Has anyone had focal seizures centered within a brain lesion triggered by
lying down at night and/or aggrevated by exercise?

I have seizures involving intense tingling/burning sensation on right side
that is aggrevated by prolonged exercise or weight lifting and triggered by
lying down.  I was diagnosed with a stable lesion (possibly low grade
glioma) last July after having a gran mal while running.   My radiologist
and neurosurgeon can't see any fluid obstructions but my neurologist said
one might exist too small to detect on the MRI.

I'm on 500mg of Dilantin and 1000mg of Keppra to treat the seizures.  The
Keppra was recently added and gave me immediate relief but once I felt
better I increased my exercise level and now I'm having just as many
seizures as before.  I have the option of increasing the Keppra dose but am
concerned it could be like running on pain killers,  just masking a problem
that will get worse if left untreated.  Has anyone had experience with any
of this?