小鼠在体内耳微小结构的相位对比Micro-CT研究

目的:通过相位对比Micro-CT研究小鼠在体内耳微小结构,并探讨该技术对在体内耳微小结构的显示能力。方法:成年小鼠,麻醉后处死;应用基于传播的相位对比Micro-CT扫描小鼠双侧内耳;重建CT数据,像素点大小9μm;进行图像重组,得到像素点尺寸不同的CT图像。结果:在像素点大小为9μm的CT图像上,可清晰观察耳蜗蜗轴、骨螺旋板、椭圆囊斑、球囊斑等微小结构;像素点大小为36μm的图像仍可显示以上目标结构;像素点大小为54μm的图像上,各微小结构边缘不太清晰,只可显示其轮廓;像素点大小为72μm的图像上,椭圆囊斑和球囊斑已不可见。结论:基于传播的相位对比Micro-CT对小鼠在体内耳微小结构成像具有明显优势,且在像素点尺寸不大于36μm的条件下,相位对比Micro-CT可较为清晰地显示在体小鼠内耳微小结构。 

Imaging Microstructures of Mouse Inner Ears in Situ by Phase Contrast Micro-CT

Objective: Aim of the study was to image the mouse inner ears in situ by phase contrast Micro-CT, and explore the ability of this technique to display the microstructures. Method: The experiment was performed according to our institution's guidelines on the care and use of laboratory animals. An adult mouse was anesthetized and sacrificed, followed by phase contrast Micro-CT scan for both inner ears. The CT data sets were reconstructed using the filtered back-projection (FBP) algorithm. Different pixel-size CT images, including 9 μm, 18μm, 36 μm, 54 μm and 72 μm, were obtained after image processing. Results: The CT images of 9 μm pixel size visualized clearly the microstructures of inner ears, including modiolus, osseous spiral lamina, utricular macula and saccular macula. The edge sharpness of the microstructures was decreasing when the pixel size of the images became bigger. The CT images of 18μm and 36 μm pixel size also displayed all of the microstructures. The microstructures were seen in the CT images of 54μm pixel size, but their edges were blurry. The CT images of 72 μm pixel size showed an indistinct outline only of the modiolus and osseous spiral lamina, while the outline of utricular macula and saccular macula was not observed. Conclusion: Phase contrast Micro-CT was demonstrated to have the potential to visualize the microstructures of mouse inner ears in situ.