Hi Davrol and welcome to MedHelp.
You may want to hop over to the Chiari forum as there are members there that have Syringomyelia....it is a related condition to Chiari....
With Chiari the symptoms cycle...so they can come and go and change....I do not have a syrinx but I do not know if they can resolve on their own....
Do you know if your syrinx's are due to a congenital condition or was it acquired due to an injury?
From what I understand a syrinx can numb you to pain after a time...and left untreated can lead to perm nerve damage....only your Dr can tell you what is going on and how it is affecting you and your overall health.
Stop by the Chiari forum and talk with others that have a syrinx-
http://www.medhelp.org/forums/Chiari-Malformation/show/257