Energy delivery algorithm filter pre-loading

• US 8,152,802 B2
• Filed: 01/12/2009
• Issued: 04/10/2012
• Est. Priority Date: 01/12/2009
• Status: Active Grant

• Current Assignee: Covidien LP (Medtronic Plc)
• Original Assignee: Tyco Healthcare Group LP (Medtronic Plc)
• Inventors: Podhajsky, Ronald J., Heckel, Donald W.
• Primary Examiner(s): BOUCHELLE, LAURA A
• Application Number:
  US12/351,970
• Publication Number:
  US 20100179535A1
• Time in Patent Office: 1,184 Days
• Field of Search: 606 39- 42, 606/45, 606 48- 52, 606/34, 606/37, 606/38, 607/96, 607/98, 607/99, 607/101, 607/122
• US Class Current: 606/34
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/1442 Probes having pivoting end effectors, e.g. forceps
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00589 Coagulation
• CPC Class Codes: A61B 2018/00601 Cutting
• CPC Class Codes: A61B 2018/00702 Power or energy
• CPC Class Codes: A61B 2018/00773 Sensed parameters
• CPC Class Codes: A61B 2018/00875 Resistance or impedance

Abstract

A method for controlling energy applied to tissue in two or more states as a function of a detected tissue property is provided. The method includes the steps of: determining an initial value of the detected tissue property, recursively processing the detected tissue property to obtain an averaged value thereof, updating the recursively processing step with the initial value of the detected tissue property and transitioning between two or more states based on a comparison of averaged values obtained by two or more recursive filters.

Claims

1. A method for controlling energy applied to tissue in at least two states as a function of at least one detected tissue property, comprising the steps of:

providing at least two recursive filters configured to recursively process the at least one detected tissue property to obtain an averaged value of the at least one detected tissue property;

applying energy at a baseline level to the tissue;

determining an initial value of the at least one detected tissue property;

ramping the energy from a baseline level to an initial level;

preloading the at least two recursive filters with the initial value of the at least one detected tissue property;

recursively processing the at least one detected tissue property to obtain the averaged value of the at least one detected tissue property; and

transitioning between the at least two states based on a comparison of averaged values.

2. The method according to claim 1, wherein each of the at least two recursive filters of the providing step is a single pole recursive filter having a historical value and a current value.

3. The method according to claim 2, wherein the preloading step further includes the step of:

preloading the initial value of the at least one detected tissue property as the historical value of each of the at least two filters.

4. The method according to claim 2, further including the steps of:

calculating the difference between averaged values obtained by the at least two recursive filters; and

transitioning between the at least two states based on a comparison between the difference between averaged values and a predetermined threshold.

5. A method for controlling energy applied to tissue in at least two states as a function of at least one detected tissue property, comprising the steps of:

providing at least two recursive filters configured to recursively process at least one detected tissue property to obtain an averaged value of the at least one detected tissue property;

applying energy at a baseline level to the tissue;

determining an initial value of the at least one detected tissue property;

ramping the energy from a baseline level to an initial level;

preloading the at least two filters with the initial value of the at least one detected tissue property; and

transitioning between the at least two states based on a comparison of averaged values obtained by the at least two filters.

6. The method according to claim 5, wherein each of the at least two filters of the providing step is a single pole recursive filter having a historical value and a current value.

7. The method according to claim 6, wherein the preloading step further includes the step of:

preloading the initial value of the at least one detected tissue property as the historical value of each of the at least two filters.

8. The method according to claim 6, further including the steps of:

calculating the difference between averaged values obtained by the at least two recursive filters; and

transitioning between the at least two states based on a comparison between the difference between averaged values and a predetermined threshold.

9. A system for controlling energy applied to tissue in at least two states as a function of at least one detected tissue property, comprising:

a memory configured to store an initial value of at least one detected tissue property; and

a microprocessor configured to execute at least two recursive filters configured to recursively process the at least one detected tissue property to obtain an averaged value of the at least one detected tissue property and to preload the at least two recursive filters with an initial value of the at least one detected tissue property detected while applying a baseline level of energy to the tissue before ramping the energy to an initial level, wherein the microprocessor is further configured to transition between the at least two states based on a difference between averaged values obtained by the at least two recursive filters.

10. The system according to claim 9, wherein each of the at least two recursive filters of the providing step is a single pole recursive filter having a historical value and a current value.

11. The system according to claim 10, wherein the microprocessor is further configured to preload the initial value of the at least one detected tissue property as the historical value of each of the at least two recursive filters.

12. The system according to claim 9, wherein the microprocessor is further configured to calculate the difference between averaged values obtained by the at least two recursive filters and to transition between the at least two states based on a comparison between the difference between averaged values and a predetermined threshold.