Imaging System and Method for Use in Surgical and Interventional Medical Procedures

• US 20130342578A1
• Filed: 08/27/2013
• Published: 12/26/2013
• Est. Priority Date: 10/06/2010
• Status: Active Grant

• Current Assignee: Nuvasive Incorporated
• Original Assignee: Saferay Spine, LLC
• Inventors: Isaacs, Robert E.
• Granted Patent: US 8,792,704 B2
• Time in Patent Office: Days
• US Class Current: 345/634
• CPC Class Codes: G06T 2207/10081 Computed x-ray tomography [CT]
• CPC Class Codes: G06T 2207/10121 Fluoroscopy
• CPC Class Codes: G06T 2207/20104 Interactive definition of region of interest [ROI]
• CPC Class Codes: G06T 2207/20221 Image fusion; Image merging
• CPC Class Codes: G06T 2207/20224 Image subtraction
• CPC Class Codes: G06T 2207/30012 Spine; Backbone
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 7/32 using correlation-based methods
• CPC Class Codes: G06T 7/33 using feature-based methods
• CPC Class Codes: G16H 20/40 relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 30/20 for handling medical images, e.g. DICOM, HL7 or PACS
• CPC Class Codes: G16H 50/70 for mining of medical data, e.g. analysing previous cases of other patients

Abstract

A system and method for displaying images of internal anatomy includes an image processing device configured to provide high resolution images of the surgical field from low resolution scans during the procedure. The image processing device digitally manipulates a previously-obtained high resolution baseline image to produce many representative images based on permutations of movement of the baseline image. During the procedure a representative image is selected having an acceptable degree of correlation to the new low resolution image. The selected representative image and the new image are merged to provide a higher resolution image of the surgical field. The image processing device is also configured to provide interactive movement of the displayed image based on movement of the imaging device, and to permit placement of annotations on the displayed image to facilitate communication between the radiology technician and the surgeon.

Claims

1. A method for generating a display of an image of a patient'"'"'s internal anatomy in a surgical field during a medical procedure, comprising:

acquiring a high resolution baseline image of the surgical field including the patient'"'"'s internal anatomy in a baseline orientation;

digitally manipulating the high resolution baseline image to produce a baseline image set including representative images of the baseline image at a plurality of permutations of movements of the baseline image from the baseline orientation;

acquiring a new image of the surgical field at a lower resolution;

comparing the new image to the representative images in the baseline image set and selecting the representative image having an acceptable degree of correlation with the new image; and

merging the selected representative image with the new image and displaying the merged image.

2. The method of claim 1, wherein the baseline image is selected from the group including a pre-procedure full dose fluoroscopic image, a DRR and a CT scan image.

3. The method of claim 1, wherein the new image is one of a pulse or low dose image.

4. The method of claim 1, wherein:

in the step of digitally manipulating the high resolution image the permutations of movements form a predefined grid of image movements; and

the step of comparing the new image to the representative images of the baseline image set includes comparing overlapping pixels between the representative image and the new image.

5. The method of claim 1, wherein the step of comparing the new image to the representative images of the baseline image set includes:

performing a principal component analysis (PCA) on the pixels of the representative images in the baseline image set to generate one or more PCA vectors;

producing a PCA matrix of PCA vectors for each pixel in a representative image;

generating a column vector for each representative image and the new image of pixel data for each pixel in the image;

performing a matrix multiplication of the PCA matrix and each column vector to generate a new column vector for each representative image and the new image;

obtaining the dot product of the column vector for the new image and the column vector for each of the representative image; and

selecting a representative image for which the dot product is within a pre-determined threshold.

6. The method of claim 1, in which the medical procedure includes tools, instruments, implants or other objects that block or obscure the internal anatomy in an image of the surgical field, wherein the step of comparing the new image to the representative images of the baseline image set includes only comparing portions of the images outside the portions that are blocked or obscured.

7. The method of claim 6, wherein the location of the blocked or obscured portions of the new image are determined by determining which pixels have a value outside a pre-determined threshold.

8. The method of claim 1, wherein:

the step of digitally manipulating the high resolution baseline image includes providing parallel images to each representative image in which the image of certain anatomic features is reduced or enhanced; and

the step of merging the selected representative image includes merging and displaying the parallel image to the selected representative image.

9. An image processing device for generating a display of an image of a patient'"'"'s internal anatomy during a medical procedure, comprising:

a memory for storing a high resolution baseline image of the surgical field including the patient'"'"'s internal anatomy in a baseline orientation and a new image of the surgical field at a low resolution; and

a processor configured to;

digitally manipulate the high resolution baseline image to produce a baseline image set including representative images of the baseline image at a plurality of permutations of movements of the baseline image from the baseline orientation;

perform software instructions for comparing the new image to the representative images in the baseline image set and selecting the representative image having an acceptable degree of correlation with the new image;

digitally merge the selected representative image with the new image; and

generate signals for displaying the merged image on a display device.

10. The image processing device of claim 9, wherein:

the processor is further configured to digitally manipulate the high resolution image such that the permutations of movements form a predefined grid of image movements; and

the software instructions for comparing the new image to the representative images of the baseline image set include instructions for comparing overlapping pixels between the representative image and the new image.

11. The image processing device of claim 9, wherein the software instructions for comparing the new image to the representative images of the baseline image set include instructions for:

performing a principal component analysis (PCA) on the pixels of the representative images in the baseline image set to generate one or more PCA vectors;

producing a PCA matrix of PCA vectors for each pixel in a representative image;

generating a column vector for each representative image and the new image of pixel data for each pixel in the image;

performing a matrix multiplication of the PCA matrix and each column vector to generate a new column vector for each representative image and the new image;

obtaining the dot product of the column vector for the new image and the column vector for each of the representative image; and

selecting a representative image for which the dot product is within a pre-determined threshold.

12. The image processing device of claim 9, in which the medical procedure includes tools, instruments, implants or other objects that block or obscure the internal anatomy in an image of the surgical field, wherein the software instructions for comparing the new image to the representative images of the baseline image set include instructions for only comparing portions of the images outside the portions that are blocked or obscured.

13. The image processing device of claim 12, wherein the processor is configured to determine the location of the blocked or obscured portions of the new image by determining which pixels of the representative images have a value outside a pre-determined threshold.

14. The image processing device of claim 9, further comprising a user interface operable to allow manual adjustment of the degree of digitally merging the selected representative image with the new image.

15. The image processing device of claim 14, wherein:

the user interface is further operable to allow manually switching between a display of one or more of the representative image, the new image and the merged image; and

the processor generates signals for displaying on a display device according to the user interface.

16. A method for generating a display of an image of a patient'"'"'s internal anatomy in a surgical field during a medical procedure, comprising:

acquiring an image of the surgical field with the imaging device in a first orientation;

displaying the acquired image;

moving the imaging device, patient, or table from the first orientation;

tracking the movement of the imaging device, patient, or table from the first orientation;

moving the displayed image in relation to the tracked movement prior to acquiring a new image of the surgical field with the imaging device; and

overlaying indicia indicative of a desired movement of the displayed image.

17. The method of claim 16, wherein the indicia is a grid overlaid on the displayed image that remains stationary relative to the displayed image as the displayed images moves.

18. The method of claim 17, wherein the indicia includes a trajectory indicator indicative of the direction of view for the new image that moves with the displayed image.

19. The method of claim 18, wherein the imaging device is moved until the trajectory indicator is aligned with part of the grid prior to acquiring the new image.

20. The method of claim 16, further comprising the step of overlaying identifiers corresponding to the anatomic features in the displayed image that move with the displayed image.

21. The method of claim 16, in which the medical procedure is a surgical navigation procedure in which the position of an object, such as a tool or instrument, is tracked, wherein the new image includes an image of the tool or instrument;

and the method further comprises;

introducing a representation of the object on the acquired image;

after moving the displayed image in relation to the tracked movement, acquiring position data corresponding to the tracked position of the object and comparing the position data with the position of the object on the moved image; and

recalibrating the moved image based on the comparison of the position data with the position of the object on the moved image.

22. A method for generating a display of an image of a patient'"'"'s internal anatomy in a surgical field during a medical procedure, in which the medical procedure includes tools, instruments, implants or other objects that block or obscure the internal anatomy in an image of the surgical field, comprising:

acquiring a high resolution baseline image of anatomy within the surgical field in a baseline orientation;

digitally manipulating the high resolution baseline image to produce a baseline image set including representative images of the baseline image at a plurality of permutations of movements of the baseline image from the baseline orientation;

acquiring a new image of the surgical field in which portions of the anatomy are blocked by objects;

comparing the new image to the representative images in the baseline image set to select a representative image having an acceptable degree of correlation with the new image; and

displaying the selected representative image to show the surgical field minimizing or eliminating the blocking objects.

23. The method of claim 22, wherein the step of comparing the new image to the representative images of the baseline image set includes only comparing portions of the images outside the portions that are blocked or obscured.

24. The method of claim 23, wherein the locations of the blocked or obscured portions of the new image are determined by determining which pixels have a value outside a pre-determined threshold.