Who did the MRI/MRA, was it a neurologist? What did they diagnose you with and what did they attribute your symptoms to? You say you wear a bite guard so I gather your being treated for TMJ. Have you spoken to that doctor/dentist about these symptoms? There is a separate thread for Trigmeninal neuralgia and your post will get more exposure there. Look at the bottom of the main page and you'll see the thread there. There are also "stickies" at the top of the thread which have a lot of good info and links to sites with reliable information that you should familiarize yourself with.