MRI for crossed eyes, worried mom

Hello,

Over the past few months we have noticed an increasing inward drifting eye in my 4 year old daughter. We brought it up during her yearly checkup recently, and they referred us to an ophthalmologist. He confirmed that she has strabismus, but her vision was otherwise perfect, which he found unusual. She has been prescribled correcting glasses, which she now wears, but we were also referred to the children's hospital for an MRI scan.
Now my husband (who took her to the ophthalmologist) did say that the docter said though rare, the strabismus could be caused by a tumor so they wanted to be on the safe side. He said he'd seen it once or twice in his career, and there was a 99 % chance everything would be just fine. However, I can't help but worry anyway, once the word tumor is used. I don't mean to be over concearned, but I can't help but feeling concerned anyway. Especially since we expected nothing more than her needing glasses or a patch or something.
What sort of tumor could cause strabismus? And is there really not much to worry about? The MRI isn't untill in 3 weeks. I'm nervous about that as well, since we have been fortunate to not have needed any, and I have not really a clue what will happen, when we get results, and so on.
I'm hoping to get some more insight as to what I can expect.
Thanks!

[Flavius G Pernoud III, MD]

I wouldn't worry about a tumor especially if the eyes have straightened with glasses. I don't know of any tumor that would allow that to happen.