Polyneuropathy means many nerves involved in the peripheral nervous system (PNS) which is outside the brain and spinal cord. Here is a site that might be interesting for you.

http://www.nlm.nih.gov/medlineplus/e...cle/000777.htm

Perhaps you should ask your doctor to explain it all to you in layman's terms. Just a thought.

The myelin is the fatty sheath that coats the axons. Due to environmental or genetic reasons it can start to break down.