Ultrasound Image Processing To Render Three-Dimensional Images From Two-Dimensional Images

• US 20090005679A1
• Filed: 06/30/2007
• Published: 01/01/2009
• Est. Priority Date: 06/30/2007
• Status: Active Grant

• Current Assignee: St. Jude Medical (Abbott Laboratories Incorporated)
• Original Assignee: Ep Medsystems Incorporated (Abbott Laboratories Incorporated)
• Inventors: Dala-Krishna, Praveen
• Granted Patent: US 8,057,394 B2
• Time in Patent Office: Days
• US Class Current: 600/437
• CPC Class Codes: A61B 8/0883 for diagnosis of the heart
• CPC Class Codes: A61B 8/12 in body cavities or body tracts, e.g. by using catheters catheters per se A61M25/00
• CPC Class Codes: A61B 8/4245 involving determining the position of the probe, e.g. with respect to an external reference frame or to the patient
• CPC Class Codes: A61B 8/445 Details of catheter construction
• CPC Class Codes: A61B 8/4483 characterised by features of the ultrasound transducer
• CPC Class Codes: A61B 8/466 adapted to display 3D data 3D imaging and stereoscopic displays in devices for short-range imaging with acoustic waves G01S15/8993 and G01S7/52068, respectively; 3D image rendering G06T15/00; manipulating 3D models for computer graphics G06T19/00
• CPC Class Codes: A61B 8/483 involving the acquisition of a 3D volume of data
• CPC Class Codes: A61B 8/5284 involving retrospective matching to a physiological signal
• CPC Class Codes: A61B 8/543 involving acquisition triggered by a physiological signal
• CPC Class Codes: G06T 13/20 3D [Three Dimensional] animation
• CPC Class Codes: G06T 15/02 Non-photorealistic rendering
• CPC Class Codes: G06T 2200/08 involving all processing steps from image acquisition to 3D model generation
• CPC Class Codes: G06T 2207/10068 Endoscopic image
• CPC Class Codes: G06T 2207/10136 3D ultrasound image
• CPC Class Codes: G06T 2207/30048 Heart; Cardiac
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06T 7/12 Edge-based segmentation
• CPC Class Codes: G06T 7/33 using feature-based methods
• CPC Class Codes: G06T 7/80 Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration

Abstract

Methods for processing two-dimensional ultrasound images from an intracardiac ultrasound imaging catheter provide improved image quality and enable generating three-dimensional composite images of the heart. Two-dimensional ultrasound images are obtained and stored in conjunction with correlating information, such as time or an electrocardiogram. Images related to particular conditions or configurations of the heart can be processed in combination to reduce image noise and increase resolution. Images may be processed to recognize structure edges, and the location of structure edges used to generate cartoon rendered images of the structure. Structure locations may be averaged over several images to remove noise, distortions and blurring from movement.

Claims

1. A method for processing ultrasound images obtained from an intracardiac ultrasound imaging catheter having a phased array ultrasound transducer, comprising:

receiving a plurality of ultrasound image frames;

detecting edges of tissue structures within each of the plurality of image frames;

determining a spatial location of each of the detected edges in each of the plurality of image frames;

statistically analyzing the spatial locations of detected edges among the plurality of image frames to determine representative spatial locations for the tissue structures; and

generating a cartoon rendering of the tissue structures based upon the representative spatial locations.

2. The method of claim 1, further comprising displaying the cartoon rendering of the tissue structures.

3. The method of claim 1, wherein statistically analyzing spatial locations of detected edges among the plurality of image frames comprises determining an average location of the detected edges among the plurality of image frames.

4. The method of claim 1, wherein statistically analyzing spatial locations of detected edges among the plurality of image frames comprises determining a mean location of the detected edges among the plurality of image frames.

5. The method of claim 1, wherein statistically analyzing spatial locations of detected edges among the plurality of image frames comprises determining a weighted average location of the detected edges among the plurality of image frames.

6. The method of claim 1, further comprising:

recognizing a tissue structure;

matching the recognized tissue structure to a model of heart tissue structures; and

back-calculating a location and orientation of the phased array ultrasound transducer based upon the results of matching the recognized tissue structure to the model of heart tissue structures.

7. The method of claim 6, further comprising registering the recognized tissue structure within an external coordinate reference frame.

8. The method of claim 2, wherein statistically analyzing spatial locations of detected edges among the plurality of image frames comprises calculating a moving average of spatial locations of detected edges among two or more image frames selected from a stream of image frames.

9. The method of claim 1,

wherein the steps of statistically analyzing the spatial locations of detected edges among the plurality of image frames to determine representative spatial locations for the tissue structures and generating cartoon renderings of the tissue structures based upon the representative spatial locations are performed for each of a plurality of transducer rotational orientations to generate a plurality of cartoon rendered image frames corresponding to the plurality of transducer rotational orientations, and

further comprising combining the plurality of cartoon rendered image frames using their corresponding transducer orientations to generate a three-dimensional cartoon rendering of tissue structure.

10. A method for processing a plurality of intracardiac ultrasound images stored in a computer readable memory that were obtained from an intracardiac ultrasound imaging catheter having a phased array ultrasound transducer, comprising:

receiving from the computer readable memory a plurality of ultrasound image frames and data indicating a transducer rotational orientation associated with each one of the plurality of ultrasound image frames;

detecting edges of tissue structures within each of the plurality of image frames;

determining a spatial location of each of the detected edges in each of the plurality of image frames;

statistically analyzing the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation to determine representative spatial locations for the tissue structures imaged from the approximately equal transducer rotational orientation;

generating a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation;

repeating the steps of statistically analyzing the spatial locations of the detected edges and generating cartoon rendered image frames for each of a plurality of approximately equal transducer rotational orientations to generate a plurality of cartoon rendered image frames; and

combining the plurality of cartoon rendered image frames using their corresponding approximately equal transducer rotation orientations to generate a three-dimensional cartoon rendering of tissue structure.

11. The method of claim 10, further comprising displaying the cartoon rendering of the tissue structures.

12. The method of claim 10, wherein statistically analyzing spatial locations of detected edges among the plurality of image frames comprising determining an average location of the detected edges among the plurality of image frames.

13. The method of claim 10, wherein statistically analyzing spatial locations of detected edges among the plurality of image frames comprising determining a mean location of the detected edges among the plurality of image frames.

14. The method of claim 10, wherein statistically analyzing spatial locations of detected edges among the plurality of image frames comprising determining a weighted average location of the detected edges among the plurality of image frames.

15. The method of claim 10, further comprising:

recognizing a tissue structure;

matching the recognized tissue structure to a model of heart tissue structures; and

back-calculating an imaging perspective of the phased array ultrasound transducer based upon the results of matching the recognized tissue structure to the model of heart tissue structures.

16. The method of claim 15, further comprising registering the recognized tissue structure within an external coordinate reference frame.

17. The method of claim 10, further comprising:

receiving from computer memory an electrocardiogram signal corresponding in time of recording to the plurality of ultrasound image frames, wherein, the steps of statistically analyzing the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation and generating a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation are performed for a subset of the plurality of image frames corresponding to a trigger event in the electrocardiogram signal; and

combining the plurality of cartoon rendered image frames within the subset of the plurality of image frames corresponding to the trigger event in the electrocardiogram signal using their respective corresponding approximately equal transducer rotation orientations to generate a three-dimensional cartoon rendering of tissue structure corresponding to the trigger event.

18. The method of claim 17, wherein the trigger event is a pacing pulse.

19. The method of claim 10, further comprising:

receiving from the computer memory an electrocardiogram signal corresponding in time of recording to the plurality of ultrasound image frames, wherein, the steps of statistically analyzing the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation and generating a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation are performed for subsets of the plurality of image frames corresponding to like portions of the electrocardiogram signal; and

combining the plurality of cartoon rendered image frames within each subset of the plurality of image frames corresponding to like portions of the electrocardiogram signal using their respective corresponding approximately equal transducer rotation orientations to generate a four-dimensional cartoon rendering of tissue structure.

20. A method for displaying intracardiac ultrasound images stored in a computer readable memory that were obtained from an intracardiac ultrasound imaging catheter having a phased array ultrasound transducer, comprising:

receiving from the computer readable memory a plurality of ultrasound image frames and data indicating a transducer rotational orientation associated with each one of the plurality of ultrasound image frames;

detecting edges of tissue structures within each of the plurality of image frames;

determining a spatial location of each of the detected edges in each of the plurality of image frames;

statistically analyzing the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation to determine representative spatial locations for the tissue structures imaged from the approximately equal transducer rotational orientation;

generating a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation;

repeating the steps of statistically analyzing the spatial locations of the detected edges and generating cartoon rendered image frames for each of a plurality of approximately equal transducer rotational orientations to generate a plurality of cartoon rendered image frames;

combining the plurality of cartoon rendered image frames using their corresponding approximately equal transducer rotation orientations to generate a three-dimensional cartoon rendering of tissue structure;

presenting a graphical user interface configured to permit a user to indicate a portion of the three-dimensional cartoon rendering of tissue structure to be displayed;

receiving user inputs indicating a portion of the three-dimensional cartoon rendering of tissue structure to be displayed; and

generating a display corresponding to the user inputs.

21. A system for intracardiac imaging, comprising:

an ultrasound imaging catheter comprising a phased array ultrasound transducer;

an ultrasound beamformer circuit electronically coupled to the ultrasound imaging catheter;

a programmable processor coupled to the ultrasound beamformer circuit and

computer readable memory electronically coupled to the programmable processor and having stored therein software instructions which adapt and configure the programmable processor to;

store a plurality of ultrasound image frames in memory;

store in memory a rotational orientation of the transducer corresponding to each of the plurality of ultrasound image frames;

detect edges of tissue structures within each of the plurality of image frames;

determine a spatial location of each of the detected edges in each of the plurality of image frames;

statistically analyze the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation to determine representative spatial locations for the tissue structures imaged from the approximately equal transducer rotational orientation;

generate a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation;

repeat the steps of statistically analyzing the spatial locations of the detected edges and generating cartoon rendered image frames for each of a plurality of approximately equal transducer rotational orientations to generate a plurality of cartoon rendered image frames; and

combine the plurality of cartoon rendered image frames using their corresponding approximately equal transducer rotation orientations to generate a three-dimensional cartoon rendering of tissue structure.

22. The system of claim 21, wherein the computer readable memory has stored therein software instructions which further adapt and configure the programmable processor to display the cartoon rendering of the tissue structures.

23. The system of claim 21, wherein the computer readable memory has stored therein software instructions which further adapt and configure the programmable processor to statistically analyze spatial locations of detected edges among the plurality of image frames by determining an average location of the detected edges among the plurality of image frames.

24. The system of claim 21, wherein the computer readable memory has stored therein software instructions which further adapt and configure the programmable processor to:

recognize a tissue structure;

match the recognized tissue structure to a model of heart tissue structures; and

back-calculate an imaging perspective of the phased array ultrasound transducer based upon the results of matching the recognized tissue structure to the model of heart tissue structures.

25. The system of claim 24, wherein the computer readable memory has stored therein software instructions which further adapt and configure the programmable processor to register the recognized tissue structure within an external coordinate reference frame.

26. The system of claim 21, wherein the computer readable memory has stored therein software instructions which further adapt and configure the programmable processor to:

receive and store an electrocardiogram signal corresponding in time of recording to the plurality of ultrasound image frames;

perform the steps of statistically analyzing the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation and generating a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation for a subset of the plurality of image frames corresponding to a trigger event in the electrocardiogram signal; and

combine the plurality of cartoon rendered image frames within the subset of the plurality of image frames corresponding to the trigger event in the electrocardiogram signal using their respective corresponding approximately equal transducer rotation orientations to generate a three-dimensional cartoon rendering of tissue structure corresponding to the trigger event.

27. The system of claim 21, wherein the computer readable memory has stored therein software instructions which further adapt and configure the programmable processor to:

receive and store an electrocardiogram signal corresponding in time of recording to the plurality of ultrasound image frames;

perform the steps of statistically analyzing the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation and generating a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation for subsets of the plurality of image frames corresponding to like portions of the electrocardiogram signal; and

combine the plurality of cartoon rendered image frames within each subset of the plurality of image frames corresponding to like portions of the electrocardiogram signal using their respective corresponding approximately equal transducer rotation orientations to generate a four-dimensional cartoon rendering of tissue structure.

28. The system of claim 21, wherein the computer readable memory has stored therein software instructions which further adapt and configure the programmable processor to:

present a graphical user interface configured to permit a user to indicate a portion of the three dimensional cartoon rendering of tissue structure to be displayed;

receive user inputs indicating a portion of the three-dimensional cartoon rendering of tissue structure to be displayed; and

generate a display corresponding to the user inputs.

29. A computer readable memory having stored therein software instructions which adapt and configure a programmable processor to perform the steps of:

receiving from memory a plurality of intracardiac ultrasound image frames and data indicating a transducer rotational orientation associated with each one of the plurality of ultrasound image frames;

detecting edges of tissue structures within each of the plurality of image frames;

determining a spatial location of each of the detected edges in each of the plurality of image frames;

statistically analyzing the spatial locations of the detected edges among a subset of the plurality of image frames with an approximately equal transducer rotational orientation to determine representative spatial locations for the tissue structures imaged from the approximately equal transducer rotational orientation; and

generating a cartoon rendered image frame of the tissue structures based upon the representative spatial locations imaged from the approximately equal transducer rotational orientation.

30. The computer readable memory according to claim 30, wherein the software instructions stored therein adapt and configure a programmable processor to perform the further steps of:

repeating the steps of statistically analyzing the spatial locations of the detected edges and generating cartoon rendered image frames for each of a plurality of approximately equal transducer rotational orientations to generate a plurality of cartoon rendered image frames; and

combining the plurality of cartoon rendered image frames using their corresponding approximately equal transducer rotation orientations to generate a three dimensional cartoon rendering of tissue structure.

31. The computer readable memory according to claim 30, wherein the software instructions stored therein adapt and configure a programmable processor to perform the further steps of:

presenting a graphical user interface configured to permit a user to indicate a portion of the three-dimensional cartoon rendering of tissue structure to be displayed;

receiving user inputs indicating a portion of the three-dimensional cartoon rendering of tissue structure to be displayed; and

generating a display corresponding to the user inputs.