Withdrawn due to lack of enrollment.

The study hypothesis is that nurses and doctors can use a transcutaneously powered ultrasonic flow sensor to make repeatable and accurate hydrocephalic shunt flow measurements.

The study participants will align the flowmeter probe with a flow sensor hidden under a thick saline pad that simulates skin. A hidden pump will provide a known flow through the flow sensor as the participants make their measurements. Each participant will repeat these measurements over a period of weeks, and the data will tell whether operator skill influences flow measurement accuracy.

The study hypothesis is that a transcutaneously powered ultrasonic flow sensor for hydrocephalic shunts can be repeatedly and accurately read by medical personnel ranging from nurses to senior neurosurgeons.

The test will involve a prototype implantable hydrocephalic shunt flow sensor and readout electronics. The readout electronics use a pickup coil to transcutaneously operate the sensor once the coil is aligned with sensor's inductive coupling coils.

During the test, the shunt flow sensor will be hidden under a thick saline gel pad whose thickness approximates the skin thickness of an older pediatric patient. A syringe pump will provide a known flow rate through tubing connected to the sensor, but the study participants will not know the pump flow setting.

Three neurosurgeons and six floor nurses will perform this study. Each will use the Transonic flowmeter readout to align the pickup coils of the flowmeter with the hidden sensor to make flow measurements.

Each participant will repeat this measurement multiple times over non-consecutive days.

The recorded data will quantify measurement accuracy and repeatability between different operators, and will determine whether operator skill influences flow measurement accuracy.

Inclusion Criteria:

• neurosurgeon
• nurse

Exclusion Criteria:

• none

Three neurosurgeons and six nurses