目前在治療結腸阻塞(colonic obstruction)及腸道手術後吻合口之滲漏問題，常會植入自擴式金屬支架(self-expandable stents, SEMS)。但腸道支架置入後，可能產生支架移位(migration)、穿孔(perforation)等併發症，且目前尚無適用於腸道之可降解之支架。
有鑑於此，本論文提出結合3D列印技術，以薄膜型支架模具及光固化充填式技術開發可降解腸道支架。利用可降解高分子材料能完全被人體吸收之特性，藉此降低併發症的發生率，並提供足夠的徑強度以維持腸道的擴張。
本論文使用ANSYS模擬軟體分析腸道支架之徑向力，設計符合腸道規格之支架，並透過3D列印技術以PVA(polyvinyl alcohol, PVA)可快速降解材料製作。利用PCL(polycaprolactone, PCL)覆膜方式製作出薄膜型支架模具，經由收縮測試確認其適用於直徑9F(3mm)的置入系統，接著分別充填三種材料─光固化樹脂、光固化可降解材料PCL-DA(PCL-diacrylate, PCL-DA)，以及添加不同比例碳黑(0.5%以及1%)的PCL-DA等增加PCL-DA之機械強度，藉此探討充填三種材料之支架的徑向力差異。
實驗結果顯示，結合3D列印製作出來的薄膜型支架模具，可成功充填光固化可降解材料，並完成充填式可降解腸道支架。在充填光固化可降解材料方面，PCL-DA添加0.5%碳黑之支架徑向強度明顯比未添加碳黑高出32%，添加1%碳黑強度則可增加89%。與市售之金屬大腸支架相比，本論文所製作的充填式可降解腸道支架，能提供足夠的徑向強度，克服植入式金屬支架的瓶頸，對於腸道支架應用具有一定的貢獻。

At present, self-expandable metal stent (SEMS) is an alternative to emergency surgery in the management of colonic obstruction, but there are still several significant complications after colorectal stent placement.
To solve this problem, this research is trying to integrate 3D printing, the filling mold design and UV curing method for developing biodegradable colonic stents.
Firstly, 3D Printing was used to print a PVA (polyvinyl alcohol, PVA), rapidly degradable stent, and a thin film-type stent mold was made from the rapidly degradation stent. The thin film stent mold was made of flexible and soft biodegradable material, namely PCL (polycaprolactone, PCL), and crimped with a balloon in a delivery system. After the flexible thin film stent mold was deployed and expanded by the balloon, a special UV curable biodegradable gel, made by PCL-DA (PCL-diacrylate, PCL-DA) and photoinitiator, was injected into the mold. After that, the gel in the mold was cured by UV light and formed a biodegradable stent.
To confirm whether the method is feasible, crimping tests and filling tests were performed. It has been proved that the flexible thin film stent mold can be crimped into a 9F (3 mm) diameter stent delivery system. Three kinds of filling materials, a UV curing resin with similar elastic modulus to PLA (polylactic acid, PLA), PCL-DA, and PCL-DA + carbon black were tested in the filling tests. The results has shown that the adding carbon PCL-DA can effectively increase the radial force of stent. It is found that the adding 1% carbon PCL-DA with the increase of radial force, namely 89%. In addition, in this study ANSYS software was used to simulate the radial force of stents. Comparing to current metallic colonic stents, the fabricated biodegradable stents in this study can achieve the same level of radial force, overcoming the shortage of conventional biodegradable stents. This study provides a possible way to develop biodegradable colonic stents in the future.

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