CN111067678A - 一种具有光栅结构的可降解颅内球支架及其制备方法 - Google Patents

一种具有光栅结构的可降解颅内球支架及其制备方法 Download PDF

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CN111067678A
CN111067678A CN202010135756.2A CN202010135756A CN111067678A CN 111067678 A CN111067678 A CN 111067678A CN 202010135756 A CN202010135756 A CN 202010135756A CN 111067678 A CN111067678 A CN 111067678A
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倪中华
赵古田
陈鹤
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Nanjing Haoyandingye Technology Co Ltd
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    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
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    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/82—Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
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    • A61F2/915—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
    • A61F2002/9155—Adjacent bands being connected to each other
    • A61F2002/91566—Adjacent bands being connected to each other connected trough to trough
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
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    • A61F2210/0004—Particular material properties of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof bioabsorbable
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Abstract

本发明公开了一种具有光栅结构的可降解颅内球支架，包含波浪形圆环结构、连接杆，所述波浪形圆环结构由若干平行设置的波浪形环形支杆构成，所述支杆之间通过连接杆相连，形成闭合的环状的颅内球支架，波浪形圆环结构、连接杆均由可非金属生物吸收可降解材料制成；所述波浪圆环结构、连接杆的周向设有光栅结构，用于提高直接与血管的兼容性，防止溶血，促进内皮化。

Description

一种具有光栅结构的可降解颅内球支架及其制备方法
技术领域
本发明属于属于医疗领域，具体涉及一种具有光栅结构的可降解颅内球支架及其制备方法。
背景技术
目前作为治疗包括脑梗塞的主要医疗器械，药物涂层支架本体一直采用惰性金属材料，多以316L医用不锈钢、钴铬合金为主，此类金属支架作为异源性物质植入脑部将一直存留于人体，当发生再狭窄时使治疗变得更加棘手。而且目前作为药物载体的高分子也是不可降解的材料，在药物释放以后也将永远存留于人体，对一些病人会引 起致命的亚急性栓塞或后期血栓。
因此，研究采用一种可生物可降解材料作为支架的本体材料，使其具有金属支架的各种力学性能，且不改变现在采用的输送方法，成为微创介入医疗器械领域目前的另一个研究的热点领域。生物可降解支架在植入脑内病变位置后，可以实现金属支架的支撑功能，在其所载治疗药物释放完全后，其本体可在一段时间内逐步降解为可以被人体所吸收且无毒副作用的物质，直至完全降解。
但目前可降解支架的生物相容性仍不理想，支架植入后容易在局部引发溶血、炎症等副作用，因此需要通过改善支架的表面性能来优化支架的生物相容性。
发明内容
为解决上述问题，本发明公开了一种具有光栅结构的可降解颅内球支架及其制备方法，提高直接与血管的兼容性，防止溶血，促进内皮化。
为达到上述目的，本发明的技术方案如下：
一种具有光栅结构的可降解颅内球支架，包含：波浪形圆环结构、连接杆，所述波浪形圆环结构由若干平行设置的波浪形环形支杆构成，所述支杆之间通过连接杆相连，形成闭合的环状的颅内球支架。波浪形圆环结构、连接杆均由可非金属生物吸收可降解材料制成；所述波浪圆环结构、连接杆的周向设有光栅结构，用于提高直接与血管的兼容性，防止溶血，促进内皮化。
一种具有光栅结构的可降解颅内球支架，所述光栅结构为交替的山峰，凹槽组合。相邻两个山峰顶部的间距D为10-20 um，相邻两个凹槽的底部间距也为20um。
一种具有光栅结构的可降解颅内球支架，所述山峰顶部具有一定宽度，为5-10um。凹槽底部也具有一定的宽度，为5-10um。
一种具有光栅结构的可降解颅内球支架，凹槽的深度为2-7um。
一种具有光栅结构的可降解颅内球支架，可降解材料为为可降解聚合物材料，包括：聚左旋乳酸PLLA、聚(乳酸-乙醇酸)共聚物PLGA或聚（L-丙交酯-共-乙交酯）（PLLA-共-PDLA比例为70:30）。
一种具有光栅结构的可降解颅内球支架，所述光栅结构采用1064nm、532nm以及355nm的激光同时扫描支架外表面制备，1064nm激光的光斑直径为30um,532nm和355nm激光的光斑直径为20.5um。1064nm激光能量为2.5uJ，532nm和355nm激光能量为1.5uJ。1064nm激光和532nm激光的聚焦镜焦距小于355nm激光聚焦镜的焦距。通过调整激光的脉宽、输出频率、以及不同波长激光光斑间的搭接率来调整凹槽和山峰的宽度。
本发明的有益效果是：
（1）光栅结构具有有载药功能，使支架载药能力增强；
（2）光栅结构能够促进内皮化，改善药物带来的副作用；
（3）光栅结构结具有绝佳的生物兼容性，具有抗溶血、抗血栓、抗炎症的功能。
附图说明
图1 是光栅结构示意图；
图2 可降解颅内球支架结构示意图。
附图标记列表：
1、光栅结构；2、山峰；3、凹槽；4、波浪环形结构；5、连接杆。
具体实施方式
下面结合附图和具体实施方式，进一步阐明本发明，应理解下述具体实施方式仅用于说明本发明而不用于限制本发明的范围。
实施例1：
一种具有光栅结构的可降解颅内球支架，包含：包含波浪形圆环结构4、连接杆5，波浪形圆环结构4通过连接杆5相连，形成闭合的环状的颅内球支架（波浪形圆环结构由若干平行设置的波浪形环形支杆构成）。波浪形圆环结构4、连接杆5均由可非金属生物吸收可降解材料制成。所述波浪圆环结构4、连接杆5的周向设有光栅结构，用于提高直接与血管的兼容性，防止溶血，促进内皮化。
光栅结构1为交替的山峰2，凹槽3组合。相邻两个山峰1顶部的间距D为10-20 um，相邻两个凹槽2的底部间距也为20um。
所述山峰2顶部具有一定宽度，为5-10um。凹槽3底部也具有一定的宽度，为5-10um。凹槽的深度为2-7um。
所述光栅结构1采用1064nm、532nm以及355nm波长的激光同时扫描支架外表面制备，1064nm激光的光斑直径为30um, 532nm和355nm激光的光斑直径为20.5um。1064nm激光能量为2.5uJ，532nm和355nm激光能量为1.5uJ。1064nm激光和532nm激光的聚焦镜焦距小于355nm激光聚焦镜的焦距。通过调整激光的脉宽、输出频率、以及不同波长激光光斑间的搭接率来调整凹槽和山峰的宽度。波浪环状结构4及连接杆5由非金属可降解材料制成，支架植入一段时间后，会自动降解消失，无残留。
本发明方案所公开的技术手段不仅限于上述实施方式所公开的技术手段，还包括由以上技术特征任意组合所组成的技术方案。

Claims (5)

1.一种具有光栅结构的可降解颅内球支架，包含波浪形圆环结构、连接杆，所述波浪形圆环结构由若干平行设置的波浪形环形支杆构成，所述支杆之间通过连接杆相连，形成闭合的环状的颅内球支架，波浪形圆环结构、连接杆均由可非金属生物吸收可降解材料制成；其特征在于：所述波浪圆环结构、连接杆的周向设有光栅结构。
2.根据权利要求1所述的一种具有光栅结构的可降解颅内球支架，其特征在于，所述光栅结构为交替的山峰、凹槽组合；相邻两个山峰顶部的间距D为10-20 um，相邻两个凹槽的底部间距也为20um。
3.根据权利要求2所述的一种具有光栅结构的可降解颅内球支架，其特征在于，所述山峰顶部宽度为5-10um，凹槽底部的宽度也为5-10um。
4.根据权利要求2所述的一种具有光栅结构的可降解颅内球支架，其特征在于，所述凹槽的深度为2-7um。
5.根据权利要求1所述的一种具有光栅结构的可降解颅内球支架，其特征在于，所述光栅结构采用1064nm、532nm以及355nm的激光同时扫描支架外表面制备，1064nm激光的光斑直径为30um，所述532nm和355nm激光的光斑直径为20.5um，所述1064nm激光能量为2.5uJ，所述532nm和355nm激光能量为1.5uJ，1064nm激光和532nm激光的聚焦镜焦距小于355nm激光聚焦镜的焦距，通过调整激光的脉宽、输出频率、以及不同波长激光光斑间的搭接率来调整凹槽和山峰的宽度。
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