Hello,
Thank you for your message. I am sorry to hear that your daughter is facing this issue, and that it is causing anxiety. This happened to my when my kids were 4, 7 and 10. In my understanding, hydrocephalus is a condition where spinal fluid can accumulate in the brain. It seems that this may sometimes not be an emergency. This was the initial advice which I received from a doctor, even after having an MRI. However, at that time, in addition to headaches, I also had really bad loss of ability to create memories and recall them. A second consultant who my wife immediately consulted recommended the keyhole surgery. The reason for this in my case was that a cyst filled with spinal fluid had formed right into the middle of my brain adjoining the hippocampus which is where memory formation occurs. Part of the diagnosis was a memory test called the Weschler, which involves repeating stories and numbers read out to you. My score was awful. So I had the operation, from which I recovered very quickly (although brain surgery is really scary beforehand). And a couple of days after, I was given the same memory test again and there was a very large improvement.
However, a complication came up. Over time, my memory problems re-appeared. It turned out that due to the damage caused by this cyst (in the middle of my brain) before it was removed, a condition called epileptic amnesia had developed. With this, epileptic fits occur only within the brain (not the body), and they are almost completely unconscious. This form of epilepsy doesn't affect driving or work, but I do have to permanently take epilepsy medication. As far as I know, this was not connected to the surgery itself but to the original cyst. Apparently, this form of epilepsy can be a complication of brain conditions like this. Fortunately, it is pretty manageable. As you mentioned that your daughter has some memory problems, if this doesn't disappear with the surgical treatment, what I described is one possibility. I am sure the doctors over there would be onto it.
If you would like to ask me any more questions, please do. My name is David and I live in Kyoto, Japan. Best wishes.