Sorry, the private message didn't seem to send to you..so either you have 2 of the same one or none! So I'll paste what I said on here...
My brother recently had decopression surgery ( end of September this year) and it sounds like he has the exact same problem as you. He has been told he has a leak and has large pockets of what they have said is fluid in the back of his head. He is in a lot of pain and is sick constantly, can't keep any food down or sit up. He has been admitted this morning for the second time this week but we haven't heard anything yet as the hospital he's in doesn't have a neurology department.
I was just wondering if you did have any further surgery or if it did sort itself out? Or if there's any other information that you think might help?