Elastographic imaging of in vivo soft tissue
AssigneeWisconsin Alumni Research Foundation
InventorsTomy Varghese, James A. Zagzebski, Udomchai Techavipoo, Quan Chen
Life of this patent
Estimating the term…
Abstract
Elastographic images provide visualization in two or three dimensions of RF ablation lesions to guide in the ablation process. Compression may be applied using the RF probe. A similar technique may be applied to in vivo imaging of soft tissue without ablation.
Claims36
A method of monitoring RF ablation of tissue comprising the steps of:
- (a) inserting an ablation electrode into an ablation region of the tissue and applying an RF ablation current to the ablation region;
- (b) obtaining a baseline image of the region indicating tissue location;
- (c) applying compression to the region;
- (d) obtaining a compression image of the region indicating new tissue locations;
- and
- (e) processing the baseline and compression images to obtain an image indicating elasticity of the tissue in the region such as may demarcate the lesion formed by the RF ablation.
The method of claim wherein the ultrasonic transducer is selected from the group consisting of:
- 1 D, 1.5 D and 2 D transducers.
A method of medical imaging comprising the steps of:
- (a) inserting a probe into a region of tissue to be imaged;
- (b) compressing tissue of the region using the probe;
- (c) obtaining at least one image of the region indicating tissue movement under compression by the probe;
- and
- (d) processing the image to obtain an indication of elasticity of the tissue in the region.
An apparatus for producing elastographic images of internal structures comprising:
- a probe insertable into the body to a region of the internal body structure;
- a compression fixture holding the probe to apply a controlled compression to the region during image acquisition of the region.
A method of three-dimensional medical imaging of in vivo tissue comprising the steps of:
- (a) obtaining a baseline image of the tissue along a plane through the tissue;
- (b) compressing the tissue;
- (c) obtaining a compression image of the tissue along the plane through the tissue;
- (d) processing the baseline and compression images to obtain an image indicating elasticity of the tissue in the plane;
- (e) repeating steps (a)-(d) for a set of adjacent planes;
- and
- (f) displaying a three-dimensional representation of the in vivo tissue;
- wherein the tissue is a lesion and including the step of calculating the lesion volume.
A method of monitoring RF ablation of tissue comprising the steps of:
- (a) inserting an ablation electrode into an ablation region of the tissue;
- (b) applying an RF ablation current to the ablation region;
- (c) obtaining ultrasound images of the region at periodic intervals indicating apparent tissue locations;
- and
- (e) processing the images to obtain displacement images.
- (f) accumulating displacement from displacement images.
- (g) taking the gradient of the accumulated displacements at specified times to obtain images indicating temperature of the tissue in the region such as may demarcate the lesion formed by the RF ablation.
A method of monitoring RF ablation of tissue comprising the steps of:
- (a) inserting a percutaneous probe into a region of the tissue;
- (b) introducing a low frequency vibration or oscillation of the probe using a single frequency or a chord of frequencies;
- (c) imaging the mechanical shear waves generated using Doppler techniques;
- and
- (d) processing the Doppler information to generate images indicating tissue stiffness or elasticity.
A method of monitoring RF ablation of tissue comprising the steps of:
- inserting a percutaneous probe into a region of the tissue:
- (a) introducing a low frequency vibration or oscillation of the probe.
- (b) fill k-space information during similar phases in the vibration for MR elastography;
- and
- (c) process the k-space information to generate MR elastograms.
Dependencies are inferred from the claim text.