Ataxia

My partner (66 years of age) has a low-grade lesion(tumor) on the parietal area of his brain.(Found only when MRI's came into being) He has been told that he could have had it since birth.
The very mild seizures(loss of feeling down the left side for 30 -60 seconds) resulting from this have been controlled for at least, the last 15 years by Tegretol (2x400 mg daily) From about 1995 or 1996 he has also been taking Topamax (2x25 gms.)
For the last 3 or 4 years he has been experiencing increasing difficulty in mobility with his legs. He says that some days his feet feel like lead weights. Some days the problem is worse than others.
From about January this year he has also had irregular occurrences of speech slurring. He has had numerous tests, showing that his arteries are 'the cleanest' in Melbourne and that his problem with slurred speech is not stroke-related.
His current specialist has discovered that he lacks the intrinsic factor related to producing B12 and has had B12 injections for this. However, no change has been noticed in his ataxia. Perhaps the two are unrelated. The specialist has also uncovered a mild, chronic case of motor-neuropathy, cause unknown.
Can you possibly shed any light on this seemingly far-reaching problem, please?
My question is 'Could the prolonged use of the mix of Topamax and Tegretol cause such debilating ataxia and slurred speech?'

[Roger Gould, M.D.]

Topomax is a possible cause of the speech slurring, and it is not a dose related factor.  Neither of these medications is known to cause the kind of peripheral nerve dysfunction you describe, but both can cause paraesthesias, which may be what you are describing.  I am not an expert in this area, this question really belongs to the neurologist on this site, so I suggest you redirect your question there.

[StupidMe]

Ataxia and speech problem can be caused by a combination of Topamax and Tegretol but usually happen much earlier and in higher doses. You can check their blood levels. Brain tumor growth can cause a lot of problems but can be monitored by MRI.