OPHTHALMIC ULTRASOUND PROCEDURE

Abstract

The invention relates to a method of ophthalmic ultrasound in which: - the ultrasound probe is positioned (S1) relative to an eye, - the ultrasound probe emits and receives ultrasound waves (S21), generates data, and transmits the image data to the automated data processing unit (S22), - the inertial measurement unit determines (S23) positioning data of the ultrasound probe and transmits said positioning data to the automated data processing unit, - the automated data processing unit selects (S24) a predetermined spatial configuration from a finite set of predetermined spatial configurations, - the automated data processing unit determines (S3) display data associating the image data with a visual reference comprising visual indicators representative of the previously selected predetermined spatial configuration.- The automated data processing unit transmits the display data to the screen, and the screen displays the display data (S4).

Description

1. OPHTHALMIC ULTRASOUND METHOD TECHNICAL FIELD OF THE INVENTION The present invention belongs to the field of ophthalmic equipment. More specifically, the invention relates to an ophthalmic ultrasound system enabling the determination of the orientation of the acquired images relative to the imaged eye. Ophthalmic ultrasound involves acquiring an image of the eye using an ultrasound probe that emits a beam of sound waves. The ultrasound probe is positioned close to the eye, typically in contact with it, and emits ultrasound waves that propagate through the eye. These waves pass through the internal structures of the eye, such as the lens, vitreous humor, and retina, and are partially reflected by these structures. The reflected ultrasound waves are captured and recorded by the probe to produce images of the eye. The ultrasound beam emitted by an ophthalmic ultrasound probe extends along a plane, so the acquired image is a cross-sectional representation of the eye along this plane. Because the plane of propagation of the ultrasound waves depends on the position and orientation of the probe, the portion of the eye that is imaged also depends on the probe's position and orientation at the time of acquisition. Thus,Depending on the type of examination being performed, different positions and orientations are used to image the area of ​​interest in the eye. However, because the eye is generally spherical and fairly homogeneous, its various components offer few reference points for determining the imaged area from the acquired image alone. An image is only fully usable when the imaged area of ​​the eye it represents is known, which is directly linked to the position and orientation of the probe. Therefore, the operator acquiring the images must manually indicate what each image corresponds to, or the probe's position, which is time-consuming and carries a risk of error. Furthermore, during video recording, the probe's position can change.and it is sometimes difficult for the operator to correctly interpret these 3059224 2 changes in position given the difficulties in locating them in the images. A series of images can then only correspond to one or two positions of the ultrasound probe, which the user must keep track of, typically by manually annotating the images. 5 PRESENTATION OF THE INVENTION The invention aims to provide a method and a system that makes it possible to associate each image acquired during an ophthalmic ultrasound with the positioning of the probe during that acquisition. To this end,An ophthalmic ultrasound method is proposed, implemented using an ophthalmic ultrasound system comprising: - an ultrasound probe configured to be positioned relative to an eye 15 and to emit and receive ultrasound waves propagating in the eye in order to generate image data defining at least one image from the received ultrasound waves, - an inertial measurement unit attached to the ultrasound probe and incorporating at least one gyroscope and at least one accelerometer, said inertial measurement unit being 20 adapted to measure at least one rotation around an axis and to measure at least one acceleration along an axis, the measurement of rotation and the measurement of acceleration forming positioning data for the ultrasound probe, - an automated data processing unit comprising at least one processor and one memory,connected to the ultrasound probe and the inertial measurement unit 25 and configured to receive image data from the ultrasound probe and positioning data from the inertial measurement unit of the ultrasound probe for each image defined by the image data, - a screen configured to receive image data from the automated data processing unit and to display said data, 30 said method comprising the steps according to which: - the ultrasound probe is positioned relative to an eye, - the ultrasound probe emits and receives ultrasound waves propagating in the eye, generates image data from the received ultrasound waves, and transmits the image data to the automated data processing unit,3059224 3 - The inertial measurement unit determines positioning data for the ultrasonic probe and transmits said positioning data to the automated data processing unit for each image defined by the image data. - From the positioning data of the ultrasonic probe, the automated data processing unit selects, for each image defined by the image data, a predetermined spatial configuration from a finite set of predetermined spatial configurations. - The automated data processing unit determines display data associating the image data with a visual reference comprising visual indicators representative of the previously selected predetermined spatial configuration. - The automated data processing unit transmits the display data to the screen, and the screen displays the display data. 15 The method is advantageously complemented by the following features:taken alone or in any technically possible combination thereof: - the predetermined spatial configurations define a position of the ultrasound probe and an orientation of the ultrasound probe relative to a spatial reference frame corresponding to the configuration of an eye; 20 - each predetermined spatial configuration corresponds at least to: - an orientation of the probe relative to the eye, said orientation corresponding to the incidence of an acquisition plane of the ultrasound probe on the eye relative to an interface between an iris and a sclera, - a position of the probe relative to said eye,said position corresponding to 25 an angle of rotation of the acquisition plane of the ultrasound probe on the eye around the pupil; - at least certain predetermined spatial configurations further correspond to an inclination of the acquisition plane of the ultrasound probe with respect to the surface of the eye; 30 - the orientation of the ultrasound probe is chosen from: - a transverse orientation, in which the acquisition plane of the ultrasound probe on the eye extends on the surface of the eye tangentially to the interface between the iris and the sclera of the eye, 3059224 4 - a longitudinal orientation, in which the acquisition plane of the ultrasound probe on the eye extends on the surface of the sclera radially with respect to the interface between the iris and the sclera of the eye, - an axial orientation,in which the acquisition plane of the ultrasound probe 5 on the eye extends radially across the surface of the iris and pupil relative to the interface between the iris and the sclera of the eye; - each predetermined spatial configuration of the finite set of predetermined spatial configurations corresponds to a predetermined positioning of the ultrasound probe, and the automated data processing unit selects the 10 predetermined spatial configuration that presents the predetermined positioning closest to the probe positioning defined by the positioning data; - the visual reference comprises a surface bearing markings distributed over said surface by rotational symmetry around a center of said surface,and a visual indicator representing the probe's position is placed at the location of a mark whose location on the surface corresponds to the position of the ultrasonic probe relative to the eye in the previously selected predetermined spatial configuration; - the method includes, in addition to a preliminary calibration step in which the ultrasonic probe is positioned relative to the eye at a predefined position and orientation, and a calibration command is sent by a user to the automated data processing unit,The positioning data of the ultrasound probe is then determined from the movements of the ultrasound probe relative to the predefined position and orientation; - the automated data processing unit includes an input interface 25 for information, and a user inputs a portion of the probe's positioning data concerning the orientation of the ultrasound probe relative to the eye. - to determine the display data, the automated data processing unit merges an image defined by the image data with the visual reference by superimposing said visual reference over a portion of the image. 30 The invention also relates to an ophthalmic ultrasound system comprising: - an ultrasound probe configured to be positioned relative to an eye and to emit and receive ultrasound waves propagating within the eye in order to generate image data defining at least one image,3059224 5 - an inertial measurement unit (IMU) attached to the ultrasonic probe and incorporating at least one gyroscope and at least one accelerometer, said IMU being adapted to measure at least one rotation about an axis and to measure at least one acceleration along an axis, the rotation measurement and the acceleration measurements forming positioning data for the ultrasonic probe, - an automated data processing unit comprising at least one processor and one memory, connected to the ultrasonic probe and the IMU and configured to receive image data from the ultrasonic probe and positioning data for the ultrasonic probe from the IMU for each image defined by the image data, - a display configured to receive display data from the automated data processing unit and to display said data, the automated data processing unit being configured to,In response to the reception of image and positioning data from the ultrasonic probe: - select, for each image defined by the image data, from the ultrasonic probe's positioning data for said image, a predetermined spatial configuration from a finite set of predetermined spatial configurations; - associate the image with a visual marker comprising visual indicators representative of the previously selected predetermined spatial configuration; - transmit display data to the screen comprising the image and the visual marker, so that the screen simultaneously displays the image and the visual marker. Preferably,The ophthalmic ultrasound system is configured to implement the method according to the invention. The invention also relates to a computer program product comprising program code instructions recorded on a non-volatile medium usable in a computer for executing processing steps of the method according to any one of the preceding claims, when said program is executed on a computer. PRESENTATION OF FIGURES The invention will be better understood from the following description, which relates to 35 embodiments and variants of the present invention, given by way of non-limiting examples and explained with reference to the accompanying schematic drawings, in which: - Figure 1 shows a schematic diagram showing implementation steps of a possible embodiment of the invention, - Figures 2a, 2b, 3a, 3b, 4a,Figures 4b illustrate different spatial configurations of the probe relative to a human right eye; Figures 5a, 5b, 5c, and 5d show examples of visual cues for different spatial configurations of the probe; Figure 6 shows an ultrasound image with a visual cue for the positioning of the ultrasound probe corresponding to the spatial configuration of the probe at the time of image acquisition. DETAILED DESCRIPTION 15 The implementation of the ophthalmic ultrasound procedure uses an ophthalmic ultrasound system. Such a system includes an ultrasound probe configured to be positioned relative to an eye and to emit and receive ultrasound waves propagating within the eye in order to generate image data from the received ultrasound waves. The ultrasound probe typically includes a plurality of ultrasound transducers, for example, piezoelectric,configured to emit ultrasound waves that propagate through the eye along a propagation plane. These ultrasound waves typically have a frequency between 10 and 100 MHz. Ultrasound waves reflected by the internal structures of the eye also propagate along this plane, which is therefore also an acquisition plane for the ultrasound probe, since image data 25 are generated from these received ultrasound waves. The system also includes an inertial measurement unit (IMU) attached to the ultrasound probe. Typically, this IMU is incorporated within the housing containing the ultrasound transducers of the ultrasound probe, and can therefore be considered 30 as part of said ultrasound probe. The IMU is configured to determine positioning data for the ultrasound probe. This positioning data is representative of the probe's position relative to the eye.and in particular with respect to the central axis of the eye passing through the pupil, and commonly referred to as the apex of the eye. For this purpose, the inertial measurement unit (IMU) is adapted to measure at least one rotation (angular velocity or angular position) about an axis and to measure at least one acceleration along an axis. To do this, the IMU includes at least one gyroscope and at least one accelerometer. The rotation measurement and the acceleration measurement form positioning data for the ultrasonic probe. Preferably, the IMU is adapted to measure one rotation about each of three non-collinear axes and to measure one acceleration along each of the three non-collinear axes.These rotation and acceleration measurements then form the positioning data of the ultrasonic probe. 10 The system also includes an automated data processing unit comprising at least one processor and memory. This is typically a computer, comprising the typical components of a computer. The automated data processing unit is connected to the ultrasonic probe and the inertial measurement unit 15 and is configured to receive image data from the ultrasonic probe and positioning data from the inertial measurement unit of the ultrasonic probe. Furthermore, the system also includes a display configured to receive display data from the automated data processing unit and 20 to display said data. The system may also include various accessories such as data input devices, such as a keyboard or touchscreen. With reference to Figure 1,The implementation of the ophthalmic ultrasound procedure includes a first step S1 in which the ultrasound probe is positioned 25° relative to an eye, in order to emit and receive ultrasound waves propagating within that eye. The ultrasound probe may be placed in contact with the eye, i.e., against the cornea or sclera, possibly covered with a gel. A pocket of water may also be placed between the ultrasound probe and the eye. The ultrasound probe may also be immersed in a liquid 30° contained in a cup open against the eye, the liquid serving as an intermediate propagation medium between the ultrasound probe and the eye. This description, without limitation, applies to cases where the probe is placed in contact with the eye. 3059224 8 Once positioned,The ultrasound probe emits and receives ultrasound waves (step S21) that propagate through the eye. The ultrasound probe generates image data from the received ultrasound waves (step S22) and transmits this image data to the automated data processing unit. The screen can display a 5-image derived from this image data in real time, notably to assist the user in positioning the ultrasound probe. Figures 2a, 2b, 3a, 3b, 4a, and 4b illustrate different spatial configurations of the ultrasound probe relative to a right eye. A human eye 1 comprises several components. Among the components of the eye 1 that are visible from the front (in Figures 2b, 3b, and 4b), the main ones are a pupil 2, surrounded by an iris 4, which is surrounded by the sclera 6 (the white of the eye). The pupil 2 and the iris 4 are visible through the cornea 8. As shown in Figures 2a, 3a and 4a,Ophthalmic ultrasound allows the acquisition of images of internal components of the eye 1, such as the vitreous humor 12 or 15, the retina 13 (or any other structures of the eye, whether in the anterior and / or posterior segment, orbital, such as the muscles and the optic nerve). An ultrasound probe 10 is placed against the surface of the eye 1 or opposite the surface of the eye using an immersion technique. The ultrasound probe has a mark 14 to help the operator position it, in particular by providing a rotation reference point 20 for a cylindrical probe. Since these are the elements visible from the outside, the position and orientation of the ultrasonic probe 10 are determined in particular with respect to the pupil 2 and the iris 4. In the example illustrated by Figure 2a, the ultrasonic probe 10 has a transverse orientation 25, generally indicated by the letter "T", in which the plane of propagation of the ultrasonic waves,Therefore, the acquisition plane 16 of the ultrasound probe 10 extends inside the eye 1 from a position tangential to the interface between the iris 4 and the sclera 6. In this transverse orientation, the ultrasound probe 10 can assume a multitude of positions through rotational symmetry around the center of the pupil, traversing the boundary between the iris 4 and the sclera 6. These positions can, however, be limited to the main ones, illustrated in Figure 2b, namely: - two vertical positions, one on each side of the iris 4, marked by V in Figure 2b, in which the beam extends along a vertical plane (relative to the eye of a person in a standing position), - two horizontal positions, one above the iris 4 and the other below the iris 4, marked by H in Figure 2b, in which the beam extends along a horizontal plane (relative to the eye of a person in a standing position),- four oblique positions, marked by 0 in Figure 2b, corresponding to 5 of the intermediate positions between the two vertical positions V and the two horizontal positions H. In the example illustrated in Figure 3a, the ultrasound probe 10 has a longitudinal orientation, generally indicated by the letter "L", in which the plane of propagation of the ultrasound waves, and therefore the acquisition plane of the ultrasound probe 10, extends radially inside the eye from the interface between the iris and the sclera. In this longitudinal orientation, the ultrasound probe 10 can assume a multitude of positions by rotational symmetry around the center of the pupil, traversing the boundary between the iris and the sclera. These positions can, however, be limited to the main positions illustrated in Figure 3b, namely: - two horizontal positions, one on each side of the iris, marked by H in figure 3b,in which the beam extends along a horizontal plane (relative to the eye of a person in a standing position), - two vertical positions, one at the top of the iris 4 and the other at the bottom of the iris 4, 20 marked by V in Figure 3b, in which the beam extends along a vertical plane (relative to the eye of a person in a standing position), - four oblique positions, marked by 0 in Figure 3b, corresponding to intermediate positions between the two vertical positions V and the two horizontal positions H. 25 In the example illustrated by Figure 4a, the ultrasound probe 10 has an axial orientation, generally indicated by the letter "A", in which the plane of propagation of the ultrasound waves, and therefore the acquisition plane 16 of the ultrasound probe 10, includes the optical axis formed by the pupil 2 and the optic nerve,and extends 30° inside the eye 1. The propagation plane enters the eye 1 by passing through the iris 4 and the pupil 2. In this axial orientation, the ultrasonic probe 10 can assume a multitude of positions by rotational symmetry around the center of the pupil 2. These positions can, however, be limited to the main positions, illustrated in Figure 4b, namely: - a horizontal position, marked by H in Figure 4b, in which the beam extends along a horizontal plane (relative to the eye of a person in a standing position), - a vertical position, marked by V in Figure 4b, in which the beam extends along a vertical plane (relative to the eye of a person in a standing position), - two oblique positions, marked by O in Figure 4b, corresponding to intermediate positions between the vertical position V and the horizontal position H. Simultaneously with the image acquisition by the ultrasound probe,The inertial measurement unit determines positioning data for the ultrasonic probe (step S23) and transmits this positioning data to the automated data processing unit. This positioning data includes at least one rotation measurement about an axis and one acceleration measurement along an axis. Preferably, the positioning data includes one rotation measurement about each of three non-collinear axes and one acceleration measurement along each of three non-collinear axes. It should be noted that the positioning data can also be data derived from these rotation and acceleration measurements, for example, spatial coordinates relative to a reference frame, deduced from these measurements.or 20 angles derived from angular velocity measurements. Positioning data reflects the actual spatial configuration of the ultrasound probe relative to the eye at the time of image data acquisition. Positioning data can take on a large number of values, since the actual spatial configuration can exhibit a large number of variations, even when observing the same area of ​​the eye. In fact, images acquired by ophthalmic ultrasound depend on the spatial configuration of the ultrasound probe relative to an eye when the images are acquired. Therefore, the spatial configuration of the ultrasound probe relative to an eye when said ultrasound probe is positioned relative to the eye depends on the area of ​​the eye that the user seeks to image, and thus varies between examinations. When examining an eye,The user of the ultrasound probe modifies its spatial configuration to image the areas to be examined of the eye, based in particular on the image displayed on the screen. The positioning of the ultrasound probe is done by a human operator. This is therefore an imperfect positioning compared to an ideal one. Moreover, the shape of an eye varies from person to person, so that to observe the same area of ​​the eye, the positioning of the ultrasound probe will differ from one person to another. However, it is the images acquired and displayed on the screen that dictate the exact positioning of the ultrasound probe by the user. As a result, a theoretical spatial configuration of the ultrasound probe can translate into different positioning data. In order to facilitate the use of the knowledge of the ultrasound probe's positioning obtained from the inertial measurement unit,The automated data processing unit selects (step S24) a predetermined spatial configuration from a finite set of predetermined spatial configurations, based on the positioning data of the ultrasonic probe 10 transmitted by the inertial measurement unit. 15 These predetermined spatial configurations define a position of the ultrasonic probe and an orientation of the ultrasonic probe relative to a spatial reference frame corresponding to the configuration of an eye. Thus, each predetermined spatial configuration in the finite set of predetermined spatial configurations 20 corresponds to a predetermined positioning of the ultrasonic probe relative to an eye. Each predetermined spatial configuration corresponds at least to: - an orientation of the ultrasonic probe 10 relative to eye 1,said 25 orientation corresponding to the incidence of an acquisition plane 16 of the ultrasound probe 10 on the eye 1 with respect to an interface between an iris 4 and a sclera 6, - a position of the ultrasound probe 10 with respect to said eye 1, said position corresponding to an angle of rotation of the acquisition plane 16 of the ultrasound probe 10 on the eye 1 around the pupil 2. 30 Figures 2b, 3b, and 4b present 20 examples of predetermined spatial configurations, previously described. At least some predetermined spatial configurations can also take into account an inclination of the acquisition plane 16 of the ultrasound probe 10 by 35 relative to the surface of the eye 1. Indeed, the orientation and position of the ultrasound probe 3059224 12 relative to the eye 1 essentially indicates how the ultrasound probe 10 is arranged on the surface of the eye,and thus locates the incidence of the acquisition plane 16 of the ultrasound probe on the eye. However, for the same positioning, the inclination of the ultrasound probe 10 changes the inclination of the plane of propagation of the ultrasound waves in the eye, and therefore of the acquisition field 16 of the ultrasound probe. As a result, the inclination of the ultrasound probe 10 influences the depth examined in the eye 1. In order to account for this effect, the positioning data can also be used to extract information on the inclination of the ultrasound probe 10 relative to the surface of the eye 1.which 10 corresponds to the emission surface of the ultrasonic waves since the ultrasonic probe 10 is positioned relative to the eye 1. The automated data processing unit selects the predetermined spatial configuration that presents the predetermined positioning closest to the 15 positioning of the ultrasonic probe 10 defined by the positioning data. For example, when the ultrasonic probe 10 transmits to the automated data processing unit positioning data corresponding to rotation angles around three non-aligned axes and coordinates relative to the three non-aligned axes, the automated data processing unit compares these angles and coordinates with angles and coordinates associated with each predetermined positioning corresponding to the different predetermined spatial configurations, and, based on a criterion of similarity or dissimilarity,selects the predetermined spatial configuration with the highest similarity or lowest dissimilarity. For example, this might involve determining norms for the 25 differences (Euclidean norms, absolute distance, etc.) between angles and between coordinates, and selecting the predetermined spatial configuration for which these norms (or a combination thereof) are minimal. It is understood that the positioning data can be measurements of position, velocity, or acceleration, and that the automated data processing unit 30 determines the rotation angles and coordinates. It is also possible for a user to input some of the positioning data for the ultrasonic probe 10 concerning the orientation of the ultrasonic probe relative to the eye, or to preselect certain predetermined spatial configurations 35. For example,The user can indicate to the automated processing unit (3059224 13) the orientation (transverse, longitudinal, or axial) of the ultrasound probe in which a series of images will be acquired. In this way, only predetermined spatial configurations corresponding to this specific orientation will be taken into account during selection, which is then based on the probe's position (5) and possibly the depth. In this regard, the automated data processing unit includes an input interface for the user to enter some of the probe's positioning data concerning the ultrasound probe's orientation relative to the eye. Since the determination of the positioning data relies on an inertial measurement unit (IMU), it may be advantageous to include a calibration step prior to acquiring a series of images.in order to improve the accuracy of determining the positioning of the ultrasound probe. Preferably, the method therefore further includes a preliminary calibration step in which the ultrasound probe 15 is positioned relative to the eye at a predefined position and orientation, and a calibration command is sent by a user to the automated data processing unit, the positioning data of the ultrasound probe then being determined from the movements of the ultrasound probe relative to the predefined position and orientation. The calibration command 20 can be initiated by any control means, such as pressing a foot pedal, a trigger, or a button. Preferably, the prescribed positioning of the probe in this calibration step corresponds to a spatial configuration that is particularly easy to locate on the eye 1,such as a horizontal or vertical position aligned with the vertical axis of the eye 1 of a person in a standing position or 25 other, for example the pupil or the apex of the boundary between the sclera 6 and the iris 4. The automated data processing unit determines display data (step S3) associating the image data with a visual marker comprising visual indicators representative of the previously selected predetermined spatial configuration 30. Preferably, the visual marker has a pattern common to several predetermined spatial configurations, and the visual indicators are positioned at locations that are functions of the selected predetermined spatial configuration. Figures 5a, 5b, 5c, and 5d show examples of visual markers 20 for 35 different spatial configurations of the probe. The visual markers 20 in Figures 5a, 5b, and 5c have a common pattern, comprising a circular surface 21,bearing marks 22 distributed over said surface by rotational symmetry around a center 23 of said surface 21. The common pattern thus has the shape of a clock face. A visual indicator 24 representing the position of the probe 5 is located at the location of a mark 22 whose location in the surface corresponds to the position of the probe relative to the eye 1 in the previously selected predetermined spatial configuration. In addition, the common pattern may have locations 25 to indicate the orientation of the ultrasonic probe 10, by applying a light signal 26 to one of these locations, conveniently 10 identified by a distinctive sign such as a letter. Furthermore, a mark 27 on the visual indicator 24 may be present to indicate the direction of the ultrasonic probe 10, corresponding to the mark 14 present on the ultrasonic probe 10. Thus,Figure 5a shows a visual reference point corresponding to a transverse orientation 15, as indicated by the light signal 26 present at location 25 corresponding to the letter "T", and a vertical left-hand position of the ultrasonic probe, as shown by the visual indicator 24 positioned at "9 o'clock" and oriented vertically on the surface 21. This predetermined spatial configuration can be referred to as "T9" or "T9:00" or "Temporal" (for a right eye). Figure 5b shows a visual reference point corresponding to a longitudinal orientation, as indicated by the light signal 26 present at location 25 corresponding to the letter "L", and a horizontal left-hand position of the ultrasonic probe.as shown by indicator 24 positioned at "9 o'clock" and oriented horizontally on surface 21. This predetermined spatial configuration can be referred to as 25 being "L9" or - L9:00" or - Temporal" (for a right eye). Figure 5c shows a visual marker corresponding to an axial orientation, as indicated by the light signal 26 present at location 25 corresponding to the letter "A", and a horizontal ultrasonic probe position centered on the probe, as shown by visual indicator 24 positioned in the center of surface 21 and oriented horizontally on surface 21. Mark 27,directed to the left (towards mark 3) shows that mark 14 of the ultrasound probe 10 was directed to the left. This predetermined spatial configuration can be referred to as "A3" or "A3:00" or "Nasal" (for a right eye). Figure 5d corresponds to another type of visual marker 30 (which symbolizes the area of ​​the eye 1 imaged by the ultrasound probe 10 and not the position of the ultrasound probe 10 on the eye) in which a schematic representation 31 of a cross-sectional eye includes marks 32 corresponding to different depths of the eye, and a visual marker 33 is positioned at mark 32 corresponding to the inclination of the ultrasound probe 10 in the predetermined spatial configuration. In the illustrated case, the position of the visual marker 33 is at the top of the cross-section.The letter "E" (for equator) indicates that the inclination of the ultrasound probe 10 corresponds to an acquisition plane 16 visualizing the equatorial zone of the eye 1. This type of visual reference can 10 be used, in particular, to complement a visual reference as illustrated in Figures 5a, 5b, and 5c. The display data associates the image data with a visual reference determined from the positioning data. Preferably, to determine the display data 15, the automated data processing unit can fuse an image defined by the image data with the visual reference by superimposing said visual reference over a portion of the image. Figure 6 illustrates an example of such a combination resulting from the superimposition of an image 40 acquired with an ultrasound probe 10 in an axial orientation and a horizontal position oriented to the left 20 (corresponding to -A9", -A9:00", or Axial Temporal).as shown by the visual marker 41 embedded in image 40. This image data is transmitted to the screen, which then displays it (step S23). The screen display then takes on an appearance such as that illustrated in Figure 6.25. In a typical case, a series of images is acquired, like a video sequence, and the user subsequently chooses the images they want to keep for examination. For each of these images, the positioning data is determined, the corresponding predetermined spatial configurations are determined, and the display data associates the image data of each image with a visual marker corresponding to the predetermined spatial configuration selected for that image. Thanks to the visual marker present with each image, the user knows which probe positioning the image corresponds to.and therefore knows which region of the eye is being observed. 35 3059224 16 This allows the acquisition of a series of images corresponding to several positions of the ultrasound probe, and then their selection by knowing, for each image, the position of the ultrasound probe corresponding to that image. This simplifies the examination of the eye, since previously, the user had to manually keep track of the probe's position and could not move the probe much during the examination, at the risk of no longer being able to identify the images. Furthermore, the automatic placement of the marker eliminates the risk of notation errors. The invention is not limited to the embodiment described and shown in the attached Figures 10. Modifications remain possible, particularly with regard to the construction of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims

Demands 1. Ophthalmic ultrasound procedure implemented using an ophthalmic ultrasound system comprising: - an ultrasonic probe (10) configured to be positioned relative to an eye (1) and to emit and receive ultrasonic waves propagating in the eye in order to generate image data defining at least one image from the received ultrasonic waves, - an inertial measurement unit attached to the ultrasonic probe and combining at least one gyroscope and at least one accelerometer, said inertial measurement unit being adapted to measure at least one rotation around an axis and to measure at least one acceleration along an axis, the measurement of rotation and the measurement of acceleration forming positioning data for the ultrasonic probe (10), - an automated data processing unit comprising at least one processor and one memory, connected to the ultrasonic probe and the inertial measurement unit and configured to receive image data from the ultrasonic probe and positioning data from the inertial measurement unit for the ultrasonic probe for each image defined by the image data, - a screen configured to receive display data from the automated data processing unit and to display said data, said method comprising the steps according to which: - the ultrasonic probe (10) is positioned relative (S1) to an eye (1), - The ultrasound probe emits and receives ultrasonic waves (S21) propagating in the eye, generates image data (S22) from the received ultrasonic waves, and transmits the image data to the automated data processing unit, - The inertial measurement unit (S23) determines positioning data for the ultrasonic probe and transmits said positioning data to the automated data processing unit for each image defined by the image data, - from the positioning data of the ultrasonic probe, the automated data processing unit selects (S24) for each image defined by the image data a predetermined spatial configuration from a finite set of predetermined spatial configurations, the spatial configurations predetermined values ​​defining a position of the ultrasonic probe (10) and an orientation of the ultrasonic probe (10) relative to a spatial reference frame corresponding to the configuration of an eye, - the automated data processing unit determines (S3) display data associating image data with a visual reference (20, 30) comprising visual indicators (24, 33) representative of the previously selected predetermined spatial configuration, the visual reference (20, 30) comprising a surface (21) bearing marks (22) distributed over said surface by rotational symmetry around a center (23) of said surface, and a visual indicator (24) representative of the position of the probe taking place at the location of a mark (22) whose location in the surface corresponds to the position of the ultrasonic probe (10) relative to the eye in the previously selected predetermined spatial configuration, - the automated data processing unit transmits the display data to the screen and the screen displays the display data (S4).

2. A method according to claim 1, wherein each predetermined spatial configuration corresponds at least to: - an orientation of the probe relative to the eye, said orientation corresponding to the incidence of an acquisition plane (16) of the ultrasound probe (10) on the eye relative to an interface between an iris (4) and a sclera (6), - a position of the probe relative to said eye, said position corresponding to an angle of rotation of the acquisition plane (16) of the ultrasonic probe (10) on the eye (1) around the pupil (2).

3. Method according to the preceding claim, wherein at least certain predetermined spatial configurations further correspond to an inclination of the acquisition plane (16) of the ultrasonic probe (10) with respect to the surface of the eye (1).

4. A method according to claims 1 to 3, wherein the orientation of the ultrasonic probe (10) is selected from: - a transverse orientation, in which the acquisition plane (16) of the ultrasonic probe (10) on the eye (1) extends over the surface of the eye (1) tangentially to the interface between the iris (4) and the sclera (6) of the eye (1), - a longitudinal orientation, in which the acquisition plane (16) of the ultrasound probe (10) on the eye extends radially across the surface of the sclera (6) relative to the interface between the iris (4) and the sclera (6) of the eye, - an axial orientation, in which the acquisition plane of the ultrasonic probe (10) on the eye extends to the surface of the iris (4) and the pupil (2) radially with respect to the interface between the iris (4) and the sclera (6) of the eye.

5. A method according to any one of the preceding claims, wherein each predetermined spatial configuration of the finite set of predetermined spatial configurations corresponds to a predetermined positioning of the ultrasonic probe (10), and the automated data processing unit selects the predetermined spatial configuration that has the predetermined positioning closest to the positioning of the probe defined by the positioning data.

6. A method according to any one of the preceding claims, further comprising a preliminary calibration step in which the ultrasonic probe is positioned relative to the eye at a predefined position and orientation, and a calibration command is sent by a user to the automated data processing unit, the positioning data of the ultrasonic probe then being determined from the movements of the ultrasonic probe relative to the predefined position and orientation.

7. A method according to any one of the preceding claims, wherein the automated data processing unit includes an information input interface and a user inputs part of the probe positioning data concerning an orientation of the ultrasonic probe relative to the eye.

8. A method according to any one of the preceding claims, wherein, in order to determine the display data, the automated data processing unit merges an image defined by the image data with the visual marker by superimposing said visual marker over a part of the image.

9. An ophthalmic ultrasound system configured to implement the method according to any one of claims 1 to 8, said system comprising: - an ultrasonic probe (10) configured to be positioned relative to an eye (1) and to emit and receive ultrasonic waves propagating in the eye (1) in order to generate image data defining at least one Image, - an inertial measurement unit attached to the ultrasonic probe (10) and incorporating at least one gyroscope and at least one accelerometer, said inertial measurement unit being adapted to measure at least one rotation around an axis and to measure at least one acceleration along an axis, the rotation measurement and the acceleration measurements forming positioning data for the ultrasonic probe, - an automated data processing unit comprising at least one processor and one memory, connected to the ultrasonic probe and the inertial measurement unit and configured to receive image data from the ultrasonic probe and positioning data from the inertial measurement unit for the ultrasonic probe for each image defined by the image data, - a screen configured to receive display data from the automated data processing unit and to display said data, the automated data processing unit being configured to, in response to the reception of image data and positioning data from the ultrasonic probe: - to select, for each image defined by the image data, from the positioning data of the ultrasonic probe for said image, a predetermined spatial configuration from a finite set of predetermined spatial configurations, the predetermined spatial configurations defining a position of the ultrasonic probe (10) and an orientation of the ultrasonic probe (10) with respect to a spatial reference frame corresponding to the configuration of an eye, - associate the image with a visual reference (20, 30) comprising visual indicators (24, 33) representative of the previously selected predetermined spatial configuration, the visual reference (20, 30) comprising a surface (21) bearing marks (22) distributed over said surface by rotational symmetry around a center (23) of said surface, and a visual indicator (24) representative of the position of the probe taking place at the location of a mark (22) whose location in the surface corresponds to the position of the ultrasonic probe (10) relative to the eye in the previously selected predetermined spatial configuration, - transmit to the screen display data including the image and the visual cue, so that the screen simultaneously displays the image and the visual cue.

10. Product computer program comprising program code instructions recorded on a non-volatile medium usable in a computer for the execution of processing steps of the process according to any one of claims 1 5 to 8, when said program is executed on a computer.

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