other than being clean and relatively oil free.
If your conduction tests are worse, well, you know something is causing progression. Please read this article:
http://www.aafp.org/afp/980215ap/poncelet.html
Just click on to the 'blue'. While it is an older article, it does outline the differences to a degree between small fiber and large fiber deteriorations; it also explains in part how a good neuro should be testing you for diagnosis. I have both fiber issues and they are noticable, and all I can say is, that as long as I can 'feel' ANYTHING I am not going to complain [too much].
Seizure meds really don't affect the NCV processes because they only measure the speed of the 'stimulus' to the brain and back. Meds only interrupt the pain signals in the brain- tho I am beginning to doubt their long term effectiveness.
As for actually finding out what is really going on?, when you sign those multiple piles of papers 'releasing' info to any who require them, be sure TO REQUEST A COPY OF THE SUMMARY REPORTS for yourself. You can get them in most states, tho some states [or docs] are sticky/picky about how they interpret privacy acts & can make it harder. If you can't get them from the primary source, demand them from your doctors! You may have to pay [my GP charges $10. for copies from their office], but my neuro doesn't charge so go figger.
MRI's even more of them for back issues sounds like a good idea from all you have written about your problems. While the MRI's don't show 'nerves' per se, they can zero in on back/spinal/hip areas where those nerves might be compressed or the like.
As for getting confused about what the doc says and remember later? Well, tho not legal per se, you could always take a little dictation recorder in with you so you can replay it all later. I don't now, but I did a time or two. I now simply carry a notepad w/questions on it and two pens [as one always never works]. Hope this helps. - j