BIMODAL DIAGNOSTIC PROBE

Abstract

The invention relates to a bimodal diagnostic probe (1) used to examine biological tissues, said probe (1) comprising: - A body (12) having an elongated shape along a longitudinal axis (X), - The body having a distal part (11) intended to come as close as possible to the tissues to be examined, - At least one ultrasonic device (4) comprising an array of ultrasonic transducers (40), said array of ultrasonic transducers (40) being controlled to emit ultrasonic signals towards the tissues to be examined and to convert the reflected ultrasonic signals into electrical signals, - At least one optical device (3) comprising a light source, said at least one light source being controlled to emit a light beam (30) towards the tissues to be examined, the optical device also comprising at least one sensor for capturing the light signals scattered by the tissues.

Description

Technical field of the invention

[0001] The present invention relates to a bimodal diagnostic probe, intended to be integrated into a diagnostic system capable of generating images from ultrasound data and optical data. State of the art

[0002] Among endocrine pathologies, pituitary adenomas are low-grade, slow-growing tumors representing approximately 10% of primary brain tumors. They can cause the secretion of abnormally high amounts of one or more hormones (corticotropic adenoma secreting ACTH for Cushing's disease, somatotropic adenoma secreting growth hormone or GH for acromegaly, etc.). Cushing's disease (pituitary adenomas secreting ACTH) is certainly one of the most harmful for the patient.

[0003] Complete excision of the corticotroph adenoma allows the patient to recover. However, its detection is not always possible, despite advances in magnetic resonance imaging (MRI).

[0004] Magnetic resonance imaging is currently the examination of choice for locating the adenoma. However, imaging visualization of secreting adenomas (including those secreting ACTH (adrenocorticotropic hormone)) is difficult due to their small size.

[0005] Furthermore, surgical treatment remains the standard treatment to date, allowing for a cure when the excision is complete. Pituitary surgery is performed via a trans-sphenoidal "endonasal" approach under endoscopic guidance.

[0006] In the case of an adenoma visible on MRI, the neurosurgeon knows the location of the adenoma and will be able to reach the adenoma using an endoscope allowing visual control of the exploration of the gland and the resection of the adenoma. However, since MRI images and endoscopic visualization cannot be superimposed, exploration of the gland remains difficult.

[0007] In the case of an adenoma not visible on MRI, it is known to propose a total hypophysectomy, leading to post-operative pituitary insufficiency.

[0008] However, a parameter that differentiates adenomatous tissue from healthy pituitary tissue has recently been highlighted, this parameter being tissue stiffness (Meyer M et al., 2021). The pituitary gland and more specifically the anterior pituitary is in fact a tissue whose extracellular matrix is ​​rich in reticulin and collagen IV fibers.

[0009] The study of the micromechanical characterization of pituitary adenomas in comparison with healthy pituitary gland shows that the average stiffness (expressed in kilopascal or kPa), measured by atomic force microscopy (called AFM) in adenomatous tissues, differs significantly from that estimated in the healthy pituitary gland. Indeed, the average stiffness of adenomatous tissues is between 0.1 and 0.2 kPa for the adenomas (somatotrope and corticotrope) tested, while that measured in healthy pituitary parenchyma is approximately 10 kPa (Meyer M et al., 2021).

[0010] The intraoperative localization of the lesions could thus be evaluated by an approach based on the measurement of rigidity by means of a non-invasive probe (vis-à-vis the gland) using the ultrasound modality coupled with the optical modality.

[0011] A bimodal probe is known from document US2009 / 203991A1.

[0012] The aim of the invention is to have a bimodal probe capable of implementing both detection of the adenoma by ultrasound mode and enabling its resection using optical mode, said probe: allowing the superposition of ultrasound (elastographic) information on the optical image usually used by the neurosurgeon; having a spatial footprint adapted to the introduction of surgical instruments commonly used during this type of surgery;

[0013] In a non-limiting manner, the probe of the invention may in particular be used in the following fields of application: excision of pituitary adenomas, brain tumors in the broad sense (meningiomas, gliomas, cavernomas, craniopharyngiomas, etc.), tumors in the broad sense (liver, breast, lung, colon, bladder, prostate, thyroid, ovary). Statement of the invention

[0014] This aim is achieved by a bimodal diagnostic probe, used to examine biological tissues and intended to be integrated into a diagnostic system capable of generating images from ultrasound data and optical data, said probe comprising: A body having an elongated shape along a longitudinal axis, The body comprising a distal portion intended to come as close as possible to the tissues to be examined, At least one ultrasound device comprising a matrix of ultrasound transducers, said matrix of ultrasound transducers being controlled to emit ultrasound signals towards the tissues to be examined and to convert the reflected ultrasound signals into electrical signals, At least one optical device comprising a light source, said at least one light source being controlled to emit a light beam towards the tissues to be examined, the optical device also comprising at least one sensor responsible for capturing the light signals diffused by the tissues, The optical device being arranged to emit said light beam at the distal portion of the probe,The probe comprising a part mounted to slide in said body in a direction parallel to the longitudinal axis, said movable part comprising a distal end carrying the ultrasonic device, The probe comprising means for adjusting the longitudinal position of said movable part.

[0015] Thus, while the light beam is emitted via the distal part of the probe, the movable part which carries the ultrasound device at its end can move in sliding motion, thus allowing its longitudinal position to be adjusted. The light beam is thus emitted by the fixed part of the probe while the ultrasonic waves can be emitted from a position more or less distant from the tissues, depending on the position taken by the movable part.

[0016] According to a feature, the probe comprises a displacement sensor arranged to detect the longitudinal position of the moving part.

[0017] According to another feature, the probe includes a device for locking the moving part against sliding.

[0018] According to another feature, the probe comprises at least one mechanical pressure sensor located at the distal end of the movable part.

[0019] According to another feature, the ultrasonic device comprises a matrix of ultrasonic transducers.

[0020] According to another feature, the probe comprises a channel called an operating channel integrated into said body of the probe and extending in a direction parallel to the longitudinal axis.

[0021] The invention also relates to a diagnostic system capable of generating images from ultrasound data and optical data, said system comprising a bimodal probe and a control and processing unit to which said bimodal probe is connected, the bimodal probe being as defined above.

[0022] According to a particular feature, the system comprises means for acquiring the longitudinal position of the moving part of the probe and the control and processing unit is configured to determine the longitudinal position of said matrix of ultrasonic transducers relative to the optical device.

[0023] According to another feature, the control and processing unit is configured to correct the image obtained using the ultrasound device and / or the image obtained using the optical device by taking into account the longitudinal position of said matrix of ultrasound transducers relative to the optical device and in particular the distal front face through which the light beam is emitted.

[0024] According to another feature, the control and processing unit includes a module for superimposing the images obtained using the optical device and the images obtained using the ultrasound device.

[0025] According to another feature, the control and processing unit includes a module for superimposing images obtained using the ultrasound device and images obtained by MRI.

[0026] According to another feature, the system includes a module for processing images obtained using the ultrasound device, configured to distinguish the different rigidities of the tissues examined. Brief description of the figures

[0027] Other characteristics and advantages will appear in the detailed description which follows, given with reference to the attached drawings in which: There figure 1 shows an exemplary embodiment of the bimodal probe of the invention; The Figures 2A to 2D show several variant embodiments of the distal part of the bimodal probe of the invention; The figure 3 schematically shows the hardware and software architecture of the diagnostic system of the invention integrating said bimodal probe; Detailed description of at least one embodiment

[0028] In reference to the figure 1 , according to the invention, the bimodal probe 1 comprises a body 12 of elongated shape along a longitudinal axis (X). The probe 1 comprises a first part called proximal 10 and a second part called distal 11 opposite.

[0029] The proximal part 10 of the probe comprises means 100 for gripping and manipulating the probe 1 by an operator (for example the surgeon).

[0030] The probe 1 of the invention can in particular be mounted on an articulated arm 2, which optionally can be controlled by the control and processing unit (see below).

[0031] The distal part 11 of the probe 1 comprises detection means, intended to be brought close to the tissues to be examined.

[0032] The detection means of the bimodal probe comprise an optical device 3 and an ultrasonic device 4.

[0033] The distal part 11 of the probe advantageously comprises a so-called front face 110 oriented perpendicular to its longitudinal axis (X). This front face 110 is intended to come opposite the tissues to be examined.

[0034] The optical device 3 comprises at least one light source. The light source may comprise one or more light-emitting diodes in a distal position of the probe or at a distance in coupling with at least one optical fiber to convey the light through the body 12 of the probe (as in the figure 1 ).

[0035] The light beam 30 is delivered at the distal part 11 of the probe, through the front face 110 of the probe 1 and oriented so as to be emitted in the direction of the tissues to be examined.

[0036] The optical device 3 also comprises at least one optical camera responsible for capturing the light waves reflected by the tissues, after illumination. The optical camera can be located in the distal or proximal part of the body 12. In the case of the proximal configuration (as in the figure 1 ), the routing of light from the area to be examined to the optical camera can be carried out by a network of optical fibers or any other optical device. The optical camera, composed of several photodiodes, is configured to convert the captured light waves into electrical signals that can be used by a processing module (see below).

[0037] THE Figures 2A to 2D show several examples of implementation and positioning of the components of the optical device and the ultrasound device. The observation of the area to be examined is for example carried out through an optical receiver 31, which can integrate one or more lenses.

[0038] The ultrasonic device 4 comprises several ultrasonic transducers 40, advantageously a matrix of ultrasonic transducers. These ultrasonic transducers 40 may be piezoelectric bodies or capacitive micromachined ultrasonic transducers (called CMUTs). The material of the piezoelectric body may be quartz, ceramic (lead zirconate titanate or polyvinylidene fluoride) or polymer. The matrix of ultrasonic transducers 40 may take different shapes, this shape being able to be adapted to that of the cross-section of the body of the bimodal probe.

[0039] For example, the transducer array may have a semi-circular shape ( Figure 2A ), rectangular ( Figure 2B ), annular ( Figure 2C ) or circular ( 2D figure ).

[0040] The ultrasound device 4 is controlled to insonify a region of interest with ultrasonic waves: in an elastographic mode, a plane shear wave is induced in the region of interest by the insonification, and the propagation of the shear “plane” is measured in real time at high speed by imaging. The ultrasound part of the probe 1 thus operates in transmission-reception.

[0041] According to the invention, the bimodal probe 1 comprises a part 13 mounted to slide relative to the body 12 of the probe along the longitudinal axis (X) of the probe.

[0042] This mobile part 13 has a distal end, located on the side of the distal part 11 of the probe. At this distal end, the mobile part 13 carries the ultrasonic device 4. It is thus possible to adjust the position of the ultrasonic device 4 relative to the rest of the body 12 of the probe.

[0043] On the proximal side, the movable part 13 may comprise a gripping handle 132, which can be used by the operator to slide the movable part 13 along its axis.

[0044] This mobile part 13 makes it possible to move the ultrasound device 4 and to bring the matrix of ultrasound transducers 40 as close as possible to the tissues to be examined to enable ultrasound imaging, while the light beam 30 of the optical device can be emitted from a more distant position in order to maintain an observation field suitable for surgery. It is thus possible to adjust the position of each of the two devices, using only one probe 1.

[0045] According to the invention, the probe 1 may comprise means for adjusting (not shown) the longitudinal position of the movable part relative to the body of the probe. These adjustment means may be formed of several notches or any other equivalent solution. A locking member 131 in position may be integrated into the probe. On the figure 1 , we can see that the moving part is moved longitudinally by a distance D_x.

[0046] A displacement sensor 130 can also be integrated into the probe 1 to detect the position of the moving part 13 relative to the rest of the body 12 of the probe.

[0047] The sliding of the mobile part 13 of the probe 1 may be done manually or by motor. The probe 1 may thus integrate an electric motor, controlled to allow translational movement of the mobile part 13. The transfer of movement from the electric motor to the mobile part 13 may be implemented using a rack and / or worm mechanism or any other equivalent solution.

[0048] Advantageously, the probe 1 may comprise a channel, called operator channel 5 ( Figures 2A to 2D ), which extends through its body 12, in the longitudinal direction (X). This channel 5 can in particular be used by the operator either to inject substances used for cleaning or for any other operation, or to suck up liquid or solid waste and thus allows the operator to reach the tissues to be examined from outside the probe 1.

[0049] The mobile part 13 may be provided with at least one pressure sensor (not shown) making it possible to measure the force applied to the tissues at the time of the elastographic measurement. The pressure sensor aims to avoid causing damage to the tissues by contact with the probe 1, to obtain minimal deformation of the tissues and advantageously to always be able to apply a force of the same intensity during each ultrasound measurement.

[0050] The probe may have an electric battery housed in its body 12, to power its various components (optical device, ultrasonic device) and / or be connected to an external power source.

[0051] In reference to the figure 3 , to operate, the bimodal probe 1 is integrated into a more global diagnostic system.

[0052] Without limitation, in addition to the bimodal probe 1, the diagnostic system may comprise at least one control and processing unit UC and a human-machine interface HMI.

[0053] The human-machine interface HMI makes it possible in particular to enter physiological data relating to the patient being monitored, to configure the operation of the probe 1 (for example by adjusting the position of the mobile part 13 carrying the ultrasound device 4) and the type of processing applied to the ultrasound data (mode B, elastography, Doppler).

[0054] The probe 1 is for example removably connected to said control and processing unit UC.

[0055] The control and processing unit UC includes: A data transmission / reception module M1 to which the optical device of the probe is connected; this module M1 is responsible for controlling the light source (for example one or more light-emitting diodes) to emit the light beam 30 towards the tissues to be examined and for receiving the data representative of the light fluxes received by the optical camera integrated into the optical device 3 to convert them into electrical data; each light-emitting diode can for example be controlled individually; A module M2 for processing the data representative of the light flux captured by the optical device; A data transmission / reception module M3 to which the ultrasound device of the probe is connected;this module is responsible for controlling several ultrasound transducers 40 to emit ultrasound towards the tissues to be examined and to receive the data representative of the ultrasound waves received by the ultrasound transducers 40; At least one module M4 for processing the data representative of the ultrasound waves captured by the ultrasound transducers, this processing module M4 being able to be configured to carry out a conventional B mode processing, an elastography processing and / or Doppler type processing (optional); A module M5 for measuring the position of the mobile part 13 carrying the ultrasound device relative to the body 12; responsible for sending or not sending position data to the module M6. A module M6 for controlling the position of the mobile part 13, responsible for moving the latter. A module M7 for controlling the articulated arm 2. A module M8 for superimposing the images obtained via the optical mode and via the ultrasound mode;This module may in particular rely on the different possible ultrasound processing modes mentioned above (B mode, elastography, Doppler); Optionally, an M9 module for acquiring images obtained by MRI and an M10 module for processing these images; Optionally, an M11 module for superimposing images obtained by MRI and those obtained by an ultrasound processing mode;

[0056] B mode corresponds to the classic visualization mode used during an ultrasound.

[0057] The M4 module for processing data representative of ultrasound waves makes it possible to generate a tissue stiffness map. These images are, for example, three-dimensional ultrasounds of the region of interest.

[0058] This mapping can reflect raw measurements or relative measurements, by zones. The HMI can, for example, be configured to set one or more tissue stiffness thresholds and configure the resulting images taking into account each set threshold. For example, it is possible to display the observed areas with different colors, taking into account their stiffness level in relation to each of the pre-recorded thresholds. This will make it easier to discriminate pathological areas from healthy areas.

[0059] It should be noted that the M8 image superposition module will be able to adapt the images generated by the ultrasound device taking into account its position determined by the displacement sensor.

[0060] Each image superposition module M8, M11 makes it possible to superimpose images obtained using the optical device 3 and the ultrasound device 4 integrated into the same probe 1. In other words, the probe of the invention makes it possible to collect images in real time and simultaneously via these two imaging channels. It will also be possible to superimpose images recovered via MRI.

[0061] In a non-limiting manner, probe 1 can thus be used to locate the lesion and then to confirm the diagnosis by: Superposition of the elastographic image and the B-mode image (B-mode = ultrasound visualization mode); Superposition of the image obtained via optical data and the elastographic image; Superposition of the image obtained by MRI and the elastographic image; Spatialization and calculation of the volume of the lesion: combination of the different modalities and correlation study (common and specific areas for each mode).

[0062] The said probe can also help in the following situations: To guide the excision by projection of the lesion onto the 2D image obtained using optical data; To monitor the resection of the lesion using spatialization and calculation of the volume of the lesion; To final control of the resection;

[0063] The medical applications targeted by the present invention are pituitary adenomas, brain tumors in the broad sense (meningiomas, gliomas, cavernomas, craniopharyngiomas, etc.), tumors in the broad sense (liver, breast, lung, etc.) and in particular recurrences of the tumors mentioned above. In the example of pituitary tumors and more particularly of ACTH pituitary microadenoma, the diagnostic system makes it possible, in a first step, to detect the lesion by measuring the rigidity of the scanned tissues, in a second step to guide the excision in real time by locating, thanks to the Doppler function of the device, the important vascular structures, and finally to allow a complete excision of the adenoma by precisely delimiting the contours of the lesion with the aim of removing it entirely without removing healthy tissue and thus avoiding surgical exploration which is harmful to the gland.

[0064] The invention has many advantages, including: We obtain a probe with a compact architecture while having optical and ultrasound bimodality; We obtain a probe with a solution allowing it to come into contact with the tissues to be examined to carry out ultrasound imaging and then return to its initial position to leave the field of vision of the optical modality free.

Claims

1. Bimodal diagnostic probe (1), used to examine biological tissues and intended to be integrated into a diagnostic system capable of generating images from ultrasound data and optical data, said probe (1) comprising: - A body (12) having an elongated shape along a longitudinal axis (X), - The body (12) comprising a distal portion (11) intended to come as close as possible to the tissues to be examined, - At least one ultrasound device (4) comprising a matrix of ultrasound transducers (40), said matrix of ultrasound transducers (40) being controlled to emit ultrasound signals towards the tissues to be examined and to convert the reflected ultrasound signals into electrical signals, - At least one optical device (3) comprising a light source, said at least one light source being controlled to emit a light beam (30) towards the tissues to be examined,the optical device also comprising at least one sensor responsible for capturing the light signals diffused by the tissues, - , Characterized in that : - The optical device (3) is arranged to emit said light beam (30) at the distal part (11) of the probe, - The probe (1) comprises a part (13) mounted to slide in said body (12) in a direction parallel to the longitudinal axis (X), said movable part (13) comprising a distal end carrying the ultrasonic device (4), - The probe (1) comprises means for adjusting the longitudinal position of said movable part (13).

2. Probe according to claim 1, characterized in that it comprises a position sensor arranged to detect the longitudinal position of the moving part (13).

3. Probe according to claim 1 or 2, characterized in that it comprises a locking device (131) for the sliding of the movable part (13).

4. Probe according to one of claims 1 to 3, characterized in that it comprises at least one mechanical pressure sensor located at the distal end of the movable part (13).

5. Probe according to one of claims 1 to 4, characterized in that the ultrasonic device (4) comprises an array of ultrasonic transducers (40).

6. Probe according to one of claims 1 to 5, characterized in that it comprises a channel called the operating channel (5) integrated into said body (12) of the probe and extending in a direction parallel to the longitudinal axis (X).

7. Diagnostic system capable of generating images from ultrasound data and optical data, said system comprising a bimodal probe (1) and a control and processing unit (UC) to which said bimodal probe is connected, said system being characterized in that the bimodal probe is as defined in one of claims 1 to 6.

8. System according to claim 7, characterized in thatit comprises means for acquiring the longitudinal position of the mobile part (13) of the probe and in that the control and processing unit (UC) is configured to determine the longitudinal position of said matrix of ultrasonic transducers (40) relative to the optical device (3).

9. System according to claim 8, characterized in that the control and processing unit (UC) is configured to correct the image obtained using the ultrasound device (4) and / or the image obtained using the optical device (3) taking into account the longitudinal position of said matrix of ultrasound transducers (40) relative to the optical device (3).

10. System according to one of claims 7 to 9, characterized in that the control and processing unit (UC) comprises a module (M8) for superimposing the images obtained using the optical device (3) and the images obtained using the ultrasound device (4).

11. System according to one of claims 7 to 10, characterized in that the control and processing unit (UC) comprises a module (M11) for superimposing the images obtained using the ultrasound device (4) and the images obtained by MRI.

12. System according to one of claims 7 to 11, characterized in that It includes a module (M4) for processing images obtained using the ultrasound device, configured to distinguish the different rigidities of the tissues examined.