ShuntCheck Versus Radionuclide in Evaluating Shunt Function in Symptomatic NPH Patients

The primary objective is to demonstrate that the accuracy of SC and SC+MP for determining whether a VP shunt is patent or obstructed is statistically no different than the accuracy of the accepted standard test, radionuclide shunt patency study, when performed simultaneously.

A secondary objective is to determine SC and SC+MP results in the presence of possible partial obstruction, which defined as subjects with radionuclide clearance measured by T1/2 of 8 to 10 minutes.

A secondary objective is to compare ShuntCheck flow rate results to simultaneous radionuclide clearance as measured by T1/2. A secondary objective is to demonstrate that ShuntCheck flow rate results are statistically equivalent to simultaneous radionuclide clearance measured by T1/2

Inclusion criteria

• Adult men or women > 35 years of age;
• 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;
• Possess a shunt placed for AH;
• A radionuclide shunt patency study has been ordered because of suspected shunt obstruction
• Subject is willing and able to return to the treating physician for evaluation of the outcome of the shunt patency study

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;
• Subject is unwilling or unable to return to the treating physician for the SPS and ShuntCheck testing.