Sudden prescription change

brief history: I am a 25 year old female with a MCTD Dx because they don't really know what is wrong with me. I have had organ involvement in many areas (including my eye, in the form of scleritis), and most recently they noticed a "white matter hyperintensity" on my MRI, which is two years old and being repeated.

current issue: I have had three separate incidents where I developed double vision in my left eye (more like a ghost image below the primary image). The first time it happened, I got new glasses and everything was fine. Since then it has recurred, and gone away, twice. It seems to last just long enough for me to say, ok, well maybe I need new glasses AGAIN. (I was checked by two opthalmologists who said my eye was fine, and I cancelled a scheduled visual field test because my eye had improved and I thought it was unnecessary- oops). I notice it more in bright light and it starts up an hour or so after waking up. At night I don't notice it much because of the lighting I think. Reading on the computer seems to aggravate it SEVERELY. I saw the neurologist and he said I have superior oblique myochymia, because he looked in my eye and saw the muscle twitching. He prescribed me Lyrica, but so far (three days) nothing has changed. My question is this:
1. If this is simply a refractive issue, why on earth would my vision change and then go back? Does this mean I need two sets of glasses?
2. Could this be neurological? It is almost like my eye stops focusing, or goes haywire, after the stress of actions like reading?
Thanks so much!

[Forum-OD-MP]

1) yes, probably is a refractive issue.  but as you're finding out, sometimes these things are tougher than they initially seem.  if i had to guess i'd say you probably have lenticular astigmatism that is changing with either crystalline lens hydration/dehydration, and/or lenticular astigmatism that is changing with accommodative spasm/relaxation.  neither one of those is serious, but both of them are annoying to the patient.  changing lenticular astigmatism makes your astigmatism Rx change by the day/hour/min and has symptoms that you describe above.  we deal with this frequently in diabetics and patients taking diuretics, but also less frequently in non-diabetics.  

2) unlikely to be neurological

[watersulli]

Annoying doesn't begin to describe it! Thanks so much for your response and for doing this forum, it is much appreciated.