Capsule tension ring

Abstract

The present invention relates to a capsular tension ring that is easy to safely implant, and the capsular tension ring has a smooth transition portion between a main body and a positioning portion. When viewed from a direction perpendicular to the plane where the capsular tension ring is located, the curvature radius of the inner contour line of the transition portion is 0.8 mm to 5.0 mm. The capsular tension ring of the present invention can avoid stress concentration during implantation, thereby reducing the risk of fracture.

Description

Technical Field

[0001] The invention relates to a capsular tension ring. The capsular tension ring according to the invention can avoid stress concentration during implantation and reduce the risk of fracture. Background Art

[0002] The capsular bag tension ring is a compressible and deformable roughly annular member with an opening. Before being implanted in the capsular bag, the capsular bag tension ring is compressed and the outer diameter is reduced, so that the capsular bag tension ring has a tendency to expand outward. After being implanted in the capsular bag, the capsular bag tension ring expands outward, propping the wrinkled capsular bag into a circle. After being implanted in the capsular bag, the capsular bag tension ring is close to the capsular bag membrane, which can maintain the tension of the capsular bag, prevent the posterior capsule membrane from wrinkling, resist the contraction of the capsular bag, and maintain the integrity of the capsular bag. The capsular bag tension ring includes a roughly annular main body and a positioning part located at the two ends of the main body, and the positioning part has a positioning hole. The cross-section of the main body of the existing capsular bag tension ring is mostly circular, elliptical, rectangular or polygonal. The capsular bag tension ring is implanted in the capsular bag through an implanter, and is used to treat congenital lens subluxation, preoperative or intraoperative suspensory ligament rupture, suspensory ligament fragility, and the risk of capsular bag shrinkage, especially patients with high myopia.

[0003] The implantation of the capsular tension ring and the implantation of the intraocular lens are often performed simultaneously. The capsular tension ring with a rectangular or polygonal cross-section can inhibit and prevent the proliferation and migration of lens epithelial cells. Posterior capsule opacity is caused by the proliferation and migration of residual lens epithelial cells after cataract surgery to the posterior surface of the intraocular lens and the posterior capsule. Therefore, the implantation of a capsular tension ring with a rectangular or polygonal cross-section can prevent the occurrence of posterior capsule opacity.

[0004] Existing capsular bag tension rings are usually made of PMMA material with a certain degree of brittleness. Since the radius of curvature at the transition between the main body and the positioning part is small, fractures often occur between the positioning part and the main body when implanted with an implanter. If the fracture occurs when the capsular bag tension ring is loaded, the fragments of the broken capsular bag tension ring are outside the eye, and you can choose to directly replace it with a new capsular bag tension ring. If the fracture occurs during the implantation process in the eye, the fragments of the broken capsular bag tension ring will be scattered in the eye tissue, and the scattered fragments need to be cleaned out, which is a tedious and necessary task for the doctor. Once the fragments are left in the eye, they will cause damage to the eye tissue. Therefore, the last thing the doctor wants to happen is that the capsular bag tension ring breaks during the implantation process.

[0005] Existing implanters for implanting capsular tension rings are as follows Figure 1 As shown, a slightly curved, elongated guide tube can be seen on the left.

[0006] To facilitate implantation through a tiny incision, the smaller the inner and outer diameters of the guide tube of the implanter, the better. The smaller the diameter of the guide tube, the smaller the incision required for implanting the tension ring, the less trauma caused to the patient, and the more conducive to postoperative recovery and reduced complications. The inner diameter of the guide tube of the existing implanter is 1.1-1.3 mm, and the outer diameter is 1.6-1.8 mm.

[0007] When implanting the capsular bag tension ring, you need to load (pull) the capsular bag tension ring into the implanter first. First, by pressing the rear end of the implanter push rod, push the push pin out of the implanter guide tube, let the hook at the front end of the push pin hook one of the positioning holes of the capsular bag tension ring, then release the implanter push rod, let the capsular bag tension ring slowly pull into the implanter guide tube, and the shape of the capsular bag tension ring will deform to adapt to the shape of the implanter guide tube. During surgical implantation, the capsular bag tension ring that has been loaded into the implanter guide tube is pushed out by pressing the implanter push rod, and the capsular bag tension ring is implanted into the intraocular capsular bag through the corneal incision, and it is ensured that the capsular bag tension ring can be unfolded in a clockwise direction in the capsular bag. After the capsular bag tension ring is implanted in the correct position, the capsular bag tension ring is released through the capsular bag tension ring positioning hole. After the capsular bag tension ring is completely released, carefully remove the implanter to complete the implantation of the capsular bag tension ring.

[0008] The positioning parts at both ends of the roughly annular main body of the capsular bag tension ring are provided with positioning holes, which facilitate the insertion of the steel wire of the implanter into the positioning holes to hook the capsular bag tension ring during surgery and then implant it into the capsular bag. The transition between the positioning part and the main body of the existing capsular bag tension ring is very narrow, and the curvature radius is very small, such as Figure 2 As shown in the figure. When the tension ring of the capsular bag is pulled and loaded into the implanter, since the inner diameter of the implanter guide tube is very small and made of rigid metal, the tension ring will inevitably contact the implanter guide tube and generate a force. If the force is large, it is easy to break between the main body and the positioning part of the tension ring. In addition, the same problem may also occur in the process of pushing the tension ring out of the implanter. Summary of the invention

[0009] The present invention provides a bladder tension ring, which includes: a roughly annular main body, the main body having a first end and a second end; a roughly circular first positioning part, the first positioning part having a first positioning hole; a roughly circular second positioning part, the second positioning part having a second positioning hole; a first transition part, the first transition part forms a smooth transition between the first positioning part and the first end; a second transition part, the second transition part forms a smooth transition between the second positioning part and the second end; a notch, the notch is located between the first positioning part and the second positioning part; wherein the outer diameter of the first positioning part and the second positioning part is larger than the cross-sectional size of the main body, and wherein, viewed from a direction perpendicular to the plane where the bladder tension ring is located, the radius of curvature of the inner contour line of the first transition part and / or the second transition part is 0.8 mm to 5.0 mm, preferably 2.0 mm to 3.0 mm, and more preferably 2.0 mm to 2.5 mm.

[0010] In one embodiment, the diameter of the body is 11 mm to 15 mm, preferably 12 mm to 14 mm, more preferably 12 mm to 13 mm.

[0011] In one embodiment, the cross-section of the body is circular, rectangular or polygonal.

[0012] In one embodiment, the cross section of the body is circular with a diameter of 0.18 mm to 0.25 mm, preferably 0.20 mm to 0.24 mm, more preferably 0.21 mm to 0.23 mm.

[0013] In one embodiment, the width of the notch is 4 mm to 8 mm, preferably 6 mm to 8 mm, and more preferably 6 mm to 7 mm.

[0014] In one embodiment, the outer diameters of the first positioning portion and the second positioning portion are 0.60 mm to 0.85 mm, preferably 0.65 mm to 0.75 mm, and more preferably 0.65 mm to 0.70 mm.

[0015] In one embodiment, the bladder tension ring is made of a material with a Poisson's ratio of 0.2 to 0.4, preferably a material with a Poisson's ratio of 0.25 to 0.35, and more preferably a material with a Poisson's ratio of 0.30 to 0.32.

[0016] In one embodiment, the bladder tension ring is made of a material with a Young's modulus of 1 GPa to 30 GPa, preferably made of a material with a Young's modulus of 2 GPa to 20 GPa, more preferably made of a material with a Young's modulus of 3 GPa to 10 GPa, and more preferably made of a material with a Young's modulus of 3 GPa to 5 GPa.

[0017] In one embodiment, viewed from a direction perpendicular to the plane where the bladder tension ring is located, an inner contour line of the first transition portion and / or the second transition portion is an arc or a parabola. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram shows an existing implanter for implanting a capsular tension ring;

[0019] Figure 2 An existing bladder tension ring is schematically shown;

[0020] Figure 3 Schematically showing a plan view of a bladder tension ring according to the present invention;

[0021] Figure 4 schematically shows a transmission view of a bladder tension ring according to the present invention;

[0022] Figure 5a-5j Schematically showing a partial schematic diagram of a bladder tension ring with different curvature radii according to the present invention;

[0023] Figure 6a-6g shows a curve showing the variation of the deformation amount of the bladder tension ring with the curvature radius according to the present invention for different Young's moduli; and

[0024] Figure 7a-7e The graph shows the variation curve of the deformation amount of the bladder tension ring according to the present invention with the curvature radius for different Poisson's ratios. DETAILED DESCRIPTION

[0025] The present invention provides a capsular tension ring that is easy to safely implant, and a smooth transition portion is provided between the main body and the positioning portion of the capsular tension ring. The capsular tension ring of the present invention can not only maintain the integrity of the capsular bag, but also play a barrier role and a contact inhibition role, thereby preventing the proliferation and migration of lens epithelial cells and preventing the occurrence of anterior capsule opacification and posterior capsule opacification.

[0026] The transition between the main body and the positioning part of the capsular tension ring of the present invention is smoother, and a smooth transition curve is provided from the positioning part to the main body. When the capsular tension ring is installed in the implanter, the capsular tension ring is subjected to a more uniform and dispersed force, thus avoiding stress concentration and reducing the risk of fracture.

[0027] Figure 3 A plan view of a bladder tension ring according to the present invention is schematically shown. Figure 3 As shown, the bladder tension ring 100 according to the present invention includes a generally annular main body 110. The main body 110 has a first end 114 and a second end 116. In some embodiments, the diameter D of the main body 110 can be 11 mm to 15 mm, preferably 12 mm to 14 mm, and more preferably 12 mm to 13 mm. In some embodiments, the cross-section of the main body 110 can be circular, rectangular, or polygonal. In some embodiments, for the main body 110 with a circular cross-section, the diameter of the cross-section can be 0.18 mm to 0.25 mm, preferably 0.20 mm to 0.24 mm, and more preferably 0.21 mm to 0.23 mm. The bladder tension ring 100 according to the present invention also includes a generally circular first positioning portion 120 and a generally circular second positioning portion 130. The first positioning portion 120 has a first positioning hole 122, and the second positioning portion 130 has a second positioning hole 132. The bladder tension ring 100 according to the present invention also includes a first transition portion 140 and a second transition portion 150. The first transition portion 140 forms a smooth transition between the first positioning portion 120 and the first end 114 of the body 110, and the second transition portion 150 forms a smooth transition between the second positioning portion 130 and the second end 116 of the body 110. The outer diameter of the first positioning portion 120 and the second positioning portion 130 is greater than the cross-sectional dimension of the body 110. In some embodiments, as Figure 3As shown, the outer diameters of the first positioning portion 120 and the second positioning portion 130 may be the same. Of course, the outer diameters of the first positioning portion 120 and the second positioning portion 130 may also be different. The mechanical strength of the positioning portions 120, 130 is related to the outer diameters of the positioning portions 120, 130 and the inner diameters of the positioning holes 122, 132. On the one hand, the radial width of the positioning portions 120, 130 (i.e., half of the difference between the outer diameter of the positioning portions 120, 130 and the inner diameter of the positioning holes 122, 132) cannot be too small, otherwise the mechanical strength of the positioning portions 120, 130 is insufficient. For example, the radial width of the positioning portions 120, 130 should be above 0.15 mm. On the other hand, the inner diameters of the positioning holes 122, 132 cannot be too small. If the inner diameters of the positioning holes 122, 132 are too small, loading is very difficult, and the steel wire used for the hook of the implanter is required to be very thin, which increases the difficulty of processing. For example, the inner diameter of the positioning holes 122 and 132 should be above 0.3 mm. In some embodiments, the outer diameter d of the first positioning portion 120 and the second positioning portion 130 can be 0.60 mm to 0.85 mm, preferably 0.65 mm to 0.75 mm, and more preferably 0.65 mm to 0.70 mm. The pouch tension ring 100 according to the present invention also includes a notch 112. The notch 112 is located between the first positioning portion 120 and the second positioning portion 130. The size of the notch will affect the degree of compression of the pouch tension ring and the force of outward expansion after compression. A notch that is too small is not conducive to the compression of the pouch tension ring, nor is it conducive to outward expansion after compression. In some embodiments, the width W of the notch 112 can be 4 mm to 8 mm, preferably 6 mm to 8 mm, and more preferably 6 mm to 7 mm. Figure 3 As shown, from the direction perpendicular to the plane where the bladder tension ring 100 is located, the inner contour line of the first transition portion 140 and / or the second transition portion 150 can be an arc. Of course, from the direction perpendicular to the plane where the bladder tension ring 100 is located, the inner contour line of the first transition portion 140 and / or the second transition portion 150 can also be other shapes, such as a parabola. In this article, the "inner contour line" refers to the contour line located on the inside (that is, the side closer to the center of the approximately annular body 110 of the bladder tension ring 100). As shown in FIG. Figure 3 As shown, viewed from a direction perpendicular to the plane where the bladder tension ring 100 is located, the inner contour lines of the first transition portion 140 and the second transition portion 150 have the same radius of curvature R. Of course, viewed from a direction perpendicular to the plane where the bladder tension ring 100 is located, the radius of curvature of the inner contour lines of the first transition portion 140 and the second transition portion 150 may also be different.

[0028] Figure 4 A perspective view of a bladder tension ring according to the present invention is schematically shown.

[0029] The force analysis and simulation results of the bladder tension ring according to the present invention are given below.

[0030] Currently, PMMA (polymethyl methacrylate) is used as the material for capsular tension rings in clinical practice, with a density of approximately 1.18 g / cm 3 , Poisson's ratio μ is about 0.32. For PMMA, Young's modulus E will be different for different processing methods. The Young's modulus E of PMMA can be 3 GPa to 30 GPa.

[0031] The Poisson's ratio of a material is certain, and different Poisson's ratios represent different materials. In some embodiments of the present invention, the bladder tension ring 100 is made of a material with a Poisson's ratio of 0.2 to 0.4, preferably made of a material with a Poisson's ratio of 0.25 to 0.35, and more preferably made of a material with a Poisson's ratio of 0.30 to 0.32.

[0032] In addition, for different materials, the Young's modulus E will also be different. In some embodiments of the present invention, the bladder tension ring 100 is made of a material with a Young's modulus of 1 GPa to 30 GPa, preferably made of a material with a Young's modulus of 2 GPa to 20 GPa, more preferably made of a material with a Young's modulus of 3 GPa to 10 GPa, and more preferably made of a material with a Young's modulus of 3 GPa to 5 GPa.

[0033] Figure 5a-5j A partial schematic diagram of a bladder tension ring with different curvature radii R according to the present invention is schematically shown.

[0034] Force simulation was performed for different curvature radii R. When the bag tension ring was loaded or pushed out, all cases were assumed to be subjected to a force of 1N. Then, on this basis, simulations were performed for different curvature radii to find the point where the force caused the maximum deformation. From the simulation results, no matter how R was taken, the point where the force was the largest (the first place where the fracture occurred) was close to the positioning part.

[0035] The Young's modulus E is set to 1 GPa and the Poisson's ratio μ is set to 0.32. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 6a The graph shown.

[0036] The Young's modulus E is set to 2 GPa and the Poisson's ratio μ is set to 0.32. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 6b The graph shown.

[0037] The Young's modulus E is set to 3 GPa and the Poisson's ratio μ is set to 0.32. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 6cThe graph shown.

[0038] The Young's modulus E is set to 5 GPa and the Poisson's ratio μ is set to 0.32. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 6d The graph shown.

[0039] The Young's modulus E is set to 10 GPa and the Poisson's ratio μ is set to 0.32. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 6e The graph shown.

[0040] The Young's modulus E is set to 20 GPa and the Poisson's ratio μ is set to 0.32. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 6f The graph shown.

[0041] The Young's modulus E is set to 30 GPa and the Poisson's ratio μ is set to 0.32. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 6g The graph shown.

[0042] Figure 6a-6g They all show a similar trend of change, that is, the deformation first decreases with the increase of the curvature radius, the deformation is the smallest when the curvature radius is 2 mm to 2.5 mm, and then slowly increases with the increase of the curvature radius.

[0043] The Poisson's ratio μ is set to 0.20 and the Young's modulus E is set to 3 GPa. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 7a The graph shown.

[0044] The Poisson's ratio μ is set to 0.25 and the Young's modulus E is set to 3 GPa. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 7b The graph shown.

[0045] The Poisson's ratio μ is set to 0.30 and the Young's modulus E is set to 3 GPa. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 7c The graph shown.

[0046] The Poisson's ratio μ is set to 0.35 and the Young's modulus E is set to 3 GPa. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 7d The graph shown.

[0047] The Poisson's ratio μ is set to 0.40 and the Young's modulus E is set to 3 GPa. The deformation at different curvature radii R is simulated and the following results are obtained: Figure 7e The graph shown.

[0048] Figure 7a-7eThey all show a similar trend of change, that is, the deformation first decreases with the increase of the curvature radius, the deformation is the smallest when the curvature radius is 2 mm to 2.5 mm, and then slowly increases with the increase of the curvature radius.

[0049] according to Figure 6a-6g as well as Figure 7a-7e It can be seen that, advantageously, the radius of curvature R of the inner contour line of the first transition portion 140 and / or the second transition portion 150, viewed from a direction perpendicular to the plane where the bladder tension ring 100 is located, can be 0.8 mm to 5.0 mm, preferably 2.0 mm to 3.0 mm, and more preferably 2.0 mm to 2.5 mm.

[0050] Although the present invention has been described with reference to (one or more) exemplary embodiments, it will be understood by those skilled in the art that the present invention is not limited to the exact structure and components described herein, and that various modifications, changes and variations may be apparent from the foregoing description without departing from the spirit and scope of the present invention as defined in the appended claims. The present invention is not limited by the illustrated order of steps, as some steps may be performed in a different order and / or simultaneously with other steps. Therefore, the present invention is not limited to the specific (one or more) embodiments disclosed, but will include all embodiments falling within the scope of the appended claims.

Claims

1. A bladder tension ring (100), the bladder tension ring (100) comprising: A generally annular body (110) having a first end (114) and a second end (116); A substantially circular first positioning portion (120), wherein the first positioning portion (120) has a first positioning hole (122); A substantially circular second positioning portion (130), wherein the second positioning portion (130) has a second positioning hole (132); A first transition portion (140), the first transition portion (140) forming a smooth transition between the first positioning portion (120) and the first end portion (114); a second transition portion (150), wherein the second transition portion (150) forms a smooth transition between the second positioning portion (130) and the second end portion (116); a notch (112), wherein the notch (112) is located between the first positioning portion (120) and the second positioning portion (130); The outer diameters of the first positioning portion (120) and the second positioning portion (130) are larger than the cross-sectional dimensions of the main body (110), and Wherein, viewed from a direction perpendicular to the plane where the bladder tension ring (100) is located, the radius of curvature of the inner contour line of the first transition portion (140) and / or the second transition portion (150) is 0.8 mm to 5.0 mm.

2. The bladder tension ring (100) according to claim 1, wherein: The curvature radius of the inner contour line of the first transition portion (140) and / or the second transition portion (150) is 2.0 mm to 3.0 mm.

3. The bladder tension ring (100) according to claim 1, wherein: The radius of curvature of the inner contour line of the first transition portion (140) and / or the second transition portion (150) is 2.0 mm to 2.5 mm.

4. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The diameter (D) of the body (110) is 11 mm to 15 mm.

5. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The diameter (D) of the body (110) is 12 mm to 14 mm.

6. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The diameter (D) of the body (110) is 12 mm to 13 mm.

7. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The cross section of the body (110) is circular or polygonal.

8. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The cross section of the body (110) is rectangular.

9. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The cross section of the body (110) is circular, and its diameter is 0.18 mm to 0.25 mm.

10. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The cross section of the body (110) is circular, and its diameter is 0.20 mm to 0.24 mm.

11. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The cross section of the body (110) is circular, and its diameter is 0.21 mm to 0.23 mm.

12. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The width of the notch (112) is 4 mm to 8 mm.

13. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The width of the notch (112) is 6 mm to 8 mm.

14. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The width of the notch (112) is 6 mm to 7 mm.

15. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The outer diameter (d) of the first positioning portion (120) and the second positioning portion (130) is 0.60 mm to 0.85 mm.

16. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The outer diameter (d) of the first positioning portion (120) and the second positioning portion (130) is 0.65 mm to 0.75 mm.

17. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The outer diameter (d) of the first positioning portion (120) and the second positioning portion (130) is 0.65 mm to 0.70 mm.

18. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The bladder tension ring (100) is made of a material with a Poisson's ratio of 0.2 to 0.

4.

19. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The bladder tension ring (100) is made of a material with a Poisson's ratio of 0.25 to 0.

35.

20. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The bladder tension ring (100) is made of a material with a Poisson's ratio of 0.30 to 0.

32.

21. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The bladder tension ring (100) is made of a material with a Young's modulus of 1 GPa to 30 GPa.

22. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The bladder tension ring (100) is made of a material with a Young's modulus of 2 GPa to 20 GPa.

23. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The bladder tension ring (100) is made of a material with a Young's modulus of 3 GPa to 10 GPa.

24. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: The bladder tension ring (100) is made of a material with a Young's modulus of 3 GPa to 5 GPa.

25. The bladder tension ring (100) according to any one of claims 1 to 3, wherein: Viewed from a direction perpendicular to the plane where the bladder tension ring (100) is located, the inner contour line of the first transition portion (140) and / or the second transition portion (150) is an arc or a parabola.

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