Multi-modality ablation device

Abstract

An instrument for ablation of tissue. The instrument including: a body having at least one surface for contacting a tissue surface, the at least one surface being substantially planar; an ultrasonic transducer disposed in the body for generating ultrasonic energy and directing at least a portion of the ultrasonic energy to the tissue surface, the ultrasonic transducer being operatively connected to an ultrasonic generator; at least one radio-frequency electrode disposed on the at least one surface for directing radio frequency energy to the tissue surface, the at least one radio-frequency electrode being operatively connected to a power source; and one or more switches for selectively coupling at least one of the ultrasonic transducer to the ultrasonic generator and the at least one radio-frequency electrode to the power source.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates generally to medical instrumentation, and more particularly, to a multi-modality ablation device. [0003] 2. Prior Art [0004] Ultrasonic and radio frequency instruments are well known in the medical arts. Such instrumentation may be used to make lesions in tissue, but are also used to cut and coagulate tissue and blood, respectively. Typically, ultrasonic instrumentation has an ultrasonic transducer at a working end of the instrument, while radio frequency instruments have one or more electrodes at a working end of the instrument. Each of the working ends is typically separated from a handle or other manipulation means by an elongated shaft. [0005] Instruments utilizing radio frequency energy perform well for single-sided ablation of thin tissue. However, this modality can only ablate thicker tissue at the expense of lesion width. Creating wider lesions with radio frequency energy may re...

AI Technical Summary

Benefits of technology

The present invention provides ablation devices and methods that use both ultrasonic and radio-frequency energy to create lesions in tissue with minimal adverse effects such as excessive peripheral thermal damage to tissue. The devices and methods selectively direct the energy to the tissue surface using an ultrasonic transducer and a radio-frequency electrode, which can be powered separately or simultaneously. The instruments have one or more switches for selectively coupling the ultrasonic and radio-frequency energy sources to the tissue surface. The methods also involve measuring the tissue thickness and applying the energy based on the measured thickness. The invention provides improved ablation devices and methods that overcome the disadvantages of conventional instruments.

Problems solved by technology

However, this modality can only ablate thicker tissue at the expense of lesion width.

Creating wider lesions with radio frequency energy may result in damage to critical peripheral tissue structures.

Beyond 6 mm in tissue depth, radio frequency energy may not achieve lesion transmurality.

However, for thin tissue, ultrasound may be ineffective as the ultrasound energy is focused in blood, not in the tissue.

Images