ULTRASOUND ASSISTANCE DEVICE AND METHOD, MEDICAL SYSTEM

Abstract

The invention relates ultrasound assistance device (20), an ultrasound device including such ultrasound assistance device, a medical system (100) including the same and a corresponding method as well as to a corresponding software product. According to the present invention, a segmentation of first image data (e.g. MRI data) and deformation information is obtained, while the deformation information may be obtained explicitly or implicitly (e.g. from general information of the equipment used and/or from the first image data/the segmentation of the first image data). Such deformation information is used for adjustment (e.g. automatic adjustment or guided adjustment including feedback to a user) for an adjustable ultrasound probe (30, 30′), while the ultrasound image acquired by such adjusted ultrasound probe is then segmented using the segmentation of the first image data.

Claims

1. An ultrasound assistance device, comprising: an obtaining means for obtaining a segmentation of first image data of a region of interest within a living being, the first image data being acquired by means of a probe (12) using a modality different from ultrasound, and for obtaining deformation information indicative of a first deformation caused by the probe to the living being upon acquiring the first image data, an adjustment means for determining and outputting adjustment data for an adjustable ultrasound probe such that upon acquiring ultrasound image data by means of the ultrasound probe a second deformation is provided to the living body which corresponds to the first deformation, and a segmentation means for segmenting acquired ultrasound image, using the segmentation of the first image data for initialization.

2. The ultrasound assistance device according to claim 1, wherein the obtaining means is arranged to receive the first image data and to perform a segmentation processing on the first image data for obtaining the segmentation of the first image data.

3. The ultrasound assistance device according to claim 1, wherein the obtaining means is arranged to process the segmentation and/or the first image data for obtaining the deformation information.

4. The ultrasound assistance device according to claim 1, wherein the deformation information includes information indicative of a dimension of the probe used for acquiring the first image data.

5. The ultrasound assistance device according to claim 1, wherein the outputting of the adjustment data includes at least one of outputting an adjustment value to a user of the ultrasound assistance device, determining a current adjustment of the adjustable ultrasound probe and indicating a difference between the current adjustment and an adjustment according to the determined adjustment data, and controlling the adjustable ultrasound probe according to the adjustment data.

6. The ultrasound assistance device according to claim 1, further comprising: a registration means for registering an image based on the first image data and the ultrasound image and for outputting a fusioned image based on the registration.

7. The ultrasound assistance device according to claim 1, wherein the first image data is acquired by means of Magnetic Resonance Imaging and the probe includes a MRI coil.

8. The ultrasound assistance device according to claim 1, wherein the region of interest is a prostrate, the probe is an endorectal probe and the ultrasound probe is a transrectal ultrasound probe.

9. An ultrasound device, comprising: the ultrasound assistance device according to claim 1, and an adjustable ultrasound probe.

10. The ultrasound device according to claim 9, wherein the adjustable ultrasound probe is provided with an inflatable balloon, which is fluid filled or fluid fillable, and/or one or more controllable mechanical elements acting on a flexible jacket.

11. A medical system, comprising: the ultrasound device according to claim 1, and a Magnetic Resonance Imaging device, wherein the Magnetic Resonance Imaging device comprises a probe including an MRI coil and is arranged to provide Magnetic Resonance Imaging data to the obtaining means of the ultrasound assistance device.

12. An ultrasound assistance method, comprising the steps of: obtaining a segmentation of first image data of a region of interest within a living being, the first image data being acquired by means of a probe using a modality different from ultrasound, obtaining deformation information indicative of a first deformation caused by the probe to the living being upon acquiring the first image data, determining adjustment data for an adjustable ultrasound probe such that upon acquiring ultrasound image data by means of the ultrasound probe a second deformation is provided to the living body which corresponds to the first deformation, outputting the adjustment data, and segmenting acquired ultrasound image, using the segmentation of the first image data for initialization.

13. A software product for ultrasound assistance, the software product comprising program code means for causing an ultrasound assistance device to carry out the steps of the method as claimed in claim 12 when the software product is run on the ultrasound assistance device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In the following drawings:

[0045] FIG. 1 schematically shows a medical system in accordance with an embodiment of the invention,

[0046] FIG. 2 schematically shows an MR imaging coil and two adjustable ultrasound probes in accordance with embodiments of the invention,

[0047] FIG. 3 shows an illustration of image-based determination of an endorectal coil width, and

[0048] FIG. 4 shows a flow diagram illustrating a method according to an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0049] FIG. 1 schematically shows a medical system in accordance with an embodiment of the invention.

[0050] The medical system 100 according to the present embodiment includes a MR imaging system 10, an ultrasound device including an ultrasound assistance device 20 and an adjustable ultrasound probe 30.

[0051] The ultrasound assistance device 20 includes an obtaining unit 22, an adjustment unit 24, a segmentation unit 26 and a registering unit 28.

[0052] The MR imaging system 10 is configured to image a prostate with an endorectal coil (ERC) (see FIG. 2 a)).

The ultrasound probe 30 is adjustable, such that it can assume an imaging geometry and form factor that allows prostate ultrasound image acquisition with basically the same deformations to the prostate as during MRI imaging.

[0053] A workflow implemented by the medical system 100 includes that the MR imaging system 10 images the prostate using MRI with the ERC. Further, the prostate is segmented by the MR imaging system 10 in the MR image.

[0054] Later, the ultrasound device is arranged to image the prostate with the ultrasound probe 30 that has—due to the adjustment—basically the same form factor as the ERC.

[0055] The ultrasound assistance device 20 and more specifically the segmentation unit 26 further maps the MRI segmentation on the ultrasound image to initialize ultrasound segmentation and automatically segments the prostate in the US image, based on the MRI initialization.

[0056] Furthermore, the ultrasound assistance device 20 and more specifically the registering unit 28 registers the MR and ultrasound images based on the segmentations and uses the registered MRI/US images to perform fusion imaging or fusion biopsy guidance.

[0057] FIG. 2 schematically shows an MR imaging coil and two adjustable ultrasound probe in accordance with embodiments of the invention.

[0058] FIG. 2 a) illustrates a conventionally known endorectal probe 12 including an MR coil. The probe has a diameter d which is larger than diameters of typically known ultrasound probes for prostate applications. As such endorectal MR probe is well known to the skilled person, no further discussion is provided.

[0059] FIG. 2 b) illustrates an adjustable ultrasound probe 30 in accordance with an embodiment of the invention. The probe 30 includes an ultrasound imaging array 32 and is further provided, on the side opposite to the imaging array 32 (i.e. facing away from the imaging direction), with a flexible jacket 34, which is deformed by wings 36 of the probe 30, wherein the diameter of the probe 30 may thus be adjusted.

[0060] FIG. 2 c)) illustrates another adjustable ultrasound probe 30′ in accordance with an embodiment of the invention. The adjustable probe 30′ also includes an ultrasound imaging array 32′, while, however, the distal portion (i.e. the illustrated portion) is enclosed by an adjustable balloon 34′ filled with fluid 38. By adjusting the amount of fluid 38 provided inside the balloon 34′, the diameter thereof may be adjusted. As such, such adjustable ultrasound probe including a balloon is known, and therefore no further explanation thereof might be needed.

[0061] According to the present invention, the adjustable ultrasound probe is provided such that—in operation—the active tip containing the imaging array has the same diameter d as the endorectal MR imaging coil used during MR imaging. During ultrasound scanning, the contact of the US imaging probe with the tissue will thus give rise to the same/similar tissue deformation as during MR imaging. In order to accommodate MR images obtained with coils of variable width d, an ultrasound probe can, for example, be fitted with a fluid-filled or fluid-fillable balloon that can be inflated to the same width d as the MR imaging coil.

[0062] The balloon width can be calibrated with respect to the fluid fill volume, giving the width d as a function of the injected fluid volume. Based on the MR coil width used, the user can inject the desired fluid volume to reach width d.

[0063] FIG. 3 shows an illustration of image-based determination of an endorectal coil width. From FIG. 3, one can see that it is possible to determine the diameter of the probe used by fitting a circle to the dark area resulting from the probe.

[0064] FIG. 4 shows a flow diagram illustrating a method according to an embodiment of the present invention.

[0065] The method starts in this case with an obtaining (51) of a segmentation of first image data of a region of interest within a living being, wherein the first image data was previously acquired by means of an MRI probe (endorectal coil).

[0066] Further, the method includes obtaining (52) deformation information indicative of a first deformation caused by the probe to the living being upon acquiring the first image data.

[0067] Based on the deformation information, the method further includes determining (53) adjustment data for an adjustable ultrasound probe such that upon acquiring ultrasound image data by means of the ultrasound probe a second deformation is provided to the living body which corresponds to the first deformation.

[0068] The adjustment data is then used for controlling (54) the adjustable ultrasound probe.

[0069] An ultrasound image acquired using the adjusted ultrasound probe is then segmented (55), using the segmentation of the first image data for initialization.

[0070] Furthermore, a fusioned image is generated or registered (56) based on the first image data and the ultrasound image and the fusioned image is then outputted (57).

[0071] For accurate fusion imaging and other clinical tasks such as determination of prostate volume it is desirable to segment a 3-dimension ultrasound (3DUS) image of the prostate. The shape and thus the segmentation of the prostate depends on the deformation on the prostate introduced by the ultrasound probe. A workflow including an obtaining of a 3D MRI can with an endorectal coil (ERC), an obtaining of a prostrate segmentation in the 3D MRI, an obtaining of a 3DUS scan with an ultrasound probe that is matched in size to the ERC, a mapping of the MRI segmentation on the 3DUS so to initialize automatic 3DUS segmentation and an adjusting of the segmentation to fit the prostate contours in the 3DUS can be used to extract the ultrasound segmentation accurately and robustly, based on a segmentation already performed on the prior MRI volume.

[0072] While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments.

[0073] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

[0074] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality.

[0075] A single processor, device or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0076] Operations like segmenting, calculating, determining, outputting, processing and the like can be implemented as program code means of a computer program and/or as dedicated hardware.

[0077] A computer program may be stored and/or distributed on a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

[0078] Any reference signs in the claims should not be construed as limiting the scope.