Abstract
A device (1) and method to treat a patient (P) with High-Intensity Focused Ultrasound (HIFU), wherein the device (1) performs a movement of an imaging device (4) along a longitudinal axis (8a, 8b) while acquiring images.
Claims
1-33. (canceled)
34. A device for treatment of a patient by HIFU, the device comprising a treatment head including a unit for emission of HIFU pulses, an imaging device having a probe a control unit for controlling the movement of the probe wherein the control unit is adapted to carry out a movement of the probe with respect to a target (T) during operation of the imaging device.
35. The device according to claim 34, wherein the control unit is adapted to allow a user-controlled movement and/or to carry out a movement of the probe which approximately follows one of the following axes: axis orthogonal to the current imaging plane axis parallel to the main axis of the target projection of the main target axis in a plane orthogonal to the main ultrasound propagation axis projection of the main target axis in a plane parallel to the skin surface.
36. The device according to claim 35, wherein the control unit is adapted to store at least one reference position in a memory, and wherein the control unit is further adapted to trigger a movement of the probe to the reference position.
37. The device according to claim 34, wherein the control unit is adapted to carry out a movement of the probe away from an initial position at a first speed, followed by a return.
38. The device according to claim 34, wherein the device comprises a user interface to trigger a movement of the probe away from the current position.
39. The device according to claim 38, wherein the user interface comprises at least one actuator to trigger a movement of the probe away.
40. The device according to claim 38, wherein the user interface comprises two buttons to trigger a movement of the probe, one for each direction along a chosen axis.
41. The device according to claim 38, where the at least one button is selected from the group of a physical or virtual button.
42. The device according to claim 34, wherein the control unit is adapted to carry out an oscillatory movement of the probe roughly along one of the aforementioned axes.
43. The device according to claim 42, wherein the control unit is adapted to carry out an oscillatory movement selected from the group of one or a predefined number of oscillations around an initial position a finite number of damped oscillations around a current position continuous oscillations around an initial position until a predetermined criterion is fulfilled.
44. The device according to claim 43, wherein the control unit is adapted to carry out an oscillatory movement with an amplitude greater than 1 mm.
45. The device according to claim 34, wherein the control unit is adapted to carry out a movement along an at least partially curved trajectory.
46. The device according to claim 45, comprising at least one of an input interface for definition of the trajectory by the user and a calculation unit for automatically computing the trajectory.
47. The device according to claim 34, wherein the control unit is adapted to carry out the movement by a control representing the coordinates of the probe.
48. The device according to claim 34, comprising a range limiter for limiting the movement of the probe.
49. The device according to claim 48, wherein the range limiter is defined by mechanical limits of a holding arrangement for holding the probe or definable through a user interface.
50. The device according to claim 34, wherein the device is adapted to associate the collected images to a coordinate along the trajectory and wherein the device comprises a display adapted to display the image corresponding to a given coordinate.
51. The device according to claim 50 wherein the display comprises a shared area for displaying the acquired images and for are for display of an image of the zone where a sonication has to be delivered, whereby a. when the virtual position of the probe is set at the actual position of the probe, the live image of the zone where a sonication has to be delivered is displayed b. when the virtual position of the probe is set it at another position, the corresponding image from the set of acquired images is displayed.
52. The device according to claim 34, wherein the navigation control is monostable so that, when it is released, the virtual position of the probe goes back to the actual position of the probe.
53. A method of preparing a treatment of a patient with HIFU, comprising the steps: Performing a movement with a treatment head away from a target site Acquiring at least one image away from the target site Defining the position of a target in the vicinity of the target site based on the at least one acquired image Performing a movement of the treatment head to the target site
54. A method of preparing a treatment of a patient with HIFU, comprising the acquisition of a collection of 2D prior to or during treatment, wherein the image acquisition comprises the following steps Positioning a treatment head on the patient Defining a longitudinal direction, wherein this direction, Performing an automatic controlled movement along the longitudinal axis to acquire a set of images.
Description
[0101] In the following, the invention is described in detail with reference to the following figures, which show:
[0102] FIG. 1: a schematic representation of the device according to the present invention
[0103] FIG. 2: a schematic representation of the method carried out with the present invention
[0104] FIG. 3: an example of a display with a set of acquired images and a live view.
[0105] FIG. 4: an example of a user interface.
[0106] FIG. 5: a schematic illustration of a rotational movement.
[0107] FIG. 6: a schematic illustration of a user interface with saved reference positions.
[0108] FIGS. 7a-7d: a schematic movement away from a reference position and back to a corrected reference position.
[0109] FIG. 1 shows schematically a device 1 according to the invention to treat a patient with HIFU. The device 1 comprises a treatment head 2 with a unit to emit HIFU pulses, here in the form of a transducer 3. The transducer 3 is adapted to deliver HIFU pulses onto a target T in an object O. In the present embodiment, the treatment head 2 further comprises an imaging device 4. The treatment head further comprises a balloon 5 for receiving a fluid for acoustic coupling. Here, the device further comprises a movement device 6 that is connected to the treatment head 2 by an arm 7 and that is adapted to move the treatment head 2 along a longitudinal axis 8a, 8b. In particular, the movement device can be controlled to perform dynamic movements such as oscillations or movement with varying speeds. In the present embodiment, the movement device 6 also comprises a mechanical range limiter 9a, 9b. The range limiters, which could also be embodied as electronic or software-based limiters, limit the accessible range of the treatment head in order to prevent damage to the patient or the device. The device also comprises a controller unit 10 that is operatively connected to the transducer 2 and the movement device 6, in the present example by means of a cable 11.
[0110] FIG. 2 schematically shows how the method according to the invention works. A treatment head 2 comprising a balloon 2 is used to treat a target in an object O. Here, the method is carried out before the treatment of a patient. However, it is also possible to conduct the same method during a treatment. First, a longitudinal axis 8a is defined. Here, the longitudinal axis corresponds to the main propagation direction of the HIFU pulses, however, another axis, for example orthogonally to the main ultrasound propagation axis 8b, could be chosen as well. Using a movement device (not shown) that is operatively connected to the treatment head via an arm 7, the treatment head 2 is moved along the longitudinal axis 8a, 8b while operating an imaging device (not shown) integrated in the treatment head. The imaging device records several images 12a, 12b, 12c, 12d, 12e at different locations that correspond to different points along the longitudinal axis 8a, 8b. Here, the target within the object O is visible only on some of the collected images. On the images 12b and 12d, the target T is visible as representation 13c and 13a. On image 12c, the target T is only partially visible 13b. The collected images can later be accessed by the operator and used to locate the target. Alternatively, the same images could also be collected during treatment if the target T becomes invisible in the ultrasound image.
[0111] FIG. 3 shows an example of a user interface 39 with a set of acquired images 31. The user intends to perform a sonication in the slice displayed in the live view 34. In this slice, the precise position, symbolized by arrows 33, of the vein is difficult to determine. Therefore, the user scrolls within the spatial cine-loop 1 with the slider 32 to a neighbouring position where the vein clearly can be seen. Finally, the user mentally follows the vein as when scrolling back to the slice where a sonication is to be performed.
[0112] FIG. 4 shows an illustration of a possible user interface 39. In this example, the treatment head has been moved laterally after the acquisition. Thus, the images of the set of acquired images 31 have been shifted, which results in the yellow area 40, where no information is available for display. In this example, a button 36 enables to place a marker 35 on the images of the set of acquired images 1. As the two images are spatially consistent due to the shifting, the marker 35 is simply displayed in the live view 34 at the same position in the image. In this example, a button to hide the marker 38 is added to the interface. This allows for better visualization since markers, although helpful, may hinder visibility of the anatomical structures. In addition, a user may delete a marker with a third button 37.
[0113] FIG. 5 shows schematically a rotational movement of the treatment head 2. Initially, the treatment head oriented at a target T in a patient's body (not shown). The focal spot 16 of the HIFU beam 15 is positioned at a site that is to be treated. However, from that particular angle, the target may not be very well visible. Thus, the treatment head is rotated 17 around and axis 14 that intersects with the focal spot 16. Because the focal spot lies on the rotational axis, it does not move. The treatment head 2 and the HIFU beam 15 rotate around the axis such that the orientation remains the same and toward the axis 14.
[0114] FIG. 6 schematically shows an embodiment of the working principle of reference positions. A user may have saved several reference positions along a vein (not shown). The user interface is adapted to display several lines 19, each representing a reference position along the direction 20 of the vein. Additionally, the user interface also displays the position of the treatment head. However, at that position, the vein may not be visible. Thus, the user clicks on a position 18 where he wishes to view the vein. The device automatically calculates which reference position 19 is closest to the position 18 the user clicked on. The treatment head 2 is then moved to that position. The user can then examine the vein because of its increased visibility at the new position. He may then choose to move back by clicking in the vicinity of the treatment position 21. The device calculates the closest reference position, which in this case is the treatment position, and moves the treatment head there.
[0115] FIGS. 7a-7d show schematically a movement of the treatment head (not shown).
[0116] FIG. 7a shows the focus point 100 of an ultrasonic treatment head (not shown) in tissue 101. A target T is located in the tissue 101 and not visible in the ultrasonic image at the shown arrangement of the focal spot 100. The focus point 100 is displaced from the target T by a distance 102. However, the user cannot be aware of the displacement 102 due to the lack of visibility of the target T. The image taken by the treatment head in FIG. 7a is a cross-section in a first plane P1. In order to make the target T visible, the treatment head is moved from a first position along a longitudinal axis of the target T (i.e. along an axis perpendicular to the plane of the drawing shown here) to a second position such as to image a cross-section in a plane P2 (see FIG. 7b).
[0117] FIG. 7b shows the recorded image in the plane P2. Plane P2 is parallel to plane P1 of FIG. 7a, but displaced along the longitudinal axis of the target T. In plane P2, the target T is visible. Therefore, the user can see that the focus point 100 is laterally displaced by distance 102 from the target T.
[0118] As shown in FIG. 7c, the user thus moves the treatment head such as to position the focus point in 100 onto the target in plane P2 by laterally displacing the treatment head. Here, the user performs this movement manually and positions the treatment head such that the focus 100 falls onto the target T. Alternatively, however, it would also be possible to automatically move the treatment head or only measure the distance 102 for calculation of a corrected reference position (see FIG. 7d).
[0119] FIG. 7d shows the focus point 100 that has been moved back along the longitudinal axis of the target T to a corrected reference position. Here, the corrected reference position refers to a position at the same position along the longitudinal axis of the target T, but displaced in a direction parallel to the planes P1, P2 by a distance 102 that corresponds to the displacement between the target T and the focus 100 in FIG. 7a. Therefore, the focus point 100 in FIG. 7d is located on the target T which is not visible in plane P1.
[0120] The person skilled in the art will note that the planes P1 and P2 correspond to an identical treatment orientation, i.e. the treatment head is oriented identically with respect to the target in the FIGS. 7a-7d. Therefore, the reference position and the corrected reference position are defined with respect to the same treatment orientation (i.e. the planes P1 and P2 remain parallel).
