CRT ShuntCheckCRT ShuntCheck "Fit & Function" Study

Inclusion Criteria:

1. For the pediatric subjects, males or females, older than three and less than 20 years of age.
2. For the adult subjects, males or females, older than 35 years of age
3. Parent/guardian or alert subject (age 18 or over) capable of giving consent; subject less than 18 and of assent age must give assent to participate if appropriate and required by the institution. If the subjects are incapable of giving assent, then only parent/guardian consent is required.
4. Possess an unambiguously identifiable chronically indwelling ventricular shunt which crosses the clavicle.

Exclusion Criteria:

1. Inability or unwillingness of the parent/guardian or alert subject to give informed consent/assent (when appropriate) as required by the Institutional Review Board.
2. Study testing would interfere with emergent subject care or if the subject is scheduled to go the OR in short order.
3. Presence of an interfering open wound or edema over the shunt.