空心的神經引導導管的使用已經是臨床上周邊神經損傷治療的重要方法，但其無法有效地修復大於2cm的傷口，且因導管能生產的尺寸規格有限，所以無法符合所有的神經直徑，使得手術時間可能增加且影響術後神經癒合速度。此研究提出了創新的神經引導導管設計，使之能吻合多種神經尺寸，藉此降低生產成本且加速手術的進行。同時為了進一步促進神經再生的效率，在導管的內側面加上了線狀表面結構，使此導管能修復更長的神經缺陷。
為了生產此特殊設計之神經引導導管，本實驗開發以液滴塗佈法(Drop-cast)為主的製程，成功地製作出擁有線狀結構的聚乳酸薄膜，並利用溶劑蒸發所產生的應力將薄膜捲曲成管狀。為了瞭解此製程及此製程應用於其他領域之可能性，本實驗也探討了表面結構、溶液濃度以及固化時的溶劑含量對於最終管徑控制的影響，同時展示了利用聚乙烯醇˴金屬模具及玻璃作為母模的可行性，為這個製程和結構的選用提供了更多的選擇。
研究結果顯示液滴塗佈法能夠製作出內面擁有微奈米線狀表面結構的可調整直徑神經引導導管，且利用溶劑的控制，達成最終成品的外徑尺寸控制。因液滴塗佈法是高再現性且具成本效益的製程，所以此方法將有機會達成神經引導導管的大量生產。

Hollow nerve guidance conduits (NGCs) have been approved for the treatment in repairing peripheral nerve injury clinically, but it is not an effective way to repair the nerve defect which is longer than 2cm. Also, the availability of diameter from commercial hollow NGCs is limited, so it can not fit every nerve defect. This will increase the surgery operation time and recovery time.
This research brought out an innovative nerve guidance conduit design, which has an adjustable radial shape to fit different nerve diameter and incorporated directional micro/nano linear groove structures on inner surface to facilitate the nerve regeneration distance.
In order to fabricate this innovative NGCs, the research proposed a drop-cast based process and discussed the relationship between surface structure, initial solvent concentration, the volume fraction of solvent at which the film solidifies and the diameter of conduits. Furthermore, the result showed that glass, polyvinyl alcohol and metal can also be chosen as a substrate for drop-cast process.
According to the experiments, drop-cast process can fabricate the adjustable nerve guidance conduits with inside micro/nano groove patterns, and the diameter of conduits can be controlled by the evaporation of solvent. Drop-cast is also a high reproducible and cost-effective process, so using drop-cast to fabricate patterned nerve guidance conduits is a promising way to achieve mass production.

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