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Spectrally Extended Line Field Optical Coherence Tomography Angiography

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 نشر من قبل Si Chen
 تاريخ النشر 2021
  مجال البحث فيزياء
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Optical coherence tomography angiography (OCTA) has been established as a powerful tool for investigating vascular diseases and is expected to become a standard of care technology. However, its widespread clinical usage is hindered by technical gaps such as limited field of view (FOV), lack of quantitative flow information, and suboptimal motion correction. Here we report a new imaging platform, termed spectrally extended line field (SELF) OCTA that provides advanced solutions to the above-mentioned challenges. SELF-OCTA breaks the speed limitations and achieves two-fold gain in FOV without sacrificing signal strength through parallel image acquisition. Towards quantitative angiography, the frequency flow imaging mechanism overcomes the imaging speed bottleneck by obviating the requirement for superfluous B-scans. In addition, the frequency flow imaging mechanism facilitates OCTA-data based motion tracking with overlap between adjacent line fields. Since it can be implemented in any existing OCT device without significant hardware modification or affecting existing functions, we expect that SELF-OCTA will make non-invasive, wide field, quantitative, and low-cost angiographic imaging available to larger patient populations.



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