Study on Brain phantom and Markers in Surgical Training

水腦症好發於老人，腦脊髓液過多導致腦壓增加，嚴重可能導致昏迷、甚至死亡，而腦室腹膜引流術為神經外科最常用的治療方式，透過引流側腦室過多的腦脊髓液至腹部吸收，但其手術所需要的精準度仍需要改善，因現今醫師大多以盲穿的方式來執行手術，會發生重複穿刺的情形，同時放置引流管的位置，不一定是最佳位置，導致術後復原的狀況，可能出現引流管移位、導管堵塞...等情形。拜現今科技之賜，影像導航手術目前被廣泛應用於神經外科手術，透過術前拍攝CT斷層掃描影像，術中透過軟硬體整合之系統導航，來降低手術的失誤率，增加精準度，其中以光學式導航為最大宗，機械式較方便架設•同時，許多實習醫師因為缺乏手術經驗，在實際執行手術時，無法掌握穿刺手感，確認已經將探針置入腦室，也有先例研究擬真大腦假體來解決此問題。以及，手術系統在病人身上的定位器，是否可以重複配戴重現其精準度，使影像註冊更為快速便利，亦是現今很多手術導航系統的研究方向，而本實驗室開發之機械式導航系統，結合工業用精準的機械手臂、簡易操作之規劃軟體、可重複配戴之定位器，以及模擬真實觸感之擬真大腦假體，達到快速架設的便利效果、系統規劃精準性(規劃精度達3mm以下)，以及實習醫師透過擬真大腦假體實際練習模擬臨床的手感，及累積經驗，有效的降低腦室引流手術的失誤率，提昇整體的精準度及成功率! 此研究專注在開發適用於手術訓練之大腦假體及定位器，實習醫師若能夠先利用擬真大腦假體，執行手術的穿刺訓練，即可在進手術房前預先有經驗，而不會造成重複穿刺之錯誤，假體，分為頭殼，及內部腦組織部分，頭殼透過預先了解醫生常開刀位置，先進行鑽孔，並分上下蓋，而大腦軟組織，透過測試結蘭膠、吉利丁粉、吉利T粉，進行不同濃度混合，並進行硬度、密度、醫師嘗試穿刺測試，確認最接引大腦的機械性質的假體，達到擬真穿刺的模擬。 雖然fiducial marker的註冊十分方便，但是病人拍攝CT影像及動手術的時間並不會一致，所以需要設計可重複配戴之定位器，讓病人可以在手術時，可再次重複配戴，並重現其位置，達到註冊的便利性，此研究中針對fiducial marker、耳戴型定位器及面罩型定位器進行實驗及比較。Hydrocephalus is a disease that usually occurs in older adults. It is a condition that there is too much cerebrospinal fluid in the brain. The increase of brain pressure may cause patient faint or to death. VP-shunt is the common surgical way that treats hydrocephalus. It uses external ventricular drain to make excessive cerebrospinal fluid absorb by peritoneal. However, the accuracy of this surgery could be improved because most surgeons performed free hand, relying on the landmark of the patient face. Without image-guide surgery system’s assistance some conditions may occur, including mal-position, repeated insertions or infection. Recently, image-guide surgery is generally used in neurosurgical procedures. Before performing surgery, surgeons use CT scans to check the target. With the help of the navigation system, the occurrence of surgical error will decrease. Meanwhile, residents should be proficient in their training, so some researcher developed a simulator allows the surgeons to get a feel for texture of brain. Therefore, this research focuses on the development of the brain phantom for surgical training. The phantom includes skull, brain tissue and ventricles. The 3D-printed skull has been firstly drilled hole where surgeons usually puncture. Meanwhile, we took gellan gum, gelatin, and jelly t powder, mixing with different concentrations to make mimic brain phantom. Finally, we measure its hardness, density, to confirm which brain phantom is most similar with human brain. Developing a convenient way to conducting registration for navigation system is also an important issue. Because using a marker that can be repeated wear will make patient more comfortable during surgery. Patients don’t need to wear the marker while waiting between after taking a CT scan before having a surgery. So we also study for the ear’s marker and mask marker which can both maintain repeatability and accuracy