Real Time CSF Flow Measurement System & Method

• US 20150045717A1
• Filed: 10/14/2014
• Published: 02/12/2015
• Est. Priority Date: 05/28/2010
• Status: Abandoned Application

• Current Assignee: ShuntCheck, Inc.
• Original Assignee: ShuntCheck, Inc.
• Inventors: Swoboda, Marek, Hochman, Matias Gabriel, Mattiucci, Mark Evan, Fritz, Frederick J.
• Application Number:
  US14/513,856
• Publication Number:
  US 20150045717A1
• Time in Patent Office: Days
• US Class Current: 604/9
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/031 Intracranial pressure
• CPC Class Codes: A61B 5/032 Spinal fluid pressure
• CPC Class Codes: A61M 27/006 Cerebrospinal drainage; Accessories therefor, e.g. valves
• CPC Class Codes: A61M 5/168 Means for controlling media flow to the body or for metering media to the body, e.g. drip meters, counters ; Monitoring media flow to the body flow control in general G05D7/00
• CPC Class Codes: A61M 5/16836 by sensing tissue properties at the infusion site, e.g. for detecting infiltration detecting tissue temperature for diagnostic purposes A61M39/0247
• CPC Class Codes: G01F 1/684 Structural arrangements; Mounting of elements, e.g. in relation to fluid flow

Abstract

A system for measuring quantitative CSF flow in shunt tubing implanted under the skin. The system includes an array of thermo-sensors clustered in three sections, cooling device, placed on the skin surface and an associated data acquisition and analysis device. Two sensor sections are placed over the shunt on the skin and measure real time temperature responses related to CSF movement. One array placed adjacent the cooling device collects data on thermal properties of skin including skin thermal conductivity, specific heat, diffusivity, perfusion, and thermal inertia. The method involves assessing thermal properties of skin and measuring CSF flow in shunt tubing. The method is useful for shunt patency assessment, CSF valve adjustment procedures and CSF flow measurements related to CSF over drainage. Alternatively, only one section of sensors need be used when determining relative CSF flow, without the need to determine thermal skin properties and by applying the cooling device continuously.

Claims

1. 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

at least one temperature sensor associated with a temperature source that is positioned over the CSF shunt whenever said pad is placed against the skin and wherein said temperature source is applied continuously against the skin; and

a sensor processing device that is electrically coupled to said pad for receiving temperature data from each of said temperature sensors during said continuous application of said temperature source, and for determining a flow rate of said CSF through said CSF shunt from said temperature data.

2. The apparatus of claim 1 wherein said sensor processing device controls the activation of said temperature source.

3. The apparatus of claim 1 wherein said temperature source is a Peltier device.

4. The apparatus of claim 3 wherein said Peltier device maintains a temperature that differs from a skin temperature.

5. The apparatus of claim 4 wherein said temperature differs from said skin temperature by approximately 7°

-14°

C.

6. The apparatus of claim 3 wherein said continuous application of said temperature source is at least 5 minutes.

7. The apparatus of claim 1 further comprising 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.

8. The apparatus of claim 1 wherein said at least one temperature sensor associated with a temperature source comprises a temperature sensor that is positioned on said temperature source or is configured to be positioned between said temperature source and the skin surface.

9. The apparatus of claim 7 wherein said at least one temperature sensor associated with a temperature source further comprises at least one other temperature sensor disposed adjacent said temperature source.

10. A method for determining cerebrospinal fluid (CSF) flow rate in an implanted CSF shunt, said method comprising:

applying a first plurality of temperature sensors against the skin over the location of the CSF shunt and wherein only one of said first plurality of temperature sensors is aligned with the CSF shunt;

associating at least one temperature sensor with a temperature source;

activating said temperature source against the skin continuously and aligned with the CSF shunt, said activating said temperature source comprises applying a temperature to the skin continuously that is different from a skin temperature;

collecting temperature data from said temperature sensors during said continuous activation of said temperature source; and

determining a flow rate of the CSF through the CSF shunt from said temperature data.

11. The method of claim 10 wherein said temperature source is a Peltier device.

12. The method of claim 11 wherein said Peltier device maintains a temperature that differs from a skin temperature.

13. The method of claim 12 wherein said temperature differs from said skin temperature by approximately 7°

-14°

C.

14. The method of claim 10 wherein said continuous activation of said temperature source is at least 5 minutes.

15. The method of claim 10 wherein said step of applying a first plurality of temperature sensors comprises applying a second plurality of temperature sensors against the skin over the location of the CSF shunt, downstream of said first plurality of temperature sensors, and wherein only one of said second plurality of temperature sensors is aligned with the CSF shunt.

16. The method of claim 10 wherein said step of associating at least one temperature sensor with a temperature source comprises positioning a temperature sensor on said temperature source or positioning said temperature sensor between said temperature source and the skin surface.

17. The method of claim 16 wherein said step of positioning a temperature sensor on said temperature or positioning said temperature sensor between said temperature sensor and the skin surface further comprises positioning at least one other temperature sensor adjacent said temperature source.