Hemodynamics is a critical factor for healthy embryonic and fetal development, and when altered, could result in congenital heart defects (CHD), the most common birth defect in the newborns. The fluid mechanical forces in the blood flow during early cardiac development could influence overall morphogenesis of cardiovascular system. Though near-infrared light (NIR) point-scan OCT has been used to quantitatively assess the hemodynamics in the embryo, high speed visualization of the developing chicken embryo is still lacking. Here, we developed a line-scanning NIR OCT for high speed visualization of chicken embryo hemodynamics, which dramatically improved the overall imaging throughput and also lowered the threshold of maximal exposure limit for the power delivered to the samples. The noise performance of the supercontinuum light source with up to 200 MHz pulse repetition rate, will be characterized across different pulse repetition rates, camera exposure time, and wavelengths. An improved spectrometer employing a 1200 lpmm reflective grating, Zeiss Interlock® lenses and a two-dimensional high speed CMOS camera was built to optimize the maximal sensitivity and sensitivity rolloff. Furthermore, a phase scanning mechanism at the reference arm will also be implemented to remove image artifacts and double the imaging range. The effective performance of the line-scan OCT system in term of maximal sensitivity, imaging speed, and contrast will be assessed by imaging developing heart in chicken embryo. The structural and functional information of dynamic cardiac tissue deformation and blood flow in ultrahigh spatiotemporal resolution will further enhance our understanding of the roles of hemodynamics in embryonic development.
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