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Dr-Trace, Board Certified Ophthalmologist
Category: Eye
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Experience:  Board Certified in General Ophthalmology
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[Q: For Dr. Trace]1. Is astigmatism best measured when

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[Q: For Dr. Trace]

1. Is astigmatism best measured when not dilated and pupil has its normal aperture? Or does dilation have no effect?

2. Besides binocular diplopia, my other major issue seems to be astigmatism. Let me give you the following input, and please respond with your thoughts:
(the following is observed regardless of dilated or non-dilated)

Binocular + fused = blurry
Monocular L or R = blurry
Pinhole L or R = crisp
Contacts L and/or R= less blurry

For example, when I say blurry, the text on this screen is very difficult to read and the text is a very light gray color. When I pinhole, it's crisp and I realize the text is actually black. The astigmatism correction I have (cyl -0.75 ax 130/30) helps a little, but not nearly as much as pinhole. (I heard that pinhole won't even get someone to 20/20, so I would suspect I should be able to get at least close to pinhole clarity via corrective lenses?)

(I've had topography done and the surface was fairly regular. I tried hard lenses just in case, but they didn't seem to make a difference.)
Hi, I am a Moderator for this topic. I sent your requested Professional a message to follow up with you here, when they are back online. If I can help further, please let me know. Thank you for your continued patience.
Customer: replied 4 years ago.
(for reference, my monitor is 52" HD and more than 3 ft. away)
when I pinhole, lettering not only changes from light grey to black, but also from fine-point to bold.
OK - Reading your symptoms points to improperly corrected refractive error. Pinholing is an example of what your vision would look like with best corrected visual acuity. So you need to be very tightly refracted and given not only the correct myopic or hyperopic correction but also the correct astigmatism.

What the pinhole does is focus the image on the retina regardless of the distance away. All light and observed objects come through a tiny line of sight so the image is directed onto the retina without any accommodation or focus. We pinhole patients all the time to get an idea of their best possible corrected acuity with glasses. Then we refract until we match that best acuity.

Rarely astigmatic abberation can cause the pinhole acuity to be better than refracted visual acuity but this is very rare and not possible after lasik.

The only other thing that may be a problem is epithelial ingrowth beneath the flap of the lasik causing abberation which is eliminated by pinholing. That is all I can think of. If there is debris under the lasik flap, the corneal topography will be normal, hard lenses wouldn't help and all other parameters would fit.
Customer: replied 4 years ago.
So an astigmatism measurement will be equally accurate diliated or not dilated?

Ok, so this is what I understand:

1. I should fist be checked for epithelial ingrowth/debris beneath the flap. How would that be done?

2. If that is ruled out, then I should be correctable up to the clearity I experience via pinhole? Since I'm far from that now, my prescription must be substantially off. If that's the case, I don't know what to do because every Dr. I've seen either says "you don't have a prescription", or "I can't figure out what your prescription is, lets try this one". I'm exhausted from trying new Drs. but also exhausted from not being able to see.

I wonder if it's possible my astigmatism is affecting my accommodation, or even the diplopia directly?
Astigmatism is not affected by dilation. Any doctor that looks at you with a slit lamp exam should be able to see epithelial ingrowth or other corneal abnormality.

If this is ruled out, you should be refractable to 20/20 with or without atropine on board. The other alternative is to get a corneal topography (I am sure you had this before lasik) to look at the possibility of irregular astigmatism.

Here is what I suggest. See if you can make an appointment with one of the big city ophthalmology centers. NY, Philadelphia, Baltimore, Cleveland, Cincinnati, Miami, Las Angeles, etc. Let me know where you are and I will give you a suggestion.

I would have you seen by the cornea department and get the refraction done. If they can't get you to 20/20 and see and measure no problems with the cornea, then I'd be surprised. The fact that you pinhole so well means it is possible to get you to that vision with some work, we just need to find someone willing to take the time to do it.
Customer: replied 4 years ago.
I'm excited to hear of the possiblitiy I can get to 20/20, that would be such an awesome change to my life.

I've had slit lamp exam more times than I can count, and although they noticed I had prior lasik, none have remarked about any ingrowth, so I should be ok there.

(One Dr. thought she saw the beginnings of cataracts, but pinholing wouldn't make that type of interference go away right? So I'm assuming even if I did have the beginnings of cataracts, it's not what's causing this pronounced difference between pinhole and not pinholed.)

Correct, like I mentioned I did have a recent corneal topography. She didn't think it was irregular enough to be an issue, but we tried hard contacts in the office just in case. (I'll try to get a copy of the topography for my records)

So what I"m understanding is a wet refraction is no longer necessary because we've already pretty much ruled out accommodative spasm with this Atropine experiment?

I like your idea of a refraction to get me to 20/20, I just don't know if I can take another letdown of a Dr. concluding the exam with shrugged shoulders. To answer you, I'm located in Charlotte, NC and have seen 8 eye Drs here, I also saw one up at Duke's eye center, and also one when I was up at Mayo Clinic in MN. Duke said my eyes were fine so I must be imagining it. (which doesn't seem to make since because even the small prescription I have now makes a very noticable difference.) The Mayo Dr. said he didn't even want to try an exam because all the tests he usually does had already been done previously by my Drs in Charlotte.

Maybe I'll be lucky enough that you know somone within driving distance of me. Otherwise, maybe we can try to figure this out as best we can so I'm prepared enough when I go for another exam that I'll be able to walk out with 20/20 lenses. I know it's harder when I'm not there in person, but we could look at this as a challenge.

If it helps, common experience for me have been...
"The digital machine says you're -4 something, but the phoropter says you're +.5, so I don't know what to make of it. Try these BI prisms" ... or...
"I can't get you even close to 20/20 (using phoropter), but this seems to help a little bit, so try these contacts for a couple weeks."

If you have any quesitons, let me know.
OK the digital machine saying you are -4.00 is consistent with accommodative spasm. You are accommodating when they measure you digitally. Now that you are on atropine, you need to be refracted fully dilated to tell what your true prescription is. Then I would have that prescription given to you in very good quality lenses and have you walk around with that for a while just at distance to see if you get used to it. Then I would let the atropine wear off and see how you do accommodating through the distance glasses. Remember, if there is some + power in the distance lenses, this will help you at near and you won't accommodate as much even up close. That is what I would try first.

There is a possibility that this could be cataract and you can pinhole through cataract if they are eccentric (off center). I have had one or two cases like this over the years. You also talked about autoimmune disease and if you were put on steroids at any time during your illness, these drugs are notorious for causing cataract in young people.

I don't know anyone personally in your area but I would recommend Duke. I have met a few of the oculoplastic people from there and they are excellent.

It might be worth a trip to a cornea person there again.

Let me know.

Dr. T
Dr-Trace, Board Certified Ophthalmologist
Category: Eye
Satisfied Customers: 26
Experience: Board Certified in General Ophthalmology
Dr-Trace and 2 other Eye Specialists are ready to help you
Customer: replied 4 years ago.
Unfortunatly she mentioned the early-stage cataracts were dead center. But the good news is, if I can pinhole clear, they must not be causing much of an issue for me.

I will reconsider seeing someone at Duke, even though I was disapointed about getting no help when I went before. (should I ask for a cornea/refraction specialist?) Otherwise I will go up to NY. (any in particular?)
Customer: replied 4 years ago.
The one major question/hang-up I have before going in for another wet refraction... drops take away accommodation, which I understand is not normal to have, but it is reality. A prescription which ignores reality doesn't seem like a very useful prescription. e.g. I don't walk around with atropine every day, so even though it's my "true refraction", the prescription would not correct my actual real-life vision situation. Please give your thoughts.
The prescription does not ignore reality. It is your true distance prescription when your muscles are completely relaxed. Accommodation is normal to have. Overaccommodation or accommodative spasm is not normal to have.

With your true prescription at distance, you should see clear at distance. That is what you should wear and it should refract you to 20/20 at distance. Then you should use your now rested (and off atropine) accommodative muscles to bring the focus in from far to near in a normal fashion, not in spurts and spasms where it locks at near. That is how the eye works properly.

Before coming to NY I would recommend a cornea/anterior segment/refraction person at Duke. NY is in my opinion not as good as Philadelphia - where I could recommend Irving Raber MD at Wills Eye Hospital.
Customer: replied 4 years ago.
hum... maybe it will shed some light on the situation to explain that in my case the accommodation never moves in spurts or locks at near. I would only describe it as a tendancy to accommodate a bit more than appropriate, and this can be compensated for by straining... (which I guess somohow adds negative sphere and/or relaxes the accommodative system).

To illustrate, if I'm looking across the room and straining to obtain focus. Releasing the strain or putting on +1.25 readers both create the same magnatude of blur. So I'd guess that in my normal relaxed state I'm over accommodating by about +1.25.

The other interesting note... if you recall I mentioned I could get clear vision via pinhole, but I notice it still requires straining (just less) and if I release the strain, even pinhole is blurry. (e.g. text on this screen will still look more black than grey, but I can't make out any of the words.)

Maybe this new input points us to some other cause or possible solution??
No - it all fits with over accommodation. If you are looking across the room and over accommodating, putting on a +1.25 will blur you even more at distance. Putting on a -1.25 will clear the distance. With the spasm, your focal point is closer and the -1.25 sets the focal point back at distance. But it will not release the accommodative spasm. You should be clear at distance without any glass but your muscles are holding you as if you were near- sighted. This is why atropine is used to stop the muscular spasm. To keep your focal point set at distance.

Pin holing works better at distance than near but should still make images clearer either way. Picture a cone of light coming to a point on the retina. If the point of the cone misses the retina, it will be blurry. Pin holing eliminates the cone and only allows a straight line of light to come into the eye, thus any position on that straight line will focus on the retina. This is why pin holing works. If there are no factors blocking the media of the eye, pin holing will allow clear vision. If there is central cataract, corneal aberrations or retinal disturbance, pin holing will not work.

I think you should stop trying to strain to get images in focus. This may be why the spasm will not resolve. You are adding strain to an already over strained musculature. So you may not be getting better. Just let the atropine do it's job and wear cheater glasses for reading and computer. Give your accommodative complex a full rest like an injured muscle.
Customer: replied 4 years ago.
I feel like part of my communication did not get through.

... +1.25 readers when viewing distance do not blur me more, they blur me the same as relaxing my muscles. Hence I'm using them in this example only as a tool to estimate the amount of over accommodation I have, since readers and relaxing induce the same magnitude of blur when looking at a distant object.

.... I'm saying pin holing does not make images clear; neither near nor far. It only reduces the amount of straining required. So since pin holeing doesn't even get me clear, doesn't this mean refraction correction won't get me clear either?

It's looking like my eyes just really want to be at +1.25 so instead of trying to fight it, what about just wearing -1.25 contacts from now on? Is there any major problem with this solution?
You could try wearing -1.25 distance for a while but remember it may give you headaches because your spasm is not resolved. This may indicate however that you are no longer spasming -4.00, you are now just -1.25. That is a good thing.
Dr-Trace, Board Certified Ophthalmologist
Category: Eye
Satisfied Customers: 26
Experience: Board Certified in General Ophthalmology
Dr-Trace and 2 other Eye Specialists are ready to help you