ULTRASOUND DEVICE

Abstract

An ultrasound treatment device (1) which comprises a probe head (2) that comprises an ultrasound transducer (3) and an imaging device (4), a deformable coupling balloon (5) with a cavity (6), between the probe head (2) and the coupling balloon (5) filled with a coupling liquid (7), a pressure sensor (9) for determining the pressure of the coupling liquid (7) in the cavity (6), a fluid control system (10), and a controller unit (13). The device (1) is adapted to switch between at least first and second operating modes (I, II). In the first operating mode (I), the pressure of the coupling liquid (7) is maintained at a first pressure value (P1), and, in the second operating mode (II), the pressure of the coupling liquid (7) is maintained to a second pressure value (P2) which is higher than the first pressure value (P1).

Claims

1-24. (canceled)

25. An ultrasound treatment device, the ultrasound treatment device comprising: a probe head comprising an ultrasound transducer for delivering treatment ultrasound waves focused onto a target within an object, a compression unit for applying a compression force to the object, and a controller unit connected at least to the probe head and the compression unit, wherein the ultrasound treatment device is adapted to switch between at least two operating modes, and in a first operating mode, the compression force applied to the object by the compression unit is maintained at a first compression force value, and in a second operating mode, the compression force applied to the object by the compression unit is maintained at a second compression force value.

26. The ultrasound treatment device according to claim 25, wherein the probe head comprises an imaging device for imaging of the object.

27. The ultrasound treatment device according to claim 26, wherein in the first operating mode the controller unit controls the imaging device to perform imaging of the object, and in the second operating mode the controller unit controls the ultrasound transducer to emit at least one pulse of treatment ultrasound waves.

28. The ultrasound treatment device according to claim 25, wherein the ultrasound treatment device comprises: a deformable coupling balloon arranged at a target side of the probe head, wherein a cavity between the probe head and the coupling balloon is filled or fillable with a coupling liquid, a pressure measuring unit for determining the pressure of the coupling liquid in the cavity, a fluid control system for controlling the pressure or the volume of the coupling liquid in the cavity, wherein the controller unit is connected at least to the pressure measuring unit, the fluid control system, the probe head and the compression unit, and in the first operating mode, the pressure of the coupling liquid is maintained at a first pressure value or at a first volume value, and in the second operating mode, the pressure of the coupling liquid is maintained at a second pressure value higher than the first pressure value or the volume of the liquid in the cavity is maintained constant at a second volume value.

29. The ultrasound treatment device according to claim 28, wherein the controller unit is adapted to: monitor the pressure of the coupling liquid determined by the at least one pressure measurement unit and to detect an increase of the pressure of the coupling liquid in the cavity when the ultrasound treatment device is in the first operating mode and the coupling balloon is arranged on the object, switch from the first operating mode to the second operating mode upon detection of a switching signal, trigger the emission of at least one pulse of treatment ultrasound waves after switching from the first operating mode to the second operating mode, and switch from the second operating mode to the first operating mode after the emission of at least one pulse of treatment ultrasound waves.

30. The ultrasound treatment device according to claim 25, wherein the ultrasound treatment device further comprises a manual switch for switching from the first operating mode to the second operating mode.

31. The ultrasound treatment device according to claim 28, wherein the controller unit is further adapted to switch from the first operating mode to the second operating mode when the detected pressure increase is above a threshold value.

32. The ultrasound treatment device according to claim 28, wherein the controller unit is further adapted to switch from the first operating mode to the second operating mode when the detected pressure increase is above a threshold value and then below a second threshold value.

33. The ultrasound treatment device according to claim 28, wherein the controller unit is further adapted to switch from the second operating mode to the first operating mode when a detected pressure decrease is below a threshold value (TS3).

34. The ultrasound treatment device according to claim 25, wherein the ultrasound treatment device further comprises at least one force sensor, connected to the controller unit, and the controller unit is further adapted to compare a force determined by the force sensor with a threshold value and to switch the ultrasound treatment device in the second operating mode when the force determined by the force sensor is above the threshold value.

35. The ultrasound treatment device according to claim 34, wherein the controller unit is further adapted to switch from the second operating mode to the first operating mode after the emission of at least one pulse of treatment ultrasound waves when the force determined by the force sensor is below a second threshold value.

36. The ultrasound treatment device according to claim 25, wherein the controller unit is further adapted to automatically trigger the emission of at least one pulse of treatment ultrasound waves after activation of the second operating mode.

37. The ultrasound treatment device according to claim 25, wherein the ultrasound treatment device further comprises a manual switch for triggering the emission of at least one pulse of treatment ultrasound waves by an operator, and switching from the first operating mode to the second operating mode is performed automatically after triggering the emission of at least one pulse of treatment ultrasound waves.

38. The ultrasound treatment device according to claim 37, wherein the ultrasound treatment device further comprises time measuring means for delaying the emission of at least one pulse of treatment ultrasound waves by a predetermined amount of time after the second operating mode is activated.

39. The ultrasound treatment device according to claim 38, wherein the time measuring means are further adapted to automatically switch from the second operating mode to the first operating mode with a delay of a predetermined amount of time after emission of the treatment ultrasound waves.

40. The ultrasound treatment device according to claim 26, wherein the controller unit is adapted to determine a position of the target based on the images captured by the imaging device and to switch to the second operating mode automatically when the position of the target is stable over a predetermined amount of time.

41. The ultrasound treatment device according to claim 25, wherein the ultrasound treatment device is further adapted to switch to a third operating mode, and in the third operating mode the compression force applied to the object by the compression unit is maintained at a third compression force value, or the volume of the liquid in the cavity is maintained to a third volume value.

42. A method for treating a target within an object with an ultrasound device, the method comprising the following steps: placing a probe head comprising an ultrasound transducer for delivering treatment ultrasound waves focused onto a target within an object on the object and applying a first compression force on the object; applying a second compression force value higher than the first compression force value, either manually by an operator or by means of a compression unit of the device, and emitting at least one pulse of treatment ultrasound waves.

43. The method according to claim 42, wherein the probe head comprises an imaging device for imaging of the object.

44. The method according to claim 43, wherein imaging of the object by means of the imaging device while applying the first compression force to the object is performed.

45. The method according to claim 42, the method comprising the following steps: a) placing a deformable coupling balloon arranged at a target side of the probe head, wherein a cavity between the probe head and the coupling balloon is filled with a coupling liquid onto the object and activating a first operating mode where the pressure of the coupling liquid is maintained at a first pressure value or the volume of the coupling liquid in the cavity is maintained at a first volume value, b) switching from the first operating mode to a second operating mode, wherein in the second operating mode the pressure of the coupling liquid is maintained at a second pressure value which is higher than the first pressure value or the volume of the coupling liquid in the cavity is maintained at a second volume value.

46. The method according to claim 45, wherein switching from the first operating mode to the second operating mode is performed upon detection of a switching signal.

47. The method according to claim 46, further comprising the step of monitoring the pressure of the coupling liquid by means of a controller unit connected to a pressure measurement unit for determining a pressure of the coupling liquid in the cavity and to detecting an increase of the pressure of the coupling liquid in the cavity, wherein the switching signal is generated if the detected pressure increase is above a predetermined pressure threshold value.

48. The method according to claim 46, further comprising the step of monitoring the pressure of the coupling liquid by means of a controller unit connected to a pressure measurement unit for determining a pressure of the coupling liquid in the cavity and to detecting an increase of the pressure of the coupling liquid in the cavity, and the switching signal is generated if the detected pressure increase is above a predetermined pressure threshold value and the measured pressure then drops below a second threshold value.

49. The method according to claim 46, further comprising the step of monitoring the pressure of the coupling liquid by means of a controller unit connected to a pressure measurement unit for determining a pressure of the coupling liquid in the cavity and to detecting a decrease of the pressure of the coupling liquid in the cavity, and a switching signal for switching the ultrasound treatment device from the second operating mode to the first operating mode is generated if the detected pressure decrease is below a pre-determined pressure threshold value.

50. The method according to claim 43, further comprising the step of switching to a third operating mode from the first or second operating mode, and in the third operating mode the pressure of the coupling liquid is maintained at a third pressure value higher than the second pressure value or the volume of the coupling liquid in the cavity is maintained to a third volume value.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0135] The invention will now be described in more detail by way of non-limiting, exemplary embodiments in connection with the drawings which show:

[0136] FIG. 1 schematically a device according to the present invention;

[0137] FIG. 2A an exemplary graph showing the coupling liquid pressure development;

[0138] FIG. 2B an exemplary graph showing the coupling liquid pressure development according to an alternative of the method of the present invention;

[0139] FIG. 3A a flow diagram of a method according to the present invention; and

[0140] FIG. 3B a flow diagram of another method according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0141] In FIG. 1 there is shown an embodiment of the device 1 according to the present invention. The device 1 comprises a probe head 2 with a concave HIFU transducer 3 and a B-mode imaging device 4. The HIFU waves emitted by the HIFU transducer 3 are focused, wherein the focus lies within the imaging plane of the imaging device 4.

[0142] The device 1 further comprises a flexible balloon 5 arranged at the distal side of the probe head 2 and defining a cavity 6, which is filled with a coupling liquid 7. The coupling liquid 7 is drawn from a reservoir 8, which is in fluid connections with the cavity 6 over lines 18 and 19. Coupling liquid is pumped into the cavity 6 by a pump 11 over the line 18 and exits the cavity via the line 19. A valve 12 for regulating the pressure inside the cavity 6 is arranged on the line 19. The pump 11 and the valve 12 therefore build a fluid control system 10 for controlling the pressure and/or the volume of the coupling liquid 7 in the cavity 6.

[0143] Inside the cavity, there is arranged a pressure sensor 9 for determining the coupling liquid pressure in the cavity 6. The HIFU transducer 2, the pressure sensor 9, the pump 11 and the valve 12 are connected to a controller unit 13 by a connection 20, which may be a wired connection such as a BUS or a wireless connection.

[0144] The controller unit 13 is adapted to control the operation of the device and is further connected to a force sensor 15 arranged on an operator's finger 21.

[0145] When the device 1 is operated, an object O is placed in contact with the balloon 5 and imaging of the object O is performed by means of the imaging device 4. A target T to be treated is located within the object O. An operator moves the probe head 2 and/or the object O such that the focus of the HIFU transducer 3 is located within the target T.

[0146] A possible curve of the pressure of the coupling liquid during operation is shown in FIG. 2A. The controller unit 13 keeps the pressure of the coupling liquid 7 in the cavity to a first pressure value P1. During this phase, which is also referred to as the first operating mode I (also shown schematically under the abscissa of the graph of FIG. 2), the probe head 2 is normally oriented such that the target T lies within the imaging plane of the imaging device 4.

[0147] In order to bring the target T in focus of the HIFU transducer 3, an operator starts compressing the object O, which is a soft tissue. Starting compression (schematically referred to in FIG. 2 as SC), however, leads to an undesired increase of the pressure of the coupling liquid 7.

[0148] If the pressure increase leads to a pressure value above a threshold value TS1, the controller unit 13 switches the operating mode from the first operating mode I to a second operating mode II. After switching to the second operating mode II, the controller unit 13 controls the valve 12 and the pump 11 in order to decrease the pressure to a second pressure value P2, which is higher than the first pressure value P1 kept constant during the first operating mode I.

[0149] The second pressure value P2 is then kept constant. Since the second pressure value P2 is higher than the first pressure value P1, the operator does not see the target slowly drift away from the focus as in devices known from the prior art operated with a constant pressure mode.

[0150] The emission of treatment HIFU waves is then triggered by the operator or automatically. After the emission of the HIFU waves, the operator stops compressing the object O (schematically referred to in FIG. 2 as RC).

[0151] The pressure drops below a threshold pressure value TS3, wherein as a response to the pressure drop under the threshold pressure value TS3, the controller unit 13 switches back to the first operating mode I, where pressure is adjusted to the first pressure value P1 and is then kept constant for the preparation of the object for the subsequent emission of HIFU waves.

[0152] An alternative of the method according to the present invention is shown in FIG. 2B, which is similar to the method shown in FIG. 2A with the difference that, when the pressure increase raises above the first threshold value TS1, the controller unit 13 does not switch directly in the second operating mode II. The pressure is controlled by the controller unit 13 and decreased. When the pressure drops below a second threshold value TS2, the controller unit 13 switches to the second operating mode II, and maintains the pressure constant to the second pressure value P2.

[0153] By switching to the second operating mode II just before the pressure has reached the second pressure value P2, the operator does not see the target slowly drift away from the focus as in devices known from the prior art operated with a constant pressure mode, because the slow adjustment phase is reduced or preferably avoided.

[0154] Data from the force sensor 15 may be used additionally or alternatively in order to increase the accuracy of the detection of the pressure changes. As an example, detection of strong compression by the force sensor 15 may be used to activate the fluid control system 10 for a fast reaction of the pressure adjustment.

[0155] An exemplary method according to the present invention is described hereinbelow with reference to the FIG. 3A:

[0156] The method is performed starting with a patient lying horizontally on a bed in a first step 100.

[0157] The device 1 is activated in the first operating mode I and positioned on the patient in a step 110, wherein imaging of the target T is performed by means of the imaging device 4.

[0158] The probe head 2 is then moved in a step 120 in order to roughly put the focus on the target T.

[0159] The device 1 is then switched to the second operating mode II, where the pressure P2 in the balloon is set to a value which induces a moderate compression on the tissue, which results in a partial collapse of the vein.

[0160] The probe head 2 is positioned at the centre of the vein segment to be treated in a step 130. Then, the device 1 is switched in the third operating mode III, causing the total collapse of the vein. The vein therefore becomes invisible.

[0161] The position of the focus in step 130 is adjusted based on the trial and error process described in the present invention, which implies switching between the second operating mode II and the operating mode III until the focus is at the desired position.

[0162] Then with the device in the third operating mode III, a pulse of treatment ultrasound waves is emitted in a step 140.

[0163] After the treatment ultrasound wave emission of step 140 an operator decides if the treatment is terminated or should be continued on the same target T or another target T in a step 150.

[0164] In the case the treatment is finished (YES) the method is terminated in a step 160. Otherwise (NO) the second operating mode II is activated and the pressure is decreased to the second pressure P2. The probe head 2 is then moved to the next target T according to the step 120. The method is then repeated until the desired tissue volume has been treated.

[0165] Another method according to the present invention is described herein below with reference to FIG. 3B:

[0166] The method is performed starting with a patient lying horizontally on a bed in a first step 100.

[0167] Then the patient it is placed in the Trendelenburg position to reduce the amount of blood within the vein in a step 110 and the device 1 is activated in the first operating mode I and manually positioned on the patient, wherein imaging of the target T is performed by means of the imaging device 4. The first pressure P1 in the balloon in step 110 is set to a low value which induces minimal (if any) compression on the tissue and enables easy manual handling of the head.

[0168] The probe head 2 is then moved robotically in a step 120 in order to roughly put the focus on the target T. The device 1 head is positioned at the centre of the vein segment to be treated.

[0169] The device 1 is then switched to the second operating mode II, where the pressure P2 in the balloon is set to a value which induces a moderate compression on the tissue, which results in a partial collapse of the vein.

[0170] The probe head 2 is positioned at the centre of the vein segment to be treated in a step 130. Then, the device 1 is switched in the third operating mode III. In this case the third pressure P3 does not cause the total collapse of the vein.

[0171] The vein is totally collapsed by manual pressure application by the operator in step 130.

[0172] The position of the focus is adjusted based on the trial and error process described in the present invention in step 130, which implies switching between the second operating mode II and the operating mode III until the focus is at the desired position.

[0173] Then, with the device in the third operating mode III and the operator manually compressing the tissue, a pulse of treatment ultrasound waves is emitted in a step 140.

[0174] After the treatment ultrasound wave emission, the second operating mode II is activated and the pressure is decreased to the second pressure P2 in a step 170.

[0175] A pulse of treatment ultrasound waves is emitted again in a step 140 with the vein partially collapsed, therefore inducing damages to the tissue by cavitation effects.

[0176] After the treatment ultrasound wave emission of step 140 an operator decides if the treatment of the target is terminated or should be continued on the same target T in a step 180.

[0177] In the case the treatment of the target T is not finished (NO), the method is performed again starting from step 120 on the same target, otherwise (YES) the operator has to decide in a step 150 if the entire treatment is terminated or not.

[0178] If the method has to be continued (NO in step 150) the method is performed again starting from step 110 by targeting a new target T. The method is then repeated until the desired tissue volume has been treated.

[0179] Otherwise, the method is terminated in a step 160.