在臨床醫學中，對於大血管阻塞的急性缺血性腦中風病人，利用血管內介入治療(endovascular therapy) 比靜脈施打血栓溶解劑的策略，有明顯預後的改善。 然而只有少數綜合中風中心有能力進行血管內治療。根據中風症狀嚴重程度和地理資訊，我們使用隨機規劃模型發展繞道策略，以決定病人送往的醫院。我們可以進一步考慮減少或是增加EVT資源的政策。

The prognosis performance of endovascular therapy (EVT) is shown better than thrombolysis in the patients with acute ischemic stroke (AIS) caused by large vessel occlusion (LVO) in recent clinical medical research. Yet EVT resources are available only in a few number of comprehensive stroke centers (CSCs). According to stroke symptom severity and geographic information, we develop a bypass strategy for AIS patients using a stochastic programming model to decide a comprehensive stroke center where the patient should be sent. Policy of reduction or expansion of EVT hospitals can further be facilitated.

Chapter 1 Introduction 1
Chapter 2 Literature Review 5
2.1 Types of strokes 5
2.2 Stroke treatments 6
2.3 Prehospital transport 7
Chapter 3 Methods 9
3.1 Study design and setting 9
3.2 Coverage and overlapping rates estimation 11
3.3 Bypass strategy and AHA guideline 12
3.4 Resource redistribution 13
3.4.1 Reduction of CSCs 13
3.4.2 Expansion of CSCs 15
3.5 Process Time Minimization Model 15
3.6 EVT Capacity Expansion Model 18
Chapter 4 Results 25
4.1 The policy of reduction of CSCs 25
4.2 The policy of expansion of CSCs 30
4.3 Limitation 34
Chapter 5 Conclusions 36
Chapter 6 References 37

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