APPARATUS AND METHOD FOR REGISTERING LIVE AND SCAN IMAGES

Abstract

The disclosed system uses medical imaging and live imaging on a patient’s non-rigid tissue structures and increases preciseness and reliability by shaping the patient’s body during surgery so that the outer shape of the patient’s body during surgery is identical to the outer shape of the body during imaging. The processing unit will precisely overlay a scan image (or an image or a graphical representation derived from several scan images) and a live image acquired during surgery for enhancing a surgeon’s understanding and orientation during surgery.

Claims

1. An arrangement for imaging (10) and surgery (34) on a patient’s body (18) comprising: a patient support device (11) adaptive to a shape of the patient’s body, at least one tracker element (21) connected to the support device (11) and adapted to indicate a position and orientation of the patient support device (11), means for capturing data (33) indicating a position and/or orientation of the at least one tracker element (21), a medical imaging system (13) adapted to acquire at least one at least 2-dimensional scan image (29) of a patient’s region of interest in relation to the position of the at least one tracker element (21), a detection system (35) for capturing data (36) indicating the at least one tracker element’s position during surgery, a live imaging device (39) for acquiring live images (42) of an operation site, and a processing unit (28, 28a) adapted to register and blend the at least one at least 2-dimensional scan image and the live images (29, 42, 52) according to the data captured during the medical imaging and live imaging.

2. The arrangement of claim 1, wherein the patient support device (11) includes a movable table (14, 14a).

3. The arrangement of claim 1, wherein the patient support device (11) is adaptive to the shape of the patient’s body by 3D-printing at least one element (15) according to a scan of at least a part of an outer shape of the patient’s body.

4. The arrangement of claim 1, wherein the patient support device (11) comprises at least one deformable element (15) of a malleable material (15a), and wherein the malleable material is a curable material (15a).

5. The arrangement of claim 4, wherein at least one tracker element (21) is directly connected to the at least one deformable element (15).

6. The arrangement of claim 4, wherein the at least one deformable element (15) is open at one side, so that the patient can be removed from and reinserted into the at least one deformable element (15).

7. The arrangement of claim 1, wherein the support device comprises at least two deformable elements (15, 16, 17) embracing at least a portion of the patient.

8. The arrangement according to claim 6, wherein the at least one deformable element (15, 16, 17) comprises a window (49) for giving access to the patient.

9. The arrangement of claim 1, comprising an instrument (44) for treating the patient’s body (18) in the region of interest (41).

10. The arrangement of claim 1, wherein the at least one tracker element (21) is adapted to indicate the position and the orientation of the support device in space.

11. The arrangement of claim 1, wherein the at least one tracker element (21) comprises spaced apart reflector elements detectable by the detection system.

12. The arrangement of claim 1, wherein the detection system comprises at least two cameras (37, 38) for trigonometrically determining the position and the orientation of the at least one tracker element (21) in space.

13. The arrangement of claim 1, wherein the live imaging device comprises at least one camera (39).

14. The arrangement of claim 13, further comprising a detection system (35) for detecting a location and orientation of the at least one camera (39) of the live imaging device.

15. A method for image registering, the method comprising: adapting a patient support device (11) to a shape of a patient’s body (18), connecting at least one tracker element (21) to the patient support device (11) and capturing data indicating a position and/or orientation of the at least one tracker element (21), acquiring at least one at least 2-dimensional scan image (29) of a patient’s region of interest (41) in relation to the position of the at least one tracker element (21) with a medical imaging system (13), capturing data (36) indicating the at least one trackerelement’s position during surgery by means of a detection system (35), acquiring live images (42) of an operation site by a live imaging device (39), and registering and blending the at least one at least 2-dimensional scan image and the live images according to the data (36) captured during the medical imaging and live imaging.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is a schematic representation of a patient support device with a patient placed thereon and a medical imaging device,

[0028] FIG. 2 is a cross-sectional view of the patient support device and the patient placed thereon,

[0029] FIG. 3 is a schematic representation of scan image provided by the medical imaging device,

[0030] FIG. 4 is the patient according to FIG. 1 placed on a patient support device at the operation site of the inventive arrangement, including a localization or detection system for localizing or detecting the patient during surgery,

[0031] FIG. 5 illustrates a scan image, a live image and blended image provided to the surgeon,

[0032] FIG. 6 is a schematic representation of the camera for acquiring live images, and

[0033] FIG. 7 illustrates the scan images, a volume model of a patient’s tissue structure obtained from the scan images, and the live image registered into the spatial representation of the tissue structure.

DETAILED DESCRIPTION

[0034] FIG. 1 illustrates an arrangement for medical imaging 10, comprising a support device 11 for positioning a patient 12 in a desired position relative to a medical imaging system 13. The support device 11 may consist of a table 14 and at least one deformable element 15 placed thereon. Further deformable elements 16 and 17 may be placed around the patient’s 12 body 18 as can be taken from FIG. 2 illustrating a cross-sectional view of the table 14, the deformable elements 15 to 17, and the body 18.

[0035] The deformable elements 15 to 17 may be cushions filled with malleable durable material as there is plaster cast, fiber glass, reinforced plaster cast, resin-based casts or the like. Alternatively the malleable material may be directly placed on the skin of the patient or at a cloth lying on the skin. While the deformable element 15 may be placed between the body 18 of the patient 12 and the table 14 elements 16 and 17 may be placed on the patient 12 and e.g. held between walls 19, 20. At least one of the deformable elements 15 to 17 and/or at least one of the walls 19 is firmly connected to tracker elements 21, 22, 23, which in the present case are balls fixed at the ends of a tree 24 in known distances one from another. Balls 21 to 23 may be light-reflecting or light-absorbing balls visible by the imaging system 13 or a specific camera assigned to the imaging system 13. In the present case three tracking elements are provided for unambiguously indicating the location and orientation of the patient 12. However, while three balls 21, 22, 23 placed on the ends of a tree give a fairly good indication of the location and orientation of the patient 12, it is also possible to place at least three different balls independent one from another at different places of the deformable element 15, 16 or 17. If the tracker elements 21, 22, 23 will be optically detected they will be placed at a visible side of the deformable elements 15 to 17.

[0036] Furthermore, it is possible to use only one item as a tracker element, e.g. one cube firmly connected to the support 14 or at least one of the deformable elements 15, 16 and 17.

[0037] The imaging system 13 can be any type of medical imaging systems for acquiring a pre-operative medical scan as there is a MRI-system or a CT system as illustrated in FIG. 1. The CT system may comprise an X-ray source and an X-ray detector adapted to receive X-ray from source and deliver data to a processing unit 28 producing scan images 29 (29a to 29z) as illustrated in FIG. 3. The processing unit 28 may be any type of computer adapted to process signals supplied by the X-ray detector 27. The processing unit 28 is connected to a storage 30 for storing the scan images 29 therein. Alternatively or additionally an intraoperative scan apparatus may be provided, e.g. a C-Arm system, an ultrasonic imaging apparatus or any other system suited for providing medical scan images during operation.

[0038] The medical imaging system 13 may additionally be used as a means for capturing data 33 indicating the positions of the tracking elements 21, 22, 23 during operation of the imaging system i.e. during the scanning of the patient’s body 18. Alternatively a separate localization or detection system may be provided for detecting and locating the tracking elements 21, 22, 23 and bringing the images 29 into spatial relation to the tracking elements 21, 22, 23.

[0039] Part of the inventive arrangement 10 is an operation site 34 illustrated in FIG. 4. The patient 12 again is placed on a table 14a, which may be identical with the table 14 of the imaging site illustrated in FIG. 1. However, typically table 14a will be a different table as typically used in a regular operating room. No matter whether the tables 14, 14a are identical or not, in any case the deformable elements 15 to 17 will be used for presenting the patient’s body 18 in the same shape as it has had during medical imaging when illustrated in FIG. 2. Moreover the tracking elements 21, 22, 23 will be in the same position relative to the patient’s body 18 during imaging and during surgery as well.

[0040] At the operation site 34 a localization or detection system 35 is provided for capturing data 36 fed to a processing unit 28a connected to storage 30. The processing unit 28a may be identical with processing unit 28 of FIG. 1 or alternatively it may be a different processing unit. Processing unit 28a may be any type of computer or processor adapted to receive data from the detection system 35 and determine the position and orientation of the tracker elements 21, 22, 23 and hence the position and orientation of the patient’s 12 body 18. The detection system 35 may comprise at least two cameras 37, 38 oriented such that the tracking elements 21, 22, 23 are within the field of view of the cameras 37, 38. The processing unit 28 or 28a is adapted to locate the tracker elements 21, 22, 23 by triangulation once before the surgery starts if the table 14a is kept at rest. If table 14a is moved the detection system 35 may repeat determining the position and orientation of the patient’s 12 body 18. Alternatively, the detection may be done permanently by the detection system 35.

[0041] Part of the arrangement is another camera 39 for acquiring live images as separately illustrated in FIGS. 4 and 6. The field of view 40 of the camera 39 is a region of interest 41 of the patient’s body 18 at which a surgery is to be performed. FIG. 5 illustrates region of interest 41 covered by the field of view 40. The camera 39 may be a laparoscopic camera, and endoscopic camera or any other type of camera suitable and adapted to produce a live image 42 of the region of interest 40.

[0042] The live image 42 may be fed to the processing unit 28 or 28a as illustrated in FIG. 4. The processing unit 28a may process any live image 42 which is shown in FIG. 5, right upper illustration. The Live image 42 may contain a real tissue structure 43 and the tip of an instrument 44.

[0043] Any type of detection system may be used for detecting location and orientation of the instrument 44 and/or the camera 39. The detection system 35 may involve a tracker structure 45 connected to the camera 39 and visible by the cameras 37, 38. The tracker structure may comprise at least one tracker element, e.g. three tracker elements 46, 47, 48 as illustrated in FIG. 6, similar to the tracker elements 21, 22, 23. Other types of tracking systems may be used.

The so Far Described Arrangement 10 Operates as Follows

[0044] Before surgery the patient 12 will be placed on the support 11 device at the table 14 with the deformable element 15 shaped by the body 18 as illustrated in FIG. 2. If desired or necessary, one or two further deformable elements 16, 17 will be placed around the patient’s body 18 so that the deformable elements 15, 16, 17 assume the negative shape of the patient’s body 18 and fit closely around the body 18. The deformable elements 15, 16, 17 are filled with or formed by malleable material which will solidify over time, e.g. within some minutes or some tens of minutes. After curing i.e., solidifying the imaging system 13 may acquire scan images 29a through 29z, which images are stored by processing unit 28 in the storage 30. Afterwards the patient 12 may leave the support device 11 and prepare for surgery, which may follow within short and sometimes after hours or days.

[0045] For surgery the patient 12 reenters the support device 11 as illustrated in FIG. 4 by placing his or her body 18 at the table 14a with the once deformable and now rigid element 15 to 17, placed around the body 18 as illustrated in FIG. 2. The surgeon may have cut-out a window 49 in one or more of the elements 15, 16, 17 so that he or she has access to the body 18 through window 49. The window 49 may also be provided in the support device, in particular in the deformable element(s) 15, 16, 17 for planned operation before the patient is placed in the deformable element. Alternatively the window 49 may be cut into the deformable element(s) 15, 16, 17 between the medical pre-operative scan and the surgery. This process may be part of planning the operation.

[0046] At the beginning or before the beginning of the surgery the detection system 35 will be activated, which captures the positions of the tracking elements 21, 22, 23. So the processing unit 28a may register the position of the patient’s body 18 to the scan images 29a to 29z as illustrated in FIG. 7. Moreover, the processing unit 28a or the processing unit 28 may produce a volume model 50 of at least a portion of the patient’s body, e.g. of the region of interest 41.

[0047] The detection system 35 or any other tracking system for determining the position and orientation of the camera 39 continuously produces data from which the processing unit 28a determines the place and orientation of the field of view 40 of the camera 39 and hence the place of the live image 42 and the viewing direction to the live image. As illustrated in FIG. 7, the live image 42 may intersect the volume model 50 in a different way as do the scan images 29a to 29z. However, the processing unit 28a may produce a synthetic image of the volume model 50 as illustrated in FIG. 5 upper left illustration at least of the region of interest 41. For doing so the processing unit may intersect the volume model 50 in the same plane as the live image.

[0048] The processing unit 28a will then merge or blend the live image 42 (FIG. 5 upper right illustration) with the volume model illustration derived by intersecting the volume model 50 at the same place and with the same orientation as has the live image 42. FIG. 5 illustrates the blended image 51 with the tissue structures 43 seen by camera 39 and a specific tissue structure 52 found by the imaging and to be treated by instrument 44.

[0049] Furthermore the processing unit 28 or 28a may alternatively or additionally produce graphic representations 52 of tissue structures and blend those graphic representations into the live image. Any of the scan images 29, the image obtained by intersecting the volume model 50, and graphic representation 52 obtained from at least one of the scan images or from the volume model 50 are considered being “a scan image” for blending with the “live image” according to claim 1. The arrangement 10 further comprises an image display 53 for reproducing the blended image. The display 53 may be a screen, a virtual reality headset or any other means for showing the blended image.

[0050] The inventive system uses medical imaging and live imaging on a patient’s non-rigid tissue structures and increases preciseness and reliability by shaping the patient’s body 18 during surgery so that the outer shape of the patient’s body during surgery is identical to the outer shape of the body during imaging. The processing unit 28 or 28a will precisely overlay a scan image (or an image or a graphical representation derived from several scan images) and a live image acquired during surgery for enhancing surgeons understanding and orientation during surgery.

[0051] Reference Numerals: [0052] 10 Arrangement for medical imaging [0053] 11 Support device [0054] 12 Patient [0055] 13 Imaging system [0056] 14, 14a Table [0057] 15 - 17 Deformable element [0058] 15a - 17a Malleable / curable material [0059] 18 Patient’s body [0060] 19, 20 Walls [0061] 21 - 23 Tracker elements [0062] 24 Tree [0063] 28, 28a Processing unit [0064] 29 Scan images [0065] 30 Storage [0066] 33 Means for capturing data [0067] 34 Operation site [0068] 35 Localization or detection system [0069] 36 Data [0070] 37, 38 Cameras [0071] 39 Camera [0072] 40 Field of view of camera 39 [0073] 41 Region of interest [0074] 42 Live image [0075] 43 Tissue structure [0076] 44 Instrument [0077] 45 Tracker structure [0078] 46 - 48 Tracker elements [0079] 49 Window [0080] 50 Volume model [0081] 51 Blended image [0082] 52 Tissue structure [0083] 53 Display