Clinical Research Directory

Inclusion Criteria: * 18 years old or older Adult men or women who possess a VP shunt placed for PTC; * Capable of providing valid signed informed consent, or has a legal guardian, health care agent, or surrogate decision maker (according to local statutes, and collectively referred to as "surrogates" in this protocol) capable of providing valid, signed informed consent; * Subjects will be asymptomatic visiting for routine care at 2-4 weeks post op Exclusion Criteria: * Presence of multiple shunts, or presence of more than one distal shunt catheter (regardless of function) crossing the clavicle ipsilateral to the shunt with suspected obstruction; * ShuntCheck test would interfere with standard patient care, or emergency shunt surgery that cannot be delayed is indicated; * Presence of an interfering open wound or edema over any portion of the VP shunt.