隨著時代演進，現代人使用3C產品的時間越來越長，根據中華眼科醫學會統計，台灣人平均一天使用3C產品時間高達8.7小時；而根據美國Vision Council統計，美國人平均使用3C產品的時間一天更高達9小時。研究指出，長時間使用3C產品，罹患白內障、青光眼的機率會大幅提高。因為眼睛盯著螢幕時，容易造成眼睛肌肉的緊繃，使眼睛更加疲累，導致視覺模糊或是眼壓增高。在人眼的屈光系統中，角膜的屈光能力是最強的，與水晶體共同負責將光線聚焦於視網膜上。由於角膜細薄的層狀結構，其機械特性在維持角膜形狀中扮演非常重要的角色。目前所知的角膜異常病變主要為青光眼、角膜炎、圓錐角膜以及接受雷射原位角膜磨鑲術所引起的角膜擴張。眼反應分析儀(ORA)是目前臨床上唯一能夠以非接觸方式量測角膜生物力學的醫療儀器，可以推算出表示角膜機械特性的角膜滯後參數，ORA也因此被視為量測角膜機械特性的黃金準則。然而，ORA所測得的滯後參數並未考量複雜的生物結構，且與實際生物力學的關係也尚未明確，因此並不能直接對應於角膜的黏彈參數，在臨床的應用上有非常大的限制。除此之外，眼壓是臨床眼科檢測的重要參數，特別是用於評估青光眼，但因每個人角膜機械性質的個體差異，使得目前臨床所使用的張力計所量測到的眼壓並不準確。
有鑑於此，本研究提出一個使用陣列式高頻超音波萊姆波彈性影像系統用於估計豬眼角膜組織黏彈特性，主要會使用到一個外部震盪器作為低頻(100-1000 Hz)組織震動的來源，以及一個40 MHz高頻超音波換能器與超快速超音波成像系統來追蹤剪切波動的傳遞情況。此實驗中會配製兩種不同硬度及厚度的仿體用來驗證實驗架構和演算法的可行性，而其結果也表明此方法是具有可靠性，且計算出來的彈性與黏性與機械測試的結果比起傳統使用剪切波模型來的準確。在動物實驗上，使用新鮮豬眼進行量測，分為正常組與局部硬化組，局部硬化組使用福馬林注射使之硬化，結果顯示此技術能有效的分辨出眼角膜裡不同區域的軟硬程度。

As time progresses, continuous development, modern people spend a lot of time using 3C products. According to the Ophthalmological Society of Taiwan statistics, the average time of Taiwanese using 3C products is up to 8.7 hours per day. According to Vision Council of America, the average time of American using 3C products is up to 9 hours per day. Some studies have shown, the long-term use 3C products will increase the probability of having cataracts and glaucoma. Because when you stare at the screen, it is easy to cause tension in the eye muscles and making the eyes more tired, resulting in blurred vision or increased intraocular pressure. The refractive ability of cornea is the strongest in the human eye, and it is responsible for focusing the light on the retina with the lens. Due to the corneal structure is thin and lamellar, the mechanical properties of cornea are important for maintaining the corneal shape. The most common ophthalmic pathologies are such as glaucoma, keratitis, keratoconus, and corneal ectasia caused by LASIK. Thus far, an ocular response analyzer (ORA) is the most commonly to use to measure the mechanical properties via corneal hysteresis curves. ORA is regarded as the gold standard for measuring the mechanical properties of the cornea. However, ORA cannot quantitatively measure corneal viscoelasticity because it does not consider about complex structure. There are very large limitations in clinical diagnosis. In addition, intraocular pressure is an important parameter for clinical ophthalmology, especially for the evaluation of glaucoma. But due to the individual differences in the mechanical properties of each person's cornea, the intraocular pressure measured by the tonometry currently in clinical is not accurate.
In summary, this study proposes a high-frequency ultrafast ultrasound imaging system combined Lamb wave model for estimating the viscoelastic of porcine cornea. An external-vibration will be used as a source of low-frequency (100-1000 Hz) vibration for producing tissue motion, and an ultrafast ultrasound imaging system with 40 MHz high-frequency ultrasound transducer will be used for detecting the shear wave propagation in the tissue. In this experiment, two different weight percentage concentrations and thickness gelatin phantoms will be prepared to verify the feasibility of the experiment. All the results are shown that the method is reliable, and the elasticity and viscosity are compared with mechanical test, which is more accurate than shear wave model. In animal experiments, fresh porcine eyes were used for measurement. The samples are divided into normal group and local sclerosis group. The artificial induction of sclerosis in the cornea by formalin injection results in significant deformation and expansion. The results showed that this technique could distinguish the stiffness of different areas of the cornea.

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