CN112826563A - Medical implant and method of making the same - Google Patents

Referring to fig. 1-2 and fig. 3 a-3 c, fig. 1 and 2 are schematic structural views of a first

10 in a first embodiment of the invention in a first configuration and a second configuration, respectively, and fig. 3 a-3 c are schematic structural views of a

1, a

2 and a

3, respectively, in a first embodiment of the invention.

In particular, the present embodiment provides a first

10 for use in the occlusion treatment of a vascular tumor, including, but not limited to, an intracranial aneurysm, and also a peripheral aneurysm. In addition, the first

10 of the present embodiment uses an integrated multi-level coil for embolization, which avoids the need for multiple selection of coils of different sizes and configurations during the operation of the physician, thereby reducing the number of operations during the operation, shortening the operation time, and reducing the number of coils used in one operation, thereby reducing the economic burden on the patient.

The first

10 includes at least two spring coil units connected end to end, and optionally, the number of the spring coil units is 2 to 5. It should be understood that the number of coil units is determined primarily by the number of coil units actually required for a procedure, and thus the number of coil units is not particularly required in the present invention.

The following description illustrates three coil units as an example of the first

10 that can improve basket formation and packing, but those skilled in the art will appreciate that the number of coil units in the present embodiment may be two or more than three.

Preferably, the first

10 comprises a first

1, a second

2 and a third

3 which are connected end to end, and each spring coil unit is a sphere formed by winding a body, and is preferably a standard sphere. Preferably, the body is a primary coil, and the primary coil is formed by spirally winding a metal, alloy or polymer wire. The structure of the wire is not particularly limited, and may be a strand formed of a single wire or a plurality of single wires. A "single wire" is a single wire having a circular or other cross-section and extending in a linear fashion. The material of the wire rod is not particularly limited, and the material may be a material opaque to X-rays, such as any one of platinum, rhodium, rhenium, palladium, or tungsten, or an alloy of these metals, or a combination of at least two of these metals or alloys. The "standard sphere" is a round sphere having a substantially constant outer diameter, but is not limited thereto, and the sphere may be a spheroid or the like. Because the spheroid is favorable to reducing the camber of the body of connecting two adjacent spring coil units especially standard spheroid, makes the body gently pass through to next spring coil unit from preceding spring coil unit to reduce the degree of curvature of the body of transition department with the pressure that reduces to the tumor wall, reduce the risk that hemangioma bursts. It will be appreciated here that if the curvature of the body at the transition is large, it is likely to form a tip, causing excessive pressure on the wall of the aneurysm, which tends to cause the aneurysm to rupture.

The first

10 has a first configuration (i.e., a preformed shape) as shown in fig. 1 and a second configuration (i.e., a packed shape or a free state after removal from a sheath) as shown in fig. 2. The second form refers to the final shape imparted to the first form shown in fig. 1. In more detail, one end of the body in the

1 is connected to one end of the body in the

2, the other end of the body in the

2 is connected to one end of the body in the

3, and the body here is usually a primary coil, i.e., a primary coil is wound in the first form shown in fig. 1. When the first

10 is in the first configuration, the three coil spring units are arranged side by side and do not overlap with each other; when the first

10 is in the second configuration, the

2 is disposed inside the

1, and the

3 is disposed inside the

2. In particular, the material coverage per unit area of the

1, the material coverage per unit area of the

2, and the material coverage per unit area of the

3 increase in this order.

When implanted, the

1 is the distal-most end of the first

10, i.e., enters the lesion first, and the

3 is the proximal-most end of the first

10, i.e., enters the lesion last. In the case of an aneurysm, the

1 first enters the aneurysm, the

2, and the

3, and finally fills the aneurysm in the second configuration shown in fig. 2. When the first

10 is applied only by gravity (in a free state, i.e., not constrained by the sheath, nor occluding the lesion), the structure is in the form of the

1 being at the outermost portion, the

2 being inside the first coil unit 1 (i.e., the

2 is located between the

1 and the

3, and defined as an intermediate position), and the

3 being inside the second coil unit 2 (i.e., the

3 being at the innermost portion).

In the present invention, the size of the

1 is not particularly limited, and may be generally set according to the size of a lesion to be embolized. In the case of an aneurysm, as shown in fig. 4a, the maximum outer diameter D1 (i.e., the maximum cross-sectional width) of the

1 is preferably 5mm to 30mm, more preferably the maximum outer diameter D1 of the

1 is 8mm to 24mm, and still more preferably the maximum outer diameter D1 of the

1 is 10mm to 16 mm.

Further, when the first

10 is in the second configuration, the maximum outer diameter of the outer coil unit is preferably 1.2 to 1.5 times the maximum outer diameter of its inner adjacent coil units, i.e., equivalently, when the first

10 is in the first configuration, the maximum outer diameter of the distal coil unit is preferably 1.2 to 1.5 times the maximum outer diameter of the proximal coil unit in any two adjacent coil units. As shown in fig. 4a to 4b, the maximum outer diameter D1 of the first

1 is preferably 1.2 to 1.5 times the maximum outer diameter D2 of the second

2; as shown in FIGS. 4b to 4c, the maximum outer diameter D2 of the second

2 is preferably 1.2 to 1.5 times the maximum outer diameter D3 of the third

3. The advantage of so configuring the outer diameters of two adjacent spring ring units is that one spring ring unit of any two adjacent spring ring units is conveniently and smoothly plugged into the other spring ring unit, the plugging performance is good, meanwhile, compact plugging is conveniently formed, materials are saved, and the cost is reduced.

As shown in fig. 3a, the first

1 is formed by connecting a plurality of first

11 distributed circumferentially in sequence. The

1 is the outermost coil unit in the second form (i.e., the most distal coil unit in the first form), and generally, the number of the

11 is not less than 3, preferably 3 to 8, such as 3, 4, 5, 6, 7, or 8.

As shown in fig. 3b, the second

2 is formed by connecting a plurality of second

21 distributed circumferentially one after another. Since the second

2 serves as the intermediate spring coil unit, the number of the

21 is not particularly limited as long as it is larger than the number of the

11.

As shown in fig. 3c, the third

3 is formed by connecting a plurality of third

31 distributed circumferentially in sequence. Since the

3 serves as the innermost coil unit in the second form (i.e., the most proximal coil unit in the first form), the number of the

31 is not particularly limited as long as it is larger than the number of the

21.

In an embodiment, the first

10 is configured to: the number of the first

11 is 4, the number of the second

21 is 6, and the number of the third

31 is 8. In another embodiment, the first

10 is configured to: the number of the first

11 is 3, the number of the second

21 is 5, and the number of the third

31 is 7.

It is to be understood that the combination of the above-described basic elements is merely a preferred example and is not intended as a limitation of the present invention. In the present embodiment, in order to make the material coverage of the three spring coil units different from each other, the number of the basic units of the three spring coil units is configured to be different from each other, that is, the number of the first

11, the second

21, and the third

31 is sequentially increased, so that a structure in which the material coverage is from thin to dense is formed, and thus, not only is the basket forming effect good, but also the packing performance is more excellent, and therefore, the basket forming and packing performance can be simultaneously considered, and finally, a dense plug in a tumor is formed, and the plug is not easily displaced, and has good support performance. It will also be appreciated that the above definition of dimensions is based on the dimensions in the first configuration.

Referring to fig. 5-6 and 7 a-7 c, fig. 5 and 6 are schematic structural views of a second

20 in a second embodiment of the present invention in a first configuration and a second configuration, respectively, and fig. 7 a-7 c are schematic structural views of a

1, a

2 and a

3, respectively, in a second embodiment of the present invention.

Specifically, the present embodiment provides a second

20 for use in the occlusion treatment of a vascular tumor, including, but not limited to, intracranial aneurysm, and also peripheral vascular tumor. In addition, the second

20 of the present embodiment uses an integrated multi-level coil for embolization, which avoids the need for multiple selection of coils of different sizes and configurations during the operation of the physician, thereby reducing the number of intraoperative procedures, shortening the operation time, and reducing the number of coils used in a single operation, thereby reducing the economic burden on the patient.

The second

20 includes at least two spring coil units connected end to end, and optionally, the number of the spring coil units is 2 to 5. It should be understood that the number of spring coil units in this embodiment is also determined by the number of spring coil units actually required for a single operation.

The following description illustrates three coil units as an example of the improvement in basket formation and packing performance of the second

20, but those skilled in the art will recognize that the number of coil units in the present embodiment may be two or more than three.

Preferably, the second

20 comprises a

1, a

2 and a

3 which are connected end to end, each coil unit is a spindle body formed by spirally winding a body, and the structure of the body is the same as that of the first embodiment and will not be described in detail. Different from the first embodiment, this embodiment designs every spring coil unit as the spindle, because the spindle has the characteristics that both ends are little, the centre is big for this kind of structure has good location support nature, becomes basket performance good, also is favorable to connecting the body of adjacent spring coil unit department and gently transiting to next spring coil unit by preceding spring coil unit.

The second

20 has a first configuration (i.e., a preformed shape) as shown in fig. 5 and a second configuration (i.e., a packed shape or a free state after removal from the sheath) as shown in fig. 6. The second form refers to the final shape imparted to the first form shown in fig. 5. In more detail, one end of the body of the

1 is connected to one end of the body of the

2, and the other end of the body of the

2 is connected to one end of the body of the

3, and the body here is generally a primary coil, that is, a primary coil is wound in the first form shown in fig. 5, similarly to the embodiment. When the second

20 is in the first configuration, the three coil spring units are arranged side by side and do not overlap with each other; when the second

20 is in the second form, the

2 is disposed inside the

1, and the

3 is disposed inside the

2. Further, as in the first embodiment, the material coverage per unit area of the

1, the material coverage per unit area of the

2, and the material coverage per unit area of the

3 of the present embodiment are sequentially increased.

When implanted, the

1 is the distal-most end of the second

20, i.e., enters the lesion first, and the

3 is the proximal-most end of the second

20, i.e., enters the lesion last. In the case of an aneurysm, the

1 first enters the aneurysm, the

2, and the

3, and finally fills the aneurysm in the second configuration shown in fig. 6. When the second

20 is only under the action of gravity (in a free state, i.e., not constrained by the sheath, nor occluding the lesion), the structure is presented in the form of the

1 being at the outermost portion, the

2 being inside the

1, and the

3 being inside the second coil unit 2 (i.e., the

3 being at the innermost portion).

In addition, the size of the

1 in this embodiment is also set according to the size of the lesion site to be embolized. In the case of an aneurysm, as shown in fig. 7a and 8a, the maximum outer diameter D1 (i.e., the maximum cross-sectional width) of the

1 of the present embodiment is preferably 5mm to 30mm, more preferably 8mm to 24mm, and still more preferably 10mm to 16 mm.

Furthermore, the maximum cross-sectional area of each spring ring unit is preferably 2-3 times of the minimum cross-sectional area, so that the spring ring units are configured to form a spindle body structure with small two ends and large middle, the forming stability is good, the support performance is good, and the spring ring units are not easy to crush when being filled in a tumor. Specifically, the maximum outer diameter D1 of the first

1 is 2-3 times of the minimum outer diameter D1, the maximum outer diameter D2 of the second

2 is preferably 2-3 times of the minimum outer diameter D2, and the maximum outer diameter D3 of the third

3 is 2-3 times of the minimum outer diameter D3.

Further, when the second

20 is in the second configuration, the minimum cross-sectional area of the outer coil unit is preferably 1 to 1.5 times the maximum cross-sectional area of its inner adjacent coil unit, i.e., equivalently, when the second

20 is in the first configuration, the minimum cross-sectional area of the distal coil unit is preferably 1 to 1.5 times the maximum cross-sectional area of the proximal coil unit in any two adjacent coil units. For example, the minimum outer diameter D1 of the first

1 is 1 to 1.5 times the maximum outer diameter D2 of the second

2, and the minimum outer diameter D2 of the second

2 is 1 to 1.5 times the maximum outer diameter D3 of the third

3. The arrangement is convenient for the spring coil unit to smoothly fill and enter another spring coil unit.

Further, in order to make the material coverage rates per unit area of the three spring coil units different from each other, the present embodiment configures the spiral pitches of the three spring coil units to be different from each other, that is, the spiral pitch P1 of the first

1, the spiral pitch P2 of the second

2, and the spiral pitch P3 of the third

3 are sequentially decreased, it is also understood that the spiral pitch of the inner spring coil unit is smaller than the spiral pitch of the outer adjacent spring coil unit thereof, or in any two adjacent spring coil units, the spiral pitch of the proximal spring coil unit is smaller than the spiral pitch of the distal spring coil unit. Preferably, the spiral pitch of the external spring coil unit is 1.5-2 times of the spiral pitch of the internal adjacent spring coil unit. Specifically, the spiral pitch P1 of the first

1 is 1.5-2 times of the spiral pitch P2 of the second

2, and the spiral pitch P2 of the second

2 is 1.5-2 times of the spiral pitch P3 of the third

3. Thus, by adjusting the helical pitch, the second

20 of the present embodiment is formed with a structural feature from thin to dense material coverage from outside to inside. It should be understood that the spiral pitch of the spring coil unit does not refer to the spiral pitch of the primary coil, but refers to the pitch when the primary coil is re-spirally wound.

Furthermore, in order to make the material coverage rate per unit area of the first

1 low, the spiral pitch P1 of the first

1 is preferably 3-5 times of the outer diameter of the primary coil, so that the first

1 can achieve both the support property and the packing property; if the spiral pitch P1 is too large, the material coverage rate is small, the structure is softer, and the supporting performance is weak; if the helical pitch P1 is too small, the material coverage is high, but the structure is relatively stiff and detrimental to packing of subsequent spring coil units. Since the

1 mainly functions to form a support skeleton, the support effect is better, and therefore, in order to balance the support and the packing performance, the spiral pitch P1 of the

1 is designed to be 3-5 times of the outer diameter of the primary coil. Furthermore, the ratio of the height H1 of the first

1 to the maximum outer diameter D1 (i.e. the maximum width) is preferably 1-1.5, and the supporting effect in the tumor is good.

Further, in order to make the material coverage rate of the unit area of the second

2 higher, the spiral pitch P2 of the second

2 is preferably 2-2.5 times of the outer diameter of the primary coil, so that the spring coil unit with higher material coverage rate can be obtained, and the packing effect is ensured. In addition, the ratio of the height H2 of the second

2 to the maximum outer diameter D2 (namely, the maximum width) is preferably 1-1.5, and the supporting effect in the tumor is good.

Further, in order to make the material coverage rate per unit area of the third

3 higher, the spiral pitch P3 of the third

3 is preferably 1-1.2 times of the outer diameter of the primary coil, so that the spring coil unit with higher material coverage rate can be obtained, and the packing density is further improved. In addition, the ratio of the height H3 of the third

3 to the maximum outer diameter D3 (i.e. the maximum width) is 1-1.5, so as to further improve the support property in the tumor.

In particular, the present embodiment provides a third

30 for use in the occlusive treatment of hemangiomas, including, but not limited to, intracranial aneurysms, and also peripheral hemangiomas. In addition, the third

30 of the present embodiment uses an integrated multi-level coil for embolization, which avoids the need for multiple selection of coils of different sizes and configurations during the operation of the physician, thereby reducing the number of intraoperative procedures, shortening the operation time, and reducing the number of coils used in a single operation, thereby reducing the economic burden on the patient.

The third

30 includes at least two end-to-end connected spring coil units, and optionally, the number of the spring coil units is 2 to 5. The number of spring coil units in this embodiment is also determined by the number of spring coil units actually required for a single operation.

The following description illustrates three coil units as an example of the ability of the third

30 to improve basket and packing performance, but those skilled in the art will appreciate that the number of coil units in the present embodiment may be two or more than three.

Preferably, the third

30 includes a

1, a

2 and a

3 connected end to end, each coil unit is a polyhedron wound from a body, which is referred to as the first embodiment and will not be described in detail. In this embodiment, the polyhedron is at least a tetrahedron, and each spring coil unit is formed by connecting a plurality of basic units in sequence, and the basic units are respectively distributed in different planes. The polyhedron has better supporting force, and the stability of the spring coil unit can be ensured.

The third

30 has a first configuration shown in fig. 9 and a second configuration shown in fig. 10. The second form refers to the final shape imparted to the first form shown in fig. 9. In more detail, one end of the body in the

1 is connected to one end of the body in the

2, the other end of the body of the

2 is connected to one end of the body of the

3, and the body is generally a primary coil, i.e., a primary coil is wound in the first form shown in fig. 9. When the third

30 is in the first configuration, the three coil spring units are arranged side by side and do not overlap with each other; when the third

30 is in the second configuration, the

2 is disposed inside the

1, and the

3 is disposed inside the

2. Also, as in the first embodiment, the material coverage per unit area of the

1, the material coverage per unit area of the

2, and the material coverage per unit area of the

3 of the present embodiment are sequentially increased.

When implanted, the

1 is the distal-most end of the third

30, i.e., enters the lesion first, and the

3 is the proximal-most end of the third

30, i.e., enters the lesion last. In the case of an aneurysm, the

1 first enters the aneurysm, the

2, and the

3, and finally fills the aneurysm in the second configuration shown in fig. 10. When the third

30 is only under the action of gravity (in a free state, i.e., not constrained by the sheath, nor occluding the lesion), the structure is in the form of the

1 being at the outermost portion, the

2 being inside the

1, and the

3 being inside the second coil unit 2 (i.e., the

3 being at the innermost portion).

In addition, the size of the

1 in this embodiment is also set according to the size of the lesion site to be embolized. In the case of an aneurysm, as shown in fig. 12, the maximum outer diameter D1 (i.e., the maximum cross-sectional width) of the

1 of the present embodiment is preferably 5mm to 30mm, more preferably the maximum outer diameter D1 of the

1 is 8mm to 24mm, and still more preferably the maximum outer diameter D1 of the

1 is 10mm to 16 mm. Preferably, the ratio of the length, the height and the width (the size of each plane) of each spring coil unit is 1, namely, the spring coil unit is similar to a cubic structure, and the positioning performance of the structure is good.

Preferably, the maximum cross-sectional area of the outer coil unit is 1.2 to 1.5 times the maximum cross-sectional area of its inner adjacent coil unit when the third

30 is in the second configuration, i.e., the maximum cross-sectional area of the distal coil unit is 1.2 to 1.5 times the maximum cross-sectional area of the proximal coil unit in any two adjacent coil units when the third

30 is in the first configuration. For example, the maximum outer diameter D1 of the first

1 is 1.2-1.5 times the maximum outer diameter D2 of the second

2, and the maximum outer diameter D2 of the second

2 is 1.2-1.5 times the maximum outer diameter D3 of the third

3; therefore, one spring ring unit can conveniently enter the other spring ring unit smoothly, compact packing is conveniently formed, materials can be saved, and cost is reduced.

As shown in fig. 11a, for the first

1, the

40 is prepared, then the

40 starts to wind from the starting point, first a first basic unit is wound on the

11, then a second basic unit is continuously wound on the

12, then a third basic unit is continuously wound on the

13, and finally a fourth basic unit is wound on the

14, thereby obtaining a tetrahedron. Wherein the

11 is adjacent to the

12, the

13 is adjacent to the

12 and parallel to the

11, and the

14 is parallel to the

12. As shown in fig. 11b, the secondary

2 is a pentahedron formed by winding the

40 in five planes in sequence. As shown in fig. 11c, the

3 is a hexahedron formed by winding the

40 on six faces in sequence.

Therefore, in the present embodiment, in order to make the material coverage per unit area of the three spring coil units different from each other, the number of the basic units of the three spring coil units is configured to be different from each other, that is, the number of the basic units of the first

1 is smaller than the number of the basic units of the second

2, and the number of the basic units of the second

2 is smaller than the number of the third

2, thereby forming a structure in which the material coverage is from thin to dense from outside to inside.

It is to be understood that the number of basic units of the first

1 is at least 4, preferably 4 to 8. While the number of the base units of the second

2 is not limited to 5 as long as it is larger than the number of the base units of the first

1, the number of the base units of the third

3 is not limited to 6 as long as it is larger than the number of the second

2, for example, the number of the base units of the second

2 may also be 6, 8 or more, and the number of the base units of the third

2 may also be 8 or more.

1. A medical implant comprising at least two spring coil units connected end to end, at least two of said spring coil units having different material coverage per unit area;

the medical implant has a first configuration and a second configuration; when the medical implant is in the first shape, at least two spring coil units are arranged side by side and do not overlap with each other; when the medical implant is in the second configuration, the high material coverage per unit area coil unit is disposed within the low material coverage per unit area coil unit.

2. The medical implant of claim 1, comprising at least three coil units connected end to end in series, the at least three coil units having sequentially increasing material coverage per unit area; when the medical implant is in the second state, the coil unit with high material coverage per unit area is disposed inside the coil unit with low material coverage per unit area in any two adjacent coil units.

3. The medical implant of claim 2, wherein the number of coil units is three, being a first coil unit, a second coil unit, and a third coil unit; the first spring ring unit, the second spring ring unit and the third spring ring unit are sequentially connected end to end; the secondary coil unit is disposed within the primary coil unit and the tertiary coil unit is disposed within the secondary coil unit when the medical implant is in the second configuration.

4. The medical implant of claim 2 or 3, wherein at least three of the coil units are identical in shape and are each a sphere, polyhedron or spindle, or are different in shape and are a combination of a sphere, polyhedron and spindle.

5. The medical implant of claim 4, wherein when at least three of the coil units are shaped differently from each other and the medical implant is in the second configuration, the outermost one of the coil units is a polyhedron, the middle at least one of the coil units is a sphere, and the innermost one of the coil units is a spindle.

6. The medical implant of claim 1 or 2, wherein at least two of the spring coil units are shaped differently from each other or from each other.

7. The medical implant of claim 1 or 2, wherein each of the coil units is connected sequentially from a plurality of base units to a polyhedron, and the outermost coil unit is connected sequentially from at least four base units to a polyhedron when the medical implant is in the second configuration, or each of the coil units is connected sequentially from a plurality of base units to a sphere, and the outermost coil unit is connected sequentially from at least three base units to a sphere when the medical implant is in the second configuration; wherein:

when the medical implant is in the second configuration, the number of base units of the internal coil unit is greater than the number of base units of its external adjacent coil units.

8. The medical implant of claim 7, wherein the shape of the base unit in each coil unit is at least partially different when each coil unit is polyhedral.

9. The medical implant of claim 8, wherein each spring coil unit comprises a C-shaped base unit and an omega-shaped base unit, the omega-shaped base unit being an open loop having an opening arc less than the opening arc of the C-shaped base unit.

10. The medical implant of claim 7, comprising at least three coil units connected end to end, the number of basic units of the at least three coil units increasing sequentially;

when the medical implant is in the second configuration, the coil unit with the larger number of base units is disposed inside the coil unit with the smaller number of base units, among any two adjacent coil units.

11. The medical implant of claim 10, wherein when each of the coil units is a sphere, and the medical implant is in the second configuration, the number of base units of the outermost coil unit is 3 to 8;

when each of the coil units is polyhedral and the medical implant is in the second configuration, the number of the basic units of the outermost coil unit is 4 to 8.

12. The medical implant of claim 7, wherein when each of the coil units is polyhedral, the ratio of the length, height, and width of any one coil unit is 1.

13. The medical implant of claim 1 or 2, wherein the maximum cross-sectional area of an external coil unit is 1.2 to 1.5 times the maximum cross-sectional area of its internal adjacent coil unit when the medical implant is in the second configuration.

14. The medical implant of claim 1 or 2, wherein the outermost coil unit has a maximum cross-sectional width of 5-30 mm when the medical implant is in the second configuration.

15. The medical implant of claim 1 or 2, wherein the number of spring coil units is 2 to 5.

16. The medical implant of claim 1 or 2, wherein each of the spring coil units is spirally wound from a body, and each of the spring coil units is a spindle body with small ends and a large middle; wherein: when the medical implant is in the second configuration, the helical pitch of the internal coil unit is less than the helical pitch of its external adjacent coil units.

17. The medical implant of claim 16, wherein the helical pitch of an external coil unit is 1.5-2 times the helical pitch of its internal adjacent coil units when the medical implant is in the second configuration.

18. The medical implant of claim 16, wherein the ratio of the height to the maximum width of each spring coil unit is 1-1.5.

19. The medical implant of claim 16, wherein the maximum cross-sectional area of each spring coil unit is 2-3 times the minimum cross-sectional area.

20. The medical implant of claim 16, wherein the minimum cross-sectional area of an external coil unit is 1-1.5 times the maximum cross-sectional area of its internal adjacent coil units when the medical implant is in the second configuration.

21. The medical implant of any of claims 16-20, wherein the number of coil units is three, being a first coil unit, a second coil unit, and a third coil unit; the first spring ring unit, the second spring ring unit and the third spring ring unit are sequentially connected end to end; when the medical implant is in the second configuration, the secondary coil unit is disposed within the primary coil unit, and the tertiary coil unit is disposed within the secondary coil unit; wherein:

the spiral pitch of the first spring ring unit is 3-5 times of the outer diameter of the body; the spiral pitch of the second spring ring unit is 2-2.5 times of the outer diameter of the body; the spiral pitch of the third spring ring unit is 1-1.2 times of the outer diameter of the body.

22. The medical implant of claim 1 or 2, wherein each spring coil unit is wound from a primary coil that is helically wound from a metal, alloy or polymer wire.

23. A method of manufacturing a medical implant for preparing a medical implant according to any of claims 1-22, the method comprising:

providing a body;

the body is made to run according to a mold, so that at least two spring ring units connected end to end are formed in the mold in a winding mode, the material coverage rate of the unit area of the spring ring units is different in at least two spring ring units in the winding process, and the spring ring units with high material coverage rate of the unit area can be arranged in the spring ring units with low material coverage rate of the unit area.

24. The method of claim 23, wherein the body is wound sequentially into a plurality of base units on the mold during the winding process, and the plurality of base units are sequentially connected to form at least two spring coil units, wherein at least two spring coil units have different numbers of base units.

25. The method of manufacturing a medical implant according to claim 24, wherein at least two polyhedrons, each constituting one coil unit, are formed by connecting a plurality of the basic units in sequence, or at least two spheres, each constituting one coil unit, are formed by connecting a plurality of the basic units in sequence.

26. The method of claim 23, wherein the body is helically wound on the mold to form at least two spindles, each of the spindles forming a spring coil unit, and at least two of the spindles having different helical pitches during the winding process.

27. The method of manufacturing a medical implant according to any of claims 23-26, wherein the body is wound on the mold to form at least three end-to-end connected spring coil units, the at least three spring coil units having sequentially increasing material coverage per unit area; in any two adjacent spring coil units, the spring coil unit with high material coverage per unit area can be arranged inside the spring coil unit with low material coverage per unit area.

28. The method of any one of claims 23-26, wherein the body is a primary coil formed by helically winding a metal, alloy or polymer wire.