在体全眼微血流超声超分辨成像

多类眼科疾病的早期阶段一般伴有血管的形态学和血流动力学改变，因此，全眼微血管评估对眼科疾病的综合诊断具有重要作用。由于光学成像技术的穿透深度有限，特别是在介质透光率低的情况下，现有的光学成像技术难以对整个眼睛的微血管进行可视化。为此，该文开发了一种超声超分辨成像技术，可以微米级分辨率可视化全眼三维微血管系统。首先，用中心频率为10 MHz的线性阵列快速采集多帧序列；其次，经过微泡信号提取，中心点定位，追踪和中心点叠加得到一个剖面的超分辨率图像；最后，将机械扫描的所有剖面重建为兔全眼三维超分辨率微血管图像。实验结果证明，超声定位显微镜可以显示整个眼睛的微血管系统，这对眼科疾病的早期诊断具有重要意义。

In Vivo Whole Eye Microvasculature Imaging with Ultrasound Localization Microscopy

The early stage of many ophthalmic diseases is usually accompanied by morphological and hemodynamic changes of microvessles. Thus, evaluation of the whole eye microvessels plays an important role in the comprehensive diagnosis of ophthalmic diseases. Due to the limited penetration depth of optical imaging techniques, especially in the case of low transmittance of the medium, it is difficult for existing optical imaging techniques to visualize the microvessels of the entire eye. For this purpose, this paper developed an ultrasound super-resolution imaging technique that can visualize the whole eye three-dimensional microvascular system with micron resolution. Specifically, a linear array with a central frequency of 10 MHz was used to rapidly acquire multi-frame sequences, and then a super-resolution image of a slice was obtained through microbubble signal extraction, localization, tracking and center point superposition. All the acquired slices were reconstructed into three-dimensional full-eye super-resolution microvascular images. In vivo experiment demonstrates that ultrasound localization microscopy (ULM) can visualize the microvascular system of the entire eye, which is important for early diagnosis of ophthalmic diseases.