went to my eye doctor for regular check-up (new glasses) and found out my optic nerve had some swelling the doctor immeately send me to a specialist and he had me do an MRI that same day, the MRI came back clean and now i just had a spinal tap, when i asked the doctor doing the spinal tap what my csf pressure was he said 31 i then asked what was normal and he said 18. I don't understand what this means can someone help me, i won't get actual results from my doctor for another 4 days, and the anxiety is killing me.