Intracranial brain tissue retractor

Abstract

An intracranial brain tissue retractor comprising a positioning member for attachment to the rim of a skull window and a catheter member passing through a through-hole of the positioning member into a brain ventricle and reaching a lesion for establishing a passage for a treatment instrument, the catheter member comprising an inner tube and an outer tube allowing relative axial movement, the positioning member locking the catheter member by the outer tube, a distal end of the outer tube being configured with an expandable formation which is switched to a collapsed state by elastic deformation and to a first expanded state by elastic return; the distal end of the inner tube being radially inwardly drawn to the expandable formation to force the expandable formation to elastically deform to switch to the collapsed state and to release the expandable formation to allow the expandable formation to elastically return to switch to the first expanded state by driving the inner tube axially reciprocally relative to the outer tube at the proximal end.

Description

Technical Field

[0001] This invention relates to a device for retracting human tissue, and more particularly to an intracranial brain tissue retractor. Background Technology

[0002] Before performing medical procedures on lesions in the intracranial brain tissue (such as biopsy to obtain brain tissue, removal of lesions in the brain tissue, suturing of brain tissue, etc.), it is usually required to retract (or stretch) the brain tissue around the lesion to provide sufficient operating space and field of vision for the medical instruments (such as biopsy forceps, scalpels, staplers, endoscopes, etc.).

[0003] Two typical devices for retracting intracranial brain tissue are provided in the prior art.

[0004] The first type of retraction device includes a catheter with a small length-to-diameter ratio that allows radial expansion of the catheter body and a positioning component for attaching the proximal end of the catheter. The positioning component is pre-fixed to the edge of a pre-existing bone window in the skull by bone screws. The catheter, in a radially constricted state, extends through the bone window into the brain tissue, with its proximal end attached to the positioning component. Before medical treatment, the catheter is radially expanded to retract the brain tissue it passes through, thereby exposing the lesion on the distal side of the catheter. Therefore, the treatment device reaching the lesion via the catheter can obtain sufficient operating space and observation field. However, a typical drawback of this retraction device is that because the entire catheter undergoes radial expansion, all the brain tissue it passes through is retracted. However, because the risk of damage to deep brain tissue in certain areas may increase due to the expansion of the catheter, this retraction device is mostly suitable for situations where the lesion is located in superficial brain tissue and only superficial brain tissue needs to be retracted to expose the lesion.

[0005] The second type of retraction device includes a linear catheter component with a large length-to-diameter ratio and a positioning component. The positioning component is pre-fixed to the edge of a bone window in the skull. The distal end of the catheter component extends through the bone window into the ventricle and reaches the lesion located in the deep brain tissue. Once the distal end of the catheter component reaches the lesion, the proximal end of the catheter component is locked by the positioning component to prevent displacement of the distal end. Thus, the catheter component constructs a pathway for the distal end of the rod-like treatment device to reach the lesion. An expandable structure is configured at the distal end of the catheter component. After the distal end of the catheter component reaches the lesion and the proximal end is locked by the positioning component, the expandable structure expands radially to retract the brain tissue surrounding the lesion. Since the expandable structure is only configured at the distal end of the catheter component and expands only at the distal end, the catheter body does not expand. Therefore, this retraction device only retracts the brain tissue surrounding the lesion that needs to be retracted, while other brain tissues traversed by the catheter component are not retracted. This reduces the risk of damage to the brain tissue traversed by the catheter component. To control the switching between expansion and retraction of the expandable structure at the distal end of the catheter component, existing technology configures the catheter component as having an inner tube and an outer tube fitted over the inner tube, allowing relative axial movement between the inner and outer tubes. The expandable structure is located at the distal end of the inner tube. When not constrained by the outer tube, the expandable structure is in a conical expanded state; when constrained by the outer tube, the expandable structure is forced to retract into the outer tube. The expansion and retraction of the expandable structure can be controlled in two specific ways. The first method involves the operator driving the inner tube proximally towards the distal end relative to the outer tube, causing the expandable structure at the distal end of the inner tube to extend from the distal end of the outer tube. During this extension, the expandable structure expands radially as it is released from the constraint of the outer tube, thereby retracting the brain tissue. The expandable structure is then retracted back into the outer tube by driving the inner tube proximally towards the proximal end relative to the outer tube, switching to a closed state (this method is disclosed in Chinese patent application number 201880018323X). The drawback of this method is that while the expandable structure generates radial expansion that is beneficial for retracting the brain tissue when it extends from the distal end of the outer tube, it also generates axial movement relative to the brain tissue. That is, the expandable structure expands radially while also moving axially relative to the brain tissue. This expansion method obviously increases the probability or degree of damage to the brain tissue surrounding the lesion.The second method involves the operator driving the outer tube proximally relative to the inner tube, axially moving it to expose the expandable structure distal to the inner tube. This releases the constraint on the expandable structure, causing it to expand radially to retract the brain tissue. Driving the outer tube distally then causes it to re-enclose the expandable structure, forcing it to retract. During this retraction, because the inner tube and expandable structure do not move axially relative to the brain tissue, the expandable structure only expands radially, thus reducing the probability or extent of brain tissue damage during expansion. However, this method has a drawback: because the positioning component locks the catheter component via the outer tube, axial movement of the outer tube could lead to... First, the locking of the proximal end of the outer tube must be released to allow the outer tube to move. However, when the outer tube is driven, the distal end of the duct component may shift because it is in a free state. This may require readjustment and repositioning of the duct component after the outer tube moves to correct the shift. Furthermore, the duct component can only be adjusted and repositioned when the expandable structure is in an expanded state, which may cause damage to the brain tissue in the retracted area. In addition, when driving the outer tube to move, the inner tube must be kept stationary. Therefore, a structure for positioning the inner tube through the outer tube is also required on the positioning component. This makes the structure of the positioning component more complex and the operation of retracting the brain tissue more complex. Therefore, this method is rarely used in the prior art to control the expansion and contraction of the expandable structure. Summary of the Invention

[0006] In view of the above-mentioned technical problems existing in the prior art, the present invention provides an intracranial brain tissue retractor.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: An intracranial brain tissue retractor includes a positioning component for attaching to the edge of a bone window in the skull and a catheter component that enters the ventricle and reaches the lesion through a through-hole in the positioning component to establish a pathway for a treatment device. The catheter component includes an inner tube and an outer tube that allow relative axial movement. The positioning component locks the catheter component through the outer tube. The distal end of the outer tube is configured with an expandable structure. The expandable structure switches to a closed state by means of elastic deformation and switches to a first expanded state by means of elastic reset. By driving the inner tube to move axially back and forth relative to the outer tube at the proximal end, the distal end of the inner tube is radially pulled inward to force the expandable structure to elastically deform and switch to the contracted state, and the expandable structure is released to allow the expandable structure to elastically reset and switch to the first expanded state.

[0008] Preferably, The expandable structure includes a plurality of main linear rods arranged circumferentially along the wall of the outer tube and extending axially. By configuring each main linear rod to be in a radially outward bending state in the reset state, the expandable structure is switched to the first expansion state by means of elastic reset. Each main linear rod has a meshing strip extending along its length on its radially inner side. The outer wall of the inner tube at its distal end has meshing grooves that mate with the meshing strips of each main linear rod. By driving the inner tube to move towards the distal end, the meshing strips slide into the meshing grooves, thereby pulling each main linear rod radially inward and forcing each main linear rod to elastically deform radially inward, so that the expandable structure switches from the first expanded state to the contracted state. By driving the inner tube to move towards the proximal end, the meshing strips are ejected from the meshing grooves, thereby releasing the pull on each main linear rod and allowing each main linear rod to elastically reset radially outward, so that the expandable structure switches from the contracted state to the first expanded state.

[0009] Preferably, secondary linear rods are provided on both sides of each primary linear rod; the secondary linear rods are attached and fixed to the distal end of the primary linear rods at their distal ends, and notches are provided on the secondary linear rods by removing material so that the secondary linear rods can be bent radially outward; the distal end of the inner tube has a plurality of protrusions on its tube wall having force-applying surfaces facing the proximal ends of each secondary linear rod, and by driving the inner tube, which has switched the expandable structure to the retracted state, to move towards the distal end, the force-applying surfaces of each protrusion push against the proximal ends of each secondary linear rod to force each secondary linear rod to bend radially outward, thereby switching the expandable structure from the retracted state to the second expanded state.

[0010] Preferably, a tongue with a free end is obtained by cutting on the wall of the inner tube at the distal end. The protrusion protruding from the outer circumferential surface of the inner tube wall is obtained by bending the tongue radially outward. Thus, when the inner tube is driven to move towards the proximal end to switch the expandable structure from the contracted state to the first expanded state, the outer tube can force the protrusion to elastically deform radially inward and retract into the outer tube.

[0011] Preferably, the main linear rod includes a front straight segment on the distal side, a rear straight segment on the proximal side, and a curved segment between the front and rear straight segments; wherein: The secondary linear rods are located on both sides of the front straight segment of the primary linear rod.

[0012] Preferably, The secondary linear rod has two expansion segments separated by three notches, and the two expansion segments form a triangular expansion configuration by bending and deforming radially outward; or The secondary linear rod has three expansion segments separated by four notches, and the three expansion segments form a trapezoidal expansion configuration by bending and deforming radially outward.

[0013] Preferably, the intracranial brain tissue retractor further includes a sealing component, the sealing component comprising a shaft and a sealing plug attached to the distal end of the shaft, wherein the shaft is located in the inner tube during the insertion of the catheter component into the ventricle, and the sealing plug is located at the distal end of the catheter component to seal the distal port of the expandable structure.

[0014] Preferably, the radially outer side of the expandable structure is covered with an elastic membrane; wherein: The proximal end of the elastic membrane is attached to the proximal end of each main linear rod of the expandable structure, and the distal end of the elastic membrane is attached to the distal end of each main linear rod.

[0015] Preferably, an axially extending perforated slot is formed on the wall of the outer tube near its proximal end. A lower wrench is fixed to the wall of the outer tube on the distal side of the perforated slot, and an upper wrench is fixed to the wall of the inner tube opposite to the perforated slot. The upper wrench is positioned opposite the lower wrench through the perforated slot. By holding the lower wrench and turning the upper wrench, the inner tube is driven to move relative to the outer tube. When the upper wrench moves to the proximal side of the perforated slot, the inner tube moves to a position that switches the expandable structure to a first expansion state. When the upper wrench moves to the distal side of the perforated slot, the inner tube moves to a position that switches the expandable structure to a second expansion state. A sliding stop that allows circumferential sliding is installed on the wall of the outer tube on one side of the circumferential direction of the hollowed-out slot, and a notch is opened on the side of the sliding stop in the circumferential direction; the wall of the outer tube on the other side of the circumferential direction of the hollowed-out slot is engraved with scale lines to indicate the position of the upper wrench in the first expanded state, the retracted state, and the second expanded state of the expandable structure, and the notch corresponds to the scale line indicating the retracted state; by pushing the sliding stop towards the hollowed-out slot, the sliding stop positions the upper wrench in its axial position.

[0016] Preferably, both ends of the main linear rod are provided with radially penetrating rivet holes. By injecting water-based colloid into the rivet holes and wetting or permeating the elastic membrane and then curing it, the colloid forms rivets that attach the elastic membrane to the main linear rod.

[0017] Preferably, a silicone cap is fitted onto the distal end of each of the main linear rods.

[0018] Compared with the prior art, the beneficial effects of the intracranial brain tissue retractor disclosed in this invention are: 1. The retractor provided by the present invention has an expandable structure disposed at the distal end of the outer tube, and the axial movement of the inner tube controls the switching of the expansion state of the expandable structure. The outer tube is fixed by a positioning component. Therefore, the expandable structure will not move axially when switching the expansion state, thereby significantly reducing the probability and degree of damage to the brain tissue surrounding the lesion caused by the switching of the expansion state. Moreover, the pathway established by the duct component will not shift before and after the state switching, so there is no need to reposition the duct component.

[0019] 2. The retractor of the present invention provides two expandable states with different expansion amounts, thereby meeting the requirements of medical treatment programs for different retraction amounts of brain tissue, and the switching process only requires changing the movement direction of the inner tube, making the operation simple.

[0020] 3. The operating mechanism used by the operator to switch the state of the expandable structure has both the function of switching the expansion state of the expandable structure and the function of positioning, and has a simple structure and is easy to operate.

[0021] 4. The sealing plug used to seal the far port of the expandable structure is compliant, thereby facilitating exit from the expandable structure.

[0022] 5. Other advantages of the present invention are described directly or implicitly in the specific embodiments described in the specification.

[0023] The overview of various implementations or examples of the technology described in this invention is not a complete disclosure of the full scope or all features of the disclosed technology. Attached Figure Description

[0024] In drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with or without letter suffixes may indicate different instances of similar parts. The drawings generally illustrate various embodiments by way of example rather than limitation and, together with the description and claims, serve to explain embodiments of the invention. Where appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and not intended to be exhaustive or exclusive embodiments of the apparatus or method.

[0025] Figure 1 A state view of the puller provided by the present invention (the expandable structure is in the retracted state).

[0026] Figure 2 for Figure 1 A magnified view of part A.

[0027] Figure 3 for Figure 1 A magnified view of part B.

[0028] Figure 4 This is a three-dimensional structural diagram of the distal end of the inner tube in the conduit assembly.

[0029] Figure 5 This is a front sectional view of the distal end of the sealing component.

[0030] Figure 6 A schematic diagram of a three-dimensional structure in the first expansion state for an expandable construction.

[0031] Figure 7 A state view of the retractor provided by the present invention (the expandable structure is in the first expanded state).

[0032] Figure 8 for Figure 7 A magnified view of part C.

[0033] Figure 9 This is a schematic diagram of the three-dimensional structure of the secondary linear rod.

[0034] Figure 10 A state view of the retractor provided by the present invention (the expandable structure is in the second expanded state).

[0035] Figure 11 for Figure 10 A magnified view of part D.

[0036] Figure label: 100-Conduit component; 10-Inner tube; 11-Matching groove; 12-Protrusion; 121-Force application surface; 20-Outer tube; 21-Flare mouth; 22-Hollowed groove; 30-Expandable structure; 31-Main linear rod; 311-Matching strip; 312-Rivet hole; 313-Rear straight section; 314-Bent section; 315-Front straight section; 32-Secondary linear rod; 321-Notch; 40-Silicone cap; 50-Elastic membrane; 60-Operating mechanism; 61-Lower wrench; 62-Upper wrench; 63-Slide stop; 631-Notch; 70-Sealing component; 71-Sealing plug; 711-Cavity; 72-Shaft; 200-Positioning component; 300-Treatment device. Detailed Implementation

[0037] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0038] To keep the following description of the embodiments of the present invention clear and concise, detailed descriptions of known functions and known components are omitted.

[0039] This invention discloses an intracranial brain tissue retractor. This retractor is used to establish a pathway for a treatment device 300 to reach an intracranial lesion and to retract the brain tissue surrounding the lesion to provide sufficient operating space for the treatment device 300 and sufficient field of vision for the operator. The retractor disclosed in this invention is particularly suitable for situations where the lesion is located deep within the intracranial cavity and only allows the treatment device 300 to enter through the skull to establish a pathway, such as when the lesion is located in the thalamus, basal ganglia, pineal gland, or third ventricle. The retractor provided by this invention: on the one hand, aims to retract the brain tissue surrounding the lesion; on the other hand, it particularly aims to reduce damage to the brain tissue during the retraction process; furthermore, it particularly aims to provide two expansion states with different amounts of expansion to meet different retraction requirements of the brain tissue; other aspects also aim to avoid displacement of the pathway before, after, and distal to the retraction of the surrounding brain tissue; and to reduce damage to the brain tissue traversed during the process of reaching the lesion through the brain tissue.

[0040] Before introducing the retractor of the present invention, the descriptions of “proximal,” “proximal side,” “distal,” and “distal side” of the components and structures of the retractor in the following text are defined as follows: “proximal” or “proximal side” refers to the end or side located or facing the extracranial region (or the operator), and “distal” or “distal side” refers to the end or side located or facing the lesion.

[0041] like Figures 1 to 11As shown, the retractor includes a positioning component 200 and a catheter component 100. The positioning component 200 is pre-attached to a bone window (not shown in the figures) opened on the skull. The distal end of the catheter component 100 enters the intracranial cavity through a through-hole in the positioning component 200, and then reaches the lesion area through the intracranial brain tissue. Thus, the catheter component 100 establishes a pathway for the treatment device 300 to reach the lesion from outside the skull. The distal end of the treatment device 300 reaches the lesion from the proximal port of the catheter component 100 through a tube hole in the catheter component 100. In this invention, the treatment device 300 is rod-shaped and allows passage through the tube hole of the catheter component 100. The types of treatment devices 300 include, but are not limited to: endoscopes for providing a field of view, scalpels for removing lesions, ultrasonic scalpels for emulsifying lesions, and biopsy needles for obtaining tissue.

[0042] The catheter component 100 includes an inner tube 10 and an outer tube 20. The outer tube 20 is fitted over the inner tube 10 and allows the inner tube 10 to move axially relative to the outer tube 20. A keyway structure between the outer tube 20 and the inner tube 10 restricts their relative rotation. After the distal end of the catheter component 100 reaches the predetermined area of ​​the lesion, the positioning component 200 fixes the outer tube 20, for example, using a set screw or locking sleeve, thereby positioning the pathway established by the catheter component 100. Thus, the orifice of the inner tube 10 serves as the orifice of the catheter component 100 for the insertion of the treatment instrument 300; and because the outer tube 20 is fixed by the positioning component 200, the movement of the inner tube 10 relative to the outer tube 20 does not cause overall displacement of the catheter component 100, and therefore, the axial movement of the inner tube 10 does not cause displacement of the established pathway. Preferably, a flared opening 21 is provided at the proximal end of the outer tube 20 to facilitate the smooth insertion of the treatment device 300 and the sealing component 70, which will be described below, into the bore of the inner tube 10 from the proximal end.

[0043] In this invention, the expandable structure 30 for retracting brain tissue around the lesion is located at the distal end of the outer tube 20 rather than the distal end of the inner tube 10. Specifically, the expandable structure 30 includes a plurality of linear rods arranged circumferentially along the wall of the outer tube 20. To distinguish them from the secondary linear rods 32 described below, these linear rods may be referred to as primary linear rods 31. In the free state, i.e., when the linear rods are not subjected to radial force, such as... Figure 6 and Figure 8 As shown, each main linear rod 31 is in a radially outward bending state. Therefore, in this state, the expandable structure 30 formed by the circumferentially arranged main linear rods 31 is in an expanded state with a radial dimension much larger than the outer diameter of the outer tube 20. To distinguish it from the second expansion state described below, this expansion state may be referred to as the first expansion state. Thus, in this state, the distal end of the catheter component 100 uses the expandable structure 30 to pull away the brain tissue around the lesion.

[0044] like Figure 6 As shown, each main linear rod 31 has a fitting strip 311 extending along its length to its proximal and distal ends on its radially inner side, as... Figure 4 As shown, on the outer circumferential surface of the distal section of the inner tube 10, there are axially extending grooves 11 that match the matching strips 311 of each main linear rod 31. The matching of the matching strip 311 with the groove 11 means that the matching strip 311 is allowed to slide along the groove 11 while restricting the matching strip 311 that has slid into the groove 11 from radially separating relative to the groove 11. Thus, during the process of applying force towards the distal end of the inner tube 10 to move it, the matching strips 311 on the inner side of each main linear rod 31 gradually enter the matching grooves 11 on the outer circumferential surface of the distal section of the inner tube 10 from the proximal section to the distal section, thereby causing each main linear rod 31 to elastically deform radially inward. Finally, as... Figure 1 and Figure 2 As shown, the radial dimension of the expandable structure 30 formed by the elastically deformed main linear rods 31 is basically consistent with the outer diameter of the outer tube 20. Therefore, the expandable structure 30 switches from the first expanded state to the contracted state by moving the inner tube 10 towards the distal end. During the process of applying force towards the proximal end to the inner tube 10, causing the inner tube 10 to move towards the proximal end, the inner fitting strips 311 of each main linear rod 31 gradually emerge from the fitting grooves 11 at the distal end of the inner tube 10 from the distal section to the proximal section, thereby gradually releasing the inner tube 10 from the tension on the main linear rods 31. Figure 7 and Figure 8 As shown, the main linear rod 31 is able to return to its radially outward bent state by means of elastic reset, thereby allowing the expandable structure 30 to switch from a contracted state to a first expanded state by means of the movement of the inner tube 10 distally. The operation of driving the inner tube 10 to move axially relative to the outer tube 20 is performed at the proximal end of the conduit component 100 by means of the operating mechanism 60 described below.

[0045] Before establishing access using catheter component 100, such as Figure 1 As shown, the distal end of the inner tube 10 needs to be kept in a state extending beyond the distal end of the outer tube 20, thereby keeping the expandable structure 30 in a retracted state. This allows the distal end of the catheter component 100 to smoothly pass through the through-hole of the positioning component 200 and the intracranial brain tissue to reach the lesion area. After the distal end of the catheter component 100 reaches the lesion area and the outer tube 20 is fixed by the positioning component 200 to locate the established pathway, if it is necessary to retract the brain tissue around the lesion, such as... Figure 7As shown, only the inner tube 10 needs to be driven to retract its distal end into the outer tube 20, thereby switching the expandable structure 30 from the retracted state to the first expanded state, thus retracting the surrounding brain tissue. Since the switch of the expandable structure 30 to the first expanded state is not accompanied by axial movement of the outer tube 20, the main linear rods 31 forming the expandable structure 30 do not undergo axial movement as a whole, thus significantly reducing the probability and extent of damage to the brain tissue surrounding the lesion during the expansion process. Since the switching of the expansion state of the expandable structure 30 is handled by the inner tube 10, and the outer tube 20 is always fixed by the positioning component 200, the switching of the expansion state of the expandable structure 30 does not cause displacement of the established pathway, and there is no need to readjust the overall orientation of the catheter component 100 when switching the expansion state.

[0046] In some preferred structures, such as Figure 2 and Figure 9 As shown, secondary linear rods 32 are arranged on both sides of each main linear rod 31. When the expandable structure 30 is in the retracted state, the secondary linear rods 32 are forced to bend radially outward as a whole by moving the distal end of the inner tube 10 toward the distal end of the expandable structure 30 (or the distal end of the main linear rod 31). Figure 10 and Figure 11 As shown, this allows the expandable structure 30 to switch from a retracted state to a second expanded state defined by the radially outwardly bent secondary linear rods 32. The radial expansion achievable in this second expanded state is less than that in the first expanded state. Specifically, the main linear rod 31 includes a front straight segment 315 located at the distal end, a rear straight segment 313 located at the proximal end, and a curved segment 314 between the front straight segment 315 and the rear straight segment 313, as shown. Figure 2As shown, the distal end of the inner tube 10 reaches the front straight section 315 through the bent sections 314 of each main linear rod 31 of the expandable structure 30, forcing the bent sections 314 to straighten and maintaining the expandable state in the contracted state; the secondary linear rods 32 are arranged on both sides of the front straight section 315, and the distal ends of the secondary linear rods 32 are fixed to the distal ends of the front straight section 315; a key is provided on the side wall of the proximal end of the secondary linear rod 32, and a groove is provided on the side wall of the main linear rod 31. The key is located in the groove and can slide along the groove. The mating method of the key and the groove can be configured to mate with the aforementioned mating strip 311 and mating groove 11. In a similar manner, the proximal end of the secondary linear rod 32 is restricted from separating from the primary linear rod 31, and the sidewall of the middle section of the secondary linear rod 32 maintains a certain gap with the sidewall of the primary linear rod 31 to avoid interference by the primary linear rod 31 when bending radially outward; notches 321 are configured on the secondary linear rod 32 by removing material to allow the secondary linear rod 32 to bend radially outward. Specifically, for example, the secondary linear rod 32 has two expansion sections separated by three notches 321, and the two expansion sections form a triangular expansion configuration (not shown in the figure) by bending radially outward. For further example, such as... Figure 9 and Figure 11 As shown, the secondary linear rod 32 has three expansion segments separated by four notches 321. These three expansion segments form a trapezoidal expansion configuration by bending and deforming radially outwards. For example... Figure 2 , Figure 4 and Figure 11 As shown, the distal end of the inner tube 10 has multiple protrusions 12 on its wall, each having a force-applying surface 121 facing the proximal end of each sublinear rod 32. Thus, if it is only necessary to retract brain tissue to a certain space without retracting a large space around the lesion by switching the expandable structure 30 to the first state, then it is only necessary to push the inner tube 10 toward the distal end of the expandable structure 30. During the movement of the distal end of the inner tube 10 toward the distal end of the expandable structure 30, as... Figure 11As shown, the protrusion 12 protruding from the outer peripheral surface of the distal end of the inner tube 10 pushes against the end face of the proximal end of the sublinear rod 32 by means of the force-applying surface 121 thereon, so that the proximal end of the sublinear rod 32 slides toward the distal end, thereby forcing each sublinear rod 32 to deform at each notch 321 and generate radial outward expansion, thereby switching to the second expansion state to achieve a smaller degree of retraction of the tissue around the lesion. Preferably, a tongue with a free end is obtained by cutting on the wall of the inner tube 10 at the distal end. A protrusion 12 protruding from the outer circumferential surface of the wall of the inner tube 10 is obtained by bending the tongue radially outward. In this way, when the inner tube 10 is driven to move towards the proximal end and the expandable structure 30 is switched from the retracted state to the first expanded state, the outer tube 20 can force the protrusion 12 to deform radially inward and retract into the outer tube 20. Therefore, there is no need to leave a reserved gap between the inner tube 10 and the outer tube 20 to avoid interference between the protrusion 12 and the outer tube 20 when the inner tube 10 retracts. Thus, the inner tube 10 and the outer tube 20 can be more tightly assembled to suppress the radial runout of the inner tube 10 relative to the outer tube 20.

[0047] As can be seen from the above, the expandable structure 30 of the catheter component 100 of the present invention has two expansion states with different expansion amounts, thereby meeting the needs for different amounts of traction on the brain tissue around the lesion, and the expandable structure 30 can be switched between the contracted state and the two expandable states simply by changing the axial movement direction of the inner tube 10.

[0048] The expandable structure 30 at the distal end of the outer tube 20 can be integrally formed with the outer tube 20 or separately attached. The section with the embedded groove at the distal end of the inner tube 10 can be integrally formed with the main body of the inner tube 10 or separately attached. Both the outer tube 20 and the inner tube 10 are made of biocompatible polymers or metal materials, such as polycarbonate (PC), polyetheretherketone (PEEK), or titanium alloy (Ti6Al4V). Preferably, the expandable structure 30 is made of a metal material such as titanium alloy because metal materials have excellent machinability. The main body of the outer tube 20 is made of a polymer to reduce weight and cost. The expandable structure 30 is detachably attached to the outer tube 20. The distal end of the inner tube 10 is made of an easily machinable metal material such as titanium alloy. The main body of the inner tube 10 is made of a low-weight and low-cost polymer. The distal section of the inner tube 10 is detachably attached to the main body section of the inner tube 10.

[0049] The expandable structure 30 can be manufactured in the following manner: First, circumferentially arranged mating strips 311 are machined on the inner side of the titanium alloy tube by removing material. Then, axially extending notches are machined on the tube wall between each pair of adjacent mating strips 311, and circumferentially arranged main linear rods 31 are divided through the notches. Then, each main linear rod 31 is bent radially outward and shaped by bending and heating at the same time.

[0050] In the preferred configuration with the secondary linear rod 32: the secondary linear rod 32 can be fixed to the main linear rod 31 by welding as a separate component, or the secondary linear rod 32 can be obtained on one side of the main linear rod 31 by cutting.

[0051] In some preferred structures, such as Figure 2 and Figure 8 As shown, the expandable structure 30 is externally covered with an elastic membrane 50 made of silicone material, which has good elastic-plastic deformation. Specifically, the proximal end of the elastic membrane 50 is attached to the proximal end of each main linear rod 31, and the distal end of the elastic membrane 50 is used to attach to the distal end of each main linear rod 31. Thus, when the expandable structure 30 switches from a closed state to a first expanded state or a second expanded state, the elastic membrane 50 expands through elastic-plastic deformation and directly contacts the brain tissue, pulling it away. This avoids direct contact between the main linear rods 31 and the secondary linear rods 32 and the brain tissue, thereby preventing damage to the brain tissue caused by the expansion of the main linear rods 31 and the secondary linear rods 32, such as scratches or local compression. The elastic membrane 50 can be attached to the main linear rods 31 in various ways, for example, by suturing the two together through the suture holes of the elastic membrane 50 and the main linear rods 31. The present invention provides a preferred attachment method: radially through rivet holes 312 are provided at the proximal and distal ends of the main linear rod 31. By injecting colloid into the rivet holes 312 and wetting or passing through the through holes pre-opened in the elastic membrane 50 and curing, the colloid forms a rivet that attaches the elastic membrane 50 to the main linear rod 31 and the secondary linear rod 32. The elastic membrane 50 is attached to the linear rod by means of the rivet.

[0052] In some preferred structures, such as Figure 2 and Figure 8 As shown, each main linear rod 31 and the two secondary linear rods 32 have a silicone cap 40 fitted and adhered to their common distal ends. This silicone cap 40 blunts the distal ends of the linear rods, effectively preventing damage to brain tissue from the distal ends of the linear rods when the expandable structure 30 switches between expanded and retracted states. In particular, it effectively prevents damage to brain tissue from the distal ends of the linear rods when the expandable structure 30 switches to a retracted state. Preferably, the silicone cap 40 is adhered to the distal ends of the linear rods using bio-adhesive.

[0053] In some preferred structures, such as Figure 5 and combined Figure 1 and Figure 2As shown, the retractor is also equipped with a blocking component 70. Before the catheter component 100 extends into the intracranial brain tissue, the blocking component 70 passes through the catheter component 100 and protrudes from the distal end of the catheter component 100 to prevent damage to the brain tissue from the distal end of the catheter component 100 during its penetration into the intracranial brain tissue. Specifically, the blocking component 70 includes a shaft 72 and a blocking plug 71 attached to the distal end of the shaft 72. The blocking plug 71 has a conical or spherical shape, and the radial dimension of the proximal end of the blocking plug 71 is greater than the diameter of the shaft 72 and greater than the outer diameter of the expandable component in the retracted state. Before the catheter component 100 is inserted into the intracranial brain tissue, the operator holds the shaft 72 so that the occluder 71 enters the cannula of the catheter component 100 through the flared end 21 at the proximal end and extends out from the distal port of the expandable structure 30. Because the radial dimension of the proximal end of the occluder 71 is relatively large, it can shield the distal port of the expandable structure 30. Thus, during the insertion of the catheter component 100 into the intracranial brain tissue, the distal end of the catheter component 100 is advanced by the occluder 71, thereby avoiding damage to the distal port of the expandable structure 30. After the distal end of the catheter component 100 reaches near the lesion area, the occluder 71 is pulled out of the catheter component 100 by holding the shaft 72. The extraction procedure is as follows: First, force is applied to move the inner tube 10 proximally a small distance so that the distal port of the expandable structure 30 is enlarged to allow the occluder 71 to retract into the inner hole of the expandable structure 30. Then, force is applied to the shaft 72 to retract the occluder 71 into the inner hole of the expandable structure 30 and pull it out from the proximal end of the catheter component 100 through the tube hole. Preferably, as Figure 5 As shown, the plug 71 is made of silicone material, and a cavity 711 is provided on the inner side of the proximal edge of the plug 71. This allows the outer side of the proximal edge of the plug 71 to conform. Thus, when the plug 71 is pulled out by the hand-held shaft 72, the outer edge of the proximal end of the plug 71 conformally deforms, reducing its radial dimension so that it can smoothly retract into the inner hole of the conduit component 100. This makes the removal process smooth and almost without jamming. Furthermore, the plug 71 with the cavity 711 can further reduce the expansion amount generated by the expandable structure 30 for removing the plug 71.

[0054] In some preferred structures, such as Figure 1 and Figure 3As shown, an operating mechanism 60 for driving the axial movement of the inner tube 10 and positioning the inner tube 10 is configured in the proximal section of the conduit component 100. Specifically, the driving structure is as follows: a rectangular perforated slot 22 is formed on the wall of the proximal section of the outer tube 20. The perforated slot 22 extends axially for a certain length. A lower wrench 61 is fixed on the wall of the outer tube 20 located at the distal end of the perforated slot 22. An upper wrench 62 is fixed on the wall of the inner tube 10 opposite to the perforated slot 22. The upper wrench 62 extends radially out of the conduit component 100 through the perforated slot 22 and is opposite to the lower wrench 61. Thus, by holding the lower wrench and turning the upper wrench 62, the inner tube 10 is driven to move towards the distal end or proximal end of the conduit component 100, thereby controlling the expansion structure 30 to switch between the retracted state and the two expanded states. The positioning structure is as follows: the relationship between the position of the upper wrench 62 and the axial dimension of the perforated slot 22 is configured as follows: Figure 7 As shown, when the upper wrench 62 is pulled to the proximal side of the hollowed-out slot 22, the inner tube 10 just causes the expandable structure 30 to switch to the first expansion state, and, as Figure 10 As shown, when the upper wrench 62 is pulled to the far side of the slot 22, the inner tube 10 just causes the expandable structure 30 to switch to the second expansion state. A sliding stop 63 is installed on the wall of the outer tube 20 on the circumferential side of the slot 22, allowing circumferential sliding. For example, the sliding stop 63 is allowed to slide circumferentially by the cooperation of a groove on the wall of the outer tube 20 and a sliding strip disposed on the inner side of the groove. A notch 631 is provided on the side of the sliding stop 63 near the slot 22. Thus, when the upper wrench 62 needs to be positioned at the desired location, the sliding stop 63 is slid to the slot 22, using the sliding stop 63 to limit the wrench, thereby limiting the inner tube 10 so that the expansion structure remains in the switched state. Specifically, as shown... Figure 7 As shown, when the upper wrench 62 reaches the proximal side of the slot 22 to switch the expandable structure 30 to the first expanded state, the upper wrench 62 is limited by the proximal side of the slide stop 63 by sliding the slide stop 63 to the slot 22, so that the expandable structure 30 remains in the first expanded state; as Figure 10 As shown, when the upper wrench 62 reaches the distal side of the slot 22 to switch the expandable structure 30 to the second expansion state, the upper wrench 62 is limited by the distal side of the slide stop 63 at the slot 22, so that the expandable structure 30 remains in the second expansion state; as Figure 1 and Figure 3As shown, when the upper wrench 62 reaches the middle and far section of the hollowed-out slot 22, which is approximately flush with the notch 631 of the slide block 63, and the expandable structure 30 is switched to the retracted state, the upper wrench 62 is slid into the notch 631 by sliding it to the hollowed-out slot 22, thereby limiting the upper wrench 62 and keeping the expandable structure 30 in the retracted state. In this way, the slide block 63 can be used to maintain the switched state of the expandable structure 30, thus preventing the operator from accidentally touching the upper wrench 62 and causing the expandable structure 30 to switch states. Preferably, the outer tube 20 on one side of the circumferential direction of the hollowed-out slot 22 has engraved scale lines and text prompts to indicate the positions of the upper wrench 62 in the first expanded state, the retracted state, the second expanded state, and the slightly expanded state of the expandable structure 30, such as... Figure 3 As shown, for example, the scale line on the "Expand A" side indicates that when the upper wrench 62 reaches this scale line, the expandable structure 30 switches to the first expansion state; the scale line on the "Expand B" side indicates that when the upper wrench 62 reaches this scale line, the expandable structure 30 switches to the second expansion state; the scale line on the "Return" side indicates that when the upper wrench 62 reaches this scale line, the expandable structure 30 switches to the retracted state; and the scale line on the "Plug Removal" side indicates that when the upper wrench 62 reaches this scale line, the expandable structure 30 has undergone micro-expansion. This micro-expansion allows the sealing plug 71 of the sealing component 70 to retract into the tube hole of the conduit component 100, thus allowing the sealing plug 71 to be removed after the upper wrench 62 reaches this scale line.

[0055] Furthermore, although exemplary embodiments have been described in this invention, their scope includes any and all embodiments based on the invention that have equivalent elements, modifications, omissions, combinations (e.g., schemes involving intersections of various embodiments), adaptations, or alterations. Elements in the claims will be interpreted broadly based on the language used in the claims and are not limited to the examples described in this specification or during the implementation of this application, and such examples will be interpreted as non-exclusive. Therefore, this specification and examples are intended to be considered illustrative only, and the true scope and spirit are indicated by the full scope of the following claims and their equivalents.

[0056] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more of them) can be used in combination with each other. Other embodiments may be used by those skilled in the art upon reading the above description. Furthermore, in the above detailed description, various features may be grouped together to simplify the invention. This should not be construed as an intention that a disclosed feature, which is not claimed, is necessary for any claim. Rather, the subject matter of the invention may be less than all the features of the particular disclosed embodiment. Thus, the following claims are incorporated herein by reference as examples or embodiments, wherein each claim is independently considered as a separate embodiment, and these embodiments are contemplated as being possible in various combinations or arrangements. The scope of the invention should be determined by reference to the appended claims and the full scope of their equivalents.

[0057] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. An intracranial brain tissue retractor, comprising a positioning component for attachment to the edge of a bone window of the skull and a catheter component for establishing access for a treatment device through a through-hole in the positioning component into the ventricle and reaching the lesion, the catheter component comprising an inner tube and an outer tube allowing relative axial movement, the positioning component locking the catheter component through the outer tube, characterized in that, The distal end of the outer tube is configured with an expandable structure, which can be switched to a contracted state by means of elastic deformation and to a first expanded state by means of elastic reset. By driving the inner tube to move axially back and forth relative to the outer tube at the proximal end, the distal end of the inner tube is radially pulled inward to force the expandable structure to elastically deform and switch to the contracted state, and the expandable structure is released to allow the expandable structure to elastically reset and switch to the first expanded state. The expandable structure includes a plurality of main linear rods arranged circumferentially along the wall of the outer tube and extending axially. By configuring each main linear rod to be in a radially outward bending state in the reset state, the expandable structure is switched to the first expansion state by means of elastic reset. Each main linear rod has a meshing strip extending along its length on its radially inner side. The outer wall of the inner tube at its distal end has meshing grooves that mate with the meshing strips of each main linear rod. By driving the inner tube to move towards the distal end, the meshing strips slide into the meshing grooves, thereby pulling each main linear rod radially inward and forcing each main linear rod to elastically deform radially inward, so that the expandable structure switches from the first expanded state to the contracted state. By driving the inner tube to move towards the proximal end, the meshing strips are ejected from the meshing grooves, thereby releasing the pull on each main linear rod and allowing each main linear rod to elastically reset radially outward, so that the expandable structure switches from the contracted state to the first expanded state.

2. The intracranial brain tissue retractor according to claim 1, characterized in that, Each of the main linear rods has secondary linear rods arranged on both sides; the secondary linear rods are attached and fixed to the distal end of the main linear rods at their distal ends, and notches are provided on the secondary linear rods by removing material so that the secondary linear rods can be bent radially outward; the distal end of the inner tube has a plurality of protrusions with force-applying surfaces facing the proximal ends of each secondary linear rod, and by driving the inner tube, which has switched the expandable structure to the retracted state, to move it distally, the force-applying surfaces of each protrusion push against the proximal ends of each secondary linear rod to force each secondary linear rod to bend radially outward, thereby switching the expandable structure from the retracted state to the second expanded state.

3. The intracranial brain tissue retractor according to claim 2, characterized in that, A tongue with a free end is obtained by cutting on the wall of the inner tube at the distal end. The tongue is bent radially outward to obtain the protrusion that protrudes from the outer circumferential surface of the inner tube wall at the distal end. Thus, when the inner tube is driven to move towards the proximal end to switch the expandable structure from the contracted state to the first expanded state, the outer tube can force the protrusion to elastically deform radially inward and retract into the outer tube.

4. The intracranial brain tissue retractor according to claim 2, characterized in that, The main linear member includes a front straight segment on the distal side, a rear straight segment on the proximal side, and a curved segment between the front and rear straight segments; wherein: The secondary linear rods are located on both sides of the front straight segment of the primary linear rod.

5. The intracranial brain tissue retractor according to claim 2, characterized in that, The secondary linear rod has two expansion segments separated by three notches, and the two expansion segments form a triangular expansion configuration by bending and deforming radially outward; or The secondary linear rod has three expansion segments separated by four notches, and the three expansion segments form a trapezoidal expansion configuration by bending and deforming radially outward.

6. The intracranial brain tissue retractor according to claim 1, characterized in that, The intracranial brain tissue retractor also includes a occlusion component comprising a shaft and an occlusion plug attached to the distal end of the shaft. During the insertion of the catheter component into the ventricle, the shaft is located within the inner tube, and the occlusion plug is located at the distal end of the catheter component to seal the distal port of the expandable structure.

7. The intracranial brain tissue retractor according to claim 1, characterized in that, The radially outer side of the expandable structure is covered with an elastic membrane; wherein: The proximal end of the elastic membrane is attached to the proximal end of each main linear rod of the expandable structure, and the distal end of the elastic membrane is attached to the distal end of each main linear rod.

8. The intracranial brain tissue retractor according to claim 2, characterized in that, An axially extending perforated slot is formed on the wall of the outer tube at its proximal end. A lower wrench is fixed to the wall of the outer tube at the distal end of the perforated slot. An upper wrench is fixed to the wall of the inner tube opposite the perforated slot. The upper wrench is positioned opposite the lower wrench through the perforated slot. By holding the lower wrench and turning the upper wrench, the inner tube is driven to move relative to the outer tube. When the upper wrench moves to the proximal side of the perforated slot, the inner tube moves to a position that switches the expandable structure to a first expansion state. When the upper wrench moves to the distal side of the perforated slot, the inner tube moves to a position that switches the expandable structure to a second expansion state. A sliding stop that allows circumferential sliding is installed on the wall of the outer tube on one side of the circumferential direction of the hollowed-out slot, and a notch is opened on the side of the sliding stop in the circumferential direction; the wall of the outer tube on the other side of the circumferential direction of the hollowed-out slot is engraved with scale lines to indicate the position of the upper wrench in the first expanded state, the retracted state, and the second expanded state of the expandable structure, and the notch corresponds to the scale line indicating the retracted state; by pushing the sliding stop towards the hollowed-out slot, the sliding stop positions the upper wrench in its axial position.

9. The intracranial brain tissue retractor according to claim 7, characterized in that, Both ends of the main linear rod are provided with radially penetrating rivet holes. By injecting water-based colloid into the rivet holes and wetting or permeating the elastic membrane and then curing it, the colloid forms rivets that attach the elastic membrane to the main linear rod.

10. The intracranial brain tissue retractor according to claim 1 or 2, characterized in that, Each of the main linear rods is fitted with a silicone cap at its distal end.

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