Magnetic Resonance Imaging Navigation and Positioning Sheath and Assembly Method

Abstract

This invention provides a magnetic resonance imaging (MRI) navigation and positioning sheath and its assembly method, relating to the field of MRI navigation equipment technology. It includes an upper cavity, a lower cavity, and a central tube. The upper cavity contains a cylindrical cavity, which, when combined with the lower cavity, forms a spherical cavity. The cylindrical and spherical cavities are connected and filled with a developing solution. The central tube is positioned within the combined structure of the upper and lower cavities and passes through both the cylindrical and spherical cavities. This separate, nested structure design improves the ease of manufacturing the MRI navigation and positioning sheath, enables convenient sealed filling of the MRI developing solution, and provides a high-precision structural profile, resulting in excellent imaging and positioning performance and improved accuracy in needle positioning.

Description

Technical Field

[0001] This invention relates to the field of magnetic resonance navigation equipment technology, specifically to a magnetic resonance imaging navigation and positioning sheath and its assembly method. Background Technology

[0002] When magnetic resonance-compatible robots operate in a magnetic resonance environment, a magnetic resonance navigation system is often required to determine the position and orientation of the robot's end effector. By employing a positioning method based on magnetic resonance imaging, the relative relationship between the robot's end effector's operating coordinate system and the magnetic resonance image coordinate system can be established, thereby obtaining accurate robot navigation parameters.

[0003] Localization in magnetic resonance imaging requires the use of landmarks with precise geometric features, such as standard structures like cylinders and spheres. For neurosurgical interventions, precise positioning of the puncture needle is crucial to ensure it reaches a specific location and orientation.

[0004] A Chinese patent application with publication number CN210204905U discloses a nuclear magnetic resonance positioning and navigation puncture needle, which includes a needle body for puncture. The needle body is characterized by having a water column distributed along the axial direction inside the needle body, and a cavity arranged in the axial direction inside the needle body; water is disposed in the cavity; the cavity extends from the tip of the needle body to the tail end of the needle body and the two ends of the cavity are closed.

[0005] The existing nuclear magnetic resonance positioning and navigation device is directly integrated on the puncture needle, which requires adjusting its position during the puncture process. This is inconvenient to operate and has poor positioning effect, and there are areas for improvement. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a magnetic resonance imaging navigation and positioning sheath and its assembly method.

[0007] According to the present invention, a magnetic resonance imaging navigation and positioning sheath includes an upper cavity, a lower cavity, and a central tube. A cylindrical cavity is provided in the upper cavity, and the upper cavity and the lower cavity cooperate to form a spherical cavity. The cylindrical cavity and the spherical cavity are connected and filled with a developing solution. The central tube is disposed in the assembly formed by the upper cavity and the lower cavity, and the central tube passes through the cylindrical cavity and the spherical cavity.

[0008] Preferably, the upper cavity, lower cavity, cylindrical cavity, spherical cavity, and central tube are all coaxially arranged.

[0009] Preferably, the upper cavity and the lower cavity are bonded together by a concave-convex fit.

[0010] Preferably, the cylindrical cavity and the spherical cavity are connected by a connecting channel disposed in the upper cavity.

[0011] Preferably, the upper cavity is connected to an upper end cap at the end away from the lower cavity, and the upper end cap closes the cylindrical cavity.

[0012] Preferably, one end of the central tube is sealed and bonded to the end of the lower cavity away from the upper cavity, and the other end of the central tube is sealed and bonded to the upper end cap.

[0013] Preferably, the diameter of the upper cavity is 0.8 mm to 12 mm; the diameter of the lower cavity is 0.8 mm to 12 mm; the diameter of the cylindrical cavity is greater than 0.6 mm, and the diameter of the cylindrical cavity is smaller than the diameter of the upper cavity.

[0014] Preferably, the inner diameter of the central tube allows the puncture needle to pass through.

[0015] The assembly method of a magnetic resonance imaging navigation and positioning sheath according to the present invention includes the following steps:

[0016] Step S1: Prepare the upper cavity, lower cavity, upper end cap, and central shaft tube;

[0017] Step S2: Bond the upper cavity and the lower cavity together;

[0018] Step S3: Insert the central shaft tube into the assembly formed by bonding the upper cavity and the lower cavity, and connect the central shaft tube to the lower cavity;

[0019] Step S4: Pour developing solution into the cylindrical cavity and the spherical cavity;

[0020] Step S5: After the developing solution is filled, install the upper end cap into the upper cavity and bond the upper end cap to the central tube.

[0021] Preferably, step S4 includes the following sub-steps:

[0022] Step S4.1: Pour developing solution into the cylindrical cavity from the end of the upper cavity away from the lower cavity;

[0023] Step S4.2: Centrifuge the developing solution in the cylindrical cavity into the spherical cavity.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. This invention, through the adoption of a separate nested structure design, helps to improve the ease of manufacturing magnetic resonance navigation and positioning sheaths, realizes convenient sealing and filling of magnetic resonance imaging solutions, and has a high-precision structural profile, with good imaging and positioning performance, which helps to improve the accuracy of puncture needle positioning.

[0026] 2. The present invention connects the cylindrical cavity and the spherical cavity through the connecting channel, which helps to improve the convenience of magnetic resonance imaging solution perfusion.

[0027] 3. By setting an uneven structure between the upper cavity and the lower cavity, the present invention can prevent the adhesive between the upper cavity and the lower cavity from leaking into the internal spherical cavity and affecting the imaging effect of the positioning target ball. Attached Figure Description

[0028] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0029] Figure 1 This is a cross-sectional view that mainly illustrates the overall structure of the positioning sheath in this invention;

[0030] Figure 2 This is an axonometric schematic diagram illustrating the overall structure of the positioning sheath of the present invention;

[0031] Figure 3 This is a diagram illustrating the imaging effect of the positioning sheath in a magnetic resonance image, which is the main feature of this invention.

[0032] As shown in the figure: 101, upper cavity; 102, lower cavity; 103, upper end cover; 104, central shaft tube; 105, connecting channel; 106, spherical cavity; 107, cylindrical cavity. Detailed Implementation

[0033] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0034] like Figure 1 and Figure 2 As shown, a magnetic resonance imaging (MRI) navigation and positioning sheath according to the present invention includes an upper cavity 101, a lower cavity 102, and a central tube 104. A cylindrical cavity 107 is disposed within the upper cavity 101. The upper cavity 101 and the lower cavity 102 cooperate to form a spherical cavity 106. The cylindrical cavity 107 and the spherical cavity 106 are connected and filled with a contrast agent. The central tube 104 is disposed within the assembly formed by the upper cavity 101 and the lower cavity 102, and passes through the cylindrical cavity 107 and the spherical cavity 106. The inner diameter of the central tube 104 allows a puncture needle to pass through.

[0035] The cylindrical cavity 107 inside the upper cavity 101 is used for directional positioning of the sheath, and the spherical cavity 106 formed by the upper cavity 101 and the lower cavity 102 is used for position positioning of the tip of the sheath.

[0036] Specifically, the upper cavity 101, lower cavity 102, cylindrical cavity 107, spherical cavity 106, and central tube 104 are all coaxially arranged. The design of the central tube 104 ensures that the surgical puncture needle and sheath remain coaxial at all times.

[0037] To facilitate surgical procedures, the overall sheath outer diameter is typically designed to be less than or equal to 12 mm. Within this size, due to resolution limitations of MRI equipment, the overall sheath outer diameter is typically designed to be greater than or equal to 0.8 mm. To achieve MRI-guided navigation, a cylinder with a diameter of at least 6 mm needs to be placed inside the sheath to achieve clearer spatial structural imaging and accurate centerline extraction. This requires designing the upper cavity 101 to have a diameter of 0.8 mm to 12 mm, the lower cavity 102 to have a diameter of 0.8 mm to 12 mm, and the cylindrical cavity 107 to have a diameter greater than 0.6 mm, but smaller than the diameter of the upper cavity 101. These design limitations result in a thinner sheath wall, placing higher demands on the structural assembly design.

[0038] This application provides coaxially arranged hemispherical cavities 106 at the ends of the upper cavity 101 near the lower cavity 102 and at the ends of the lower cavity 102 near the upper cavity 101. These cavities are connected to the upper and lower cavities 102, resulting in a spherical cavity 106 at the sheath tip. It should be noted that a cylindrical cavity 107 is coaxially arranged within the upper cavity 101, with the end of the cylindrical cavity 107 away from the lower cavity 102 being open, thus enabling the filling of the developing liquid. A connecting channel 105 is also provided within the upper cavity 101, connecting the cylindrical cavity 107 and the hemispherical cavity 106 within the upper cavity 101.

[0039] The upper cavity 101 and the lower cavity 102 are bonded together by a concave-convex fit. Specifically, the connection between the upper cavity 101 and the lower cavity 102 is bonded together by a concave-convex fit. This concave-convex fit structure can be a groove and protrusion fit as in the prior art, which can prevent the adhesive between the upper cavity 101 and the lower cavity 102 from leaking into the internal spherical cavity 106 and affecting the imaging effect of the positioning target ball.

[0040] The upper cavity 101 is connected to an upper end cap 103 at the end away from the lower cavity 102, and the upper end cap 103 closes the cylindrical cavity 107. One end of the central shaft tube 104 is sealed and bonded to the end of the lower cavity 102 away from the upper cavity 101, and the other end of the central shaft tube 104 is sealed and bonded to the upper end cap 103.

[0041] The present invention also provides a method for assembling a magnetic resonance imaging navigation and positioning sheath, comprising the following steps:

[0042] Step S1: Prepare the upper cavity 101, lower cavity 102, upper end cap 103, and central shaft tube 104.

[0043] Step S2: Bond the upper cavity 101 and the lower cavity 102 together.

[0044] Step S3: Insert the central shaft tube 104 into the assembly formed by bonding the upper cavity 101 and the lower cavity 102, and connect the central shaft tube 104 to the lower cavity 102.

[0045] Step S4: Inject developing solution into the cylindrical cavity 107 and the spherical cavity 106. Specifically, this includes:

[0046] Step S4.1: Pour developing solution into the cylindrical cavity from the end of the upper cavity 101 away from the lower cavity 102.

[0047] Step S4.2: Centrifuge the developing solution in the cylindrical cavity 107 into the spherical cavity 106.

[0048] Step S5: After the developing solution is filled, install the upper end cap 103 into the upper cavity 101 and bond and fix the upper end cap 103 to the central shaft tube 104.

[0049] To further explain, the assembly process of the sheath is as follows: First, the upper cavity 101 and the lower cavity 102 are bonded together using a tongue-and-groove joint. Medical-grade adhesive or ultrasonic welding technology can be used to weld the polymer joint. A thin central tube 104 passes through the middle, with its outer diameter matching the inner diameter of both the upper cavity 101 and the lower cavity 102. The head end of the central tube 104 is then bonded to the head end of the lower cavity. After ensuring a good seal, the sheath is assembled from the end of the upper cavity 101 furthest from the lower cavity 102 towards the cylindrical... The cavity is filled with the prepared magnetic resonance imaging solution, and the solution in the upper cavity is centrifuged into the spherical cavity 106 in the lower cavity. The positioning of the spherical cavity 106 needs to ensure that the solution is fully filled. The cylindrical cavity 107 of the upper cavity 101 is used for orientation positioning and can leave a certain amount of air in the upper part to facilitate the next step of assembly. After the solution filling and centrifugation are completed, the middle hole of the upper end cover 103 is aligned and sealed with the central shaft tube 104, and its two ends are glued to the upper part of the upper cavity 101, thus completing the overall positioning and assembly.

[0050] The imaging effect of this invention under magnetic resonance is as follows: Figure 3As shown, the positioning direction of the sheath can be accurately calculated by forming an image of the upper cylinder. The position of the sheath tip can be accurately obtained by positioning the center point of the lower sphere. After the puncture needle passes through the middle of the sheath, the distance between the center point of the sphere and the top of the upper end cap 103 can be obtained according to the designed dimensions. Therefore, by simply placing the depth limiter of the puncture needle on the top of the upper end cap 103, the accurate positioning of the puncture needle tip can be achieved.

[0051] Despite the limitations of small size, this invention employs a separate nested structure design to achieve portable manufacturing of the magnetic resonance navigation and positioning sheath. This enables convenient sealed filling of the magnetic resonance imaging solution, and provides a high-precision structural profile with excellent imaging and positioning performance. Compared to other positioning methods, such as camera positioning, this invention avoids registration errors between different modal image data, achieving higher precision in puncture needle positioning.

[0052] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0053] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A magnetic resonance imaging navigated positioning sheath, characterized in that, The application relates to a magnetic resonance imaging navigation positioning sheath, which comprises an upper cavity (101), a lower cavity (102) and a middle shaft pipe (104), the upper cavity (101) is internally provided with a cylindrical cavity (107), the upper cavity (101) cooperates with the lower cavity (102) to form a spherical cavity (106), the cylindrical cavity (107) and the spherical cavity (106) are communicated, and the cylindrical cavity (107) and the spherical cavity (106) are filled with a developing solution. The middle shaft pipe (104) is arranged in the combination formed by the upper cavity (101) and the lower cavity (102), and the middle shaft pipe (104) penetrates through the cylindrical cavity (107) and the spherical cavity (106).

2. The magnetic resonance imaging navigated positioning sheath of claim 1, wherein, The upper cavity (101), the lower cavity (102), the cylindrical cavity (107), the spherical cavity (106) and the middle shaft pipe (104) are coaxially arranged.

3. The magnetic resonance imaging navigated positioning sheath of claim 1, wherein, The upper cavity (101) and the lower cavity (102) are bonded through concave-convex cooperation.

4. The magnetic resonance imaging navigated positioning sheath of claim 1, wherein, The cylindrical cavity (107) and the spherical cavity (106) are communicated through a connecting channel (105) arranged in the upper cavity (101).

5. The magnetic resonance imaging navigated positioning sheath of claim 1, wherein, The upper end cover (103) is connected to one end of the upper cavity (101) away from the lower cavity (102), and the upper end cover (103) seals the cylindrical cavity (107).

6. The magnetic resonance imaging navigated positioning sheath of claim 5, wherein, One end of the middle shaft pipe (104) is sealingly bonded to the end of the lower cavity (102) away from the upper cavity (101), and the other end of the middle shaft pipe (104) is sealingly bonded to the upper end cover (103).

7. The magnetic resonance imaging navigated positioning sheath of claim 1, wherein, The diameter of the upper cavity (101) is 0.8mm to 12mm. The diameter of the lower cavity (102) is 0.8mm to 12mm. The diameter of the cylindrical cavity (107) is greater than 0.6mm, and the diameter of the cylindrical cavity (107) is smaller than the diameter of the upper cavity (101).

8. The magnetic resonance imaging navigated positioning sheath of claim 1, wherein, The inner diameter of the middle shaft pipe (104) allows a puncture needle to pass through.

9. An assembly method for magnetic resonance imaging navigated positioning of a sheath, characterized in that, The magnetic resonance imaging navigation positioning sheath is prepared by the steps of: Step S1, preparing the upper cavity (101), the lower cavity (102), the upper end cover (103) and the middle shaft pipe (104); Step S2, bonding the upper cavity (101) and the lower cavity (102) together; Step S3, penetrating the middle shaft pipe (104) into the combination formed by the upper cavity (101) and the lower cavity (102) bonded together, and connecting the middle shaft pipe (104) with the lower cavity (102); Step S4, injecting the developing solution into the cylindrical cavity (107) and the spherical cavity (106); Step S5, after the developing solution is injected, the upper end cover (103) is installed to the upper cavity (101), and the upper end cover (103) is bonded and fixed with the middle shaft pipe (104).

10. The method of assembling a magnetic resonance imaging navigated positioning sheath of claim 9, wherein, Step S4 comprises the following substeps: Step S4.1, injecting the developing solution into the cylindrical cavity from one end of the upper cavity (101) away from the lower cavity (102); Step S4.2, using a centrifugal measure to centrifuge the developing solution in the cylindrical cavity (107) into the spherical cavity (106).

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