【摘要】目的探讨PTK切削方式下，准分子激光切削视网膜制备理想感光细胞片层所需的最佳切削深度。方法以新生小牛视网膜为研究对象，白明胶作载体，液态视网膜铺片法铺片，准分子激光PTK切削方式，共切削3种深度，制备48个感光细胞片层，行光镜和电镜观察。结果用准分子激光PTK切削方式，80μm切削深度下可以获得较好的视网膜感光细胞片层，光镜和扫描电镜均显示完整的感光细胞节段、外颗粒层、外网状层以及部分残存的内颗粒层细胞，而50μm和100μm深度则分别较浅和较深。结论80μm是准分子激光PTK方式切削视网膜制备感光细胞片层的适宜切削深度。

    关键词 视网膜 准分子激光 PTK方式 感光细胞片层 80μm切削深度

    Harvesting photoreceptor cell sheets by using excimer laser with 80 micron depth of ablation

    Li Genlin,Wang Gang,Wang Jin’jin,et al.

    Ophthalmologic Center,Beijing Tongren Hospital Affiliated to Capital University of Medical Sicence,Beijing 100730.

    【Abstract】ObjectiveTo study the ideal ablation depth for harvesting sheets of photoreceptor cells from retina by using the excimer laser with PTK (phototherapeutic keratectomy,PTK) mode.MethodsRetinas from neonatal calf,and gelatin as carrier were used.The retinas were located firstly and then laid on the surface of gelatin carrier using the devised liquid-phase method.The PTK mode of excimer laser was used to ablate retinal sheet.Total 48 photoreceptor sheets were ablated with three depths and were studied by light and scanning electron microscope.ResultsWith 80 micron depth of ablation,photoreceptor cells were harvested as intact sheets from the retinas using the excimer laser.Light and scanning electron microscope demonstrated the sheets of photoreceptor cells with intact outer and inner segments,outer nuclear layer,outer plexform layer and some remained inner nuclear layers.However,50μm and 100μm were found to be either rather superficial or deeper than that of 80μm.ConclusionFor harvesting ideal intact photoreceptor cell sheets,80 micron would be the most suitable depth of ablation by using the PTK mode of excimer laser. ......