發展飛秒雷射顯微手術系統於線蟲觸覺神經之切割與神經再生之應用

Abstract

雷射在這些年來已經被用在多種醫療手術上。譬如近視及遠視雷射手術、軟組織的去除，甚至用在癌症的治療。選擇不同的功率、重複率、波長的雷射，在不同的生物材料上會產生不同的化學及物理作用。我們的實驗中選用了780nm 的飛秒雷射光切割PC12神經細胞及線蟲的觸覺神經並觀察術後現象及行為。 飛秒脈衝雷射應用在手術上有許多優點。我們是利用80MHz，功率為20mW對樣品做切割。鈦藍寶石雷射每個脈衝有較大的能量強度，平均一個脈衝有0.25nJ，也不會對樣品有其他的傷害。另外，我們使用的光源為近遠紅外光，不易散射而可深入生物材料內聚焦。因此可成功並準確地在微米尺度上對不同樣品切割，譬如膠原蛋白、細胞或是神經的樹突及軸突。 結合了兩套光學系統，我們需要藉由GFP確認線蟲神經位置並同時使用鈦藍寶石雷射光切割欲要切除神經。當聚焦處的神經被切割後，使用挑蟲器刺激線蟲運動並了解他的術後行為。因此應用飛秒雷射及此套光學系統這種非侵入式的手術會在臨床手術上有更進一步的發展。

After years of development, laser has been applied in numerous medical treatment procedures. Surgeries such as correcting near and far sightedness, dissection on soft tissue and even cancer-relate therapies are gradually being implemented. Choosing different power, repetition, wavelength of the laser, we can create multifarious chemical or physical reactions with different bio-materials. In our experiment, we use 780nm, femtosecond laser to dissect neuron cell (PC12) and the touch neuron of Caenorhabditis elegans, in order to observe the following behaviors after excising distinct cellular componentss. Femtosecond pulse laser embraces plenty of advantages in surgical purposes. The repetition rate of our laser pulse is 80-MHz, and the maximum cutting power is 20mW. Since Ti-sapphire laser provides high energy in each laser pulse, we can cut neurons by tuning pulse energy around 0.25nJ, without extensive tissue damage. In addition, we use near infrared light as source (780nm wavelength), pushing the focus deeper into biological specimens. Therefore, we can successfully execute precise surgery on the micron-sized sample such as collagen, cells or even the specific parts of neuron. Combining two optical systems, we confirm the position of C.elegans neuron by GFP, and meanwhile, use Ti-Sapphire laser to dissect the targeted neuron section . After witnessing the damage on neuron, we use a picker to motivate the exercise of C.elegans and to study its post-surgery behaviors.