腦部取栓支架(stent retriever)為一種中空管狀結構的醫療器材，可將
其壓縮到運輸系統(delivery system)內，經由引導導管(guide catheter)
放置到血栓堵塞處，鎳鈦支架從運輸系統釋放後能因人體溫度自行嵌
進血栓內，再進行支架回收，同時將血栓取至導管內，完成機械取栓
術。
本研究使用ANSYS 輔助分析，開發出能實際在取栓系統回收且
能適用蜿蜒腦血管的支架後，使用光纖雷射加工4 mm鎳鈦合金管材，
並搭配高壓空氣切割，降低因雷射導致的熱影響，成功加工出鎳鈦支
架。本研究在使用高溫爐熱處理及電解拋光後，成功增加鎳鈦取栓支
架柔韌性，並在握壓進取栓系統及釋放後，發現所開發的鎳鈦支架能
成功自行擴張釋放至4 mm。本研究並將所開發鎳鈦支架放置到3 mm
彎曲塑膞管內，以模擬腦血管彎曲狀態，發現鎳鈦支架能維持整體結
構完整，沒有因彎曲而受到損壞或變形，且與管壁貼合狀況良好。

The brain stent retriever is a hollow tubular medical device that can be
crimped into a delivery system and placed through a guide catheter to a
thrombus. After the stent is released, it can be embedded in the thrombus
due to the temperature of the vessel blood, then perform mechanical
thrombectomy.
In this study, ANSYS assisted analysis was used to develop a stent that
can be retrieved in the thrombectomy system and can withstand the
cerebrovascular vessels. A nanosecond fiber laser was used to machine a
4 mm Nitinol tube and the process was performed with high-pressure air
to reduce the laser-induced heat affected zone. Nitinol stent retrievers
were fabricated successfully. After high temperature furnace heat
treatment and electropolishing, the flexibility of the retrievable stent was
successfully improved. Then, using the delivery system established for
mechanical thrombectomy, the stent was crimped and released to
investigate its performance. It was found that the fabricated stent can be
released and self-expanded to 4 mm. The stent was also placed in a 3 mm
transparent plastic tube to simulate a blood vessel bending state. The
overall structure was intact, no damage or deformation due to bending
and the wall conformation condition was good.

[1] 廖年晨，”神經內科醫師的另一個藍海 - 動脈取栓”，台灣腦中風
學會，民107 年3 月。
[2] K Boyle, RA Joundi, RI Aviv, " An historical and contemporary
review of endovascular therapy for acute ischemic stroke",
Neurovascular Imaging 3.1 (2017): 1.
[3] 劉祥仁，”急性缺血性腦中風之一般處理原則”，台灣腦中風學會，
民107 年5 月。
[4] CH Fu, JF Liu, A Guo, "Statistical characteristics of surface integrity
by fiber laser cutting of Nitinol vascular stents". Applied Surface
Science 353 (2015): 291-299.
[5] M Baumeister, K Dickmann, T Hoult, "Fiber laser micro-cutting of
stainless steel sheets", Applied Physics A 85.2 (2006): 121-124.
[6] CS Chen, SY Lin, NK Chou, YS Chen, "Optimization of laser
processing in the fabrication of stents", Materials transactions 53.11
(2012): 2023-2027.
[7] RL Novakovic, G Toth, S Narayanan, OO Zaidat , "Retrievable stents,
stentrievers, for endovascular acute ischemic stroke
therapy", Neurology 79.13 Supplement 1 (2012): S148-S157.
[8] D Yang, Y Hao, W Zi, H Wang, "Effect of retrievable stent size on
endovascular treatment of acute ischemic stroke: a multicenter
study", American Journal of Neuroradiology (2017).
[9] MTI solitaire FR revascularization device,衛署醫器輸字第024496
69
號。
[10] DE Hodgson, WH Ming, RJ Biermann, "Shape memory
alloys." ASM International, Metals Handbook, Tenth Edition. 2
(1990): 897-902.
[11] SA Shabalovskaya, "Surface corrosion and biocompatibility aspects
of Nitinol as an implant material", Bio-medical materials and
engineering 12.1 (2002): 69-109.
[12] M Dolce, D Cardone, "Mechanical behaviour of shape memory
alloys for seismic applications 2. Austenite NiTi wires subjected to
tension", International Journal of Mechanical Sciences 43.11 (2001):
2657-2677.
[13] K Otsuka, T Kakeshita, "Science and technology of shape-memory
alloys: new developments", MRS Bulletin 27.2 (2002): 91-100.
[14] AR Pelton, J Dicello, S Miyazaki, "Optimisation of processing and
properties of medical grade Nitinol wire", Minimally Invasive
Therapy & Allied Technologies 9.2 (2000): 107-118..
[15] X Liu, Y Wang, D Yang, M Qi, "The effect of ageing treatment on
shape-setting and superelasticity of a nitinol stent", Materials
Characterization 59.4 (2008): 402-406.
[16] K Wenger, F Nagl, M Wagner, J Berkefeld, "Improvement of stent
retriever design and efficacy of mechanical thrombectomy in a flow
model", Cardiovascular and Interventional Radiology 36.1 (2013):
192-197.
[17] Baasel Lasertech, Starfiber 180 fc oem, Manual.
[18] 高慶隆，”5-French 鎳鈦膽道支架研發”，國立台灣科技大學碩士
70
論文，2017。
[19] 曾暐凱，”生醫支架雷射加工後處理製程改良”，國立台灣科技大
學碩士論文，2017。
[20] AG Osborn, Diagnostic Cerebral Angiography second edition, 1980.
[21] SJ Schreiber, S Gottschalk, M Weih, "Assessment of blood flow
velocity and diameter of the middle cerebral artery during the
acetazolamide provocation test by use of transcranial Doppler
sonography and MR imaging", American Journal of
Neuroradiology 21.7 (2000): 1207-1211.
[22] 陳正宗，”膽管支架之設計與光纖雷射加工”，國立台灣科技大學
碩士論文，2013。