Ultrasound method and device for characterising a medium of interest

Abstract

The present disclosure relates to an ultrasound method and corresponding device (10) using an ultrasound probe (20). The method comprises: obtaining first ultrasound data (DT1) from a region of interest (M) during a first ultrasound scan (SC1); detecting, from the first ultrasound data (DT1), mechanical activity (30) occurring at a time tx in the region of interest; determining a scan period on the basis of the time tx; and determining second ultrasound data (DT2) acquired from the region of interest (M) during a second ultrasound scan (S2) during the scan period.

Description

DESCRIPTION Title: Ultrasonic method and device for characterizing a medium of interest Prior art

[0001] The present disclosure relates to scans, or observations using ultrasound-type waves and relates more particularly to an ultrasound device and a corresponding method aimed at characterizing a region of interest using an ultrasound probe.

[0002] Ultrasonic devices now have many applications, particularly in the fields of acoustics, materials science, medical and veterinary imaging, as well as in the field of biomedicine.

[0003] For this purpose, an ultrasound device generally comprises an ultrasound probe controlled by means of electrical signals, these signals being for example transmitted between the probe and a control unit. The ultrasound probe comprises ultrasound transducer elements intended to emit and / or receive ultrasound waves to and / or from a region of interest. Electrical signals representing ultrasound waves can be transmitted to and / or received from these transducer elements, respectively causing the emission and / or reception of ultrasound waves in and / or from the medium in question.

[0004] Thus, from a series of insonifications of the medium using transducer elements, it is possible to receive and analyze the echoes backscattered by this same medium. In ultrasound imaging for example, also called echography, the processing of these ultrasonic echoes makes it possible to generate various information relating to the medium studied, such as an image according to an appropriate mode, such as a B mode (i.e. a two-dimensional mode of intensity of the received signal), a Doppler mode or a shear wave elastography mode also called SWE for "ShearWave® Elastography".

[0005] However, ultrasound data acquired during an ultrasound scan are not always satisfactory in terms of accuracy and reliability. The quality of ultrasound data can be limited by various factors. In particular, it has been observed that certain mechanical pressures applied on or in the region of interest during an ultrasound scan can lead to unwanted artifacts or measurement defects and significantly degrade the quality of the ultrasound data. These problems can significantly limit the performance of an ultrasound device in various application areas.

[0006] In particular, it has been observed that when a medium of interest undergoes deformation induced by mechanical pressure (or mechanical activity), this can disturb the ultrasound waves (e.g., but not exclusively, shear waves as used in the ShearWave® mode) acquired during an ultrasound scan and lead to artifacts, particularly in ultrasound imaging applications, which can mask or distort certain relevant information and make it more difficult to analyze the ultrasound data and / or images constructed thereon.

[0007] Such mechanical pressure may arise from various sources depending on the specific case and is not always detectable or controllable. This is particularly the case for certain mechanical pressures that may occur involuntarily or uncontrollably in, or near, the region of interest, for example in a living human body.

[0008] For example, it has been observed that a subject's cardiac or arterial activity can significantly disrupt an ultrasound observation due to internal deformations caused in or near the region of interest. Mechanical pressure due, for example, to heartbeats or abdominal aortic activity can thus significantly impact the quality of ultrasound data obtained during an ultrasound scan. These pulsations create movements and pressure variations that can cause artifacts or measurement defects, particularly in regions close to the heart or in highly vascularized regions.

[0009] This is why, historically, ultrasound scans intended to study the liver, particularly to measure its hardness, are limited to the right lobe, in accordance with the recommendations issued by the scientific world. It is commonly accepted that the results obtained on the left lobe of the liver, particularly in elastometry mode, are less or even unreliable, mainly due to artifacts induced by the mechanical pressure exerted by the heart (located above the diaphragm) and by the abdominal aorta (located behind the left lobe). This limitation can be problematic in the context of diffuse liver diseases such as fibrosis, steatosis and inflammation, which do not manifest homogeneously throughout the liver. In addition, elastometry acquisitions of the right lobe can also be disturbed by cardiac pulsations or the pulsatility of the large vessels contained in all segments of the liver.

[0010] The above-mentioned problems are not exclusive to ultrasound scanning of the liver. Other anatomical parts are also affected, for example the breast, especially the left breast in women due in particular to the mechanical pressure exerted by its vascular network and its proximity to the heart. Similar difficulties negatively impact the ultrasound observation of certain soft tissues, which are particularly exposed to deformation.

[0011] The problems described above disrupt or even hinder ultrasound scans in various fields, including but not limited to ultrasound imaging. These phenomena are particularly problematic for certain ultrasound imaging modes, such as shear wave elastography. In this mode, which aims to assess the stiffness of scanned tissues, the application of unwanted mechanical pressure can distort stiffness measurements, leading to erroneous results or inaccurate assessments.

[0012] However, other ultrasound imaging modes are also affected. In the case of Doppler mode, for example, so-called wall artifacts also disrupt the analysis of vascularization because they overlap with Doppler signals coming from flow analysis and not from tissues. Disclosure Statement

[0013] One of the purposes of this disclosure is to address at least one of the problems or deficiencies described above.

[0014] In particular, an object of the present disclosure is to perform a high-performance ultrasound scan despite movements of (or in) the region of interest.

[0015] In particular, an object of the present disclosure is to obtain accurate and reliable ultrasound data by an ultrasound scan of a region of interest, despite deformations or movements caused by mechanical activity exerted on and / or in the region of interest.

[0016] To this end, according to a first aspect, the present disclosure relates to an ultrasonic method using an ultrasonic probe, the method comprising: - obtaining initial ultrasound data from a region of interest during a first ultrasound scan; - detection, from the first ultrasound data, of a mechanical activity occurring at an instant tx in the region of interest; - determination of a scan period as a function of the instant tx; and - determination of second ultrasound data acquired from the region of interest during a second ultrasound scan during the scanning period.

[0017] The method according to the disclosure may include other features which may be taken separately or in combination, in particular among the following embodiments which are presented for illustrative purposes only and may be combined or associated unless otherwise stipulated.

[0018] In one example, the region of interest is all or part of a subject, the mechanical activity being representative of a biological activity of the subject.

[0019] In one example, the biological activity of the subject comprises at least one of cardiac activity or arterial activity of the subject.

[0020] In one example, the mechanical activity corresponds to all or part of a diastolic or systolic phase of the subject's cardiac activity.

[0021] According to one example, the detection of mechanical activity includes: - determination of a wave parameter from the first ultrasonic data; - comparison of said wave parameter with a threshold value; and - detection of mechanical activity from a result of said comparison.

[0022] According to an example, determining a scan period includes: - selection, as a scan period, of a period respecting a selection criterion in relation to the instant tx.

[0023] In one example, determining the scan period includes any one of: - selection, as scan period, of a period comprising the instant tx or an instant ty depending on tx; and - selection, as scan period, of a period distinct from the instant tx or an instant ty depending on tx.

[0024] In one example, the second ultrasound data coincides with the scan period.

[0025] In one example, determining the second ultrasound data is performed by triggering the second ultrasound scan during the scan period, after the first ultrasound scan, the second ultrasound data being distinct from the first ultrasound data.

[0026] For example, performing the second ultrasound scan includes: - sending signals to the ultrasound probe to cause the emission of ultrasonic or shear waves only during the scanning period.

[0027] In one example, the first ultrasound scan is stopped before, or at the same time as, the triggering of the second ultrasound scan.

[0028] According to one example, the method comprises: - detecting, from the first ultrasonic data, a plurality of mechanical activities occurring at respective times tx in the region of interest; - prediction, from the respective instants ty, of at least one future theoretical instant tx during which a said mechanical activity must occur; and - determination, from said at least one future theoretical instant ty, of the scan period.

[0029] According to one example, a plurality of future theoretical times ty are predicted from the respective times tx, wherein the scan period determined from the plurality of future theoretical times ty comprises a sequence of a plurality of successive and time-spaced scan periods.

[0030] According to one example, the first ultrasound scan is stopped before, or at the same time as, the start of the sequence of said plurality of successive and time-spaced scan periods.

[0031] According to one example, the determination of the second ultrasonic data is performed retrospectively by selecting, as the second ultrasonic data, a portion of the first ultrasonic data.

[0032] In one example, the region of interest includes one of: - all or part of the right or left lobe of a liver; - all or part of a breast; and - muscle fibers.

[0033] According to one example, said method is applied to ultrasound medical imaging.

[0034] According to a second aspect, the present disclosure may involve a computer program comprising instructions which, when the program is executed by a computer, cause the implementation of the method according to the first aspect. In particular, the different steps of the method according to the first aspect may be defined by computer program instructions.

[0035] Such a computer program may use any programming language or equivalent, and may be in the form of source code, object code, or code intermediate between source code and object code, such as in a partially compiled form, or in any other desirable form.

[0036] According to a third aspect, the present disclosure relates to a recording medium (or information medium), readable by a computer (or a processor), on which a computer program is recorded according to this same aspect of the present disclosure.

[0037] On the one hand, the recording medium may be any entity or device capable of storing the program, such as at least one volatile and / or non-volatile memory. For example, the medium may comprise a storage means, such as a rewritable non-volatile memory, a ROM memory, a CD-ROM or a ROM memory of the microelectronic circuit type, or even a magnetic recording means or a hard disk. This memory may for example comprise a graphics card (or video card) memory, this type of memory being in particular capable of processing image data (or video data).

[0038] Furthermore, this recording medium may also be a transmissible medium such as an electrical or optical signal, such a signal being able to be conveyed via an electrical or optical cable, by conventional or hertzian radio or by self-directed laser beam or by other means. The computer program according to the present disclosure may in particular be downloaded using a wired or non-wired network, of local or non-local type (Bluetooth® for example, Wi-Fi, Ethernet, Internet, 4G, 5G or others).

[0039] Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to perform or to be used in performing the method in question.

[0040] According to a fourth aspect, the present disclosure relates to a device for controlling an ultrasound scan capable of cooperating with an ultrasound probe, this device being configured to implement the method of the first aspect of the present disclosure.

[0041] In one example, the processing device includes a memory associated with a processor, the memory including a computer program according to the present disclosure.

[0042] According to one example, the present disclosure relates to a control device capable of cooperating with an ultrasonic probe, said device comprising: - an obtaining module configured to obtain first ultrasound data acquired by the ultrasound probe from a region of interest during a first ultrasound scan; - a detection module configured to detect, from the first ultrasound data, a mechanical activity occurring at a time tx in the region of interest; - a first determination module configured to determine a scan period as a function of the instant tx; and - a second determination module configured to determine second ultrasound data acquired from the region of interest during a second ultrasound scan during the scan period.

[0043] By implementing the present disclosure, it advantageously becomes possible to perform a high-performance ultrasound scan despite movements of (or in) the region of interest. In particular, it is advantageously possible to obtain accurate and reliable ultrasound data by an ultrasound scan of a region of interest, despite deformations caused by mechanical activity, or mechanical pressure, exerted on and / or in the region of interest.

[0044] Thanks to the disclosure, it is for example advantageously possible to carry out a good quality ultrasound observation of the right and / or left lobe of the liver of a subject, while minimizing or avoiding the appearance of artifacts or measurement defects due to heartbeats and / or the pulsatility of the arteries.

[0045] Thanks to the disclosure, it is for example advantageously possible to carry out a good quality ultrasound observation of a subject's breast, in particular the left breast, despite its proximity to the heart and its particularly dense vascular network, while minimizing or avoiding the appearance of artifacts or measurement defects due to heartbeats as previously described.

[0046] Thanks to the disclosure, it is for example advantageously possible to carry out good quality ultrasound observation of soft tissues, such as adipose tissues, or even muscle fibers, while minimizing or avoiding the appearance of artifacts or measurement defects due to heartbeats.

[0047] The characteristics and advantages of the disclosure will appear more precisely on reading the description which follows, given solely as a non-limiting example, and made with reference to the appended figures. In particular, the examples illustrated in the figures can be combined with each other, except in the case of obvious inconsistency. Brief description of the figures

[0048] Other characteristics and advantages of the present disclosure will emerge from the description of the non-limiting exemplary embodiments of the present disclosure set out below, with reference to the appended figures 1 to 9, in which:

[0049] [Fig. 1] schematically represents the acquisition of an ultrasound image according to an example of the prior art;

[0050] [Fig. 2] schematically represents an ultrasonic system, comprising a control device and an ultrasonic probe, according to exemplary embodiments of the present disclosure;

[0051] [Fig. 3] schematically represents the ultrasound system of Fig. 2, according to exemplary embodiments of the present disclosure;

[0052] [Fig. 4] schematically represents the control device of Figure 2, according to exemplary embodiments of the present disclosure;

[0053] [Fig. 5] schematically represents in the form of a diagram the steps of an ultrasonic method implemented by a control device, according to exemplary embodiments of the present disclosure;

[0054] [Fig. 6] schematically represents the implementation of the ultrasonic method of FIG. 5, according to a first exemplary embodiment of the present disclosure;

[0055] [Fig. 7] schematically represents the implementation of the ultrasonic method of Figure 5, according to a second exemplary embodiment of the present disclosure;

[0056] [Fig. 8] schematically represents the implementation of the ultrasonic method of Figure 5, according to an exemplary embodiment of the present disclosure; and

[0057] [Fig. 9] schematically represents the implementation of the ultrasonic method of Figure 5, according to an exemplary embodiment of the present disclosure. Description of the embodiments

[0058] The present disclosure relates to ultrasonic methods and corresponding devices for characterizing a region of interest. This can be achieved by performing such an ultrasound scan using an ultrasound probe.

[0059] A scan within the meaning of the present disclosure corresponds to an echographic scan (or ultrasound scan), an echographic (or ultrasound) observation or even an observation phase by echography (or ultrasound), that is to say a phase of emission and reception of ultrasonic waves towards the observed medium, and respectively from said medium. Such a scan comprises the propagation of ultrasonic waves in a region of interest and the recovery in return of echographic echoes (or ultrasonic echoes) emitted by the region of interest. Each scan makes it possible to obtain (or generate) ultrasonic data representative of the region of interest. These data can then be used, for example, to construct images and maps representative of the environment studied, although other uses of ultrasound data are possible.

[0060] It is also possible to combine several types of waves as is practiced with the shear wave elastography mode in which ultrasonic waves are used to measure the speed of movement of shear waves in the observed region of interest.

[0061] As illustrated in Figure 1 in one example, it is possible to use a conventional ultrasound device 1, comprising an ultrasound probe 2, to perform an ultrasound scan of a region of interest M located in the liver of a subject. To do this, the ultrasound probe 2 is driven by the device 1 to emit ultrasound waves W into the region of interest M. In the particular example of ultrasound imaging, the ultrasound echoes received in return from the region of interest are used in particular to generate an ultrasound image 4 representative of the region of interest M.

[0062] However, as illustrated in Figure 1, the appearance, on the ultrasound image 4, of artifacts 6 in the form of dark areas which degrade the quality of the image and hinder or interfere with the ultrasound observation has been observed. These artifacts 6 are measurement defects resulting from internal deformations caused in the subject's liver (in particular at the level of the left lobe) by mechanical activity (or mechanical pressure, or movement), namely that exerted by the heart (located above the diaphragm) and by the abdominal aorta 5 (located behind the left lobe) or by the arteries contained in the hepatic parenchyma. In the example illustrated in Figure 1, the artifact 6 degrading the image 4 results from a movement, or deformation, or mechanical pressure, caused in the region of interest by at least one artery 5 present in the liver.Artery 5 (shown in black) beats according to the subject's cardiac activity, which generates harder elastometry zones because the pulsatility of the vessels generates parasitic shear waves in the region of interest M. Artifact zone 6 corresponds in this example to an area of ​​the liver (hatched area) on the periphery of vessel 5.

[0063] These artifacts 6 degrade the quality of the ultrasound image 4 and hinder ultrasound observation of the liver, which poses a problem in particular for the monitoring and analysis of certain liver conditions, such as diffuse pathologies (fibrosis, steatosis, inflammation, etc.) which do not manifest themselves homogeneously throughout the liver.

[0064] Similar problems arise during the ultrasound observation of other anatomical parts such as a breast or certain soft tissues, or even in other applications such as in the field of monitoring volcanic activity for example, and more generally in all applications where the region of interest is likely to undergo parasitic deformations resulting from involuntary or poorly controlled mechanical pressure.

[0065] The present disclosure proposes to address the problems and constraints previously described by means of an ultrasonic method, and a corresponding control device (or processing device), aimed at characterizing a region of interest by means of an ultrasonic probe. The disclosure provides in particular to coordinate or determine the ultrasonic data to be used for the ultrasonic observation of the region of interest as a function of a mechanical activity occurring in the region of interest. Such mechanical activity (or mechanical pressure) results in a movement, or pressure variation, in the region of interest. By obtaining first ultrasonic data representative of the region of interest, it is advantageously possible to detect such mechanical activity occurring in the region of interest at a given time t1.From this instant t1, a relevant scan period can then be determined, i.e. a period during which the ultrasound scan of the region of interest must be carried out to obtain second quality ultrasound data. In this way, an accurate and reliable ultrasound scan can advantageously be carried out in the region of interest despite the existence of mechanical activity (or movement), occurring in or near the region of interest, which is likely to hinder or impede the ultrasound observation.

[0066] According to particular embodiments, the method thus comprises: - obtaining first ultrasonic data acquired by the ultrasonic probe in origin of a region of interest during an initial ultrasound scan; - detection, from the first ultrasound data, of mechanical activity occurring at a time t1 in the region of interest; - determination of a scan period as a function of time t1; and - determination of second ultrasound data acquired from the region of interest during a second ultrasound scan performed by the ultrasound probe during the scan period.

[0067] Other aspects and advantages of the present disclosure will emerge from the exemplary embodiments described below with reference to the figures mentioned above.

[0068] Methods and devices will now be described according to particular embodiments of the disclosure with joint reference to Figures 2 to 9. Unless otherwise indicated or inconsistent, elements common or similar to several figures bear the same reference signs and have identical or similar characteristics, so that these common elements are generally not described again, for the sake of brevity.

[0069] The terms "first(s)", "second(s)", etc.) are used in this document by arbitrary convention to identify and distinguish different elements (such as modules, data, etc.) implemented in the embodiments described below.

[0070] As previously indicated, the present disclosure relates in particular to an ultrasonic method (or control method) implemented by a control device (or processing device), as well as such a device. Figure 2 schematically represents an ultrasonic system SY1 comprising a control device 10 and a wave emitting device 20, according to exemplary embodiments of the present disclosure.

[0071] The ultrasound emitting device 20 is an ultrasound probe (or echographic probe) configured to emit ultrasound waves W1 towards the region of interest M in response to one or more electrical signals SG1 provided by the control device 10. To do this, the control device 10 may in particular comprise one or more electronic pulsers (more simply called “pulsers”) or amplifiers linear, configured to generate the electrical signal(s) SG1 intended to control the ultrasonic probe 20.

[0072] The ultrasound probe 20 may comprise one or more ultrasound transducers 22 (figure 2), each of them being driven by an electrical signal SG1 delivered by the ultrasound device 10. In response to the received electrical signals SG1, the transducers 22 produce ultrasound waves W1 in the direction of the region of interest M. The transmission of the electrical signals SG1 may be ensured by a link 26 from the pulsers to the transducers 22 of the probe 20.

[0073] The ultrasonic probe 20 is therefore configured to emit ultrasonic waves W1, and possibly also to receive ultrasonic waves W2 from the region of interest M, for example in the form of ultrasonic echoes caused by the waves W1. The nature of the ultrasonic waves W1 and W2 (collectively referred to as W) depends on the configuration of the ultrasonic probe 20, in particular in view of the use made of it.

[0074] According to one example, the control device 10 and the ultrasonic probe 20 are separate elements. According to one variant, all or part of the control device 10 can be implemented in the ultrasonic probe 20. According to one example, the device 10 and the probe 20 form a single device.

[0075] As illustrated in Figure 2, the control device 10 comprises in this example a processor 12 and a memory 14.

[0076] The memory 14 can store in the form of a computer program PG1 instructions defining the steps of the methods described in the present disclosure. In this respect, the memory 14 constitutes a recording medium (or information medium) conforming to particular embodiments, readable by the control device 10, and on which is recorded a computer program PG1 conforming to particular embodiments. This computer program PG1 comprises instructions for executing the steps of an ultrasonic method (or control method) of which particular embodiments are described in the present disclosure. The processor 12 is thus configured to execute the instructions of the computer program PG1 in order to carry out steps of the ultrasonic method.

[0077] Depending on the configuration and the type of computing device considered, the memory 14 may be volatile (such as RAM), non-volatile (such as ROM, flash, EEPROM, etc. or any other storage device and / or computer-readable medium as described below) or a combination of both. The memory 14 may, for example, be managed in DMA mode (for “Direct Memory Access”). The memory 14 used by the control device 10 may, for example, comprise all or part of a graphics card (or video card) memory, this type of memory being in particular capable of processing and / or sending image data that can be used to display one or more images on a display screen (or unit).

[0078] The memory 14 is capable of storing various data that can be used from the control device 10 during the disclosure control method, such as in particular first ultrasound data DT1 obtained during a first ultrasound scan SC1, second ultrasound data DT2 obtained during a second ultrasound scan SC2, and possibly a wave parameter PM1. The nature and function of this data will appear more precisely below in exemplary embodiments of the disclosure method.

[0079] The control device 10 may take the form of various suitable computer means (such as for example workstation, computer, server, etc.) comprising all or part of the elements described above as well as possibly other elements not mentioned. In general, the control device 10 comprises suitable means for implementing the steps of the ultrasonic method as described below in exemplary embodiments.

[0080] As illustrated in Figure 2, each transducer is configured to convert an electrical signal SG1 provided by the control device 10 into ultrasonic waves W (and possibly also vice versa). The transducers 22 can thus be configured to emit waves (or ultrasonic pulses, or ultrasonic beams) W1 into the medium M, which corresponds to an emission operation. These transducer elements 22 can be arranged in any way, for example in a line of transducers, a matrix, or in a network of transducers or any other suitable configuration.

[0081] Note that the transducers 22 may optionally also be configured to receive ultrasonic signals W2 from the medium M in a reception operation, for example in response to the transmitted waves W1, although variants according to which the ultrasonic probe 20 operates only in transmission are also possible.

[0082] The SY1 ultrasound system (Figure 2) may be an ultrasound imaging system, for example in the medical field. The ultrasound images generated by the SY1 system may either be analyzed in real time, for example by a user or an algorithm, and / or an artificial intelligence module, or analyzed later and / or in a different location than the one in which the SY1 system is located.

[0083] The system SY1 may be a medical ultrasound system. Similarly, the transmitter device 20 may be a medical ultrasound probe.

[0084] For example, the system SY1 can be associated with an ultrasound probe 20, in order to study a medium M (figure 2), in particular to collect ultrasound data from such a medium M. The medium M thus observed can be of various natures depending on the case. It can be for example metals, tissues of living beings, in particular human tissues or animal tissues. The observation of a medium M comprising one or more mineral structures for example is also possible (gravel, volcano, mapping of a soil, for example of seabeds, etc.).

[0085] As illustrated in Figure 2, the region of interest M subject to the ultrasonic observation may be subject to various constraints in its environment, including in particular one or more mechanical activities (or pressures) whose origin and characteristics may vary depending on the case as described below in particular examples. Such mechanical activity 30, occurring at a given time tx, may cause deformation or movement within the region of interest M.

[0086] In particular, the mechanical activity 30 likely to occur in the region of interest may be representative of, or depart from, a biological activity of a subject, such as for example a cardiac activity or an arterial activity of the subject.

[0087] The SY1 ultrasound system can be configured for various applications, including acoustics, materials science, medical imaging and / or biomedicine. The SY1 system can be implemented in applications other than ultrasound imaging, for example to characterize a region of interest from collected ultrasound data without generating an ultrasound image.

[0088] Figure 3 schematically represents a non-limiting exemplary embodiment of the system SY1 as previously described with reference to Figure 2, namely in this case an ultrasound imaging system. In this example, the control device 10 is included in the body of a control station, the latter being further provided with a control interface and a display device. The ultrasonic wave emitting device 20 is for example connected in a communicative manner with the control device 10 via a link 26 which here takes the form of a connection cable, although variants are possible where the connection is provided via a wireless link.

[0089] The ultrasound system SY1 can be configured to produce an ultrasound image of various types, for example a B-mode image of the medium M (B-mode image displayed in grayscale), a so-called Doppler image illustrating the movements of fluids in the observed medium, and / or an image showing a mechanical characteristic of the medium (for example elastography image data obtained using shear waves (“ShearWave® Elastography”)). According to one example, the electrical signal SG1 transmitted by the processing device 10 thus causes the emission by the ultrasound probe 20 of compression ultrasonic waves generating shear waves in a medium M.

[0090] As shown in figure 4 according to one embodiment, the processor 12 of the control device 10, controlled by the computer program PG1 (figure 2), can implement an obtaining module MD2, a detection module MD4, a first determination module MD6 and a second determination module MD8.

[0091] More specifically, the obtaining module MD2 is configured to obtain first ultrasound data DT1 acquired by the ultrasound probe 20 from a region of interest M during a first ultrasound scan SC1.

[0092] The detection module MD4 is configured to detect, from the first ultrasound data DT1, a mechanical activity 30 occurring at a time t1 in the region of interest M.

[0093] The first MD6 determination module is configured to determine a scan period PR2 based on time t1.

[0094] The second determination module MD8 is configured to determine second ultrasound data DT2 acquired from the region of interest M during a second ultrasound scan SC2 performed by the ultrasound probe 20 during the scan period PR2.

[0095] The configuration and operation of the MD2-MD4 modules of the control device 10 will appear more precisely in the exemplary embodiments described below with reference to the figures. The MD2-MD4 modules as shown in Figure 4 represent only one non-limiting example of implementation of the invention.

[0096] Generally, for each step of the control method of the present disclosure, the disclosure control device may comprise a corresponding module configured to carry out said step (and vice versa).

[0097] Embodiments of the ultrasonic method (or control method) of the disclosure are now described with reference to Figures 5 to 9. In these examples, the ultrasonic method is implemented by the ultrasonic system SY1 (Figures 2, 3 and 4), and more precisely by the control device 10, as previously described. To do this, the control device 10, cooperating with the ultrasonic probe 20, can execute the computer program PG1.

[0098] During an obtaining step S2 (FIG. 5), the control device 10 obtains first ultrasound data DT1 during a first ultrasound scan SC1. It is assumed in the following that this first scan SC1 is carried out during a first scan period PR1. The first ultrasound data DT1 can be obtained in various ways depending on the case.

[0099] According to one example, the control device 10 controls the ultrasound probe 20 to cause the first ultrasound scan SC1 during a first scan period PR1. To do this, the device 10 sends electrical signals SG1 to the ultrasound probe 20 to trigger the emission of first ultrasound waves W1 towards the region of interest M. In response to these first waves W1, the ultrasound probe 20 receives waves W2 in the form of ultrasound echoes which are converted into electrical signals SG1 sent to the control device 10. From the received signals, the control device 10 can then determine the first ultrasound data DT1 representative of the region of interest M which is the subject of the first scan SC1.

[0100] According to one example, the control device 10 receives the first ultrasound data DT1 from the outside or retrieves this data by reading from a memory accessible by said device 10, for example by consulting the memory 14. For this purpose, the first data DT1 may be recorded in the memory 14 prior to the obtaining step S2. This first ultrasound data DT1 may have been generated beforehand by the control device 10 or by any other appropriate device, for example from signals SG1 delivered by the ultrasound probe 20 during a first ultrasound scan SC1 applied to the region of interest M during a first scan period PR1.

[0101] During a detection step S4 (FIG. 4), the control device 10 detects, from the first ultrasound data DT1, a mechanical activity 30 occurring at a time noted tx. This mechanical activity 30 results, for example, in at least one mechanical pressure, or at least one movement, within the region of interest. The origin and characteristics of this mechanical activity 30 may vary depending on the case. This mechanical activity 30 is likely to disrupt the progress of an ultrasound scan and may in particular degrade the quality of ultrasound data acquired during an ultrasound scan. In particular, such mechanical activity 30 may result in a deformation of, or within, the region of interest M, likely to cause measurement defects (artifacts, etc.) during an ultrasound scan.

[0102] The instant tx can be defined in various ways depending on the case, for example in the form of any temporal indication (or time reference), for example in the form of times and / or dates and / or duration relative to a reference instant such as the start of the first ultrasound scan SC1. This instant tx can correspond to a single instant or can comprise a plurality of instants over time, for example to an instant which is repeated in time such as a periodic or cyclical instant (for example, every N ps from a reference instant, N being a positive number). In the latter case, a plurality of mechanical activities 30 can then be detected in the region of interest M at respective instants tx.

[0103] The mechanical activity 30 may for example be a mechanical disturbance, or any other pressure or movement, which one wishes to take into account in the execution of the method of the disclosure.

[0104] According to one example, the mechanical activity 30 comprises a movement internal to the region of interest M. According to one example, the mechanical activity 30 comprises a movement external to the region of interest M.

[0105] According to one example, the mechanical activity 30 is characterized by, or comprises, one or a plurality of mechanical oscillations occurring in the region of interest M.

[0106] According to one example, the region of interest M is all or part of a subject, such as for example an anatomical part, an organ, tissues, muscle fibers, etc. The subject may be a living being, such as a human or an animal as the case may be, for example a mammal. The mechanical activity 30 thus detected in S4 (figure 5) may then be representative of a biological activity of the subject considered.

[0107] According to one example, the mechanical activity 30 is a biological activity of the subject from one of the following types: a cardiac activity and / or an arterial activity of the subject. Thus, the mechanical activity 30 (or mechanical pressure, or movement) detected in S4 may for example result from a cardiac and / or arterial activity, for example in the form of cardiac impulses. Such cardiac impulses may in particular cause a transient deformation of the arteries in and / or near the region of interest M, and therefore lead to the generation of shear waves which are likely to hinder or disrupt the elastometric measurement of tissues located, in the region of interest, near these arteries.

[0108] Mechanical activity 30 may take the form of an internal and / or external movement of the subject, this movement being able to result from various causes. It may be a voluntary movement of the subject (for example a cough, a respiratory movement, the movement of a limb, etc.) or involuntary (for example a reflex movement of the subject, an internal movement of a tissue, organ, etc. not controllable by the subject).

[0109] According to one example, the mechanical activity 30 detected in S4 (figure 5) corresponds to all or part of a diastolic phase of the subject's cardiac activity. According to one example, the mechanical activity 30 detected in S4 (figure 5) corresponds to all or part of a systolic phase of the subject's cardiac activity. The diastolic phase of the subject's cardiac activity is a periodic phase of rest, itself comprising a contraction relaxation phase and a filling phase. The systolic phase is an active periodic phase of the cardiac cycle corresponding to a contraction of the heart which causes the ejection of blood into the arteries. It is thus possible to detect, from the first DT1 ultrasound data, mechanical disturbances likely to be caused in the region of interest M by the subject's cardiac activity, in particular during the systolic phase.

[0110] According to one example, during the detection step S4 (FIG. 5), the control device 10 determines a wave parameter PM1 from the first ultrasonic data DT1. To do this, the control device 10 can perform processing, or analysis, to determine the wave parameter PM1 as a function of the ultrasonic data DT1. The control device 10 can then compare the wave parameter PM1 thus obtained with a threshold value denoted TH1. A mechanical activity 30 is detected in S4 (FIG. 5) from a result of this comparison between DT1 and TH1.

[0111] According to one example, the wave parameter PM1 is the intensity of ultrasonic signals defined by the first ultrasonic data DT1 obtained in S2 (figure 5). The control device 10 can then compare this parameter PM1 to the threshold value TH1 defining an intensity limit value. If this parameter PM1 reaches or exceeds the threshold value TH1, a mechanical activity 30 is detected in the region of interest M. Variants are however possible.

[0112] According to one example, the wave parameter PM1 comprises a time and / or frequency parameter of ultrasonic signals defined by the first ultrasonic data DT1 obtained in S2 (figure 5). This time parameter characterizes for example a period and / or a frequency of said signals. The control device 10 can then compare this parameter PM1 to the threshold value TH1 defining an intensity limit value. If this parameter PM1 reaches or exceeds the threshold value TH1, a mechanical activity 30 is detected in the region of interest M.

[0113] According to one example, the mechanical activity corresponds to a change in mechanical activity, or to a variation in movement or pressure. If this variation reaches the threshold value TH1, a mechanical activity 30 is detected in the region of interest M.

[0114] During a determination step S6 (figure 5), the control device 10 determines (or defines, or selects) a second scan period PR2 as a function of the instant tx, the moment when the mechanical activity 30 occurs. In other words, this second scan period PR2 is adapted as a function of the instant tx of the mechanical activity 30. As described below, this second scan period PR2 may be distinct from the first scan period PR1 or, alternatively, correspond to a portion of the first scan period PR1.

[0115] According to one example, during the determination step S6 (FIG. 5), the control device 10 selects, as a second scan period PR2, a period meeting a selection criterion CR1 with respect to the instant tx. This criterion CR1 can be adapted as appropriate and can correspond to a single criterion or to a combination of criteria.

[0116] According to one example, the selection criterion CR1 requires that the second scan period PR2 contains the time tx, or that it contains a later time ty which is a function of tx (for example a time ty which occurs with a given delay (for example of the order of 1 ms) or according to a given periodicity with respect to tx).

[0117] According to one example, the selection criterion CR1 requires that the second scan period PR2 does not contain, or excludes, the time tx or a later time ty that is a function of tx (e.g., a time ty that occurs with a given delay or periodicity relative to tx).

[0118] It is thus advantageous to configure the selection criterion CR1 so that the second scan period PR2 corresponds to a relevant period containing, or not containing, an event associated with the mechanical activity 30.

[0119] During a determination step S8 (FIG. 5), the control device 10 determines second ultrasound data DT2 acquired from the region of interest M during a second ultrasound scan SC2 carried out by the ultrasound probe 20 during the second scan period PR2.

[0120] According to one example, the second scan period SC2 comprises one or a plurality of time windows during which the second ultrasound scan SC2 is performed.

[0121] As described below in exemplary embodiments, the second ultrasound scan SC2 may be distinct from the first scan SC1, i.e. another ultrasound scan, subsequent to the first ultrasound scan SC1.

[0122] According to one example, the first ultrasound scan SC1 is stopped (or interrupted) before, or possibly at the same time as, the triggering of the second ultrasound scan SC2. The stopping of the first ultrasound scan SC1 can for example be controlled by the control device 10. Thus, the first and second ultrasound scans SC1 and SC2 can follow one another without overlapping in time. The first ultrasound data DT1 advantageously makes it possible to determine (step S8) a second scan period PR2 appropriate for maximizing the quality of the second ultrasound data DT2 obtained in step S8. Once the instant tx is detected (step S4), it is possible to end the first ultrasound scan SC1 before the triggering of the second ultrasound scan SC2. The most relevant scan period DR2 for limiting the disturbances linked to the mechanical activities detected in the region of interest M can thus advantageously be defined.By preventing the first ultrasound scan SC1 from continuing while the second ultrasound scan SC2 is being performed, it is possible to advantageously limit resource consumption, particularly in terms of computing power and memory, and thus speed up processing.

[0123] According to one example, the second scan period SC2 may comprise a sequence of a plurality of time windows (or periods) during which the second ultrasound scan SC2 is performed. In this case, the first ultrasound scan SC1 may be stopped before, or possibly at the same time as, the start of the sequence of time windows (or periods). By avoiding continuing the first ultrasound scan SC1 during this sequence of time windows, a significant gain in resources and processing speed may be advantageously obtained.

[0124] Alternatively, the second ultrasound scan SC2 may correspond to a portion of the first scan SC1. In other words, the second scan SC2 may be performed by selecting, as second ultrasound data DT2, a portion of the first ultrasound data DT1 so as to exclude at least a portion of the first ultrasound data DT1.

[0125] This determination S8 can thus be carried out so that the second ultrasound data DT2 coincide (or agree) with the second scan period PR2. The second ultrasound data DT2 thus obtained in S8 (figure 5) can thus be acquired during a scan period PR2 relevant to the instant tx marking the mechanical activity 30. In particular, any ultrasound data which could be acquired outside of this second scan period DR2 can be excluded from the second ultrasound data DT2.It is thus advantageously possible to avoid scanning the region of interest M during irrelevant periods of time, for example during periods M including (or not including) the mechanical activity 30 or an equivalent activity, which makes it possible to coordinate the second ultrasound scan SC2 with respect to the mechanical activity 30 and thus to guarantee that the second ultrasound data DT2 are of good quality, in particular in terms of precision and quality according to the intended objective. In the case of an ultrasound imaging application, it is thus advantageously possible to obtain ultrasound images of good quality, increasing the reliability of the measurements derived therefrom.

[0126] The exclusion of any ultrasound data, acquired outside of this second scan period DR2, can be achieved in various ways depending on the case. According to one example, the control device 10 controls the ultrasound probe 20 so that it avoids scanning the region of interest M during irrelevant periods of time (i.e. outside of the second scan period PR2). According to one example, the control device 10 is configured to ignore or exclude any ultrasound data possibly obtained during an irrelevant scan period (i.e. outside of the second scan period PR2). In the latter case, it is advantageous to avoid storing the irrelevant ultrasound data. By avoiding scanning or taking into account ultrasound data during irrelevant periods, it is advantageous to obtain a significant saving in terms of processing cost, resources and time.

[0127] It is for example possible to configure the second scan SC2 so that the second ultrasound data DT2 are acquired during a relevant second scan period PR2 which excludes (takes place outside of) the mechanical activity 30. This second scan period PR2 excludes for example the phase systolic which is likely to disrupt the second SC2 ultrasound scan. This can advantageously ensure that the second DT2 ultrasound data are of good quality, particularly in terms of accuracy and reliability.

[0128] The present disclosure thus advantageously makes it possible to carry out a high-performance ultrasound scan despite movements of (or in) the region of interest M. In particular, it is advantageously possible to obtain precise and reliable DT2 ultrasound data by an ultrasound scan of the region of interest M, despite deformations or movements caused by mechanical activity 30 exerted on and / or in the region of interest M.

[0129] The method and device of the present disclosure can be applied to ultrasound regions M of various natures. According to one example, the region of interest M comprises one of: - all or part of the right and / or left lobe of a liver; - all or part of a breast; and / or - muscle fibers.

[0130] Thanks to the disclosure, it is for example advantageously possible to carry out a good quality ultrasound observation of the right or left lobe of the liver of a subject, while minimizing or avoiding the appearance of artifacts or measurement defects due to heartbeats or the pulsatility of the arteries as previously described.

[0131] For example, it is advantageous to measure elastometry of the liver parenchyma, so that the propagation speed of the shear waves is only taken into account during the diastolic phase of the subject's cardiac activity. Thus, uncontrolled shear waves generated by the arterial pulsatility of the liver vessels are not taken into account.

[0132] Thanks to the disclosure, it is for example advantageously possible to carry out a good quality ultrasound observation of the breast of a subject despite its proximity to the heart and its particularly dense vascular network, while minimizing or avoiding the appearance of artifacts or measurement defects due to heartbeats as previously described.

[0133] By means of the disclosure, it is for example advantageously possible to carry out good quality ultrasound observation of soft tissues, such as tissues adipose tissue, or even muscle fibers, while minimizing or avoiding the appearance of artifacts or measurement defects due to heartbeats as previously described.

[0134] Thanks to the disclosure, it is advantageously possible, for example, to carry out high-quality ultrasound observation of the muscle fibers of a subject, for example in the thigh. Due to the proximity of the thigh to the femoral artery, this area can be particularly difficult to study by ultrasound. The disclosure makes it possible to improve the quality of the images obtained from the second ultrasound data of the second scan.

[0135] Exemplary embodiments of the control method of Figure 5 are now described with reference to Figures 6 and 7.

[0136] Figure 6 represents a first example of implementation of the disclosure control method as previously described with reference to Figure 5. It is assumed by way of example that the control device 10, cooperating with the ultrasonic probe 20, has previously carried out steps S2 and S4 (Figure 5) of the method.

[0137] The control device 10 then performs step S6 of determining (FIG. 5) the second scan period PR2. As illustrated in FIG. 6, it is assumed for example that the mechanical activity 30 was detected (S4, FIG. 5) at the times noted tx during the first ultrasound scan SC1, starting at time t1 and ending at time t2. During step S6 (FIG. 5), the device 10 identifies, as the second scan period PR2, a plurality of time windows (or periods) respecting a selection criterion CR1 with respect to time tx.

[0138] For example, in accordance with the selection criterion CR1, the time windows of the second scan period SC2 are defined so that they do not contain (or, on the contrary, so that they contain) an instant ty which is a function of the instant tx. For example, the instants tx and ty correspond to the same periodic (or cyclic) event, such as for example a phase of the subject's cardiac activity, for example the systolic phase of his cardiac activity. The second scan period SC2 is then defined so that it excludes the systolic phase (for example exclusion of instants ty) or so as to include only the diastolic phase.

[0139] The control device 10 then performs step S8 of determining (FIG. 5) the second ultrasound data DT2 by triggering the second ultrasound scan SC2 during the second scan period PR2, after the first ultrasound scan SC1. In other words, the second ultrasound scan SC2 (and respectively the second scan period PR2) is subsequent to the first ultrasound scan SC1 (and respectively to the first scan period PR1). In this example, the second scan SC2 takes place between the times t3 and t4 (FIG. 6).

[0140] According to one example, the control device 10 can detect in step S4 (FIGS. 5 and 6), from the first ultrasound data DT1, a plurality of mechanical activities 30 occurring at respective times tx in the region of interest M. The control device 10 can then predict, from these times tx, at least one future time ty, also called future theoretical time, during which a said mechanical activity 30 must (or should) occur. The control device 30 can then determine, from the future theoretical time(s) ty, the scan period PR2 during which the second ultrasound scan SC2 is carried out.

[0141] The aforementioned prediction can be carried out by a processing taking as input the first ultrasound data DT1, this processing being able to be adapted as appropriate. Once the instants tx have been determined during the detection step S4, a prediction processing (or calculation) can be carried out from these instants tx to make an estimate of the subsequent instant(s) ty during which it is likely that one or more mechanical activities 30 will occur again in the region of interest. The greater the number of instants tx used, the more reliable the prediction can be. Thanks to this prediction calculation, it is not necessary to continue the first ultrasound scan SC1 while the second ultrasound scan SC2 is being carried out. The first ultrasound scan SC1 can be stopped as soon as the control device 10 has the first ultrasound data DT1 that are sufficiently precise to obtain a quality estimate of the future instants ty.

[0142] The prediction processing (or calculation) mentioned above can be adapted as appropriate. According to one example, the prediction processing comprises, for example, a calculation, from the instants tx, of the average of the intervals separating each pair of two consecutive instants tx, so as to estimate at which instant(s) future mechanical activities will occur or produce.

[0143] According to one example, the prediction processing comprises determining, from the times tx, the largest interval separating two consecutive times. To do this, the time intervals separating each pair of two consecutive times can be determined and the largest interval among them is selected.

[0144] According to one example, the prediction processing comprises determining, from the instants tx, the intervals, between each pair of two consecutive instants tx, whose frequency of occurrence (or number of occurrences) is greater than or equal to a threshold value. A reliable prediction can thus be advantageously made by taking into account only relevant time intervals between the instants tx. Abnormal or unrepresentative time intervals can thus be ignored to improve the prediction result.

[0145] According to an example represented in particular in FIG. 6, a plurality of future theoretical instants ty is predicted from instants tx determined in step S4, in which each instant tx corresponds to a respective mechanical activity 30 occurring during said instant tx. The scan period PR2, determined (step S6) from the plurality of future theoretical instants ty, comprises a sequence of a plurality of successive scan periods spaced in time. The second ultrasound data DT2 are thus obtained from the second ultrasound scan SC2 carried out during this sequence of scan periods.

[0146] For example, the sequence of scan periods forming scan period PR2 is defined so as not to include (i.e. to exclude) future times ty previously determined by prediction.

[0147] If, for example, regular mechanical activity 30 is detected at times tx distributed over time according to a given average time period (or frequency), it is possible to predict at which times future mechanical activities 30 will occur, and thus to adapt accordingly the sequence of scan periods forming the scan period PR2.

[0148] According to one example, the first ultrasound scan SC1 is stopped (or interrupted) before, or possibly at the same time as, the start of the sequence of said a plurality of successive scan periods spaced in time forming the scan period PR2. Thus, the first and second ultrasound scans SC1 and SC2 follow one another without overlapping in time. The first ultrasound data DT1 advantageously makes it possible to determine (step S8) a second scan period PR2 comprising an appropriate sequence of time windows to maximize the quality of the second ultrasound data DT2 obtained in step S8. Once enough times tx are detected (step S4), it is possible to end the first ultrasound scan SC1 before triggering the second ultrasound scan SC2. The most relevant scan period DR2 for limiting disturbances linked to mechanical activities in the region of interest M can thus advantageously be defined.In particular, by avoiding the first ultrasound scan SC1 from continuing while the second ultrasound scan SC2 is being carried out, it is possible to advantageously limit resource consumption, particularly in terms of computing power and memory, and thus speed up processing.

[0149] Thus, the method according to this first example adopts a prospective approach, according to which the first and second scans are different scans which are carried out one after the other: the scan SC1 then the scan SC2. In this way, it is advantageous to avoid carrying out the second ultrasound scan SC2 during periods which are not relevant to the detected mechanical activity 30, for example by excluding periods which contain or do not contain the mechanical activity 30 depending on the desired goal and the nature of the mechanical activity (in particular depending on whether this mechanical activity is a disturbance which one wishes to avoid during the second scan SC2 or on the contrary an event which one wishes to include in the second scan SC2 to take into account its impact on the second ultrasound data DT2).The resources required for carrying out the second SC2 ultrasound scan can be advantageously saved by limiting it to the second PR2 scan period, which excludes one or more irrelevant moments.

[0150] More precisely, during the determination step S8 (figure 5), the device 10 sends for example electrical signals SG1 (figure 2) to cause remission of ultrasonic waves W1 by the ultrasonic probe 20 during the second scan period PR2 determined in S6 (figure 5). The control device 10 receives in return, from the ultrasonic probe 20, of the electrical signals SG1 representative of ultrasonic echoes W2. The second ultrasonic data DT2 are then determined (S6) by processing the signals SG1 thus received.

[0151] According to one example, the control device 10 controls the ultrasound probe 20 so as to scan the region of interest M only during the second scan period DR2. As illustrated in FIG. 6, this second scan period PR2 may for example comprise a plurality of time windows (or periods) during which the second scan SC2 is performed. On the other hand, the ultrasound probe 20 is controlled so as not to scan the region of interest M (deactivation of the scan) during each irrelevant period, called inactive period PR2a, located outside the second scan period PR2 between t3 and t4. In this way, it is advantageous to obtain a significant saving in terms of processing cost, resources and time. For example, the second scan period PR2 may form a sequence of scan periods alternating with inactive periods PR2a between times t3 and t4.

[0152] According to one example, the ultrasound probe 20 scans the region of interest continuously between times t3 and t4 but the control device 10 excludes any ultrasound data acquired outside the second ultrasound period PR2 to take into account only the ultrasound data DT2 obtained during the second period PR2. In this way, it is advantageous to select the most relevant ultrasound data to enable precise and reliable ultrasound observation.

[0153] Figure 7 represents a second example of implementation of the disclosure control method as previously described with reference to Figure 5. It is assumed by way of example that the control device 10, cooperating with the ultrasonic probe 20, has carried out steps S2 and S4 (Figure 5) of the method.

[0154] During the obtaining step S2, the control device 10 records, for example, the first ultrasound data DT1 in the memory 14 to allow subsequent access.

[0155] After steps S2 and S4, the control device 10 performs step S6 of determining (figure 5) the second scan period PR2. As illustrated in figure 7, it is assumed for example that the mechanical activity 30 has been detected (S4, figure 5) at instants noted tx during the first ultrasound scan SC1. During step S6 (figure 5), the device 10 identifies, as a second scan period PR2, a plurality of time windows (or periods) respecting a selection criterion CR1 with respect to the instant tx.

[0156] This second example differs from the first example shown in Figure 6 in that the second scan period PR2 corresponds to one or more sub-parts of the first scan period SC1. In other words, the determination step S6 is carried out by selecting, as the second scan period PR2, one or a plurality of portions of the first scan period PR1, which has the consequence of excluding at least a portion of the first period PR1. In the example illustrated in Figure 7, a plurality of time windows PR2 are selected that meet the selection criterion CR1 with respect to the instants tx detected in S4 (Figure 5).

[0157] For example, in accordance with the selection criterion CR1, the time windows of the second scan period SC2 are defined so that they do not contain the time tx. For example, the time tx corresponds to a periodic (or cyclical) event, such as for example a cardiac phase of the subject, for example the systolic phase of his cardiac activity. The second scan period SC2 is then defined so that it excludes the systolic phase or so that it includes only the diastolic phase.

[0158] Thus, the control device then performs the determination step S8 retrospectively by selecting, as second ultrasonic data DT2, at least a part of the first ultrasonic data DT1 corresponding to the second scan period PR2. In the example illustrated in FIG. 7, the parts of the first ultrasonic data DT1 matching the time windows of the second scan period PR2, i.e. the time windows which do not contain the instant tx, are selected (S8).

[0159] In this way, it is advantageous to avoid performing a new ultrasound scan (as in the first example in Figure 6) and to save the necessary resources by using part of the result of the first ultrasound scan SC1 to obtain the second ultrasound data DT2 of the second scan SC2. Only the relevant part(s) of the first DT1 ultrasound data, i.e. those matching the second scan period PR2 determined in S6, are selected as the second DT2 ultrasound data in S8 (Figures 5 and 7).

[0160] It is thus possible to carry out a single scan SC1 serving as both the first and second scans SC1 and SC2, which makes it possible to limit costs in terms of processing, resources and time. In addition, it is possible to carry out steps S4, S6 and S8 during a later phase in time with respect to step S2 or to repeat steps S4, S6 and S8 a plurality of times with different parameters. For example, it is possible to repeat steps S4, S6 and S8 by modifying certain parameters of the method such as the nature of the mechanical activity 30 sought, the way of searching for this activity in the first ultrasound data DT1 and / or the selection criterion CR1 used, which offers a gain in flexibility.

[0161] Figure 8 represents the implementation of the control method of Figure 5 by the control device 10 according to an exemplary embodiment. In this example, the reference 40 represents the measurement of a wave parameter PM1 determined in step S4 (Figure 5). In accordance with the steps S2 and S4 previously described, the control device 10 detects, from first ultrasound data DT1, a mechanical activity 30 occurring at a time tx in the region of interest M. This mechanical activity 30 results for example in a change in the parameter PM1 relative to a threshold value TH1 (for example an exceeding of the threshold value TH1). As illustrated in Figure 8, the second scan period PR2 is defined so that it does not contain (or excludes) the time tx (or a time ty which is a function of the time tx) during which the mechanical activity 30 occurs.Thus, the second ultrasound scan SC2 is controlled so that the region of interest M is scanned only during the second scan period PR2. In other words, during an ultrasound acquisition phase, the ultrasound probe 20 is active during the second scan period PR2 and remains inactive outside the second scan period PR2.

[0162] Figure 9 represents by way of example an image 50 obtained according to the disclosure control method using the ultrasound probe 20, and more generally the ultrasound system SY1, as previously described. Unlike the example of Figure 1, the method and the system of the disclosure make it possible to obtain an image 50 of good quality without the presence of artifacts due in particular to movements induced by cardiac and arterial activity in or near the region of interest M studied.

[0163] As understood by a person skilled in the art, all the embodiments and variants described above, some of which have been deliberately simplified to facilitate explanations, constitute only non-limiting examples of implementation of the present disclosure. In particular, a person skilled in the art may envisage any adaptation or combination of the embodiments and variants described above, in order to meet a particular need.

[0164] The present disclosure is therefore not limited to the embodiments described above but extends in particular to a treatment method which would include secondary steps without thereby departing from the scope of the present disclosure. The same would apply to a treatment system for implementing such a method.

Claims

CLAIMS 1. An ultrasonic method using an ultrasonic probe (20), the method comprising: - obtaining (S2) first ultrasound data (DT1) from a region of interest (M) during a first ultrasound scan (SC1); - detection (S4), from the first ultrasonic data, of a mechanical activity (30) occurring at an instant tx in the region of interest; - determination (S6) of a scan period (DR2) as a function of the instant tx; and - determination (S8) of second ultrasound data (DT2) acquired from the region of interest during a second ultrasound scan (DT2) during the scan period (DR2).

2. Method according to claim 1, in which the region of interest (M) is all or part of a subject, the mechanical activity (30) being representative of a biological activity of the subject.

3. The method of claim 2, wherein the biological activity of the subject comprises at least one of cardiac activity or arterial activity of the subject.

4. Method according to any one of the preceding claims, in which the mechanical activity (30) corresponds to all or part of a diastolic or systolic phase of the subject's cardiac activity.

5. Method according to any one of the preceding claims, in which the detection (S4) of a mechanical activity comprises: - determination of a wave parameter (PM1) from the first ultrasonic data (DT1); - comparison of said wave parameter with a threshold value (TH1); and - detection of a mechanical activity (30) from a result of said comparison.

6. Method according to any one of the preceding claims, wherein the determination (S6) of a scan period comprises: - selection, as a scan period (DR2), of a period respecting a selection criterion (CR1) in relation to the instant tx.

7. The method of claim 6, wherein determining (S6) the scan period comprises any one of: - selection, as scan period, of a period comprising the instant tx or an instant ty depending on tx; and - selection, as scan period, of a period distinct from the instant tx or an instant ty depending on tx.

8. Method according to any one of the preceding claims, in which the second ultrasound data (DT2) coincide with the scan period (DR2).

9. Method according to any one of the preceding claims, wherein the determination (S8) of the second ultrasonic data is carried out by triggering the second ultrasonic scan (SC2) during the scanning period, after the first ultrasonic scan (SC1), the second ultrasonic data (DT2) being distinct from the first ultrasonic data (DT1).

10. The method of claim 9, wherein performing the second ultrasound scan comprises: - sending signals (SG1) to the ultrasonic probe (20) to cause the emission of ultrasonic or shear waves only during the scan period.

11. Method according to any one of the preceding claims, in which the first ultrasound scan (SC1) is stopped before, or at the same time as, the triggering of the second ultrasound scan (SC2).

12. Method according to any one of the preceding claims, comprising: - detecting, from the first ultrasonic data, a plurality of mechanical activities (30) occurring at respective times tx in the region of interest; - prediction, from the respective instants ty, of at least one future theoretical instant tx during which a said mechanical activity must occur; and - determination, from said at least one future theoretical instant ty, of the scan period.

13. The method of claim 12, wherein a plurality of future theoretical instants ty are predicted from the respective instants tx, wherein the scan period determined from the plurality of future theoretical instants ty comprises a sequence of a plurality of successive and time-spaced scan periods.

14. The method of claim 13, wherein the first ultrasound scan (SC1) is stopped before, or at the same time as, the start of the sequence of said plurality of successive and time-spaced scan periods.

15. Method according to any one of claims 1 to 8, wherein the determination (S8) of the second ultrasonic data is carried out retrospectively by selecting, as second ultrasonic data (DT2), a part of the first ultrasonic data (DT1).

16. Method according to any one of the preceding claims, in which the region of interest (M) comprises one of: - all or part of the right or left lobe of a liver; - all or part of a breast; and - muscle fibers.

17. Method according to any one of the preceding claims, wherein said method is applied to medical ultrasound imaging.

18. Computer program (PG1) comprising instructions for executing the steps of a method according to any one of the preceding claims when said program is executed by a computer.

19. Control device (10) capable of cooperating with an ultrasonic probe (20), said device comprising: - an obtaining module (MD2) configured to obtain first ultrasound data (DT1) acquired by the ultrasound probe from a region of interest (M) during a first ultrasound scan (SC1); - a detection module (MD4) configured to detect, from the first ultrasonic data, a mechanical activity (30) occurring at a time tx in the region of interest; - a first determination module (MD6) configured to determine a scan period (DR2) as a function of the instant tx; and - a second determination module (MD8) configured to determine second ultrasound data (DT2) acquired from the region of interest during a second ultrasound scan (SC2) during the scan period.

Images