Hello Jennifer @jseibert, I would like to add my welcome to Connect along with @ethanmcconkey and other members. I have read that a lot of the symptoms of arachnoid cysts depend on the cysts location. The following article mentions a little about that:

Arachnoid Cysts / Intracranial Cysts - Symptoms of an Arachnoid Cyst
-- http://weillcornellbrainandspine.org/condition/arachnoid-cysts-intracranial-cysts/symptoms-arachnoid-cyst

Have you thought about getting a second opinion? I’m not sure if it is an option for you but if it is, the Mayo Clinic is very good at diagnosing health issues that are difficult to diagnose. If you would like to seek help from Mayo Clinic, you can contact one of their appointment offices. The contact information for Minnesota, Arizona and Florida can be found here:

Mayo Clinic Contact Information: http://mayocl.in/1mtmR63