椎弓根螺釘定位演算法及導引夾治具自動化設計流程開發

鄭哲明(Che-ming Cheng)

指導教授 ： 廖昭仰

國立中央大學/工學院/機械工程學系/碩士(2014年)

摘要

椎弓根螺釘是目前用於治療脊椎側彎或畸形的主要工具，而施行此類手術需要非常準確地將螺釘植入適當的位置，在不傷到神經及血管的情況下將螺釘穿過椎弓根植入椎骨，本論文基於積層製造技術發展出一套定位演算法及導引夾治具自動化設計流程，用以減輕醫師在手術時的工作及增加植釘的準確度。
本研究所發展的定位演算法主要概念是先將病患的電腦斷層影像由軟體建立出三維網格模型，醫師僅需輸入進釘點及椎弓根約略位置，本演算法將會自行推得椎弓根螺釘最佳進釘路徑，並計算出可植入的最大螺釘半徑、長度、進釘位置及角度。接著上述數據將傳遞給本論文發展的另一個自動化流程，用以產生椎弓根螺釘進釘導引夾治具。本夾治具與病患之患部的接觸面係由電腦斷層影像重建之三維網格模型選取得來，因此可以穩固地扣在患部，提高精確度的定位。
最後，本論文以年幼病患的頸椎及胸椎椎骨的電腦斷層影像作為例子，用以驗證本文發展之方法。

關鍵字

椎弓根螺釘 ； 術中定位 ； 積層製造 ； 電腦輔助手術 ； 導引夾治具

並列摘要

Pedicle screw is the primary tool for scoliosis or spinal deformities treatment. The treatment is to implant screws in both side’s pedicles of the vertebral body, and fixing abnormal vertebral by connected metal rod. And this process requires accurate screw implanting in the implementation of the surgery. In case of injuring the nerves and blood vessels, pedicle screws pass through the vertebral body. Physicians usually using computer navigation system to determine the position of implantation when performing operation. It is difficult using two-dimensional image to determine the three-dimensional structure of complex spine structure. Therefore, this study will use self-developed program to improved registration of the surgical procedure, and reduce the workload of physicians, increasing the accuracy of screw planting.
The developed registration program of this study will load CT images of patients by the software to create a computer model, and preoperative planning on the computer. Physicians enter only pedicle screw insertion point and approximate location, the program will generate its pedicle screw entrance path and calculate the maximum radius of implantable screw length, position and angle. Physicians also can be observed the position of the screw results calculated by program on the computer model. These data will be used to generate guide template after confirmed for physicians quickly find the pedicle screw location during surgery. By careful preoperative simulation and the assistance of guide template, spine surgery will be more efficient and safer.

參考文獻

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