Strata Programmable CSF Shunt Valve Study

The treatment of hydrocephalus is the most time consuming, and arguably the most important role of the pediatric neurosurgical service at most children's' hospitals. Despite many technological advances, cerebral spinal fluid (CSF) shunting procedures remain the mainstay of hydrocephalus treatment. While often lifesaving, CSF shunting procedures are associated with high complication rates and account for a disproportionate share of health care expenditures and morbidity. Programmable CSF shunt valves, through which CSF flow and pressure can be adjusted by quick and painless transcutaneous reprogramming, have been implanted for more than 15 years in the developed world. Reprogramming these valves relies on rotational magnetic forces, which are applied by neurosurgeons and neurosurgical advanced practice providers. Inadvertent reprogramming (IR) can occur when patients with these valves are exposed to magnetic fields in the environment, which may lead to serious symptoms that may require urgent reprogramming and/or surgery. The concurrent proliferation of magnetically sensitive programmable CSF shunt valves and household items that generate substantial magnetic fields has caused concern among patients, parents and providers about the potential consequences of inadvertent valve reprogramming. This growing concern led the FDA to issue a warning to individuals with programmable valves in 2014, which deemed the programmable valves safe for use but vulnerable to IR when household devices such as tablets or cell phones are placed within 2 inches of the valve. The FDA recommended further study, stating that no systematic evaluation had been performed regarding the prevalence of accidental valve adjustments. By evaluating each of the patients with magnetically susceptible CSF shunt valves, during each of the routine points of contact with the service, investigators aim to define the prevalence of inadvertent shunt reprogramming, to correlate with the presence and absence of symptoms and radiographic changes, and to evaluate the risk of inadvertent shunt reprogramming based on exposure to common environmental items.

Investigators intend to evaluate all patients 21 years old and younger with magnetically susceptible CSF shunts, specifically those with Strata (Medtronic, Dublin) valves implanted. All evaluations will be performed during routine patient care in the hospital, the emergency department and in the outpatient facilities. Valve settings will be checked transcutaneously in the standard manner, before and after any MRI studies. Evaluating IR and making correlations between exposure to MRI or environmental magnets and symptoms and radiographic changes (when available) will require the patient or family to complete a brief questionnaire. It will then require the study team and delegated providers to check the valve setting before and after MRI, and to gather clinical information from the medical record and from the current clinical evaluation. Each patient's initial enrollment will require the acquisition of an informed consent, which will cover all future evaluations of IR during the three year study period for that patient. However, every time a patient enrolled in the study encounters the neurosurgical service, all study steps will be performed, including the valve check before and after MRI, the participant's completion of the questionnaire, and the research staff's completion of the data sheets.