隨著醫療科技進步與生活型態轉變，現代人脊椎病變的案例逐年增加，而脊椎融合手術是脊椎病變患者中最常進行的手術之一，此手術目的是要連結雙節或多節脊椎骨，在脊椎骨上架上鋼柱以提供脊椎之支撐力，藉此矯正脊椎彎曲、骨節連動、脊椎支撐等問題。此手術風險較高，非常仰賴醫師的專業技巧及經驗，需要精準判斷脊椎骨位置、下竿點與入釘角度，以免傷及病患造成終身傷害。本論文建立一套手術模擬訓練系統，讓有需要或經驗不足的醫生可重複練習手術操作與判斷，以增加熟練性。手術模擬系統需要脊椎骨的三維模型，為了讓模擬更真實，我們採用實際病人資料並以最常受傷的T12、L5兩椎節為目標進行模擬。我們提出一個基於模型的半自動level set演算法用於分割骨頭以產生模型，由臨床脊椎的電腦斷層影像分割出骨頭區塊，並建成三維模型，然後由核磁共振影像分割出血管、神經等脊椎周圍軟組織並各自建成模型。我們設計了擁有力回饋的手術模擬系統，將上述模型放入三維空間中，以虛擬工具進行穿刺、入釘等手術步驟模擬，同時給予碰觸到骨頭時的觸感，與穿刺皮質骨進入海綿質骨時的差異感，以增加真實性，並以動畫方式展示釘子進入脊椎骨時的情況。手術模擬系統也可記錄手術進行過程，在需要時重播讓訓練者查看自己手術進行過程。 在手術模擬結束後可將脊椎骨顯示為半透明，並可以用任意角度觀看骨釘植入後的位置，以判斷此次手術成功與否。手術模擬系統可依照不同病人的資料新建模型，讓醫師可以練習在病情輕重不同的病例下做練習，不但可以減少傳統實體模型一次性的開銷，也可利用評估方式增加手術訓練的效率。

Due to the remarkable advance in medical technology and health science, life expectancy becomes longer years by years. In Taiwan, the life expectancy increases 2 years for men and 3 year for women from 2003 to 2013. The amount of patients with spine degeneration, spine scoliosis, and spine trauma increases stably. One of the most common spine surgeries is the spine fusion surgery. In this surgery, pedicle screws are inserted into vertebras and rods are then used to connect two or more implanted screws that can stabilize the lesion vertebra and provide better spine supports for upper body. Although spine fusion surgery is really important, it comes with high risk. The success rate of spine fusion surgery depends on the skillfulness and experiences of surgeons. This research designs and constructs a pedicle screw implantation simulating system for new surgeons to train their skills and help them become familiar with the surgery operations. For better simulating the surgical reality, we build the 3D models of bones, artery, vein, and nerves based on clinical image data. We adopt T12, L5 vertebras which are the most popular target of spine fusion surgery. We provide a semi-automatic level set algorithm to segment vertebras from CT images and some methods to segment arteries, veins, and nerves from MR images. A 3D virtual environment is built with haptic system for giving force feedback while surgery simulation. The 3D model of vertebras, arteries, veins, and nerves is merged into the virtual environment, and we can use the haptic device as the virtual operation instrument to penetrate vertebra or implant the pedicle screw. While performing surgery operations, we can get the force feedback when penetrating through the compact bone to the sponge bone. The simulation system also has the ability to record the path where the operation instruments going through, and it can be later replayed to review the operations by animations after surgery. The user can set the opacity of bone or modify the view points to see where the pedicle screw implanted and judge whether the surgery is successful. This simulation system has great reusability and efficiency because the constructed models can be used by different users repeatedly, which the conventional plastic model can only be used once in surgical training.

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