Clinical testing of CSF circulation.

Since shunting is almost a purely mechanical treatment that radically affects pressure-volume compensation, patients' cerebrospinal fluid hydrodynamics compensation should be examined before a shunt is implanted. Apart from an opening pressure and a resistance to cerebrospinal fluid outflow, pulse amplitude of intracranial pressure and the content of vasogenic waves are useful to gauge cerebrospinal fluid dynamics. Infusion studies, although invasive, may help with the decision about surgery. They also provide basic information for further management of shunted patients, when complications, such as shunt blockage, under- and over-drainage, arise.