Volumetric imaging of dynamic processes with microscopic resolution holds a huge potential in biomedical research and clinical diagnosis. Using supercontinuum light sources and high numerical aperture (NA) objectives, optical coherence tomography (OCT) achieves microscopic resolution and is well suited for imaging cellular and subcellular structures of biological tissues. Currently, the imaging speed of microscopic OCT (mOCT) is limited by the line-scan rate of the spectrometer camera and ranges from 30 to 250 kHz. This is not fast enough for volumetric imaging of dynamic processes in vivo and limits endoscopic application. Using a novel CMOS camera, we demonstrate fast 3-dimensional OCT imaging with 600,000 A-scans/s at 1.8 µm axial and 1.1 µm lateral resolution. The improved speed is used for imaging of ciliary motion and particle transport in ex vivo mouse trachea. Furthermore, we demonstrate dynamic contrast OCT by evaluating the recorded volumes rather than en face planes or B-scans. High-speed volumetric mOCT will enable the correction of global tissue motion and is a prerequisite for applying dynamic contrast mOCT in vivo. With further increase in imaging speed and integration in flexible endoscopes, volumetric mOCT may be used to complement or partly replace biopsies.

中文翻译：

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600 kHz 显微光学相干断层扫描 (mOCT)，用于 4D 体积成像和动态对比度

具有微观分辨率的动态过程的体积成像在生物医学研究和临床诊断中具有巨大的潜力。使用超连续光源和高数值孔径 (NA) 物镜，光学相干断层扫描 (OCT) 实现了微观分辨率，非常适合对生物组织的细胞和亚细胞结构进行成像。目前，显微 OCT (mOCT) 的成像速度受光谱仪相机的线扫描速率限制，范围从 30 到 250 kHz。这对于体内动态过程的体积成像还不够快并限制内窥镜应用。使用新型 CMOS 相机，我们展示了具有 600,000 A 扫描/秒、1.8 µm 轴向分辨率和 1.1 µm 横向分辨率的快速 3 维 OCT 成像。改进的速度用于对离体小鼠气管中的纤毛运动和粒子传输进行成像。此外，我们通过评估记录的体积而不是正面平面或 B 扫描来展示动态对比度 OCT。高速体积 mOCT 将能够校正全局组织运动，并且是在体内应用动态对比度 mOCT 的先决条件。随着成像速度的进一步提高和柔性内窥镜的集成，体积 mOCT 可用于补充或部分替代活检。