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Read this if you don't see sharp stars...Map-dot-fingerprint dystrophy

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#26 Eddgie

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Posted 15 January 2017 - 07:35 PM

Ok, I am so sorry that I said anything about optometrist.

 

This draws attention away from the main point which is that there is a condition that can contribute to the inability to focus a star to a point and that this condition has a name and that it has a treatment.

 

That was the purpose of my post.   People that have the symptom should ask whoever they go to if this condition is present in their eye and if so, then they should discuss the potential impact on their vision and whether they should see a medical professional to assess a possible treatment.

 

Clearly one person here besides myself has mentioned it, and has been diagnosed for it. 

 

Others with the symptom may find that they have it too.. I don't care who they go to.  The primary point of my post is to introduce the condition to a population of people that would perhaps be more likely to see the effects than the most people in the general population.

 

I apologize and beg forgiveness is I have disparaged the optometrist community or any member of said community.


Edited by Eddgie, 15 January 2017 - 07:42 PM.


#27 IanJ

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Posted 17 October 2019 - 09:19 AM

Hi,

 

During a search I found this thread, I do have map-dot-fingerprint dystrophy as well. My condition was found after a small chip of wood scratched the eye and this damage made the condition worse. I can confirm when the top layer of skin detaches from the eye the pain is excruciating and lasts for days. The eye starts to repair the surface but each time you blink it rips the new skin off. Last time this happed the hospital fitted an eye bandage contact lens and this protected the surface while it repaired. Eye drops and thick eye ointment at night have so far helped.

 

I have now retired (the eye problem was a factor) and have set up an observatory at the end of the garden with a Evolution 9.25 scope. I accept at some time I will have to go down the electronic route of observing but I want to visually observe while I can. I am a bit disappointed with the view with the 1.25 eyepieces and think the eye condition is a large factor in the problem. If I purchase 2" eyepieces does this spread the view over a larger area of the eye so reducing the impact of the small patches of roughness on the eyeball?

 

So 2" or a camera?

 

Thanks

 

Ian

 

 

 

 



#28 TomTTuttle

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Posted 17 October 2019 - 10:10 AM

Wow, I had never heard of this... something else to worry about. Just what I needed.undecided.gif  (tfpic)

 

Serious though, next eye exam I will be asking. Thanks for sharing.



#29 Eddgie

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Posted 17 October 2019 - 11:17 AM

Hi,

 

During a search I found this thread, I do have map-dot-fingerprint dystrophy as well. My condition was found after a small chip of wood scratched the eye and this damage made the condition worse. I can confirm when the top layer of skin detaches from the eye the pain is excruciating and lasts for days. The eye starts to repair the surface but each time you blink it rips the new skin off. Last time this happed the hospital fitted an eye bandage contact lens and this protected the surface while it repaired. Eye drops and thick eye ointment at night have so far helped.

 

I have now retired (the eye problem was a factor) and have set up an observatory at the end of the garden with a Evolution 9.25 scope. I accept at some time I will have to go down the electronic route of observing but I want to visually observe while I can. I am a bit disappointed with the view with the 1.25 eyepieces and think the eye condition is a large factor in the problem. If I purchase 2" eyepieces does this spread the view over a larger area of the eye so reducing the impact of the small patches of roughness on the eyeball?

 

So 2" or a camera?

 

Thanks

 

Ian

The exit pupil being used will be more of a factor than the size of the eyepiece, but since many times, 2" eyepieces are purchased for lower power work, then yes, the effect could be worse.

 

It behaves just like regular astigmatism in that some people can never get a small enough exit pupil to eliminate the effects, but others can get by without glasses when using higher power eyepieces.

 

The primary characteristic in my own case was that it did not look at all like classic astigmatism.  Stars had irregular and curved spikes radiating out from them.

 

In the last two years, I have had a total of four PRKs on my right eye using a wavefront laser to try to correct for the hills in my eye, which I take to be a residual product of the map dot fingerprint dystrophy and after a total of six different medical procedures on my right eye, I am now able to see a star as a round spurious disk even at larger exit pupils. 

 

I did not ask them to try to correct my distance vision after the first three PRKs because they kept overshooting. One time I would be overcorrected, the next time I would be undercorrected.   Two surgeries were done by one doctor, and two were done by a second doctor.  On the last try, I instructed them to ignore the distance correction and concentrate on the hills on my cornea.  I would rather have to wear glasses and be assured of excellent vision than to have good distance correction but abberated blurs when using a telescope.  At my age, I need readers anyway, so wearing glasses full time is not a problem for me.  I can also wear a contact for sports if I like.

 

I hydrate my eyes with preservative drops several times a day.   I do have a tiny amount of dystrophy in my left eye, but it has actually improved since I started a heavy hydration routine. 

 

I am now seeing 20-20 out of both eyes.


Edited by Eddgie, 17 October 2019 - 11:28 AM.


#30 Eddgie

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Posted 17 October 2019 - 11:24 AM

And both doctors said they had never seen anything like the negative results I had with PRK.  The laser was overshooting by 1.5 dipoters to 2 diopters and when done, the hill, which I take to be a residual of the dystrophy would move but it was persistent. 

 

The first doctor actually referred me to the second doctor because the second had the most advanced wavefront laser in the state, and even their stuff produced the same result on the first try (overshoot, and still had the hill, which produced a second lens so that I had two images) so the doctor huddled with his entire team and after a lot of discussion, we decided on the approach to reduce the power for the overall correction adjustment (knowing that it might leave me still having to wear glasses for distance correction) and focus all energies on burning off the hill.  

 

I call it a success.  I am seeing the best I have in maybe 15 years.  I have to wear glasses, (no astigmatism correction, just distance) but I am seeing great now. 

 

It is a beautiful thing to see perfectly split colored double star again and have it look like it did 15 years ago. 


Edited by Eddgie, 17 October 2019 - 11:53 AM.


#31 Eddgie

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Posted 17 October 2019 - 11:41 AM

Another thing I have learned is that a laser spot makes a great substitute for an in focus star.

 

After every surgery, I would project a laser spot across the room and observe the spot with and without the glasses or contacts with the post surgery prescription.

 

I could actually see the change in the pattern as the eye healed (about four months for me after each surgery for stabilization.

 

I got so good at it that when I was not wearing the glasses, I could tell how many diopters out of focus my eye was just by looking at the size of the blur.

 

Before the last surgery, the pattern looked like a "V", with small arcs between the sides of the V and an arc at the widest part of the V that looked like the arc was cut from the edge of the outer ring of a star test. 

 

 

Five months after the last surgery, I now see what looks much more like a standard diffraction pattern.  It is not perfect, but it is mostly round and shows the classic Fresnel pattern.

 

When I wear my prescription glasses, the laser spot is a hard, sharp point, with no spikes or irregularities; just a perfect spot.  The difference between the before and after is enormous. 

 

Maybe I will ask the Dr to provide the interferometer readings.

 

Strehl was .29 before the surgery (corrected for sphere). I don't know what it is now, but I would say that it is very high (corrected for sphere) because again, I see a perfect spurious disk on stars and a hard, sharp point with a projected laser (with glasses, no astigmatism correction). 


Edited by Eddgie, 17 October 2019 - 11:42 AM.


#32 John Fitzgerald

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Posted 17 October 2019 - 12:18 PM

An optometrist  diagnosed me with MDF many years ago.  I had been a contact lens wearer since about age 30.  The contacts corrected it completely, so it went unnoticed.  I don't wear them all the time now, don't need them for driving, or everyday tasks.  I usually only wear the contacts while observing.



#33 Steve C.

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Posted 17 October 2019 - 05:20 PM

I do wonder how many problems (or virtues) have been reported with various telescopes that were due in large part to differences in eyes. 


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#34 SeaBee1

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Posted 18 October 2019 - 10:10 AM

And it might be good to bookmark this thread and if you don't mind sharing, report back on any positive tests, so that we build more awareness in the community.

Again, I have even told people that spikes on stars was caused by astigmatism and clearly that was gross ignorance of this condition.

 

If we get a few more people that report getting this diagnosis, it will help others with understanding the condition and help them be more aware of it.

 

It is thought to be hereditary, and it normally progresses as we age.   

 

 

Eddgie, my eye doctor is actually an MD, and he has never mentioned this condition. He has always treated me for astigmatism, and I always thought spikey stars were normal. I have never complanined to him of the spikes... but I will now!

 

Thank you Sir for posting this!

 

CB

 

I had forgotten about this thread until it popped again yesterday. I had my annual appt earlier this year and I actually did mention this condition to my Doctor... he was surprised that I even knew of the condition and asked how I learned of it. I mentioned CN and this discussion. He took a closer look at my eyes and confirmed I have a mild case of it and not in my direct line of vision. He informed me that my issue really is my astigmatism, and that he would not recommend anything radical to correct my mild MDFD. I am thankful (I think...) for this.

 

Clear skies!

 

CB



#35 IanJ

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Posted 18 October 2019 - 12:32 PM

Thanks for the replies, I like the idea of a contact lens as it might help smooth out the surface and improve things.

 

Ian




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