WEIGHT-BASED CALIBRATION SYSTEM FOR A PRESSURE SENSITIVE CATHETER

• US 20110307207A1
• Filed: 06/10/2010
• Published: 12/15/2011
• Est. Priority Date: 06/10/2010
• Status: Active Grant

• Current Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Original Assignee: Biosense Webster Incorporated (Johnson & Johnson)
• Inventors: Govari, Assaf, Altmann, Andres Claudio, Ephrath, Yaron
• Granted Patent: US 8,798,952 B2
• Time in Patent Office: Days
• US Class Current: 702/98
• CPC Class Codes: A61B 2560/0223 of calibration, e.g. protocols for calibrating sensors
• CPC Class Codes: A61B 2560/0228 using calibration standards
• CPC Class Codes: A61B 5/1495 Calibrating or testing of in-vivo probes
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure

Abstract

A calibration apparatus includes a fixture, which is coupled to hold a distal end of a medical probe. A plurality of weights, which have respective masses and respective bottom surfaces that are oriented at respective angles with respect to the distal end of the probe, are coupled to rest on a distal tip of the probe so as to apply to the distal tip respective force vectors that cause a deformation of the distal tip relative to the distal end. A calibration processor is configured to receive from the probe measurements indicative of the deformation of the distal tip in response to the force vectors, and to compute, based on the measurements, the masses and the angles, calibration coefficients for assessing the force vectors as a function of the measurements.

Claims

1. A calibration apparatus, comprising:

a fixture, which is coupled to hold a distal end of a medical probe;

a plurality of weights, having respective masses and respective bottom surfaces that are oriented at respective angles with respect to the distal end of the probe, which are coupled to rest on a distal tip of the probe so as to apply to the distal tip respective force vectors that cause a deformation of the distal tip relative to the distal end; and

a calibration processor, which is configured to receive from the probe measurements indicative of the deformation of the distal tip in response to the force vectors, and to compute, based on the measurements, the masses and the angles, calibration coefficients for assessing the force vectors as a function of the measurements.

2. The apparatus according to claim 1, and comprising a sensing device coupled to the fixture and configured to measure respective downwards components of the force vectors, wherein the calibration processor is configured to verify the calibration coefficients responsively to the measured downward components.

3. The apparatus according to claim 1, wherein the bottom surfaces are coated with a non-stick material.

4. The apparatus according to claim 1, wherein the bottom surfaces are coated with a material having a surface texture that matches an inner surface texture of a body organ in which the probe is to operate.

5. The apparatus according to claim 1, wherein the calibration processor is configured to store the calibration coefficients in a memory that is coupled to the probe.

6. The apparatus according to claim 5, wherein the memory comprises an Electronically Erasable Programmable Read Only Memory (E²PROM).

7. A method for calibration, comprising:

holding a distal end of a medical probe in a fixture;

lowering onto a distal tip of the probe weights, having respective masses and respective bottom surface that are oriented at respective angles with respect to the distal tip, so as to apply to the distal tip respective force vectors that cause a deformation of the distal tip relative to the distal end;

receiving from the probe measurements indicative of the deformation of the distal tip in response to the force vectors; and

computing, based on the measurements, the masses and the angles, calibration coefficients for assessing the force vectors as a function of the measurements.

8. The method according to claim 7, and comprising measuring respective downward components of the force vectors using a sensing device coupled to the fixture, and verifying the calibration coefficients responsively to the measured downward components.

9. The method according to claim 7, wherein the bottom surfaces are coated with a non-stick material.

10. The method according to claim 7, wherein the bottom surfaces are coated with a material having a surface texture that matches an inner surface texture of a body organ in which the probe is to operate.

11. The method according to claim 7, and comprising storing the calibration coefficients in a memory coupled to the probe.

12. The method according to claim 11, wherein the memory comprises an Electronically Erasable Programmable Read Only Memory (E²PROM).