Short-term changes to cornea shape/prescription with new contacts?

I am a first-time contact lens wearer who has been wearing Acuvue 2
and Biomedics 55 lenses (trying to decide which works best for me) for
7 weeks now. I'm currently using the Biomedics, and the pair that I
have in my eyes at the moment has been giving me increasingly blurry
vision for the past week since I opened the package (my last pair of
the same kind did not do this). I don't *think* it's a moisture
problem because it's still blurry shortly after I flood my eyes with
Thera Tears drops. I usually take out and clean my lenses every
night, although I do sleep in them occasionally (once a week or so).
It almost feels as if my prescription has changed over the span of
about a week. My eyes are not generally irritated lately (although
they were for the first few weeks). My question is this: Is it
possible for the shape of the cornea to change over this short a
period of time (or at all) due to contact lens wear, leading to a
change in prescription? Any other ideas for why this is happening to
me? Should I try another kind/brand of lens?

Lothar

 

I had a similar problem, but moreso when I took the lenses out. Is your
vision any different from before you started the lenses after you remove
them? If so, then your cornea has changed shape. For me, this was temporary,
but took several days to go back to normal after not wearing the lenses at
all. What worked for me was switching to gas perm lenses because they had
better oxygen transfer to the cornea. I cannot wear the soft lenses for this
distortion reason.

Marianne