Cerebro-spinal fluid pressure

About a year or so ago, there was a research finding that I think is most interesting: cerebro-spinal fluid (CSF) pressure was found to be inversely related to IOP.  I can't imagine how one would change CSF pressure, and it might be a bad thing to do so.  But I have wondered if CSF pressure changes when an epidural or other spinal is administered pre-surgery, and if there is a change (ie. a drop in CSF pressure) and if so, if the lower CSF change would remain afterwards along with higher IOP?  I cannot find anything about CSF/IOP and administration of an epidural.