Implantable medical device for brain tissue imaging and / or therapy

Abstract

The invention relates to an implantable device (1) comprising: - an ultrasound cell (11) comprising electrical connection terminals, - a support plate (12) comprising through openings through which the connection terminals pass, and - an attachment piece (13) which can cooperate with the connection terminals, the attachment piece (13) comprising a collar which, when the ultrasound cell (11), the support plate (12) and the attachment piece (13) are connected, presses the support plate (12) against the ultrasound cell (11).

Description

TECHNICAL FIELD

[0001] The present invention relates to the general technical field of ultrasound devices for treating the brain tissue of a human or an animal by ultrasound in order to help a practitioner in the treatment of a pathology. BACKGROUND

[0002] Various techniques for treating brain tissue are known.

[0003] In particular, the known technique developed by the Applicant consists in using a treatment device comprising:

[0004] - an implantable intracranial device,

[0005] - a control unit, remote from the intracranial device, and

[0006] - connection means between the intracranial device and the control unit.

[0007] The intracranial device is intended to be positioned in a drill hole made in the skull of a patient. The intracranial device comprises:

[0008] - a support;

[0009] - one (or more) transducer(s) for generating ultrasound treatment waves and mounted to the support,

[0010] - one (or more) electrical connection terminal(s) intended to cooperate with the connection means.

[0011] The control unit 2 is able to supply electrical energy to the intracranial device and to adjust the operating parameters of the intracranial device.

[0012] The connection means are adapted to electrically connect the intracranial device to the control unit. The connection means generally comprise:

[0013] - one (or more) electrical connection cable(s) connected at one end to the control unit, and

[0014] - one (or more) transcutaneous spike needle(s) connected at the other end to the cable.

[0015] The intracranial device works as follows. Once implanted in the skull of a patient, it is subjected to a series of treatment sessions in order to treat a pathology affecting the patient.

[0016] At each new treatment session, the intracranial device is connected to the control unit via the connection means: the practitioner connects the cable to the control unit and then inserts the spike needle through the skin of the patient to the terminal of the ultrasound device.

[0017] Once the end of the spike needle is connected to the terminal, the control unit can be activated in order to supply electrical energy to the ultrasound device.

[0018] The above technique makes it possible to effectively treat brain disorders.

[0019] One aim of the application is to propose an improved intracranial device which makes it possible to increase the safety of the patient during the connection phase of the intracranial device with the control unit, in particular during the insertion of the spike through the skin of the skull of the patient.

[0020] Another aim of the application is to propose an improved intracranial device which makes it possible to reduce the risk of deterioration during the connection phase of the intracranial device with the control unit, in particular during the insertion of the spike through the skin of the skull of the patient. SUMMARY

[0021] To this end, the application proposes an implantable device intended to be positioned in a hole provided in the skull of a patient, the implantable device comprising:

[0022] - a support plate comprising a first surface and a second surface opposite the first surface,

[0023] - an ultrasound cell intended to be mounted to the support plate, the ultrasound cell comprising:

[0024] • a housing comprising a bottom, at least one side wall and an upper surface opposite the bottom, the housing being intended to be positioned on the first surface of the support plate,

[0025] • a plurality of transducers provided in the housing for generating ultrasound waves for treating brain disorders,

[0026] • an electrical connection terminal attached to the housing for connecting the ultrasound cell to a remote control unit via an electrical connection device,

[0027] characterized in that:

[0028] - the electrical connection terminal comprises a pin which projects outwardly from the housing in a direction perpendicular to the bottom and which is oriented from the bottom toward the upper surface of the housing,

[0029] - the support plate comprises a through opening through which the pin passes,

[0030] - the implantable device further comprises an attachment comprising:

[0031] • a conduit adapted to accommodate at least a portion of the pin, and

[0032] • a surrounding collar which extends perpendicularly to the longitudinal axis of the conduit,

[0033] when the ultrasound cell, the support plate and the attachment are connected, the collar is intended to contact the second surface of the support plate so as to press the support plate against the housing.

[0034] The fact that the ultrasonic unit, support plate, and attachment consist of three separate components can facilitate the manufacture of implantable devices, each of which can be manufactured individually.

[0035] The following facts:

[0036] - The ultrasonic unit includes outwardly protruding connection terminals.

[0037] - The support plate includes a through opening through which the connecting terminals pass.

[0038] - Once the connecting terminal is inserted into the through opening, the attachment will cooperate with the connecting terminal to press the support plate against the ultrasonic unit.

[0039] It can facilitate the assembly of various components that make up an implantable device, and thus benefit its manufacturing method.

[0040] The fact that the attachment includes a collar:

[0041] On the one hand, it can protect the electronic board contained in the housing of the ultrasound unit, especially when a physician inserts a transdermal needle near a blind hole designed to accommodate the needle.

[0042] - On the other hand, the deformation of the support plate can be limited by distributing the force applied by the transdermal needle (when it is inserted into the connecting terminal) over a larger surface of the support plate.

[0043] Preferred, but not limiting, aspects of the present invention are as follows:

[0044] - Width L of the collar Coll With the width L of the catheter Cond The ratio between them can be between 1 / 4 and 2, preferably between 1 / 2 and 3 / 2, or even more preferably equal to 1;

[0045] The width L of the collar Coll Width L of the upper surface of the housing Log The ratio between them can be between 1 / 2 and 2, preferably between 2 / 3 and 1.

[0046] - The shape of the collar can be circular;

[0047] - The collar may include at least two radially opposed through lumens;

[0048] The pin may be cylindrical and include threads on its sidewalls. The conduit is formed by a nut, the threaded hole of which is designed to cooperate by threaded engagement with the threads on the sidewalls of the pin.

[0049] - the pin can comprise an upper wall opposite the bottom of the housing and a blind hole intended to accommodate one end of the connection device, the upper wall comprising a counterbore made at the entrance of the blind hole;

[0050] - the pin can comprise a stopper at its base, the edges of the through opening of the support plate being intended to press on the stopper when the pin is inserted in said through opening;

[0051] - the edges of the through opening of the support plate can be covered with a layer of polymeric material, for example silicone;

[0052] - the distance between the center of the through opening and the center of gravity of the plate can be non-zero.

[0053] The application also relates to a system for imaging and / or treating brain tissue, said system comprising a control unit and an electrical connection device, characterized in that it further comprises an implantable device as described above. BRIEF DESCRIPTION OF DRAWINGS

[0054] Other advantages and characteristics of the application will better emerge from the following description of several variant embodiments given by way of non-limiting example, with the aid of the appended drawings in which:

[0055] - Figure 1 is a schematic perspective view of an implantable medical device,

[0056] - Figure 2 is a schematic perspective view of an ultrasound unit of an implantable medical device,

[0057] - Figure 3 is a schematic perspective view of a support plate of an implantable medical device,

[0058] - Figure 4 is a schematic perspective view of an attachment of an implantable medical device. DETAILED DESCRIPTION

[0059] Examples of implantable medical devices will now be described with reference to the appended drawings. In these different figures, identical elements are denoted by the same reference signs.

[0060] 1. SUMMARY

[0061] With reference to Figure 1 , the implantable medical device 1 comprises:

[0062] - an ultrasound unit 11 for emitting imaging or therapeutic ultrasound waves,

[0063] - a support plate 12 on which said ultrasound unit 11 is mounted, and

[0064] - an attachment piece 13 which stops the ultrasound unit 11 against the support plate 12.

[0065] As Figures 2 to 4 illustrated, the ultrasound unit 11, the support plate 12 and the attachment piece 13 are separate elements which are intended to be connected to form the implantable medical device 1. More particularly, to form the implantable medical device 1, these different elements are connected so that the support plate 12 extends between the ultrasound unit 11 and the attachment piece 13.

[0066] The medical device 1 can be implanted in the skull of a patient to enable treatment and / or imaging of a brain region of interest.

[0067] To this end, the practitioner performs a craniectomy. An incision is made on the scalp and then the skin (and the muscle, if present) is raised (all raised) to reveal the skull. The skull is then cut to form a bone flap. The bone flap of the skull is removed to make way for a skull hole in which the intracranial device can be positioned.

[0068] The positioning of the device 1 consists in inserting the device 1 into the cranial hole so that the ultrasound unit 11 extends facing the brain region of interest. Once the device 1 has been correctly positioned, the border 124 of the support plate 12 is attached to the periphery of the cranial hole by any means known to those skilled in the art (anchoring screws, gluing, etc.) and then the scalp and the muscle are put back in place to cover the device 1. Thus, once implanted, the ultrasound unit 11 faces the brain region of interest while the attachment piece 13 extends facing the scalp of the patient.

[0069] At each new treatment session, the practitioner electrically connects the medical device 1 to a remote control unit using connection means. These connection means in particular comprise:

[0070] - an electrically conductive cable,

[0071] - a spike mounted at one end of the cable, said spike being able to be inserted into the connection terminal of the ultrasound unit, and

[0072] - a connection socket at the other end of the cable, said connection socket being able to be connected to a complementary socket of the control unit.

[0073] More particularly, the practitioner connects the connection socket to the remote control unit. Then, the practitioner inserts the spike into the scalp of the patient and guides the end of the spike into the blind hole of the connection terminal, thereby completing the electrical connection of the ultrasound device 1 to the remote control unit.

[0074] The different elements constituting the implantable medical device (ultrasound unit, support plate, attachment piece) will now be described in more detail.

[0075] 2. Ultrasonic cell

[0076] Reference is made to Figure 2 , the ultrasonic unit 11 comprises:

[0077] - a housing 111,

[0078] - electrical connection terminals 114 for connecting the ultrasonic unit 11 to a remote control unit.

[0079] 2.1. Housing

[0080] The housing 111 comprises a bottom 1111 and one or several side walls 1112. In Figure 2 In the embodiment illustrated, the upper surface of the housing 111 opposite the bottom 1111 is open. In other words, the upper surface of the housing is devoid of an upper wall. This facilitates the dissipation of the heat generated by the electronic boards towards the outside. Preferably, the upper surface of the housing 111 is covered with parylene, which has the advantage of being biocompatible.

[0081] When the medical device is assembled, this housing 111 is positioned on the first surface of the support plate 12.

[0082] The housing 111 is designed to house:

[0083] - a main electronic board 1113 suitable for exchanging power and control signals with a remote control unit, and

[0084] - ultrasonic transducers (which are for example circular, each having a diameter of 10 mm) suitable for generating ultrasonic therapy (or imaging) waves of the brain region of interest.

[0085] Since the electronic boards 1113 and the transducers are known to the person skilled in the art, they will not be described in more detail hereinafter.

[0086] However, the reader will understand that, in addition to the housing 111, the ultrasonic unit 11 can comprise auxiliary receptacles 112, each comprising an auxiliary electronic board and one or more additional transducers.

[0087] The housing 111 and the auxiliary receptacles 112 are distributed so as to form a regularly spaced array of transducers. The auxiliary electronic boards can be connected to the main electronic board 1113 via rigid-flexible connectors 113 for transmitting power supply and control signals from an external control unit (not shown). As Figure 1 The housing 111 and the receptacles 112 extend under the support plate 12, the size of which is chosen to cover the ultrasonic unit 11, the support plate being intended to be attached at its edges to the skull of the patient.

[0088] 2.2. Connection terminal

[0089] An electrical connection terminal 114 is attached to the housing 111. The electrical connection terminal 114 makes it possible to connect the medical device 1 to an external control unit which supplies electrical energy to the transducer and adjusts the operating parameters of the transducer.

[0090] As mentioned above, the connection terminal is adapted to cooperate with the transdermal piercing needle of the connection device.

[0091] More particularly, the connection terminal 114 comprises a pin 1141 which projects outwardly from the housing 111 in a direction perpendicular to the bottom 1111 and which is oriented toward the upper surface of the housing 111 from the bottom 1111.

[0092] The base of the pin preferably comprises a stop 1146 on which the support plate 12 is intended to bear. This makes it possible to maintain a non-zero distance between the housing 111 of the ultrasound unit 11 and the support plate 12 in order to limit contact between the housing 111 and the support plate 12. This makes it possible to avoid damaging the parylene layer which covers the upper surface of the housing 111.

[0093] The upper wall 1142 of the pin 1141 comprises a blind hole 1143 into which the end of the piercing needle of the connection device is intended to be introduced in order to electrically connect the ultrasound unit 11 to the electrical connection device.

[0094] Advantageously, the connection terminal 114 can comprise a conical flared mouth (or countersink) 1144 made at the entrance to the blind hole 1143. This facilitates the introduction of the end of the piercing needle into the blind hole 1143. Indeed, as mentioned above, the connection terminal 114 is covered by the skin of the skull. Thus, during the electrical connection phase of the medical device 1 with the control unit, it can be difficult for the practitioner to introduce the end of the piercing needle into the blind hole 1143. The presence of the countersink 1144 can facilitate this connection operation, the conical flared mouth making it possible to guide the piercing needle toward the blind hole 1143 when the end of the piercing needle is close to the blind hole 1143.

[0095] As Figure 2 illustrated, the side wall of the pin 1141 can comprise a thread 1145. This thread is intended to cooperate by screwing with a corresponding thread provided on the inner surface of the conduit of the attachment piece. This makes it possible to ensure the fixing of the ultrasound unit 11, the support plate 12 and the attachment piece 13 during the assembly of the medical device 1. The cooperation of the ultrasound unit 11 by screwing with the attachment piece 13 makes it possible to distribute the force exerted on the connection terminal by the piercing needle during the connection phase of the intracranial device with the control unit over the entire surface of the support plate 12.

[0096] 3. Support plate

[0097] With reference to Figure 3 An example of a support plate 12 is illustrated.

[0098] The support plate 12 is generally rectangular, but can have any shape, for example circular, triangular or square. The dimensions (length and width) of the support plate 12 can be comprised between 1 and 15 centimeters.

[0099] The support plate 12 can be generally planar. Alternatively, the support plate 12 can be curved or deformed to follow the curvature of the skull of the patient.

[0100] In Figure 3 In the illustrated embodiment, the support plate 12 comprises a plurality of through holes 121. These through holes can be of different shapes (circular, triangular, elliptical, pentagonal, hexagonal, honeycomb, rhomboidal, etc.). The through holes 121 can be obtained by drilling, chemical cutting, molding a solid plate or by weaving a wire, in particular a metal wire, to form a mesh structure consisting of a mesh of wires. The presence of through holes in the support plate contributes to the deformation of the support plate to conform to the shape of the skull of the patient. In other embodiments, the support plate 12 can be a solid plate without through holes 121.

[0101] In all cases, the support plate 12 comprises a through opening 122 for passing the pin through the connection terminal. As Figure 3 illustrated, the through opening 122 is offset with respect to the center of gravity 123 of the support plate. More particularly, the through opening 122 is formed in the support plate 12 so as to extend close to one (or more) border 124 of the support plate 12. This makes it possible to limit the risk of mechanical deformation of the support plate 12 when inserting the lancet into the connection terminal to electrically connect the implantable medical device to the remote control unit.

[0102] The edge 125 of the through opening 122 can be covered with a layer of polymeric material, for example silicone. In this case, the layer of polymeric material is deposited on the edge 125 during assembly of the implantable medical device 1. This layer of polymeric material makes it possible to limit the risk of play between the connection terminal 114 and the attachment piece 13.

[0103] The material constituting the support plate 12 can be a metal, for example titanium or any other metal known to the person skilled in the art (optionally covered with a parylene or the like if the metal used is not biocompatible per se). The use of a metal plate makes it possible to limit its deformation in response to the application of a bearing force (for example a mechanical deformation of less than 2.5 mm in response to a bearing force of 50 Newtons applied to the center of the plate). The use of titanium has many advantages, titanium being a very strong material and being well accepted by the bone structure.

[0104] 4. Attachment

[0105] With reference to Figure 4 , the attachment piece 13 comprises:

[0106] - a conduit 131 able to accommodate the pin 1141, and

[0107] - a peripheral collar 132.

[0108] The conduit is intended to cooperate with the connection terminal to block the support plate between the ultrasound unit and the attachment. More particularly, the conduit comprises a threaded hole of a nut intended to cooperate by threading with the threading 1145 of the lateral wall of the pin 1141. In other words, the internal surface of the conduit 131 comprises a threading 1312 complementary to the threading 1145 of the lateral wall of the pin 1141.

[0109] The collar 132 extends at the base of the conduit 131 and is perpendicular to the rotation axis of the conduit 131. The collar 132 is intended to contact a second surface of the support plate 12 opposite the first surface facing the housing 111. When the ultrasound unit 11, the support plate 12 and the attachment 13 are connected, the collar 132 makes the support plate 12 press against the stop 1146.

[0110] The ratio between the width L Coll of the collar 132 and the width L Cond of the conduit can be between 1 / 4 and 2, preferably between 1 / 2 and 3 / 2, and even more preferentially equal to 1. More particularly, with reference to Figure 1 , the dimensions of the collar 132 are chosen to be sufficient to make the assembly comprising the surface covered by the conduit and the surface of the collar 132 cover almost entirely (i.e. at least 2 / 3) the upper surface of the housing 111. In particular, the ratio between the width L Coll of the collar 132 and the width L Log of the upper surface of the housing 111 (i.e. the diameter in the case of an annular collar and / or a circular housing, the diagonal between two opposite vertices in the case of a parallelepipedic collar and / or a parallelepipedic housing, etc.) is between 1 / 2 and 2, and preferably between 2 / 3 and 1. This makes it possible to have a collar 132 whose surface is sufficient to protect the electronic board 1113 from possible damage caused by the end of the lancet in the case where the practitioner inserts the lancet at a position deviating from the blind hole 1143.

[0111] Preferentially, the shape of the collar 132 is circular. This makes it possible to better distribute the force exerted by the lancet during the introduction of the lancet into the blind hole 1143 of the connection terminal 114.

[0112] Advantageously, the collar 132 can comprise two (or more) radially opposite through-lumens 1321. These lumens 1321 make it easier to screw the attachment 13 to the pin 1141. These lumens also make it possible to apply a predetermined screwing torque during manufacturing, so as to avoid any loss of sealing of the implantable device. Indeed, the pin 1141 is made of two parts (the first part is mounted below the bottom of the housing, the second part is mounted above the bottom, the seal (which must be compressed during assembly) being arranged between the two parts).

[0113] The principle of assembly of the implantable device 1 is as follows. The operator inserts the pin 1141 of the connection terminal 114 into the through-opening 122 of the support plate 12. Once the ultrasound cell 11 is positioned on the first face of the support plate 12, the operator deposits a layer of polymeric material (for example, silicone) on the support plate, in particular at the edge 125 of the through-opening 122. Then, the operator arranges the attachment 13 to the connection terminal 114. The attachment 13 is mounted to the pin 1141 so that the base of the conduit 131 (at which the collar 132 extends) faces the second face of the support plate 12 (which is opposite the first face). Then, the operator screws the connection 13 to the pin 1141 using a tool (not shown) that cooperates with the lumens 1321 formed in the collar 131. The screwing of the attachment 13 causes the collar 132 to be pressed against the support plate 12, which is pressed against the stop 1146 of the connection terminal 114: the ultrasound cell 11, the support plate 12 and the attachment then become one. The implantable device 1 as shown in Figure 1 is thus obtained.

[0114] 5. CONCLUSION

[0115] The implantable device 1 makes it possible to treat and / or image a brain region of interest.

[0116] The presence of the collar 132 of the attachment 13:

[0117] - on the one hand, makes it possible to protect the main electronic board 1113 from any damage that could be caused by the needle when it is inserted under the skin of the skull of the patient,

[0118] - on the other hand, makes it possible to limit the deformation of the support plate 12 by distributing the force exerted by the end of the needle on a larger surface of the support plate 12.

[0119] The reader will understand that many modifications can be made to the application described above without materially departing from the novel teachings and advantages presented herein.

[0120] For example, in the various embodiments described above, the support plate is made of metal. It will be obvious to a person skilled in the art that the support plate can be made of other materials than metal, for example:

[0121] - a polymeric material, such as polyethylene, polystyrene, acrylic, polyether ether ketone (PEEK) or poly(methyl methacrylate) (PMMA),

[0122] - a thermoplastic elastomer, such as PEBAX.

[0123] Similarly, in the different embodiments described above, the ultrasonic unit 11, the support plate 12 and the attachment 13 are connected together by screwing the attachment 13 to the pin 1141 of the ultrasonic unit 11. Obviously, other attachment methods (gluing, press fitting, etc.) for connecting the support plate 12 to the ultrasonic unit 11 can be provided.

Claims

1. An implantable device (1) intended to be positioned in a hole provided in the skull of a patient, the implantable device (1) comprising: - a support plate (12) comprising a first surface and a second surface opposite the first surface, - an ultrasound cell (11) intended to be mounted to the support plate (12), the ultrasound cell (11) comprising: • a housing (111) comprising a bottom (1111), at least one lateral wall (1112) and an upper surface opposite the bottom (1111), the housing (111) being intended to be positioned on the first surface of the support plate (12), • a plurality of transducers provided in the housing (111) for generating ultrasound waves for treating a brain disease, • an electrical connection terminal (114) attached to the housing (111) for connecting the ultrasound cell (11) to a remote control unit via an electrical connection device, characterized in that: - the connection terminal (114) comprises a pin (1141) which projects outwardly from the housing (111) in a direction perpendicular to the bottom (1111) and is oriented from the bottom (1111) towards the upper surface of the housing (111), - the support plate (12) comprises a through opening (122) through which the pin (1141) passes, - the implantable device (1) further comprises an attachment piece (13) comprising: • a conduit (131) adapted to accommodate at least a portion of the pin (1141), and • a surrounding collar (132) extending perpendicular to the longitudinal axis of the conduit (131), when the ultrasound cell (11), the support plate (12) and the attachment piece (13) are connected, the collar (132) is intended to contact the second surface of the support plate (12) to press the support plate (12) against the housing (111), wherein the pin (1141) comprises an upper wall (1142) opposite the bottom (1111) of the housing (111) and a blind hole (1143) intended to accommodate one end of the connection device, the upper wall (1142) comprising a counterbore (1144) made at the entrance of the blind hole (1143). The collar (132) is circular in shape.

2. The implantable device of claim 1, wherein, The ratio between the width (L Coll ) of the collar (132) and the width (L Cond ) of the conduit (131) is comprised between 1 / 4 and 2.

3. The implantable device of claim 1, wherein, The ratio between the width (L Coll ) of the collar (132) and the width (L Log ) of the upper surface of the housing (111) is between 1 / 2 and 2.

4. The implantable device of any of claims 1-3, wherein, The collar (132) comprises at least two diametrically opposite through lumens (1321).

5. The implantable device of claim 1, wherein, The pin (1141) is cylindrical in shape and comprises a thread (1145) on its lateral wall, the conduit (131) consisting of a nut whose threaded hole is intended to cooperate by screwing with the thread (1145) of the lateral wall of the pin (1141).

6. The implantable device of claim 1, wherein, The pin (1141) comprises a stop (1146) at its base, the edge of the through opening (122) of the support plate (12) being intended to press against the stop (1146) when the pin (1141) is inserted in the through opening (122).

7. The implantable device of claim 1, wherein, The edge of the through opening (122) of the support plate (12) is covered with a layer of polymeric material of silicone.

8. The implantable device of claim 1, wherein, The distance between the center of the through opening (122) and the center of gravity (123) of the support plate (12) is not zero.

9. The implantable device of claim 1, wherein, ​ 10. The implantable device of claim 2, wherein, The ratio is between 1 / 2 and 3 / 2.

11. The implantable device of claim 2, wherein, The ratio is equal to 1.

12. The implantable device of claim 3, wherein, The ratio is between 2 / 3 and 1.

13. A system for imaging and / or treating brain tissue, the system comprising a control unit and an electrical connection device, characterized in that The system further comprises an implantable device (1) according to any one of claims 1 to 10.

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