I am not sure what internal monitoring is. I had a lumbar drain test, for which I was in the hospital for 4 days with a line hooked up to my back, like a constant lp, draining fluid off continuously. The nurses measured how much fluid was collected, once every hour. That info let the NS know if my production of spinal fluid was a constant rate or not and whether I was a goos candidate for a shunt. I was, and I had a lp shunt installed Nov. 1st last year.
Just for info, ICP is measured in both cm and mm of water, which makes things a bit confusing. I believe that your "300" is the same as our "30" reading. Anything over 25 is considered high, universally. An opening pressure between 20 and 25 is borderline (mine was always between 22 and 24). 7 to 10 is considered the low end of "normal."
Just found an interesting article on your topic:
[You must be registered and logged in to see this link.]Seems that there are test methods doing the same as the lumbar drain test but they put a hole in your head instead of your back.
Heidi has some info on this site too about monitoring:
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