Patients 21 years of age and younger, with Strata valve CSF shunts, who are being evaluated by the All Children's Hospital (ACH) neurosurgical service as part of standard of care, will be eligible for participation during the three-year enrollment period. Each time an eligible patient has contact with the neurosurgical service their valve will be checked for possible inadvertent reprogramming in the outpatient facilities, emergency department, and inpatient setting. Patients will only have their valves checked as part of this study once during each encounter. Only patients who were evaluated by the neurosurgical service and returned to their normal environment more than seven days prior to their current encounter will be eligible to have their valves rechecked as part of this study.