gogo

My 16 years old dog had a seizure 2.5 months ago. Doctor said that was either a infection, or a neoplasia in brain. She took medicines (Dalacyn, cortison and lasyx) and she had some small seizures during these 10 days but she began to eat and react normally. When the antibiosis finish she had the same symptoms again (no reaction to food cycling all the time). She began another (antibiosis), baytrill and Flagyl, and it looks a little bit better every day. She is free of seizures from 12/1/08, but she is always walking in circles (always to the right) and doesn't react normally. She looks like doesn't understand when we talk to her (sometimes she turns her head only to the right). A week ago she stretched her head up for about 2 minutes. She doesn't sleep a lot during the night. We have to feed her because she can not find her bowl.
I'm going to do MRI to her but I am wondering if someone has any idea of all these signs. Thanks in advance