BIMODAL DIAGNOSTIC PROBE

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 ultrasonic and optical data. State of the art

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

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

[0004] Magnetic resonance imaging is currently the preferred examination for locating adenomas. However, visualizing secreting adenomas (including those secreting ACTH (adrenocorticotropic hormone)) using imaging is challenging due to their small size.

[0005] Furthermore, surgical treatment remains the gold standard to date, as it leads to a cure when the excision is complete. Pituitary surgery is performed via a transsphenoidal endonasal approach under endoscopic guidance.

[0006] If an adenoma is visible on MRI, the neurosurgeon knows its location and can access it using an endoscope, allowing visual control of the gland's exploration and adenoma resection. However, because MRI and endoscopic images cannot be superimposed, exploring the gland remains challenging.

[0007] In cases of adenoma not visible on MRI, it is known to offer a total hypophysectomy, leading to postoperative pituitary insufficiency.

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

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

[0010] The intraoperative localization of the lesions could thus be assessed by an approach based on the measurement of stiffness using a non-invasive probe (in relation to the gland) using the ultrasound modality coupled with the optical modality.

[0011] A bimodal probe is known from document US2009 / 203991 A1 and also from US2006 / 036182A1.

[0012] The aim of the invention is to provide a bimodal probe capable of simultaneously detecting the adenoma by ultrasound mode and enabling its resection via optical mode, said probe: allowing the superimposition of ultrasonic (elastographic) information onto 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] Without limitation, 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). Description of the invention

[0014] This goal 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 and optical data, said probe comprising: A body having an elongated shape along a longitudinal axis, the body comprising a distal part intended to come as close as possible to the tissues to be examined, at least one ultrasound device comprising an array of ultrasound transducers, said array 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 for capturing the light signals scattered by the tissues, the optical device being arranged to emit said light beam at the distal part of the probe,The probe comprising a movable part mounted to slide within 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 carrying the ultrasound device at its tip can slide, allowing its longitudinal position to be adjusted. The light beam is therefore emitted by the fixed part of the probe, while the ultrasound waves can be emitted from a position closer to or further from the tissues, depending on the position of the movable part.

[0016] One particular feature of the probe is that it includes a displacement sensor arranged to detect the longitudinal position of the moving part.

[0017] Another distinctive feature of the probe is that it includes a sliding locking device for the moving part.

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

[0019] Another distinctive feature is that the ultrasonic device includes an array of ultrasonic transducers.

[0020] According to another feature, the probe includes a channel called the operator channel integrated into the probe body and extending in a direction parallel to the longitudinal axis.

[0021] The invention is described in the attached list of claims. Brief description of the figures

[0022] Other features and advantages will appear in the detailed description that follows, in conjunction with the attached drawings, in which: There figure 1shows an example of an embodiment of the bimodal probe of the invention; The figures 2A to 2D show several 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 incorporating said bimodal probe; Detailed description of at least one embodiment

[0023] With reference to the figure 1 According to the invention, the bimodal probe 1 comprises a body 12 elongated along a longitudinal axis (X). The probe 1 comprises a first part called proximal 10 and a second part called distal 11 opposite.

[0024] The proximal part 10 of the probe includes means 100 for grasping and manipulating the probe 1 by an operator (for example the surgeon).

[0025] 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).

[0026] The distal part 11 of probe 1 includes detection means, intended to be brought close to the tissues to be examined.

[0027] The detection means of the bimodal probe include an optical device 3 and an ultrasonic device 4.

[0028] The distal part 11 of the probe advantageously includes a front face 110 oriented perpendicularly to its longitudinal axis (X). This front face 110 is intended to be positioned opposite the tissues to be examined.

[0029] The optical device 3 includes at least one light source. The light source may include one or more light-emitting diodes located distal to the probe or at a distance coupled with at least one optical fiber to carry the light through the probe body 12 (as on the figure 1 ).

[0030] 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 towards the tissues to be examined.

[0031] The optical device 3 also includes at least one optical camera designed to capture 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 on the figure 1The transmission of light from the area to be examined to the optical camera can be achieved via a fiber optic network or any other optical device. The optical camera, composed of several photodiodes, is configured to convert the captured light waves into electrical signals usable by a processing module (see below).

[0032] THE figures 2A to 2D They show several examples of the implementation and positioning of the components of the optical and ultrasonic devices. The observation of the area to be examined is, for example, carried out through an optical receiver 31, which may incorporate one or more lenses.

[0033] The ultrasonic device 4 comprises several ultrasonic transducers 40, advantageously an array of ultrasonic transducers. These ultrasonic transducers 40 can be piezoelectric elements or capacitive micromachined ultrasonic transducers (CMUTs). The material of the piezoelectric element can be quartz, ceramic (lead zirconate titanate or polyvinylidene fluoride), or polymer. The array of ultrasonic transducers 40 can take various forms, which can be adapted to the cross-sectional area of ​​the bimodal probe body.

[0034] As an example, the transducer array may have a semi-circular shape ( figure 2A ), rectangular ( figure 2B ), ring finger ( figure 2C ) or circular ( figure 2D ).

[0035] The ultrasonic 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 insonification, and the propagation of the shear plane is measured in real time at high speed by imaging. The ultrasonic part of probe 1 thus operates in transmit-receive mode.

[0036] According to the invention, the bimodal probe 1 comprises a part 13 mounted movable in sliding relative to the body 12 of the probe along the longitudinal axis (X) of the probe.

[0037] This movable part 13 has a distal end, located on the side of the distal part 11 of the probe. At this distal end, the movable 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.

[0038] On the proximal side, the movable part 13 may include a gripping handle 132, which can be used by the operator to slide the movable part 13 along its axis.

[0039] This movable part 13 allows the ultrasound device 4 to be moved and the ultrasound transducer array 40 to be brought as close as possible to the tissues to be examined for ultrasound imaging, while the light beam 30 of the optical device can be emitted from a more distant position to maintain a field of view suitable for surgery. It is therefore possible to adjust the position of each of the two devices using only a single probe 1.

[0040] According to the invention, the probe 1 may include means for adjusting (not shown) the longitudinal position of the movable part relative to the probe body. These adjustment means may consist of several notches or any other equivalent solution. A locking element 131 in position may be integrated into the probe. On the figure 1 , we can see that the moving part is displaced longitudinally by a distance D_x.

[0041] 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 probe body 12.

[0042] The sliding of the movable part 13 of the probe 1 can be done manually or by motor. The probe 1 can therefore incorporate an electric motor, controlled to allow translational movement of the movable part 13. The transfer of motion from the electric motor to the movable part 13 can be implemented using a rack and pinion and / or worm gear mechanism or any other equivalent solution.

[0043] Advantageously, probe 1 may include a channel, called operator channel 5 ( figures 2A to 2D ), which extends through its body 12, along the longitudinal direction (X). This channel 5 can be used by the operator either to inject substances used for cleaning or for any other operation, or to aspirate liquid or solid waste, thus allowing the operator to reach the tissues to be examined from outside the probe 1.

[0044] The moving part 13 can be equipped with at least one pressure sensor (not shown) for measuring the force applied to the tissues during the elastographic measurement. The purpose of the pressure sensor is to avoid causing tissue damage through contact with the probe 1, to achieve minimal tissue deformation, and advantageously, to ensure that a consistent force intensity is applied during each ultrasound measurement.

[0045] 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.

[0046] With reference to the figure 3 To function, the bimodal probe 1 is integrated into a more comprehensive diagnostic system.

[0047] Without limitation, in addition to the bimodal probe 1, the diagnostic system may include at least one control and processing unit (CPU) and one human-machine interface (HMI).

[0048] The human-machine interface (HMI) allows, in particular, the entry of physiological data relating to the patient being monitored, the configuration of 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 (B-mode, elastography, Doppler).

[0049] Probe 1, for example, is removably connected to said control and processing unit UC.

[0050] The control and processing unit (CPU) comprises: A data transmission / reception module M1 to which the probe's optical device 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 data representing the light fluxes received by the optical camera integrated into the optical device 3 in order to convert them into electrical data; each light-emitting diode can, for example, be controlled individually; A data processing module M2 for the data representing the light flux captured by the optical device; A data transmission / reception module M3 to which the probe's ultrasonic device is connected;This module is responsible for controlling several ultrasonic transducers 40 to emit ultrasound waves towards the tissues to be examined and for receiving representative data of the ultrasonic waves received by the ultrasonic transducers 40; At least one module M4 for processing the representative data of the ultrasonic waves captured by the ultrasonic transducers, this processing module M4 being configurable to perform conventional B-mode processing, elastography processing, and / or Doppler processing (optional); A module M5 for measuring the position of the moving part 13 carrying the ultrasonic device relative to the body 12; responsible for sending or not sending position data to module M6. A module M6 for controlling the position of the moving part 13, responsible for moving it. A module M7 for controlling the articulated arm 2. A module M8 for superimposing the images obtained via optical mode and via ultrasonic mode;This module will notably be able to utilize the various 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;

[0051] Mode B corresponds to the classic visualization mode used during an ultrasound.

[0052] The M4 module for processing representative ultrasound wave data allows for the generation of tissue stiffness maps. These images are, for example, three-dimensional ultrasound scans of the region of interest.

[0053] This mapping can reflect raw measurements or relative measurements, by area. The human-machine interface (HMI) can, for example, be configured to set one or more tissue stiffness thresholds and configure the resulting images accordingly. For instance, it is possible to display observed areas in different colors based on their stiffness level relative to each pre-defined threshold. This makes it easier to distinguish pathological areas from healthy areas.

[0054] It should be noted that the M8 image overlay module will be able to adapt the images generated by the ultrasonic device by taking into account its position determined by the displacement sensor.

[0055] Each image-overlay module M8, M11 allows for the superimposition of images obtained using the optical device 3 and the ultrasonic device 4 integrated into the same probe 1. In other words, the probe of the invention allows for the real-time and simultaneous acquisition of images via these two imaging channels. It will also be possible to superimpose images acquired via MRI.

[0056] By way of example, probe 1 can 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 lesion volume: combination of the different modalities and correlation study (common and mode-specific areas).

[0057] This probe can also be helpful in the following situations: Guiding the excision by projecting the lesion onto the 2D image obtained using optical data; Monitoring the resection of the lesion through spatialization and calculation of the lesion volume; Final control of the resection;

[0058] The medical applications targeted by the present invention are pituitary adenomas, brain tumors in the broadest sense (meningiomas, gliomas, cavernomas, craniopharyngiomas, etc.), tumors in the broadest sense (liver, breast, lung, etc.), and in particular, recurrences of the aforementioned tumors. In the case of pituitary tumors, and more specifically ACTH-secreting pituitary microadenomas, the diagnostic system first detects the lesion by measuring the stiffness of the scanned tissues; second, it guides the excision in real time by locating important vascular structures using the device's Doppler function; and finally, it enables complete excision of the adenoma by precisely delineating the lesion's contours in order to remove it entirely without removing healthy tissue, thus avoiding surgical exploration that could be harmful to the gland.

[0059] The invention offers numerous advantages, including: We obtain a probe with a compact architecture while having both optical and ultrasonic bimodality; We obtain a probe with a solution allowing it to come into contact with the tissues to be examined to perform ultrasonic imaging and then return to its initial position to leave the field of vision of the optical modality free.

Claims

1. Diagnostic system capable of generating images from ultrasonic data and optical data, said system comprising a bimodal diagnostic probe (1) and a control and processing unit (UC) to which said bimodal diagnostic probe is connected being used to examine biological tissues and comprising: - a body (12) having an elongate shape along a longitudinal axis (X), - the body (12) comprising a distal part (11) intended to come as close as possible to the tissues to be examined, - at least one ultrasonic device (4) comprising a matrix array of ultrasonic transducers (40), said matrix 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 responsible for capturing the light signals scattered by the tissues, - the optical device (3) being arranged to emit said light beam (30) at the distal part (11) of the probe, - the probe (1) comprising a part (13) slidably mounted in said body (12) in a direction parallel to the longitudinal axis (X), said movable part (13) comprising a distal end bearing the ultrasonic device (4), - the probe (1) comprising means for adjusting the longitudinal position of said movable part (13), - characterized in that: - the system comprises means for acquiring the longitudinal position of the movable part (13) of the probe, and in that the control and processing unit (UC) is configured to determine the longitudinal position of said matrix array of ultrasonic transducers (40) with respect to the optical device (3), - the control and processing unit (UC) is configured to correct the image obtained with the aid of the ultrasonic device (4) and / or the image obtained with the aid of the optical device (3) taking account of the longitudinal position of said matrix array of ultrasonic transducers (40) with respect to the optical device (3).

2. System according to Claim 1, characterized in that the probe comprises a position sensor arranged to detect the longitudinal position of the movable part (13).

3. System according to Claim 1 or 2, characterized in that the probe comprises a device (131) for slidingly blocking the movable part (13).

4. System according to any of Claims 1 to 3, characterized in that the probe comprises at least one mechanical pressure sensor located at the distal end of the movable part (13).

5. System according to any of Claims 1 to 4, characterized in that the ultrasonic device (4) comprises a matrix array of ultrasonic transducers (40).

6. System according to any of Claims 1 to 5, characterized in that the probe comprises a channel, referred to as operating channel (5), integrated into said body (12) of the probe and extending in a direction parallel to the longitudinal axis (X).

7. System according to any of Claims 1 to 6, characterized in that the control and processing unit (UC) comprises a module (M8) for superposing images obtained by means of the optical device (3) and images obtained by means of the ultrasonic device (4).

8. System according to any of Claims 1 to 7, characterized in that the control and processing unit (UC) comprises a module (M11) for superposing images obtained by means of the optical device (4) and images obtained by MRI.

9. System according to any of Claims 1 to 8, characterized in that it comprises a module (M4) for processing images obtained by means of the ultrasonic device, configured to distinguish the different rigidities of tissues examined.