DETERMINING A GUIDANCE SIGNAL AND A SYSTEM FOR PROVIDING A GUIDANCE FOR AN ULTRASONIC HANDHELD TRANSDUCER

Abstract

The present invention relates the device and the method for providing a guidance signal. The device preferably relates to a mobile device, such as a mobile tablet computer. The device comprises an input unit, a display and a processing unit. Via the input unit, a three-dimensional outline image of a surface of a human subject is provided, e.g. acquired by a camera. The device further comprises a memory. The memory stores a human reference model, which statistically represents a virtual human subject. In practice it is often the case that the surface outline represented by the human reference model would not instantly fit to the surface outline of the human subject. Therefore, the processing unit is configured to adapt the human reference model resulting in an adapted model, such that the surface outline represented by the adapted model fits to the surface outline of the (real) human subject. Furthermore, the image is acquired as a so-called track-image of an ultrasonic handheld transducer in front of the human subject. The processing unit is configured to recognize the ultrasonic handheld transducer in the track-image and to determine the transducer pose based thereon. In practice, the ultrasonic handheld transducer is to be arranged on the surface of the human subject at a target pose in order to scan a desired scan region of the human subject. The scan region may relate to an inner organ of the human subject. Based on the actual transducer pose and the desired target pose, the processing unit is configured to determine a guidance signal, which indicates how to move and/or rotate the ultrasonic handheld transducer to reach the desired target pose.

Claims

1. A device for determining a guidance signal, the device comprising: an input unit; and a processing unit; wherein the input unit is configured to receive an at least indirectly acquired outline image of a surface outline of a human subject; wherein the processing unit is configured to access a human reference model, which represents a surface outline of a virtual human subject, its internal morphology and a relation between its surface outline and its internal morphology; wherein the processing unit is configured to adapt the human reference model resulting in an adapted model, such that the surface outline represented by the adapted model fits to the surface outline of the human subject; wherein the processing unit is configured to access a transducer model, which represents a surface outline of an ultrasonic handheld transducer and a detection range of a probe of the ultrasonic handheld transducer, wherein the input unit is configured to receive the image acquired as a track-image of the ultrasonic handheld transducer and a surrounding region of the surface of the human subject surrounding the ultrasonic handheld transducer, when the ultrasonic handheld transducer is arranged on the surface of the human subject; wherein the processing unit is configured to recognize the ultrasonic handheld transducer in the track-imagc based on the transducer model deriving in a transducer pose of the ultrasonic handheld transducer with respect to the human subject; wherein the processing unit is configured to receive a target signal representing at least indirectly a scan region of the internal morphology of the adapted model; wherein the processing unit is configured to determine a target pose for the ultrasonic handheld transducer with respect to the human subject based on the target signal, the transducer model and the adapted model resulting in a virtual match of the detection range and the scan region; wherein the processing unit is configured to determine a guidance signal based on the transducer pose and the target pose, such that the guidance signal represents a guidance for moving and/or rotating the ultrasonic handheld transducer from the transducer pose to the target pose.

2. Device according to claim 1, wherein a camera unit is configured to at least indirectly acquire the outline image of the surface outline of the human subject; and wherein, preferably, the camera unit is configured to acquire the track-image of the ultrasonic handheld transducer and the surrounding region of the surface of the human subject surrounding the ultrasonic handheld transducer, when the ultrasonic handheld transducer is arranged on the surface of the human subject.

3. Device according to claim 1, wherein the human reference model comprises deformation data representing a relation between a deformation of the surface outline of the virtual human subject and a resulting deformation of the internal morphology of the virtual human subject; wherein the processing unit is configured to perform the adaptation of the human reference model based on the deformation data.

4. Device according to claim 1, wherein the device comprises; i) a display, and wherein the device is configured to illustrate at least one graphical clement via the display based on the guidance signal, such that the at least one graphical element indicates the guidance for moving and/or rotating the ultrasonic handheld transducer from the transducer pose to the target pose, and/or ii) an optical projector, in particular a laser beam projector, and wherein the device is configured to illustrate at least one graphical clement via the optical projector on the surface of the human subject based on the guidance signal, such that the at least one graphical element indicates the guidance for moving and/or rotating the ultrasonic handheld transducer from the transducer pose to the target pose.

5. Device according to claim 1, wherein the device is configured to perform at least one update; wherein for each update, the input unit is configured to receive an acquired further track-image of the ultrasonic handheld transducer and of a surrounding region of the surface of the human subject surrounding the ultrasonic handheld transducer as an updated track-image, when the ultrasonic handheld transducer is arranged on the surface of the human subject, and the processing unit is configured to recognize the ultrasonic handheld transducer in the updated track-image based on the transducer model deriving in the updated transducer pose of the ultrasonic handheld transducer with respect to the human subject; and wherein the processing unit is configured to update at least once the guidance signal based on the target pose and an previously updated transducer pose.

6. Device according to claim 1, 1. wherein the device is configured to access a transducer dataset comprising a plurality of different transducer basic-models, each representing a surface outline of an associated ultrasonic handheld transducer and a detection range of its probe; wherein the device is configured to receive a transducer selection signal, which indicates one of the plurality of the different transducer basic-models, and wherein the device is configured to select the transducer basic-model, which is indicated by the transducer selection signal, as the transducer model.

7. Device according to claim 1, wherein the device comprises an input panel, which may be formed by a or the display of the device; and wherein the input panel and the processing unit are configured to determine the transducer selection signal based on an external operation of the input panel.

8. Device according to claim 1, wherein the device comprises an input interface, which is configured to receive a transducer model signal, which represents the transducer model.

9. Device according to claim 1, wherein the device comprises an input interface, which is configured to receive the transducer selection signal.

10. Device according to claim 8, wherein the input interface is configured to establish a signal connection to the ultrasonic handheld transducer, such that the transducer model signal or the transducer selection signal is receivable from the ultrasonic handheld transducer.

11. Device according to claim 1, wherein the device comprises an input interface, which is configured to receive an ultrasonic signal from the ultrasonic handheld transducer; wherein the ultrasonic signal represents an ultrasonic image, being acquired by the ultrasonic handheld transducer and illustrating a morphology-segment of the human subject; wherein the processing unit is configured to update the adapted model, such that the internal morphology represented by the updated adapted model fits to the morphology-segment of the human subject; wherein the processing unit is configured to update the target pose for the ultrasonic handheld transducer with respect to the human subject based on the target signal, the transducer model and the updated adapted model resulting in a virtual match of the detection range and the scan region, and wherein the processing unit is configured to update the guidance signal based on the transducer pose and the updated target pose.

12. A system for providing a guidance for an ultrasonic handheld transducer, comprising: an ultrasonic handheld transducer; and a device according to any of the preceding claims, wherein the ultrasonic handheld transducer is configured to be arranged on the surface of a human subject; wherein the ultrasonic handheld transducer and the device are configured to transmit the guidance signal from the device to the ultrasonic handheld transducer, wherein the ultrasonic handheld transducer comprises an output unit, in particular with optical means and/or acoustical means, and wherein the ultrasonic handheld transducer is configured to indicate the guidance via the output unit based on the guidance signal.

13. A method for determining a guidance signal, comprising the following steps: a) providing an at least indirectly acquired outline image of a surface outline a human subject; b) accessing a human reference model, wherein the human reference model represents a surface outline of a virtual human subject, its internal morphology and a relation between its surface outline and its internal morphology; c) adapting the human reference model resulting in an adapted model, such that the surface outline represented by the adapted model fits to the surface outline of the human subject; d) accessing a transducer model, wherein the transducer model represents a surface outline of a ultrasonic handheld transducer and a detection range of a probe the ultrasonic handheld transducer; e) providing a track-image of the ultrasonic handheld transducer and a surrounding region of the surface of the human subject surrounding the ultrasonic handheld transducer, when the ultrasonic handheld transducer is arranged on the surface of the human subject; f) recognizing the ultrasonic handheld transducer in the track-image and based on the transducer model deriving in a transducer pose of the ultrasonic handheld transducer with respect to the human subject; g) receiving a target signal, wherein the target signal represents at least indirectly a scan region of the internal morphology of the adapted model; h) determining a target pose for the ultrasonic handheld transducer with respect to the human subject and based on the target signal, the transducer model and the adapted model resulting in a virtual match of the detection range and the scan region; and i) determining a guidance signal and based on the transducer pose and the target pose, such that the guidance signal represents a guidance for moving and/or rotating the ultrasonic handheld transducer from the transducer pose to the target pose.

14. (canceled)

15. A computer readable medium having stored the program element of claim 14.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0085] Exemplary embodiments of the invention will be described in the following with reference to the following drawings:

[0086] FIG. 1 schematically illustrates a first embodiment of the device as well as a first example of the ultrasonic handheld transducer in a first position.

[0087] FIG. 2 schematically illustrates the first embodiment of the device as well as the first example of the ultrasonic handheld transducer in a second position. FIG. 3 schematically illustrates a second embodiment of the device as well as the first example of the ultrasonic handheld transducer.

[0088] FIG. 4 schematically shows an exemplarily illustration of a screen of a display of the device.

[0089] FIG. 5 schematically illustrates an embodiment of the system according to the present invention.

[0090] FIG. 6 schematically illustrates an embodiment of the method according to the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0091] FIG. 1 schematically illustrates a device 2 for determining a guidance signal.

[0092] Furthermore, FIG. 1 schematically illustrates a human subject 10 and an ultrasonic handheld transducer 14. The ultrasonic handheld transducer 14 is arranged on a surface 22 of the human subject 10. The probe 18 of the ultrasonic handheld transducer 14 is directed towards the human subject 10. In order to arrange the ultrasonic handheld transducer 14 on the surface 22 of the human subject, the ultrasonic handheld transducer 14 may be arranged directly or indirectly on the surface 22 of the human subject 10, in particular with its probe 18. The probe 18 of the ultrasonic handheld transducer is associated with a detection range 16. The detection range 16 is preferably the range, where ultrasonic radiation is provided by the probe 18 of the ultrasonic handheld transducer 14 and preferably reflected from the human subject 10, such that the reflected radiation may be detected by the probe 18 of the ultrasonic handheld transducer 14. Thus, the detection range 16 may relate to the range associated with the probe 18 of the ultrasonic handheld transducer 14, where an ultrasonic detection can be carried out.

[0093] The ultrasonic handheld transducer 14 is preferably formed by a mobile ultrasonic handheld transducer 14. The ultrasonic handheld transducer may therefore be cordless. Thus, it may be positioned and/or oriented very flexible with respect to the surface 22 of the human subject 10. As a result thereof, often only expert medical staff may perform an ultrasonic examination via the ultrasonic handheld transducer 14 with reliable ultrasonic image results. In order to overcome this drawback, the device 2 is preferably configured to determine a guidance signal representing a guidance for moving and/or rotating the ultrasonic handheld transducer 14, such that a desired scan region 24 of the human subject 10 can scanned reliably via the ultrasonic handheld transducer 14, in particular handled by an unexperienced operator.

[0094] The device comprises an input unit and a processing unit 6. Preferably, the device 2 further comprises a display 26. The input unit of the device 2 is configured to at to receive an at least indirectly acquired outline (8) image of a surface outline of a human subject. For example, a camera unit 4 is provided to least indirectly acquire the outline image of the surface 8 of the human subject 10. In particular in the case, where the device 2 is formed by a mobile tablet computer the camera unit 4 may comprise a two-dimensional camera. Via the 2D camera a plurality of two-dimensional images may be acquired of the surface 8 of the human subject 10. Based on these two-dimensional images, the camera unit 4, and in particular in combination with the processing unit 6, may determine an outlined image (preferably as a three-dimensional image or a depth image) of the surface outline 8 of the human subject 10. Thus, the indirect acquiring of the outline image of the surface outline 8 of the human subject 10 may comprise the acquiring of a plurality of two-dimensional images and the determination of the outline image based on said plurality of two-dimensional images. The camera unit 4, however, may alternatively and/or additionally comprise a three-dimensional camera. This three-dimensional camera may be configured to directly acquire a three-dimensional outline image of the surface outline 8 of the human subject 10.

[0095] The processing unit 6 is configured to access a human reference model. This model may refer to a data model or a human reference data model. The device 2 may comprise a memory unit 28. The human reference model may be stored by the memory unit 28. Thus, the processing unit 6 may be configured to access the memory unit 28 in order to access the human reference model. Alternatively and/or additionally, the device 2 may comprise an interface 30. The interface 30 may also be referred to as an interface unit or a communication unit. The processing unit 6 may be configured to access the human reference model via the interface 30, in particular from a server or from the ultrasonic handheld device 14. For this purpose, a signal connection may be established between the interface 30 and the server or the ultrasonic handheld transducer 14, respectively. The signal connection may be a permanent signal connection or a temporarily established signal connection.

[0096] The human reference model represents a surface outline of a virtual human subject, its internal morphology and a relation between its surface outline and its internal morphology. Thus, the human reference model may serve as a reference model. It is desired to adapt the human reference model, such that the surface outline of the virtual human subject fits and/or matches to the previously acquired outline image of the surface outline 8 of the human subject 10. As a result of this fit and/or match procedure, the internal morphology represented by the human reference model would be adapted accordingly. In an example, the internal morphology represented by the human reference model represents at least one inner organ, at least a part of a skeleton and/or at least a part of a vascular system of the virtual human subject. Thus, the internal morphology represented by the human reference model may represent anatomical structures of the virtual human subject. Adapting the human reference model, such that surface outline of the adapted model fits to the surface outline of the human subject 10, would also result in an accordingly adapted internal morphology of the adapted model, such that the internal morphology of the adapted model would represent an estimation of the internal morphology of the human subject 10. In other words, the processing unit 6 is configured to adapt the human reference model resulting in the adapted model, such that the surface outline represented by the adapted model fits to the surface outline of the human subject 10. As discussed before, the adaptation of the human reference model resulting in the adapted model should be carried out to the whole human reference model. As a result, an analogous adaptation will be subject to the internal morphology. The adapted model may represent a surface outline (which fits to the surface outline of the human subject), an adapted internal morphology and a relation between the adapted surface outline and its adapted internal morphology. As an effect, the adapted model may provide a good estimation of a position and/or orientation of internal anatomical structures of the human subject 10, which are not visible from the outside or from the outline image of the surface outline 8 of the human subject 10. For example, the adapted model may encode a typical statistical relation between the surface outline 8 of the human subject 10 and the location and/or shape of internal organs. Therefore, the adapted model may provide the basis to provide a possible prediction of a shape and/or location of an internal organ.

[0097] The camera unit 4 is further configured to acquire a track-image of the ultrasonic handheld transducer 14 and a surrounding region 20 of the surface 22 of the human subject 10 surrounding the ultrasonic handheld transducer 14, when the ultrasonic handheld transducer 14 is arranged on the surface 22 of the human subject 10. In this context, it may be noted that the outline image of the surface outline 8 of the human subject 10 (previously acquired) preferably represents the surface outline 8 of the human subject 10 without the ultrasonic handheld transducer 14 being arranged on the surface 22 of the human subject 10.

[0098] Further, the processing unit 6 is configured to access a transducer model. The transducer model may be a data model. The transducer model may be stored on the memory unit 28 of the device 2. Alternatively or additionally, the transducer model may be accessed via the interface 30. Thus, the transducer model may be accessed via the interface 30 from a server or from the ultrasonic handheld transducer 14. With respect to the signal connection, all the respective explanations, examples and/or effects may also to be intended as being provided in an analogous manner for this signal connection.

[0099] The transducer model represents a surface outline 12 of the ultrasonic handheld transducer 14 and the detection range 16 of the probe 18 of the ultrasonic handheld transducer 14. Thus, the transducer model may provide the information to the processing unit 6 with respect to the surface outline 12 of the ultrasonic handheld transducer 14, which is illustrated in the track-image.

[0100] The processing unit 6 is therefore further configured to recognize the ultrasonic handheld transducer 14 in the track-image based on the transducer model deriving in a transducer pose of the ultrasonic handheld transducer 14 with respect to the human subject 10. The track-image illustrates the surrounding region 20 of the surface 22 of the human subject 10 surrounding the ultrasonic handheld transducer 14. Thus, a registration of said surrounding region 20 may be performed with respect to the outline image. Furthermore, the ultrasonic handheld transducer 14 may be recognized in the track-image. Thus, the processing unit 6 may be configured based on these information to determine the transducer pose of the ultrasonic handheld transducer 14 with respect to the human subject 10. The transducer pose may relate to the position and/or orientation of the ultrasonic handheld transducer 14 with respect to the human subject 10.

[0101] Furthermore, the transducer model represents the detection range 16 of the probe 18 of the ultrasonic handheld transducer 14. With respect to FIG. 1, the processing unit 6 may be configured to determine which part of the human subject 10 is scanned via the ultrasonic handheld transducer 14 based on the transducer pose of the ultrasonic handheld transducer 14 and the detection range 16. As can be taken from picture 1, the detection range 16 may be arranged below a desired scan region 24, where the human subject 10 should be scanned at. In order to determine, whether the detection range 16 matches with the desired scan region 24, the processing unit 6 may need information about the scan region 24.

[0102] The processing unit 6 is therefore configured to receive a target signal representing at least indirectly a scan region 24 of the internal morphology of the adapted model. Since the adapted model was previously determined in order to match with the human subject 10, the scan region 24 will very likely also represent the scan region of the internal morphology of the human subject 10. For simplicity reason, a match is assumed. Thus, the scan region 24 may refer to the human subject as well as to the adapted model. The target signal may be provided to the processing unit 6 via the interface 30. Alternatively or additionally, the display 26 may be a touch screen. An operator may be able to provide an input signal via touching the touch screen to the processing unit 6, wherein the input signal represents the target signal or may provide the based to determine the target signal. For instance, the internal morphology of the adapted model may be at least partly displayed on the touch screen (display 26), such that an operator can select a particular inner organ. Based on this selection, the target signal may be determined via the processing unit 6.

[0103] The processing unit 6 is configured to determine a target pose for the ultrasonic handheld transducer 14 with respect to the human subject based on the target signal, the transducer model and the adapted model, such that a virtual match of the detection range 16 and the scan region 24 is achieved. Thus, if an operator would arrange the ultrasonic handheld transducer 14 in the target pose, the detection range 16 of the ultrasonic handheld transducer 14 would match or capture the scan region 24 of the human subject. This is exemplarily illustrated in FIG. 2. However, the handheld transducer 14 is preferably held in the operator's hand. Thus, it is desired to provide an information to the operator how to change the position and/or orientation of the ultrasonic handheld transducer 14, such that the ultrasonic handheld transducer 14 would scan the desired scan region 24 of the human subject 10. For this purpose, the processing unit 6 is configured to determine a guidance signal based on the transducer pose and the target pose, such that the guidance signal represents a guidance for moving and/or rotating the ultrasonic handheld transducer 14 from the transducer pose to the target pose. In an example, the guidance signal may represent the guidance for moving the ultrasonic handheld transducer 14 in an arbitrary direction and/or for rotating the ultrasonic handheld transducer 14 about an arbitrary axis, in particular about one axis associated with the ultrasonic handheld transducer 14.

[0104] FIG. 4 exemplarily illustrates a screenshot of the display 26. The device 2 may be configured to illustrate at least one graphical element 32 via the display 26 based on the guidance signal, such that the at least one graphical element 32 indicates the guidance for moving and/or rotating the ultrasonic handheld transducer 14 from the transducer pose to the target pose.

[0105] From the synopsis of FIG. 1 and FIG. 2, it may be taken that the guidance signal should represent an upward movement of the ultrasonic handheld transducer 14. As a result, the device 2 may illustrate an arrow directed upwards via the display 26, as it is exemplarily shown in FIG. 4. Thus, an operator may receive the guidance to move the ultrasonic handheld transducer 14 upwards, in order to move it from the transducer pose shown in FIG. 1 towards the target pose for the ultrasonic handheld transducer 14, as it is exemplarily illustrated in FIG. 2. If the ultrasonic handheld transducer 14 reaches the target pose, a scan of the scan region 24 may be performed via the ultrasonic handheld transducer 14.

[0106] As can be exemplarily taken from FIG. 3, the device 2 may comprise a projector 34, in particular a laser beam projector. The device 2 may be configured to optically illustrate at least one graphical element 32 via the projector 34 on the surface 22 of the human subject based on the guidance signal, such that the at least one graphical element 34 indicates the guidance for moving and/or rotating the ultrasonic handheld transducer 14 from the transducer pose to the target pose. The graphical element may be formed in an analogous manner to the graphical element 32 shown in FIG. 4. Thus, an arrow may be projected on the surface 22 via the projector 34. As an effect, an operator of the ultrasonic handheld transducer 14 may receive the information to move the ultrasonic handheld transducer 14 upwards in order to achieve a match of the actual transducer pose and the target pose.

[0107] Furthermore, the device 2 may comprise an acoustical output means, for instance a loudspeaker. The device 2 may be configured to output an acoustical signal, for instance a synthesized, predetermined speech, via the loudspeaker based on the guidance signal, such that the acoustical signal indicates the guidance for moving and/or rotating the ultrasonic handheld transducer from the transducer pose to the target pose.

[0108] With respect to the graphical element illustrated in FIG. 4, this graphical element 32 may give an operator of the ultrasonic handheld transducer 14 a rather qualitative information than a quantitative information. Thus, the operator may move the ultrasonic handheld transducer 14 upwards for a small distance. This distance may not be sufficient in order to achieve a match of the actual transducer pose and the target pose. Thus, it would be desired to provide the operator with a number of subsequent graphical elements 32 illustrated on the display 26 and/or via the projector 34, such that the operator can move and/or rotate the ultrasonic handheld transducer 14, until the desired match of the actual transducer pose and the target pose is achieved. Thus, the device 2 may be configured to update the guidance signal and/or the illustration of the graphical element 32.

[0109] In an example, the device 2 is configured to perform at least one update, wherein for each update, the camera unit 4 is configured to acquire a further track-image of the ultrasonic handheld transducer 14 and of a surrounding region 20 of the surface 22 of the human subject 10 surrounding the ultrasonic handheld transducer 14 as updated track-image, when the ultrasonic handheld transducer 14 is arranged on the surface 22 of the human subject, and wherein the processing unit 6 is configured to recognize the ultrasonic handheld transducer 14 in the updated track-image based on the transducer model deriving in the updated transducer pose of the ultrasonic handheld transducer 14 with respect to the human subject 10. The processing unit 6 may be further configured to update at least once the guidance signal based on the target pose and the previously updated transducer pose. After each update of the guidance signal, the device 2 may be configured to update the illustration of the at least one graphical element 32 based on the last updated guidance signal, such that the at least one graphical element 32 indicates the updated guidance for moving and/or rotating the ultrasonic handheld transducer from the updated transducer pose to the target pose.

[0110] In an example, the device 2 is configured to access a transducer dataset. The transducer dataset may also be referred to a dataset as such. The transducer dataset may be stored on the memory unit 28 of the device 2. Alternatively or additionally, the transducer dataset may be accessed via the interface 30, in particular from a server. For this purpose, a permanent or temporary signal connection may be established via the interface 30 to the server. The transducer dataset comprises a plurality of different transducer basic-models. Each of the transducer basic-models may be formed in an analogous manner to the transducer model. However, the basic-models are different among each other. Thus, each of the transducer basic-models represents a surface outline of an associated ultrasonic handheld transducer 14 and a detection range 16 of its probe 18. Each of the transducer basic-models may therefore refer to another actual ultrasonic handheld transducer 14, in particular each of a different type.

[0111] The device 2 is further configured to receive a transducer selection signal. The transducer selection signal may be a signal as such. The interface 30 of the device 2 may be configured to receive said transducer selection signal. Alternatively and/or additionally, the device 2 may comprise an input panel, which may be formed by the display 26 as a touch screen. Thus, the input panel and the processing unit 6 may be configured to determine the transducer selection signal based on an external operation of the input panel, for instance a touch at the touch screen. For example, the device 2 may be configured to control the display 26, such that at least a subset of the transducer basic-models is indicated on the display 26. An operator may select via a touch on the display 26 one of the items in the list and thus may select one of the transducers represented by the respective transducer basic-model indicated at list's item on the display 26. Based thereon, the processing unit 6 may be configured to determine the respective transducer selection signal. The processing unit 6 may be further configured to select the transducer basic-model, which is indicated by the transducer selection signal, as the transducer as such. As an effect, the device 2 may be configured to cooperate with each of a plurality of different kinds and/or types of ultrasonic handheld transducers 14. Further, the processing unit 6 may therefore be able to recognize an arbitrary ultrasonic handheld transducer 14 in the track-image, if the respective transducer model has been previously selected from the plurality of different transducer basic-models.

[0112] In particular in the case, where the transducer dataset comprising the plurality of different transducer basic-models is not stored on the memory unit 28, the device 2 may be configured to receive the transducer model differently. For example, the device 2 may be configured to receive a transducer model signal via the interface 30, wherein the transducer model signal represents the transducer model. Thus, the transducer model signal may be transmitted to the device 2 beforehand in order to store the transducer model in the memory unit 28. Thereafter, the processing unit 6 may access the respective transducer model from the memory unit 28 in order to use the transducer model for instance for the recognition of the ultrasonic handheld transducer 14 in the track-image.

[0113] In an example, the input interface 30 of the device 2 is configured to establish a signal connection to the ultrasonic handheld transducer 14, such that the transducer model signal and/or the transducer selection signal is receivable from the ultrasonic handheld transducer 14. In an example, the ultrasonic handheld transducer 14 may comprise a (further) memory unit, which stores the transducer model corresponding to the respective ultrasonic handheld transducer 14. Thus, if the device 2 is to be used to cooperate with the respective ultrasonic handheld transducer 14, the signal connection may be at least temporarily established in order to transmit the transducer model signal to the device 2 via the interface 30, such that the transducer model can be stored in the memory unit 28 of the device 2. Similarly, the signal connection may be established in order to transmit the transducer selection signal to the device 2, wherein the transducer selection signal may represent information about the respective ultrasonic handheld transducer 14, for instance its model number and/or any other identification number. Thus, the device 2 may select the respective transducer basic-model based on the transmitted transducer selection signal, for instance indicating the model number of the respective ultrasonic handheld transducer 14, from the plurality of different transducer basic-models, such that the selected transducer basic-model will form the transducer model for the further purpose. Since the ultrasonic handheld transducer 14 may be generally configured to scan at least a part of the internal morphology of the human subject 10, the respective information may be used to improve the adapted model, in particular the internal morphology represented by the adapted model. Thus, an ultrasonic image acquired via the ultrasonic handheld transducer 14 may be transmitted to the device 2 in order to subsequently improve the adapted model, such that the adapted model would subsequently estimate the actual internal morphology of the human subject 10 more precisely.

[0114] In an example, the device 2 comprises the input interface 30, which is configured to receive an ultrasonic signal from the ultrasonic handheld transducer 14. The ultrasonic signal may be a signal as such. The ultrasonic signal may represent an ultrasonic image being acquired by the ultrasonic handheld transducer 14 and illustrating at least a morphology-segment of the human subject 10. The processing unit 6 of the device 2 may be configured to update the adapted model, such that internal morphology represented by the updated adapted model fits to the morphology-segment of the human subject 10. The processing unit 6 may further be configured to update the target pose for the ultrasonic handheld transducer 14 with respect to the human subject 10 based on the target signal, the transducer model and the updated adapted model resulting in a virtual match of the detection range and the scan region. The processing unit may further be configured to update the guidance signal based on the transducer pose and the updated target pose. Furthermore, the device 2 may be configured to update the illustration of the at least one graphical element.

[0115] As an effect, the at least one ultrasonic image acquired by the ultrasonic handheld transducer 14 may serve as a basis to perform an update of the target pose resulting in a subsequent update of the guidance signal. Further, the illustration of the at least one graphical element 32 may be updated to provide the operator of the ultrasonic handheld transducer 14 with the latest information how to move and/or rotate the ultrasonic handheld transducer 14 in order to achieve a match between the actual transducer pose and the updated target pose.

[0116] FIG. 5 schematically illustrates an example of the system 36 for providing a guidance for an ultrasonic handheld transducer 14. The system 36 comprises an ultrasonic handheld transducer 14 and a device 2. It is to be understood that, without repeating here all the examples, effects and/or explanations provided with reference to the device 2 as such and/or the ultrasonic handheld transducer 14 as such, the system 36 may be intended as comprising the device 2 and/or the ultrasonic handheld transducer 14 as described above. Thus, all the above provided examples, explanations, effects and/or advantages, provided with reference to the device 2 and/or the ultrasonic handheld transducer 14, may also be intended as being implemented by the system 36. Thus, the ultrasonic handheld transducer 14 is configured to be arranged on the surface 22 of the human subject 10. The ultrasonic handheld transducer 14 and the device 2 are configured to transmit a guidance signal from the device 2 to the ultrasonic handheld transducer 14. For this purpose, a signal connection 38 may be established between the device 2 and the ultrasonic handheld transducer 14. In an example, the signal connection 38 may be provided via a cable connection between the device 2 and the ultrasonic handheld transducer 14. The cable connection may be established between the interface 30 of the device 2 and a further interface 40 of the ultrasonic handheld transducer 14. Instead of a cable connection, a radio signal connection may be established between the interface 30 of the device 2 and the interface 40 of the ultrasonic handheld transducer 14. The ultrasonic handheld transducer comprises an output unit 42 in particular with optical means and/or acoustical means. The ultrasonic handheld transducer 14 is configured to indicate the guidance via the output unit 42 based on the guidance signal. Thus, the ultrasonic handheld transducer 14 may indicate via the output unit 42, in particular via the optical means, how to move and/or rotate the ultrasonic handheld transducer 14, such that an operator can achieve a match between the actual transducer pose and the target pose. FIG. 6 schematically illustrates an example of the method 44 for determining a guidance signal. The method 44 comprises the following:

[0117] In a first step a), an outline image of a surface outline of a human subject 10 is acquired at least indirectly via a camera unit 4 of a device 2.

[0118] In a second step b), a human reference model is accessed via a processing unit 6 of the device 2, wherein the human reference model represents a surface outline of a virtual human subject, its internal morphology and a relation between its surface outline and its internal morphology.

[0119] In a third step c), the human reference model is adapted via the processing unit 6 resulting in an adapted model, such that the surface outline represented by the adapted model fits to the surface outline of the human subject 10.

[0120] In a fourth step d), a transducer model is accessed via the processing unit 6, wherein the transducer model represents a surface outline of the ultrasonic handheld transducer 14 and a detection range of a probe 18 of the ultrasonic handheld transducer 14.

[0121] In a fifth step e), a track-image of the ultrasonic handheld transducer 14 and a surrounding region 20 of the surface 22 of the human subject 10 surrounding the ultrasonic handheld transducer 14 is acquired via the camera unit 4, when the ultrasonic handheld transducer 14 is arranged on the surface 22 of the human subject 10.

[0122] In a sixth step f), the ultrasonic handheld transducer 14 is recognized in the track-image via the processing unit 6 and based on the transducer model deriving in a transducer pose of the ultrasonic handheld transducer 14 with respect to the human subject.

[0123] In a seventh step g), a target signal is received via the processing unit 6, wherein the target signal represents at least indirectly a scan region 24 of the internal morphology of the adapted model.

[0124] In an eighth step h), a target pose of the ultrasonic handheld transducer 14 with respect to the human subject 10 is determined via the processing unit 6 and based on the target signal, the transducer model and the adapted model resulting in a virtual match of the detection range 16 and the scan region 24.

[0125] In a ninth step i), a guidance signal is determined via the processing unit 6 and based on the transducer pose and the target pose, such that the guidance signal represents a guidance for moving and/or rotating the ultrasonic handheld transducer 14 from the transducer pose to the target pose.

[0126] According to a further example of the present invention, a computer program element is provided, which, when being executed by a processing unit is adapted to carry out the method described above.

[0127] According to further example of the present invention, a computer readable medium having stored thereon a program element is provided, which, when being executed by a processing unit is adapted to carry out the method described above. In another exemplary embodiment of the present invention, a computer program or a computer program element is provided that is characterized by being adapted to execute the method steps of the method according to one of the preceding embodiments, on an appropriate system.

[0128] The computer program element might therefore be stored on a computer unit, which might also be part of an embodiment of the present invention. This computing unit may be adapted to perform or induce a performing of the steps of the method described above. Moreover, it may be adapted to operate the components of the above described apparatus. The computing unit can be adapted to operate automatically and/or to execute the orders of a user. A computer program may be loaded into a working memory of a data processor. The data processor may thus be equipped to carry out the method of the invention. This exemplary embodiment of the invention covers both, a computer program that right from the beginning uses the invention and a computer program that by means of an up-date turns an existing program into a program that uses the invention.

[0129] Further on, the computer program element might be able to provide all necessary steps to fulfil the procedure of an exemplary embodiment of the method as described above.

[0130] According to a further exemplary embodiment of the present invention, a computer readable medium, such as a CD-ROM, is presented wherein the computer readable medium has a computer program element stored on it which computer program element is described by the preceding section. 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.

[0131] However, the computer program may also be presented over a network like the World Wide Web and can be downloaded into the working memory of a data processor from such a network. According to a further exemplary embodiment of the present invention, a medium for making a computer program element available for downloading is provided, which computer program element is arranged to perform a method according to one of the previously described embodiments of the invention.

[0132] It has to be noted that embodiments of the invention are described with reference to different subject matters. In particular, some embodiments are described with reference to a device whereas other embodiments are described with reference to the method. However, a person skilled in the art will gather from the above that, unless otherwise notified, in addition to any combination of features belonging to one subject matter also any combination between features relating to different subject matters is considered to be disclosed with this application. However, all features can be combined providing synergetic effects that are more than the simple summation of the features.

[0133] 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. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing a claimed invention, from a study of the drawings, the disclosure, and the dependent claims.

[0134] 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. A single processing unit or other unit may fulfil the functions of several items re-cited in the claims. The mere fact that certain measures are re-cited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.