Estimation of lesion size
AssigneesBiosense Webster (Israel) Ltd., University of Oklahoma Health Sciences Center
InventorsMeir Bar-Tal, Erez Silberschein, Assaf Rubissa, Garth Francis Constantine, Hiroshi Nakagawa
Life of this patent
Estimating the term…
Abstract
A method, consisting of ablating tissue for a time period, measuring a contact force applied during the time period, and measuring a power used during the time period. The method further includes ceasing ablating the tissue when a desired size of a lesion produced in the tissue, as estimated using an integral over the time period of a product of the contact force raised to a first non-unity exponent and the power raised to a second non-unity exponent, is reached.
Claims9
A method for ablating tissue over a time period, comprising:
- providing a probe;
- selecting a desired depth for a lesion as estimated by an ablation index defined as
- Depthγ(T)=C∫0TCFα(t)Pβ(t)dt
- wherein
- F is an instantaneous contact force applied by the probe during the time period;
- P is an instantaneous power applied by the probe during the time period;
- T is the time period;
- α, β and γ are numerical exponents having values not equal to unity;
- and
- C is a constant of proportionality;
- selecting values of α, β and γ;
- ablating the tissue with the probe;
- measuring the instantaneous contact force F;
- measuring the instantaneous power;
- and
- ceasing ablating the tissue when the desired depth of the lesion is produced in the tissue, as estimated using the ablation index.
An apparatus, comprising:
- a probe configured to ablate tissue for a time period;
- and
- a processor configured to:
- energize the probe in accordance with an ablation index defined as:
- Depthγ(T)=C∫0TCFα(t)Pβ(t)dt
- wherein
- F is an instantaneous contact force applied by the probe during the time period;
- P is an instantaneous power applied by the probe during the time period;
- T is the time period;
- α, β and γ are user-selected numerical exponents having values not equal to unity;
- and
- C is a constant of proportionality;
- measure an instantaneous contact force applied by the probe during the time period,
- measure an instantaneous power used for ablating the tissue during the time period, and
- cease ablating the tissue when a desired depth of lesion is produced in the tissue, as estimated using the ablation index.
Dependencies are inferred from the claim text.