為了量化軟組織之剛性，本論文希望發展一個可使用於臨床上的壓痕儀器以量測軟組織的剛性。實驗將以豬肝作為離體（in-vitro）實驗樣本，選擇豬肝是因為取得方便且尺寸與人類相似，選擇肝臟這個器官則是因為肝臟有肝硬化的問題，適合做為本研究的實驗樣本。本論文設計了筆型探棒的機構以及選擇相關元件做成超音波壓痕儀器，以豬肝作為實驗樣本，嘗試進行離體（
in-vitro）實驗並驗證其可行性。
首先，使用材料測試機以特定推進速率分別量測正常與因結凍而硬化的豬肝之有效楊氏係數，除了可確認本研究的數學模型可以成功地分辨正常與硬化之豬肝外
，還能以此建立標準化的數據。之後再以人手推進筆型探棒，同樣地計算有效楊氏係數，並與標準化的數據做比較。實驗發現，本研究可以透過實驗數據辨別正常與硬化的豬肝，且經由人手驅動筆型探棒而得到的有效楊氏係數（4,040 ± 656 Pa）大於標準化的數據（1,758 ± 574 Pa at 1.0mm/s）。本文推測這是因為人手控制探棒不易且推進速率高於標準實驗的緣故，使得量測結果大於標準數據將近1.5倍。但若計算其變異係數（coefficient of variation），則人手驅動的結果（
16%）優於標準化的數據（33%），這顯示出手動量測具有較佳的一致性。
由實驗結果可知，若人手能以適當的速率推進筆型探棒以量測軟組織之受力-變形行為，則超音波壓痕儀器可以客觀地量化軟組織的剛性。

For quantification of stiffness of soft tissues, we develop a measuring device and hope could be used in clinical application. The in-vitro experiment object is porcine liver. We choose it because of its convenience to obtain and its size similar to human beings. In addition many patients in Taiwan have liver cirrhosis problems and porcine liver is comportable to be an experiment object.
We design and improve related elements including pen-size probe, load cell and so forth based on works found in the literature. The porcine liver is chosen for in-vitro experiment object. First, using material testing system (MTS) in specific indentation rate evaluates the apparent Young’s modulus of normal and frozen liver were evaluated individually to verify whether the mathematical model in this thesis is feasible to differentiate these two kinds of livers and to establish a normal database. Then, the probe is driven manually, evaluating the effective Young’s modulus too, and compared with the database finally.
From the results, porcine livers from normal and frozen ones can be identified successfully. And the apparent Young’s modulus getting from manual experiments (4,040±656Pa) is about 1.5 folds of these obtained from MTS experiments (1,758±574Pa). We suppose that it is not easy to control the probe by hand, and it causes the probe vibrating and indenting too fast. But for the coefficient of variation, the result of manual experiments is 16% and the result of MTS experiments is 33%. From this statistics, we think that it is feasible to quantitate the stiffness measured by the ultrasound indentation device driven by hand, but it maybe need more experiment samples to verify the results.

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