Method of employing a transit time ultrasound sensor

• US 7,469,598 B2
• Filed: 03/26/2007
• Issued: 12/30/2008
• Est. Priority Date: 05/29/2003
• Status: Expired due to Term

• Current Assignee: Transonic Systems, Inc. (Measurement Innovations Corp.)
• Original Assignee: Transonic Systems, Inc. (Measurement Innovations Corp.)
• Inventors: Drost, Cornelis J., Shkarlet, Yuri
• Primary Examiner(s): Williams; Hezron
• Assistant Examiner(s): MILLER, ROSE MARY
• Application Number:
  US11/691,222
• Publication Number:
  US 20070186681A1
• Time in Patent Office: 645 Days
• Field of Search: 73/191, 73/190.3, 738/612.7, 738/612.8, 738/612.9, 738/613.1, 738/612.6, 738/612.5, 738/611.8, 738/610.8, 738/610.5, 738/665, 738/61, 600/459
• US Class Current: 73/861.18
• CPC Class Codes: A61B 5/6876 Blood vessel
• CPC Class Codes: A61B 5/6884 Clamps or clips
• CPC Class Codes: A61B 8/06 Measuring blood flow measuring volume flow in general G01F, e.g. G01F1/66, G01F1/72; measuring speed of fluids in general G01P5/00
• CPC Class Codes: A61B 8/065 to determine blood output from the heart in general A61B5/029

Abstract

A method is provided for employing a transit time ultrasound sensor, wherein the sensor can be used for the measurement of liquid flow in a conduit, the sensor having an acoustic path formed of materials matched in ultrasound properties to a flow under test, and designed to conform to the shape of the conduit. The transit time ultrasound sensor can be configured as a clamp on device, wherein the conduit walls are constructed from such an ultrasonically-matched material. Alternately, the transit time ultrasound sensor can be employed in a perivascular configuration, wherein the ultrasonically-matched material is operably intermediate the blood vessel and the sensor.

Claims

1. A method of employing a transit time ultrasound sensor, the method comprising:

(a) disposing a solid acoustic couplant within an acoustic path of the transit time ultrasound sensor, the solid acoustic couplant having an acoustic velocity within 10 percent of a fluid flow in a conduit in the acoustic path and an acoustic impedance within 10 percent of the fluid flow and a wall of the conduit.

2. The method as of claim 1, further comprising determining one of a volume flow or a cardiac output corresponding to the fluid flow in the acoustic path of the transit time ultrasound sensor.

3. The method as in claim 1, further comprising passing a substantially homogenous level of ultrasonic energy through the fluid flow in the acoustic path of the transit time ultrasound sensor.

4. The method of claim 1, further comprising illuminating a substantially full field of the fluid flow in the acoustic path of the transit time ultrasound sensor.

14. The method as in claims 1, or 10, further comprising illuminating a substantially full field of the conduit in the acoustic path of the transit time ultrasound sensor.

15. The method of claims 1, 5 or 10, further comprising employing a planar transducer in the transit time ultrasound sensor.

5. A method of employing a transit time ultrasound sensor, the method comprising:

(a) locating a solid acoustic couplant in an acoustic path of the transit time ultrasound sensor; and

(b) passing an acoustic wave having a nominal period and a planar wave front along the acoustic path, at least a portion of the planar wave front along the acoustic path reaching a second transducer within ¼

of the nominal period.

6. The method of claim 5, further comprising determining one of a volume flow or a cardiac output corresponding to a fluid flow in a conduit located in the acoustic path of the transit time ultrasound sensor.

7. The method of claim 5, further comprising passing a substantially homogenous level of ultrasonic energy through a fluid flow in a conduit located in the acoustic path of the transit time ultrasound sensor.

8. The method of claim 5, further comprising illuminating a substantially full field of a fluid flow in a conduit located in the acoustic path of the transit time ultrasound sensor.

9. The method of claim 5, further comprising illuminating a substantially full field of a conduit located in the acoustic path of the transit time ultrasound sensor.

10. A method of employing a transit time ultrasound sensor, the method comprising:

(a) locating a conduit having a curvilinear cross sectional profile in an acoustic path of a transit time ultrasound sensor; and

(b) at least partially defining a measuring channel in the acoustic path to match the curvilinear conduit cross-sectional profile with a solid acoustic couplant in the acoustic path.

11. The method of claim 10, further comprising determining one of a volume flow or a cardiac output corresponding to a fluid flow in the conduit in the acoustic path of the transit time ultrasound sensor.

12. The method of claim 10, further comprising passing a substantially homogenous level of ultrasonic energy through a fluid flow in the conduit in the acoustic path of the transit time ultrasound sensor.

13. The method of claim 10, further comprising illuminating a substantially full field of a fluid flow in the conduit in the acoustic path of the transit time ultrasound sensor.