to 20/20 with my contact lenses. I just don't want to drive in crowded city traffic or even on the highway dealing with trucks etc.


Maxim 14 May 2017, 14:08

to Jenny:

It's a bit like in the swimming pool before you are in the water: you don't want to enter, because you think, the water is cold. When you're in the water, you are moving, and you don't feel the cold, you just feel fine.

I am convinced, that these glasses will solve your problems .....

"I've definitely had to deal with headaches especially when working on the computer for any length of time. I also haven't been able to read street signs or see faces of faraway people for quite some time especially at night".

.... and you're going to love them.

You will have such a rich vision with these glasses!

Make sure, that you buy nice frames, or buy a second or a third pair from Zenni's, just not only for a good vision, but for looking nice as well.


Jenny 14 May 2017, 13:25

I've definitely had to deal with headaches especially when working on the computer for any length of time. I also haven't been able to read street signs or see faces of faraway people for quite some time especially at night. At least the last two times I've renewed my DL I've cheated on the eye exam part so I'm sure legally I need them to drive. I'm not so sure I'm ready to wear glasses all the time, but I won't know until I get them. I guess I'll just have to wait until they come in a week or so.


 14 May 2017, 11:52

to Jenny:

I can confirm, what Soundmanpt wrote to you - this will be the most different part of the adaptation to your glasses.

"Don't be surprised if the floor seems tilted or slanted and you may feel dizzy and sick to your stomach and have a headache as well".

This can last (my own experience many years ago) for up to four weeks - but these situations did not last for more than two or three minutes. I left the eyes bare eyed for this small moment and everything was o.k. Later, the brain had obviously learnt about the new situation of the 'modified optical input' (my own word creation).

But in the long run, it's worth everything wearing glasses instead seeing affected by the vision defect.

And, last not least, a lens for astigmatism is like holydays for the eye. With astigmatism uncorrected, the eye is always searching for a focus point, stressing the eye muscles and cannot find it (that is one of the causes of fatigue, strain, and headaches). With the correction lens, the eye is stable. This is very similar to an autofocus camera and the lens drive - this remark, if you are a photograpy fan.

Recently my daughter in law had this experience, she always suffered from headaches, and she had a -1.00 correction for astigmatism on one eye only, and she is so happy now!

Best wishes, and courage!


Tom1 14 May 2017, 06:56

The guy who answered before me is 100% right.

However, let me add a point. Did you have troubles so far due to your vision? Were there things you could not do since you didn't see well enough? Did astigmatism precluded something you wanted to do and cannot do since you do not have perfect vision?

If this is the case you life will certainly improve with glasses on since everything will be much more clear.

On the other hand, if this is not the case and you hardly realised you needed glasses, I'm wondering if it is really needed for you to get 20/20 vision and become accustomed to glasses. In fact, if and when you will start using glasses full time, it will be much more difficult for you to do without, as you are acually doing now...

You are the only one who can decide how much wearing your glasses (in fact glasses are not a cure for any vision defect, they are only an aid to improve your performance when you are wearing them).


Soundmanpt 13 May 2017, 20:00

Jenny

My first question to you is to ask if you often get headaches maybe around mid day? If you don't I am quite surprised considering you prescription. Quite often people start getting headaches when they only have a need for -.75 astigmatism correction and you're at -1.75. That is why the doctor and saleslady / optician was surprised that you aren't already wearing glasses. I think that you are likely to have a real problem with adjusting to your glasses once you get them. Unlike being near or farsighted where if your nearsighted you would simply wear glasses when you wanted to see something in the distance or if you were farsighted and only needed glasses for seeing close up such as for reading. But astigmatisms effects your eyesight at all distances. i'm almost positive that when you first put your glasses on you're going swear that they aren't the right prescription. Don't be surprised if the floor seems tilted or slanted and you may feel dizzy and sick to your stomach and have a headache as well. That is the reason the doctor is suggesting doing things where you won't be moving around too much such as sitting down watching TV with your glasses on. You're eyes are sure to go through an adjusting period. But once your eyes do adjust I think you will not be taking your glasses off except to clean them and to shower and at bedtime. Yes you're going to be wearing your glasses full time.


Jenny 13 May 2017, 15:19

Had my first eye exam yesterday in 20+ years at Foreyes. Doc and saleswoman were both shocked I hadn't been wearing glasses and said I would see a significant difference when my glasses arrived. My script was PL/-1.75 100 PL/-1.75 65. Don't know much about prescriptions but the doctor said I have a good amount of astigmatism and probably had it for years. I'm 42 currently btw. He also tested my near vision and even though I could see the smallest line only with help, he decided I could just take my glasses off if necessary for another year. He didn't really give me a recommendation of how often to wear the glasses, but he did say to get used to them while watching tv and doing things around the house because there will be an adjustment period.


Benn 13 May 2017, 07:30

Thanks a lot.


 13 May 2017, 06:20

to Benn:

Your confirming question to my answer ....

... the value stated in rx would be the placement in the circle . So does it mean that the max would be 12?

I think, you got it right.

The method is as followa:

The optician or eye practioner sits in front of person to wear these glasses:

Start with the right eye / right lens of the patient

Right eye: sph XY / cyl -3.00 at 0 degrees means axis horizontal fro the right to the left / looks like 3 o'clock.

R.E.: sph XY / cyl -3.00 at 15 degrees would be at 2.30 on the clock

axis at 30 degrees would correspond to 2.00 o'clock.

axis at 45 degrees (halfway, just diagonal) would be at 1.30 on the clock, etc.,

until we reach at 12.00 (noon/midnight) with the 90 degree axle.

But 12 / 90 is just a position, not a maximum!

The axle can turn outwards, reaching for example 105 degrees, this corresponds to 11.00 on the clock, and it closes with 179 degrees at 9.01 approximately.

The denominations of the lower part of the circle (from 181 to 360 - corresponding 8.59 to 6.01 on the clock are not used).

I personally have a prescription for astigmatism.

The minus cylinder is nearly vertical (up-down)

Right eye: sph xxxx / cyl - 2.00 A 100 degrees

Left eye: sph xxxx / cyl - 1.00 A 95 degrees


Maxim 12 May 2017, 16:48

Unfortunately not in English -

https://www.youtube.com/watch?v=WB7hzW1Zg4g#t=72.703695

Two screens are used: corner right down the lens, center effect of turning the lens.

Demo of astigmatism starts at 2 minutes 50 seconds.


Benn 12 May 2017, 07:41

Wow...thanks. It is very complicated. I appreciate your help.

So if I am getting it at all, the value stated in rx would be the placement in the circle . So does it mean that the max would be 12?


Maxim 12 May 2017, 00:15

This object

00000

00000

00000

00000

1. seen through a prescription lens

+/- 0 (plano, no myopia, no hyperopia) but cyl - 3.00 at 0 / 180 degrees:

00000

00000

2. the same object, seen through sph 0 / cyl - 3.00 at

90 degrees:

00

00

00

00

00

3. same object, now combined correction for myopia and astigmatism, e.g.

sph - 3.00 / cyl - 3.00 at 0 / 180 degrees:

oo

4 same object, now combined for myopia and astigmatism,

e.g. sph - 3.00 / cyl - 3.00 at 90 degrees:

0

0

5./6. You can also look through lenses with combined correction for hypermetropia and astigmatism (plus lenses), but this cannot be presented as simple her, plus lenses are causing a kind of blurr.

An example for a combined plus prescription:

Right eye: sph + 4.00 / cyl - 2.00 90 degrees

Left eye: sph + 3.75 / cyl - 1.50 100 degrees


Maxim 11 May 2017, 16:14

I could also describe the system by a clock.

Your lens with an astigmatism correction of - 3.00 cyl with no myopia or hyperopia correction could be mounted

at 0 degrees = 3 o'clock or 9 o'clock

at 90 degrees = 6 o'clock or 12 o'clock -

other examples could be:

Right eye at 45 degrees 1:30 and

left eye at 135 degrees = 10:30

and so forth.

The surface of the lens with a cylinder (=astigmatic) correction hasn't got the shape of a perfect ball, but the shape of an egg, of a mango, of an american football instead.

When you put those lenses in light beams (bicycle lamp, pocket lamp, sun shining etc.) the plus lenses concentrate the light in two lines, and not in a punctual structure. The minus lenses for myopia don't spread the light evenly, but more in one direction than into the other direction.


Maxim 11 May 2017, 16:02

PS: Have you been a good scholar in mathematics and/or in geography?

These degrees refer to the 360 degrees of a full circle (in two dimensions a cylinder, or a ball), similar to the East-/West and North-/South degrees describing a position on the earth.


Maxim 11 May 2017, 15:52

No answer so far to Benn's question? I'll try it.

1) astigmatism comes together with myopia, with hyperopia or with +/+ 0.00 (plano).

2) astigmatism correction is defined from the left to the right, then as = degrees or 180 degrees

OR from top to bottom (vertical) as 90 degrees,

OR as values between those (diagonals etc.).

3) if you look through a lens with no correction for myopia or hyperopia, but with a -3.00 cyl correction for astigmatism at 0 degrees / 180 degrees, a person like Arnold Schwarzenegger with shrink, and would look like a little fat man like Laurel from Stan and Laurel.

If you look throught the sam lens, but turned by 90 degrees (now -3.00 cyl at 90 degrees) Arnold wil look same size, however much slimmer and thinner, like Stan now.

You can make a simple check, if a given pair of glasses has a correction for astigmatism:

When you turn the glasses, looking through the lens, and a person (or a door, a cupboard, a window etc. - everything) changes change theier shape from fat to thin, then the lens provides correction for astigmatism. When they don't change their shape / their form, then we have a simple myopia or hyperopia correction (or no correction at all) without corretion for astigmatism.


Benn 10 May 2017, 11:00

Okay I need help. I understand plus and memos numbers. I can see a -3.00 lens looks like or a plus 3.00. But what does a minos three in astigmatism look like.

Sorry to be so dumb.


Cactus Jack 12 Mar 2017, 19:46

Wondering,

I think you may find this helpful, particularly the part about Astigmatism.HOW TO STUDY FOR AN EYE EXAM

An eye exam is not like an exam that you might take in school and there is really no way to study for it. However, you can prepare for it and learn about your role in the exam. The best eye exams are a team effort between you and the Examiner. Part of the preparation is to learn what to expect, particularly if this is your first eye exam.

One important thing you need to keep in mind is that the Examiner has no way to experience what you are seeing. He/she has to depend on your answers to questions.

There are two parts to an eye exam. The first part is the Objective part. This part consists of:

1. Taking a Visual History where you describe your vision and the kinds of problems you are having.

2. Checking the internal pressure in your eyes for symptoms of Glaucoma. This is one of the very few parts of an eye exam that is even mildly uncomfortable and the discomfort only lasts for a few seconds. There are two basic ways to do the pressure test.

A. Using a special instrument to lightly touch your Cornea. Not to worry here. Before doing this type of test a drop of mild anesthetic will make sure you don’t even feel it.

B. There is a new type instrument that uses a puff of air directed against your cornea. No anesthetic is required, but the puff will startle you. The puff of air is harmless and there are huge benefits. Detecting Glaucoma early, before it can do damage can save your eyesight.

3. The examiner will also get a preliminary estimate of your refractive error by using an Auto-Refractor or manually by using a small hand held instrument called an Ophthalmoscope or Retinoscope.

The Auto-Refractor is a relatively new instrument that was developed in conjunction with NASA to check Astronauts vision in space. You look into the machine with each eye individually where you will see a scene or a pattern. The machine will adjust its internal lenses to focus the image you see on your retina. The Auto-Refractor only takes a few seconds for each eye and it then prints out your estimated prescription.

Some Examiners prefer to use manual methods that have been used for many years. Using an Ophthalmoscope or Retinoscope and a Trial Lens set or a Phoropter (a fancy machine with a built in lens set), the Examiner will look into your eyes and select the lenses that allow him to see your retina, most clearly.

The object of this part of the exam is to get a starting place for the Subjective part of the exam where you have to describe what you see.

Typically the Subjective part of the exam starts with the Right Eye shutter open and the Left Eye shutter closed.

Step 1 is typically determining the cylinder and axis of any Astigmatism correction you need. This is actually the hardest part of the exam because you will be asked to judge relative blurriness of two images rather than the sharpness of an image.

You will be shown a line of text and a supplemental lens will be rotated into place. This lens is a cylinder lens that is mounted on a 45 degree pivot and can be flopped back an forth to bracket a trial axis or orientation of the long axis of the cylinder lens. The thing that is confusing about this test is that the straight lines (strokes) of the letters will alternate in clarity as the lens is flipped back and forth depending on their direction. I suggest concentrating on an “O” if possible. Depending on your answers, the examiner will adjust the axis knob unit the image you see is equally blurry with the supplemental lens 45 degrees each side of the selected axis.

At this point the Examiner will probably swing the supplemental lens out of the way and may change the cylinder power while asking you which lens in clearer.

For your first exam, you may be uncomfortable asking the Examiner to let you fine tune the Cylinder Axis, but I have found that most will appreciate your wanting to actively participate. The way that works is that he will place your hand on the Axis control knob. This time, you move it back and forth a few degrees looking for the sharpest image. It is a bit like “Fine Tuning” an old Analog TV set or moving the tuning knob on an analog AM radio for the best signal.

The next step is determining the Sphere correction. This is an easy part of the exam because all you have to do is pick the sharpest image, but there is a tricky part. Your auto-focus mechanism will try to help, if it gets a chance. The Examiner has a couple of ways to minimize the action of your ciliary muscles and crystalline lenses.

The Examiner can, in effect, sneak up on your Sphere prescription or he can use drops to Dilate your eyes. Lets talk about sneaking up on your prescription first. There are actually 4 lenses in your eye’s lens system. All of them are PLUS lenses and the total power is about +56 to +60 diopters. The only variable focus lens is the crystalline lens whose PLUS power is controlled by your ciliary muscles. For distance, your Crystalline lens is fully relaxed and has somewhere around +15 diopters. When you focus to read, your Ciliary Muscles squeeze the Crystalline lens to increase its PLUS power by the amount necessary to focus which depends on the distance to the object.

This will take a little thought to get your mind around, but if you are nearsighted, your lens system has too much PLUS for the distance from the lens system to your retina and you need MINUS lenses to neutralize some of that excess PLUS power. You ONLY have the ability to increase the PLUS power of your lens system. You have NO ability to reduce the PLUS power of your Crystalline lenses more that fully relaxed.

To try to keep your Ciliary Muscles and Crystalline lenses from getting in the act, the examiner will start with NOT ENOUGH MINUS or TOO MUCH PLUS (same thing) and gradually increase the MINUS one or two steps at a time, while reducing the size of the line you are asked to read. He will not tell you what power lens or what line you are looking at. Eventually, he will reach the 20/20 line and a lens power that lets you read it with no mistakes.

He will then follow the same procedure with your Left Eye.

When he has completed both eyes, he will open the shutters and you may see two images. This part of the test is to check your muscle balance using some prisms. He will probably ask you to tell him when the two images are aligned horizontally and then vertically. While the images are separated, you have an important check to make. Compare the sharpness of the two images. If they are not equally sharp, be sure and tell the Examiner which image is clearer. If there is a difference, he will likely reduce the sharpness of the clearest image until they match. The important thing at this point is that they match. That lack of sharpness will be corrected in the next phase with both eyes working together.

Next he will fuse the images so both eyes are working together and repeat the Sphere procedure by gradually increasing the MINUS or decreasing the PLUS until you see the smallest line of letters very clearly.

That pretty much completes the exam except for checking your near vision with a small chart about 14 to 16 inches from you.

Many people, who wear glasses, actually look forward to eye exams. Once you have become accustomed to having very good vision, you will probably find anything less, unacceptable. Many times, after the exam, it will be suggested that you get another exam some time in the future. Note that I used the word “suggested”. it is NOT a Command. If your detect a problem or if your vision seems uncomfortable, please don’t wait until the “suggested” date to seek an appointment to get your vision checked.

C.


Wondering 12 Mar 2017, 11:16

Thanks Soundmanpt, I think I get it! So for example is an axis of 10 an equivalent of 170? Just looked at an astigmatism axis chart. So the numbers I have have only moved approx 20 degrees . My short sightedness started at -0.50 in both eyes with no astigmatism, several years later it's-1.25 and -1.00


Soundmanpt 12 Mar 2017, 10:22

Wondering

Prescribing for someone with astigmatism is the most difficult part of an eye exam for any optometrist. First of all let me assure you that even though the numbers may seem quite different to you they actually aren't. You mentioned that you're mildly shortsighted so you have probably noticed that since you first started wearing glasses you SPH has either not changed or changed very little but any change was always an increase. That is very normal for everyone. But CYL is seems to increase or decrease from one exam to the next but generally it usually doesn't change too much aver time which as you can see yours hasn't. The axis first of all is not a power value so being a 2 or 180 doesn't mean your eyesight has changed. That number determines the positioning of the lens for each eye and goes from "0" to 180. Now try and think of these numbers going around a circle much like looking at a clock with 180 numbers going around it. So then you have had an axis of 180 if you go backwards isn't that far from 20. It's not 160 numbers away but rather only 20 number away. I hope this helps.


Wondering 12 Mar 2017, 09:55

Hi all, ok so got a bit bored and sorting through paperwork, I have kept copies of my eye test prescriptions.

I've noticed that every time I go to the opticians I get different results for cylinder and axis, sometimes none at all, why is this? Are my changes drastic or just minor and stable? I'm mildly short sighted

My most recent test early this March shows

R-0.25 x165 L-0.50 x180

Previous tests over the years:just Cly and axis shown:

R 0 L-0.25x20

R-0.50x170 L-0.50x10

R-0.25x180 L-0.50x5

R-0 L-0.50x10

R-0.25x160 L-0.50x15

R-0 L-0.50x180

R-0 L-0.25x15

R 0 L 0


Maxim 27 Feb 2017, 17:06

Clearly "yes".

Your prescription is a minor prescription, and it would optimize your vision.

But the vision is clearly sufficient for driving, as far as the resolution is sufficient.

You could compare this to the 'pixels' in a digital camera. You obviously have eyes with sufficient 'pixels, and also with sharpness below the optimum, the acuity is still sufficent.

However, you should buy cheap glasses with this prescription, you might like the optimization of your vision.

Astigmatism means, that the surface of your lens is not a perfect ball surface, and every moment the muscles are trying to force the surface in the perfet shape. With this prescription, these muscles could relax. That's the effect.

I have not enough time in the moment to give a more thorough explanation, but that is the idea.

Best wishes!


punktlos 27 Feb 2017, 14:33

I've had the eye exam today and don't really know what to make of it.

First I did the automatic test again, after which the optometrist told me that the results speak for wearing glasses permanently because of -1 diopter of asigmatism and -1.5 at night vision. (I didn't know that was a thing, different diopter values for day and night...)

Then they did what you called the "subjective part" of the exam. And to be honest I didn't notice the difference in most of the lenses she put into the test frame. I could read the bottom line with any constellation, it wasn't very small anyway.

I ended up with sph +0.5 cyl -1.0 7 for my right eye and sph +0.25 cyl -0.5 174 for my left eye. However, comparing my vision with the test frame and without it I didn't see a real difference. I told my optometrist so, and she said that probably my better eye compensates a bit and that glasses didn't make sense as long as I don't experience head aches.

I'm a bit puzzled now. Can I drive at night like this?


punktlos 21 Feb 2017, 10:20

I'm living in the EU and study humanities. I'll let you know "numbers" when I get the exam next Monday.


Cactus Jack 21 Feb 2017, 08:53

punktlos.

I suspect, if you get an eye exam, the prescription will not be very strong. Higher level school work typically involves a very high visual workload, but if you are fortunate enough to have good vision, your eyes and brain can easily deal with it without needing anything, glasses for example, to help. With a few exceptions, such as driving, wearing vision correction is optional. There is no such thing as Vision Police and you don't need the permission from anyone else to wear or not wear vision correction no matter what your vision is.

The human body is amazingly adaptable to its environment. Even if you have perfect vision and excellent health, an eye exam is a good idea. The eyes are windows into the body. There are a number of "silent" health conditions that are first detected on an eye exam. Most of these conditions are easily managed if caught early, but can cause serious problems later in life. Diabetes, High Blood Pressure and Glaucoma are good examples.

It could be that the Optician just wants to sell some glasses. Unfortunately, that happens, but not very often. If it happens, it typically happens in large optical chain stores where there is considerable pressure to "upsell" nice-to-have additions such as Anti-Reflective Coatings, ultra thin lenses or designer frames. Independent Eye Care Professionals (ECPs) rarely do that. In most countries, if you pay for an eye exam, it is required that you be given your prescription. It is NOT necessary that you order glasses from the examiner. You can order glasses from any optical dispenser you wish.

I really need numbers to offer suggestions, but I can offer one suggestion now. If you get an eye exam and you get glasses, it is often best to wear them full time for about 2 weeks before making a decision about when to wear them. That gives your brain time to become accustomed to having good images to work with.

May I ask where you live and your field of study?

C.


punktlos 21 Feb 2017, 04:13

That piece about eye exams was an interesting read, thank you. I'm not sure I comprehended every detail, though. Physics has never been my strong point back in school.

I'm not quite sure, however, if I'm really in for a pleasant surprise. If I understood you correctly, once my brain gets accustomed to this new kind of vision, it will no longer work as hard for me as it used to, leaving me with bad vision.

You know, I don't really see a big advantage in this, as I'm not experiencing tired eyes or headaches (I don't even know how they feel, fortunately never had them in my life...).

I'm 20 and a student, by the way.


Cactus Jack 20 Feb 2017, 15:24

punktlos,

Not really very high, but I think you are in for a pleasant surprise.

Vision actually occurs in the brain. Your eyes are merely biological cameras. Depending on age, most people can correct a little farsightedness (Hyperopia), internally, using their auto-focus system.

However, Astigmatism has to be corrected externally. Astigmatism is usually caused by uneven curvature of the front surface of the Cornea and it affects vision at all distances. Your eyes have been delivering distorted images to your brain.

I mentioned that vision actually occurs in the brain and the brain has amazing ability to correct some distorted images, IF it knows what something is supposed to look like. The snag is that it takes effort and energy. The brain even has the ability to generate images WITHOUT input from your eyes. Ever had a dream?

If you get glasses, which correct the images optically, it will take a few days until your brain learns that it no longer has to work so hard.

Think of glasses as simply tools to make it easier for you to see well. Really, they aren't any different than other tools you use every day.

You might consider reading "How to Study for an Eye Exam". I think I posted it recently on the Vision thread. If you can 't find it, let me know and I will repost it.

May I ask your age and occupation?

C.


punktlos 20 Feb 2017, 11:31

Hey there!

Today I spontaneously decided to take a computer eye test at my local optician. I didn't (and don't) feel like I had bad vision, but figured it wouldn't hurt to check anyway as I didn't have them tested since I had a little accident with a sled back when I was 8. I'm going off at a tangent here...

I was shown a red balloon getting blurry and before i knew what was happening they told me to come back later the week for a proper eye exam. Apparently I'm a little bit far-sighted in both eyes and have an astigmatism of roughly minus one diopter at 2 respectively 16 degrees (I don't remember the exact diopter values).

I was a little bit shocked, because like I mentioned, I'm not under the impression of being far-sighted and somehow all these numbers sound rather severe to me. Can someone unconfuse me on that matter? Are these strong values?


Cactus Jack 04 Feb 2017, 14:05

Fred,

Texas is a pretty decent place to live. I heard recently that about 1000 people per month are moving here from California and the Northeastern States. The cost of living here is reasonable and the business climate is excellent. The weather in the summer isn't all that great, but that is why we have Air Conditioning. Houston has a reputation of being HOT and HUMID from May to November. Someone asked me what the temperature was in the summer. I told them 72 degrees F. with brief episodes of hot and humid as I go from my Air Conditioned home to my Air Conditioned car and the Air Conditioned stores and offices. I don't think Houston would exist without Air Conditioning.

Many of the new residents have a saying "I wasn't fortunate enough to be born in Texas, but I got here as quick as I could.". Maybe next time, you can stay longer.

Feel free to contact me privately at cactusjack1928@hotmail.com, if you wish.

C.


Fred 04 Feb 2017, 13:23

Cactus Jack, ha! don't worry.. i get that! i've been to texas once, but never left the airport it was just a connection, unfortunately. but i actually really love texas and all of the american south! i read a lot of southern american literature, i told you i'm a literature guy before i think haha and southern literature is actually my favorite, and i always read in the original language so i'm somewhat familiar with the dialect too! i hope you have a nice week!


Cactus Jack 04 Feb 2017, 12:06

Fred,

The English question was pretty dumb. If you spent 6 months here, you probably have no problems with English. However, we don't think they speak English in New York and they are pretty sure we do not speak English in Texas.

C.


Cactus Jack 04 Feb 2017, 11:51

Fred,

I live in Houston, Texas. I look forward to hearing the results of trying the reading glasses over your regular glasses. I will be unavailable most of next week.

BTW, your English is excellent. Do you speak English or are you using a translator?

C.


Fred 04 Feb 2017, 09:28

Cactus Jack, that's so cool to know! i've heard about são josé dos campos but i've never been there. i've been to são paulo though for like three days. i live in rio grande do sul it's the southernmost state, i don't know if you know it. i don't blame you for not learning portuguese it's a very tricky language! sometimes people who are trying to learn ask me things and i can't help them because so much of it is just unwritten rules that you just have to remember. where do you live in the US? i was there last year for six months, in new york city with my brother. and i've visited multiple times in other occasions too! ..Thank you so much for your advice i'll try it this week! i don't really experience double vision though, i mean with the astigmatism a little bit but when i'm wearing glasses that gets corrected. Thank you for your time!


Cactus Jack 04 Feb 2017, 08:18

Fred,

Many years ago, in 1975, I spent a week in San Jose dos Campos at the Embraer plant, teaching the technicians how to install and trouble shoot autopilots in the Piper aircraft they were assembling under license. I didn't learn much Portuguese because the technicians wanted to practice their English.

I also have an acquaintances who lives in Sao Paulo. He has tried to teach me some Portuguese, but it may be hopeless at my age.

This may be a little hard to believe, but I am wondering if you are having some Presbyopia combined with some dry eye problems. The idea that Presbyopia is not a problem until your 40s is a myth. It can actually happen at any age and our modern world just makes the problem worse. I would like to suggest an inexpensive test. Get or borrow some Over-the-Counter reading glasses in the +1.50 to +2.00 range and try wearing them over your regular glasses when you are doing some close work. Try to blink more often and use some artificial tears occasionally. You may not need all of the above, but it would be a quick test to see if we are on the right track. Don't try the reading glasses by themselves because you need the Cylinder correction in your regular glasses.

You also could have a convergence issue, your eyes have to converge when you do close work or you would see double. Have you ever experienced double vision or trouble keeping images fused, particularly when tired?

Many ECPs, particularly older ones, have trouble understanding that our visual environment has changed and Computers, Smartphones and Tablets all involve close focusing. Young people, with Hyperopia are particularly vulnerable to Presbyopia problems at a much earlier age. The reading visual load required in most University programs, just makes the situation worse. I was moderately nearsighted when I was in University and had to get bifocals when I was 20 because of headaches.

Please let me know if any of this helps.

C.


Fred 04 Feb 2017, 05:21

Cactus Jack, the discomfort is worse when reading and studying! for close work. for just being outside and not doing any near work there's nearly no discomfort at all. i thought i had mentioned this im sorry! and i live in brazil actually! south of brazil close to uruguay, so i'm in the summertime right now! and no worries by the way there's no rush for you to reply i'll wait! :-) thank you..


Cactus Jack 03 Feb 2017, 20:44

Fred,

He increased your PLUS Sphere and reduced your Cylinder.

I don't think I have asked you when the discomfort occurs. When you are reading or studying, when you are outside, etc. We need some clues.

Also, I don't think I have asked you where you live. Tat can affect my suggestions.

I will be out of town for most of next week, but should be around over the weekend.

C.


Fred 03 Feb 2017, 17:38

Cactus Jack, i want your guidance on this.. haha! so, remember i was having problems with my eyeglasses and they were making my eyes hurt? i tried the eye drops that you suggested but they were of no help, unfortunately. so i went to an eye doctor again a new one and told him all about it, all the issues with my eyeglasses that i had been experiencing. i did an eye exam and he even dilated my pupils to see if everything was all right. turns out he got the same prescription again and told me my eyeglasses weren't made wrong or anything. so what he did was basically cut my prescription strength in half.. the astigmatism strength i mean.

and he gave me this:

OS +1.00 -0.75 cil x 175 OD: +1.00 -0.75 cil x 5.

my first prescription was this:

OS +0.50 -1.25 cyl x 175 OD +0.50 -1.50 cyl x 175

he told me this should help and if it doesn't for me to come back and that it really is hard for some people to adjust to my amount of astigmatism at first.. now here's the thing, i dont know if i should do these new lenses now, since my old ones weren't wrong. what do you say? will they really help me do you think? or should i just stay with mine until i eventually adjust 100%. thank you!!! sorry for the long post. also sorry for bothering you so much!


Fred 18 Dec 2016, 16:55

thank you cactus jack! always helpful... i will try the artificial tears With lubricant and if that doesn't help i'll let you know! also yes im a student i remember the last time we talked you told me your story about the cookies and i never replied back but just letting you know i thought it was pretty funny haha thank you!


Cactus Jack 18 Dec 2016, 11:44

Fred,

I don't thing it is astigmatism related, but don't rule that out, completely. You may have some Latent Hyperopia that is resolving and you need a bit more + Sphere. Before considering another eye exam, consider the possibility of dry eye problems. I don't remember if you ever said where you live, but it is pretty common in winter with low humidity. I suggest trying some Artificial Tears WITH lubricant. There are several brands. I look for those with Carboxymethylcellulose or (as strange as it seems) Polyvinyl Alcohol. Whenever I think of Alcohol, I think of a possible stinging sensation. That does not happen with Artificial Tears. They are pH balanced and typically the drops are soothing, particularly if they are approximately body temperature. If that helps or doesn't help, please let me know. I have a couple of other suggestions.

One other thing, you said you were a student and do a lot of reading. Very often, you don't blink enough when reading. You might try consciously blinking more when you read, to spread the tears you have around more in addition to the Artificial Tears.

C.


Fred 17 Dec 2016, 09:54

hey! i've been here before and you all seem very knowledgeable so here i am again! i have a new question.. so, my glasses are causing my eyes to burn lately like a burning sensation. sometimes they only show up when i first put them on, and sometimes they stay and i have to stop using them and rub my eyes and that often helps. i dont know if maybe my astigmatism isn't regulated anymore and i need a new prescription? even though i got mine only 6 months ago... i've been wearing them a lot and they've been fine only lately they've been causing this burning sensation and i dont know what it could be. anyone have any ideas? thank you! i didnt think glassses could make your eyes burn so im curious! also heres my prescription again in case anyone needs to know OS +0.50 -1.25 cyl x 175 OD +0.50 -1.50 cyl x 175. thank you!


Likelenses 28 Nov 2016, 20:33

Adam

See an eye doctor.

You will definitely get a prescription for glasses.

Do not be surprised if you get correction for both eyes.

A number of years ago a girl friend at the time,was having similar symptoms as yours.She thought that her left eye was bad only,but came away from the doctors office with a prescription slightly stronger for her right eye.

As I recall the Rx was, Rt eye +.25 -.75 cyl.

Lt.eye -.25 -.50 cyl.

After just a few days she was wearing the glasses full time,or she would get headaches.

Over the next few years the lenses got progressively stronger.When I last saw her she was around -2.00 sphere in both eyes,and the cyl was about-2.50 for the Rt.,and -1.50 for the Lt.

I could always tell when she needed stronger lenses,as she would squint badly with the glasses on.

She often complained that she thought that her Rt. eye had been perfect,and that the doctor set her up for ruining the vision in it by giving her a lense for it.


Adam 28 Nov 2016, 10:28

Dear Everybody,

According to online eye tests and my symptoms, I have astigmatism in my right eye (my left is perfect). It has never been a big problem because I could saw the eye chart with my right eye except the last row. On the other hand, I saw all the numbers and letters a bit blurred. It means that my distance vision is not that bad but the difference is easily recognizable compared to my left eye.

However, my near vision in my right eye is quite bad. It means I have to be close to the monitor to avoid squinting but it is never clear enough even if I'm very close. If I try to read the monitor with my right eye from normal distance, I am squinting very hard to read.

What do you think, should I visit the eye doctor to get glasses or contacts for my right eye or is it okay now? If I use both eyes, I have no problem but once I read that it is better to correct the worse eye. Thank you in advance!


Cactus Jack 22 Nov 2016, 21:21

Astigmaphile,

No chutzpah required. Just find an ECP that uses a regular Phoropter or Trial Lens Frame. Both have knobs for adjusting the Axis angle. Typically, you don't have to move it very far to find the sharpest image. If I am going to a new ECP, I always ask if he/she will let me fine tune the Axis at the appropriate point in the exam. I have never had a refusal. In fact, it tends to be an ice breaker and changes the atmosphere of the exam from an ECP to Dumb Patient, to one of Senior and Junior Colleagues working together to get the best prescription possible.

The relaxed, non-defensive attitude helps make the exam a pleasant memorable one for the Examiner. When I go back to the ECP, they often remember me and the exam become like a conversation between colleagues.

As you may recall, I have had some problems with Strabismus and getting the prescription right takes a bit longer. The ECP I like best, even has his receptionist schedule a double exam period for my appointments. He knows of my interest in vision and optics and I think he enjoys spending the extra time and taking the extra care.

Remember, the worst that can happen is that the ECP says NO! Of course, if that happens, that will be the last they see of me or my money. Once you try it, you will never want to do it any other way.

C.


astigmaphile 22 Nov 2016, 15:31

Cactus Jack,

I have never seen the newest model of phoropter for real but have seen them on YouTube. The whole thuing is controlled from a keypad or keyboard. There are no knobs on them. I wish that I had the chutzpah to ask an eye doctor to let me get my hand on the axis knob.


Cactus Jack 22 Nov 2016, 07:32

lisa,

That type of Phoropter is a recent innovation. It is controlled by the panel you described. I had an exam a few years ago with one of those machines in a room that was very small, equipped with a special screen that optically simulated a much longer room. I was not happy with the resulting prescription and never went back to that ECP for an exam. Many ECPs use an exam room with a mirror and projector or display that gives a true target distance of 20 ft or 6 meters. That works OK, but a very few ECPs actually have exam rooms arranged with the Snellen Chart display 20 ft or 6 meters from where the patient sits. That seems to be the best of all. The problem with that is that office real estate is expensive.

Unfortunately, I am not very familiar with the machine you described. I don't think it is possible for you to fine tune the Axis the way I described.

I can't imagine that any really good ECP would object to your asking questions and asking for an explanation of what you should be looking for. There is absolutely no way for the Examiner to see what you are seeing. They have to depend on how you answer their questions. An Eye Exam is NOT an inquisition. It actually should be a very pleasant experience that leads to sharp, comfortable vision.

Remember, that in most instances, YOU are paying the Examiner for their knowledge and skills. A good exam is actually a team effort. Sometimes, you have to shop around for an ECP that you feel comfortable working with. It is regrettable that some ECPs are not good communicators, just as some MDs are not good communicators. Don't be afraid to ask for explanations. You don't know their language, it is their responsibility to speak yours.

I hope this helps. May I as where you live?

C.


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