椎弓釘植入為脊椎手術中重要的步驟，但椎弓釘植入需要準確的位置以避免併發症的發生。近年來電腦導航手術的興起，可以增加鋼釘植入的準確度以及降低放射線的暴露。
本研究為臨床實作，是以實驗室既有的C-arm影像手術導引系統，來輔助椎弓釘植入手術。研究目的除了評估這套系統的臨床可用性之外，也希望以臨床醫師的需求為基礎來做系統改良。在將這套系統應用於病人之前，我們事先經過假骨實驗的測試，也取得人體試驗委員會的同意。
本研究在桃園醫院總共收集了十二位病人，共七十根的椎弓釘植入。術後使用電腦斷層來評估鋼釘的準確度，而根據椎弓釘破出椎莖的程度，準確度共分為ABCD四級，其中A級與B級定義為準確。經過平均一年的隨訪，結果為下：A級有52隻, B級占16隻，C級有2隻，無D級，故準確度為 97.1%。在臨床上，病人並無神經受損的併發症產生。
藉由導航系統的幫忙，我們醫師可以更準確的植入椎弓釘，並降低放射線的暴露。與電腦斷層（CT）影像導引系統比較，這套C-arm影像手術導引系統在使用上有著註冊方便，成本較低的優勢，卻也有著缺乏「橫斷面影像」的劣勢。另外，影像校正器不能適用於所有的C-arm接收端，這也是需要改進的地方。希望這研究能對改良這套系統有所貢獻，使其未來能進一步應用於脊椎側彎以及微創手術。

Pedicle screw insertion is an essential step in spinal fusion surgery. To avoid implant-related complications, precise location of pedicle screw is necessary. In recent years, the rise of using surgical navigation system improved screw accuracy and decreased radiation exposure.
This study, a clinical implementation, is based on pre-existing C-arm based image navigation system in our laboratory to assist pedicle screw insertion. The purpose of this study is not only to assess the availability of this navigation system, but also to improve it from surgeon’s point of view. Before this system is applied to the real patient, we had tested “saw bone” experiments. We also obtain the consent of Institutional Review Board (IRB).
A total of twelve patients who underwent posterior spinal surgery with total 70 pedicle screws were collected in Taoyuan general hospital. Post-operative computed tomography (CT) scan was used to assess the accuracy of pedicle screws. Accuracy is divided into four degrees, including ABCD while class A and class B is defined as accurate. After a mean follow-up of one year, the results were as following: Grade A has 52 screws, grade B accounting for 16 screws, grade C has two without grade D, so the accuracy was 97.1 %. Clinically, the patient had no complications of nerve damage.
With the help of the navigation system, we physicians can implant pedicle screws more accurately, and reduce radiation exposure. Compared with CT-based navigation system, this C-arm -based system has advantages in convenient of registration and low -cost, but it has a lack of " cross-sectional image". In addition, the C-arm Image calibrator can not be applied to all types of C-arm, which is the need to improve. I hope this research can contribute for improving the system so that it can be further applied to scoliosis surgery and minimally invasive surgery.

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