Sorting out the reason for a ghost image - I need ideas.

[PlasV]

I'm trying to figure out the optical physics behind a ghost image that no-one has been able to explain to me to my satisfaction yet.

I have had cataract surgery with single focus spherical lenses in both eyes. In the right eye, I have an ERM that's been there for a while. Prior to the IOL placement, I had distortion, and some size discrepancies from the ERM, but no ghosting. Now, after the IOL implant, I have a very annoying ghost image that appears just above the center of fixation, and at times, under certain lighting conditions, it's quite distinct. There is also some vertical smearing between the two images.

At the time of the surgery, they also did a limbal relaxing insision for astigmatism correction.

The practice that did the cataract surgery says the IOL placement looks correct, and can't explain it, and my retinal specialist says it may be from the ERM, but is not sure. Both MDs say it is some sort of refractive error - hmmm - that's obvious to me.

Now, here is the interesting part. I can TOTALLY fix the ghost image with either of 2 simple manuevers.

First, I can tilt my head back, but maintain the point of fixation straight ahead. At some threshold point, the ghost disappears. Two things come to mind from this manuever. I may be seeing a pinhole effect, or knife edge refraction effect from the lower lid, OR I may be possibly blocking light from entering the lower part of the pupil by the lid. I can also recreate this by holding a small piece of paper in front of the eye with the top edge just under fixation.

I also can eliminate the ghost (just found this out tonight) by applying a very small amount of pressure on the upper right corner of the eyeball, thru the lid.

[PlasV]

I have an inconclusive, but probable followup answer. Working with my optometrist, we are able to correct a fair amount of the smeared ghost image with an astigmatism correcting lens. There is some residual ghosting that disappears with my blocking technique. The cornea seems to be ok, but he might have me do some followup with a cornea specialist. However, we both think the residual ghosting is likely from the ERM, as I demonstrated the way I was able to block a portion of the image hitting the retina. Based on what I saw on the OCT scan from the retinal specialist, it makes plausible sense to me. The IOL placement looks good, and no shifting has been observed.

I believe the next move will be to finally have a vitrectomy. If you see other posts by me on the other forums, you will note it is a long standing ERM, so I'm a little less optimistic about the outcome.

I have not gotten lenses. I think I will wait until after the vitrectomy, and make do with readers for close work with the good eye, and live with the ghost for now.

The real puzzler still to me is the very large day to day, and sometimes hour to hour, variability of the ghosting. At times, it virtually disappears for a short time. I told the optometrist that perhaps it's the piece of the ERM directly over the foveal pit that's just "flapping in the breeze" as the vitreous changes. I am on some NSAID drops for retinal thickening, so perhaps they are also affecting the position of the ERM somewhat.

life's an adventure . . . . . . .

[PlasV]

Dr. Vosoghi,

Thank you for your comments.

Since my earlier posts, I found a very interesting article linking corneal topographic changes to extraocular muscle surgery. Now, that is really interesting to me, as I do have some discomfort with eye movement from time to time which feels like the muscles are having a hard time, especially around the upper part of the orbit - in fact, it sometimes hurts a bit with movement. That links into perhaps a couple of things - a side effect from the recent cataract surgery, with the numbing of the muscles, or perhaps an intermittent  nerve/muscular problem that I have that goes from my neck, up around the side of the head and to the brow. That's another variable which come and goes. I think I need to see if there is a correlation of the visual aberrations and the muscle feelings. The fact that my vision was MUCH better last night, until I laid down on the floor flat and stretched/popped those back and neck muscles and joints, and that just MAY be a valuable clue to follow up on.

I don't have any pilocarpine handy, but I'm sure my MD would let me try that. I also have glaucoma, and am on several different drops, including Alphagan-P (new after the glaucoma surgery to keep pressures down post-op) which for me does have some pupil constriction, especially in low light.

I'll also try to learn more about irregular astigmatism. I'm guessing that the hard contact lens keeps the corneal surface more or less fixed, thus eliminating a variable? Does the corneal surface change with irregular astigmatism?

As you can see, there are so many variables to look at - that's why I'm guinea-pigging myself first to get a clearer idea of what's going on before presenting myself back at any of the doctor's offices. I'd like to have some evidence to present to avoid wasting time.

I'm leaning more towards a corneal explanation the further I go with this, but as you say, there are other variables to eliminate. I'm still a bit suspicious that the IOL may be shifting slightly as well.

Also, I'm a technician (in a different area) and I just cannot give up without figuring something out :-) - it's in my nature!

[Houman Vosoghi, MD]

Sounds like you have done a great job figuring out all the possibilities yourself!  I am impressed.  You can narrow down which is the correct cause by doing a few different maneuvers in clinic with the help of your ophthalmologist.  First, I would get fitted for a temporary hard contact lens to see if the problem is irregular astigmatism.  If that makes it go away you have your answer.  If not, next step is to use pilocarpine drops for a couple of days to induce a pinhole type effect and reduce glare from the lens (this would tell you whether its the IOL that's causing the shadow - if it makes it go away).  If both those steps fail, you are likely looking at the ERM as the cause.  This isn't a guaranteed 100% way of making the right diagnosis but it has worked for me for a few patients.  Good luck and please keep us posted if you figure it out.

HV

[PlasV]

A followup - this is nuts . . . .

Last night, several hours after posting this, I was watching TV, and noticed the ghost image was entirely gone! I couldn't believe it. I could see faces clearly pn the screen in that eye, and could read the text perfectly, so my VA improved in addition to the ghost image going away!

Shortly after, I got down on the floor to do some back stretches. While I was lying there, I was watching the TV, and saw the image "slide" back out of focus to the ghost image and poor VA, and it was back to where it was. Of course, if I go into the ophthalmologist office today, they will see nothing changed, and will think I'm crazy. I sure don't understand what's going on.

[PlasV]

Continued due to character limit constraints:

So I'm left with trying to figure this out, as it is SO annoying.

My possible explanations are:

1 - It is from the ERM, and the new lens makes it more obvious than before with the cloudy lens.

2 - The IOL is slightly misaligned, and causing the issue.

3 - The limbal relaxing incision has actually created some astigmatism.

4 - The cornea has some problem, and perhaps all the meds have been on have done something to the surface.

I might add that dry eye preps don't help - perhaps a tiny bit - and that the IOL has not provided clear vision at distance, and I can improve that with a lens. with the ERM in the equation, that might have effected final outcome, and the the power calculations for the IOL are essentially correct. I also might add that the outcome of the lens implant in the left eye is pretty darn good at this point.

Any ideas?

I would love to get another unbiased opinion from someone not familiar with me, but I'm not sure who to consult - perhaps an adult strabismus specialist who is used to diagnosing double vision problems.