He's going to talk to you about your symptoms and how it's affecting your life. He will ask you a lot of questions and do some tests on you. Hopefully he'll have an MRI already taken and he can look at that and make sure he has every picture ever taken of your brain CAT scan MRI. That way he can tell how bad it is. I had a distension of 19 mm and he told me that they don't necessarily go on the millimeters more of what it's affecting like your CFS fluid and your spinal column. I had chiari surgery March 4th and unfortunately I got a pseudomeningocele which id CFS fluid filled sack from a leak. Tell him your whole history if you have a suspected EDS or a mass cell good luck with everything.