Telemetric Intracranial Pressure Recording via a Shunt System Integrated Sensor: A Safety and Feasibility Study

Background The dynamics of intracranial pressure (ICP) after shunt surgery in patients with normal pressure hydrocephalus (NPH) are poorly known. Temporarily implanted parenchymal pressure probes are reliable for accurate ICP monitoring; however, a disadvantage of this method is that the ICP probe has to be explanted after a period of time, requiring additional surgery. We present two patients with NPH with an integrated ICP measuring device in the shunt system that allows for long-term postoperative telemetric monitoring of ICP. Methods Two patients (one man, 66 years old, and one woman, 78 years old) with normal pressure hydrocephalus underwent shunt surgery using the Aesculap-Miethke Sensor Reservoir (Potsdam) as an ICP measuring device integrated in the shunt system. On the first postoperative day and during follow-up examination 3 months later, several measurements of ICP were performed using a handheld device to read the Sensor Reservoir data. Postural changes such as lying down, sitting, and standing with different head postures were assessed according to an experimental protocol in a randomized order during which the ICP was measured. Results There were clear ICP responses due to postural changes, in line with physiologically expected values. Because the highest sampling rate of the Aesculap-Miethke Sensor Reservoir is 1 Hz for continuous measurement of ICP, however, the collected data have to be considered an approximation for actual ICP dynamics. Conclusion The Aesculap-Miethke Sensor Reservoir is an easy-to-use tool to measure ICP changes reliably in patients with a shunt system. The sampling rate and handling of data acquisition may eventually be developed further.