正常眼壓型青光眼為青光眼病症的主要類型之一，多數的青光眼類型皆可以量測眼壓是否過高而察覺異狀，但正常眼壓型青光眼早期多無明顯症狀，且患者眼壓量測值皆位於正常範圍內，相較於一般青光眼病患較不易直接從眼壓上判斷病症。
青光眼是由於眼壓上升超出視神經所能負荷的範圍，使得視神經受損的一種視神經疾病，當眼壓高於視神經所能承受之限度時，便會使得視神經受損產生視野缺損，最後導致失明。目前量測的眼球內部壓力和真實眼壓仍存有誤差，中央角膜厚度即為主要的誤差因素，角膜較厚的患者眼壓容易被高估，反之低估了角膜較薄患者的眼壓，降低了青光眼判定的準確性。
本研究即為運用數值模擬分析的方式，對於正常眼壓型青光眼與角膜厚度的關係進行探討，並模擬患者眼球結構的壓力分佈及眼睛內部房水流動之情形，藉以了解角膜厚度對眼壓量測所造成的影響。

Normal-tension Glaucoma is one of the main types of glaucoma. Most types of glaucoma can be judged by their higher intraocular pressure. But, normal-tension glaucoma (NTG) shows no obvious symptoms, and the intraocular pressure is normal in its early stage. It is hard to tell if one having NTG by simply checking intraocular pressure value.
Glaucoma is a disease of optic nerve caused by increased intraocular pressure. An elevated intraocular pressure may irreversibly damage optic nerve which resulting in a progressive, permanent loss of vision when the pressure exceeds the load of optic nerve. In NTG, the measured value of internal pressure is not the real internal pressure. The major factor to cause this discrepancy is the thickness of central corneal. The thicker is the cornea, the overestimated is the intraocular pressure. The accuracy of the glaucoma diagnosis is then mis-conducted.
This study used numerical simulation to exam the relationship of normal-tension glaucoma and corneal thickness. The pressure distribution and the flow of aqueous humor in ocular structure are found and shown to know more of the impact of the corneal thickness and the value of intraocular pressure measured.

目錄
中文摘要 I
英文摘要 III
目錄 V
圖目錄 VII
表目錄 VIII
第一章 緒論 1
1-1 研究背景與研究動機 2
1-2 文獻回顧 5
第二章 研究方法 7
2-1 有限元素法概述 7
2-2 應用軟體 8
第三章 分析理論 13
3-1 結構分析理論 13
3-2 流場分析理論 17
3-3 收斂檢測 19
第四章 角膜與眼壓量測 20
4-1 角膜 20
4-2 眼壓量測 21
第五章 分析元素、材料參數與邊界條件設定 24
5-1 模型分析元素 24
5-2 模擬材料參數 26
5-3 建立分析模型 28
5-4 初始條件 30
5-5 負載條件 33
第六章 正常眼壓型青光眼之模擬分析 35
6-1 正常眼壓型青光眼 35
6-2 正常眼壓型青光眼之模擬結果 36
第七章 結論與未來展望 41
7-1 結論 41
7-2 未來展望 42
參考文獻 43
專有名詞中英文對照表 48

圖目錄
圖1-1 眼球結構示意圖 2
圖1-2 房水流動示意圖 3
圖2-1 ANSYS分析處理作業流程圖 10
圖2-2 研究過程流程圖 12
圖4-1(A) Imbert-Fick定律示意圖 22
圖4-1(B) Imbert-Fick定律修正示意圖 22
圖5-1 SOLID45元素圖 24
圖5-2 FLUID142元素圖 25
圖5-3 眼球模型尺寸圖 29
圖5-4 眼球模型網格圖 29
圖5-5(A) 房水流場設定圖 31
圖5-5(B) 房水流場設定圖 32
圖5-6 模擬負載條件示意圖 33
圖6-1 前後房壓力分佈圖 37
圖6-2 房水流速分佈圖 37
圖6-3 房水流線分佈圖 38
圖6-4 角膜、水晶體和玻璃體壓力分佈圖 38
圖6-5 不同厚度的角膜壓力比較圖 40

表目錄
表5-1 房水材料參數表 26
表5-2 角膜與水晶體材料參數表 27
表5-3 玻璃體材料參數表 27

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