Patent ID: 8894584

Claim:
An apparatus for determining cerebrospinal fluid (CSF) flow rate in an implanted CSF shunt, said apparatus comprising: a pad that is configured to be placed against the skin of a patient over the location of the CSF shunt, said pad comprising: a first plurality of temperature sensors that are configured to be aligned in a transverse direction with respect to said CSF shunt and wherein one of said first plurality of temperature sensors is configured to be aligned with the CSF shunt; and a second plurality of temperature sensors that are configured to be aligned in a transverse direction with respect to said CSF shunt, downstream of said first plurality of temperature sensors, and wherein one of said second plurality of temperature sensors is configured to be aligned with the CSF shunt; and a third plurality of temperature sensors associated with a temperature source that are configured to be positioned over the CSF shunt whenever said pad is placed against the skin; and a sensor processing device that is electrically coupled to said pad for receiving temperature data from each of said plurality of temperature sensors, said sensor processing device configured to use said temperature data to remove the effects of skin depth of CSF shunt implantation, skin thermal conductivity and skin thermal diffusivity from temperature data collected by said first, second and third pluralities of temperature sensors, and said sensor processing device further configured to determine a flow rate of said CSF through said CSF shunt when a temperature source is applied to said pad.