Dong Zhenyu, Mahler Simon, Readhead Carol, Chen Xi, Dickson Maya, Bronner Marianne, Yang Changhuei
Department of Electrical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Biomed Opt Express. 2024 Jul 9;15(8):4605-4624. doi: 10.1364/BOE.530366. eCollection 2024 Aug 1.
Imaging blood vessels in early-stage avian embryos has a wide range of practical applications for developmental biology studies, drug and vaccine testing, and early sex determination. Optical imaging, such as brightfield transmission imaging, offers a compelling solution due to its safe non-ionizing radiation, and operational benefits. However, it comes with challenges, such as eggshell opacity and light scattering. To address these, we have revisited an approach based on laser speckle contrast imaging (LSCI) and demonstrated a high-quality, comprehensive, and non-invasive visualization of blood vessels in few-days-old chicken eggs, with blood vessels as small as 100 µm in diameter (with LSCI profile full-width-at-half-maximum of 275 µm). We present its non-invasive use for monitoring blood flow, measuring the embryo's heartbeat, and determining the embryo's developmental stages using machine learning with 85% accuracy from stage HH15 to HH22. This method can potentially be used for non-invasive longitudinal studies of cardiovascular development and angiogenesis, as well as egg screening for the poultry industry.
对早期鸟类胚胎中的血管进行成像，在发育生物学研究、药物和疫苗测试以及早期性别鉴定等方面有着广泛的实际应用。光学成像，如明场透射成像，因其安全的非电离辐射和操作优势而提供了一个有吸引力的解决方案。然而，它也面临一些挑战，如蛋壳不透明和光散射。为了解决这些问题，我们重新审视了一种基于激光散斑对比成像（LSCI）的方法，并展示了对几天大的鸡蛋中的血管进行高质量、全面且非侵入性的可视化，其中血管直径小至100 µm（LSCI轮廓半高宽为275 µm）。我们展示了其在监测血流、测量胚胎心跳以及使用机器学习从HH15期到HH22期以85%的准确率确定胚胎发育阶段方面的非侵入性应用。这种方法有可能用于心血管发育和血管生成的非侵入性纵向研究，以及家禽业的鸡蛋筛选。
