Patent ID: 7520862
Filing Date: 2009-04-21
Classification: A61M

Abstract:
1. A method for evaluating an internal cerebrospinal fluid (CSF) flow rate using external measurements, said CSF flow rate occurring in a CSF shunt within a body of a patient, and said CSF shunt transmitting said CSF between differing locations of said body, the method comprising: (a) applying a plurality of temperature sensors to said body over said CSF shunt at exterior locations on said body to determine an externally determined CSF flow rate signal representative of said CSF flow rate to provide an externally determined CSF flow rate; (b) applying a background temperature sensor to said body at an exterior location on said body to determine an externally measured background induced error correction signal representative of a temperature of said exterior of said body simultaneously with said evaluating of said CSF flow rate for correcting a measurement error induced in said externally determined CSF flow rate signal by a background condition; (c) adjusting said CSF flow rate determination in accordance with said externally measured background induced error correction signal to provide a more accurate representation of said externally determined CSF flow rate, whereby said more accurate representation of said CSF flow rate determination is determined independently of any internally determined temperature signals provided in accordance with any temperature sensors located in the interior of said body, and whereby said CSF flow rate determination is (i) provided only according to external measurement and (ii) corrected only according to external measurement performed simultaneously with said evaluating of said externally determined CSF flow rate; and (d) whereby said CSF flow rate determination is provided according to a comparison of temperature values that are measured simultaneously with said evaluating of said externally determined CSF flow rate only and independently of any comparison with a predetermined control value of temperature for controlling a temperature of a fluid to make said temperature of a fluid equal to said predetermined control value of temperature.