I had an incident when I had a shunt tap, and fluid removed, etc. The shunt was adjusted from 130-150. And checked by xray. A month later I had all the signs of too much pressure, however on shunt series, it showed 160 rather than 150. Soooo, I had it turned down to 130, and started having symptoms again. Now I'm at 140 and a happier camper. Symptoms were about the same as with too much pressure.
All my CT's show mild hydro, and have for a couple years. However, it was high pressure when I had the shunt done. Think it's okay for now.
I hadn't realized the symptoms of high and low pressure could be so similar. I do know that when I would lie down for any length of time, the headache would ease some. All I have learned about hydro and shunts is from reading, and especially this site. Thank you for it.