Blood flow is essential for maintaining normal physiological functions of the human body.Endoscopic laser speckle contrast imaging(LSCI)can achieve rapid,high-resolution,label-free,and long-term blood flow perfusion v...Blood flow is essential for maintaining normal physiological functions of the human body.Endoscopic laser speckle contrast imaging(LSCI)can achieve rapid,high-resolution,label-free,and long-term blood flow perfusion velocity monitoring in minimally invasive surgery.However,conventional endoscopic LSCI uses a lowcoherence laser illumination scheme,leading to restricted angles of illumination,compromised laser coherence,uneven laser illumination distribution,and low coupling efficiency,all of which degrade the quality of LSCI in the endoscope.In this paper,we propose that conical fiber(CF)-coupled high-coherence laser can be used to achieve large-angle,high-coherence,high-uniformity,and high coupling efficiency laser illumination in the endoscope.Additionally,we establish an effective model for calculating the divergence angle of CFs.Through phantom and animal experiments,we reveal that laser illumination based on CF markedly enhances endoscopic LSCI performance.This technology broadens the imaging field of view,enhances the signal-to-noise ratio,enables more sensitive detection of minute blood flow changes,expands the detectable flow range,and improves signal-to-background ratio of endoscopic LSCI.Our findings suggest that CF-based laser illumination stands as a highly promising advancement in endoscopic LSCI.展开更多
基金National Key Research and Development Program of China(2021YFC2400102)National Natural Science Foundation of China(62275095,82261138559,62305125,61890951,61890950)+2 种基金Hainan University Research Startup Fund(KYQD(ZR)20072,KYQD(ZR)22074)Chinese Academy of Medical Sciences Initiative for Innovative Medicine(2019-I2M-5-014)Innovation Fund of WNLO。
文摘Blood flow is essential for maintaining normal physiological functions of the human body.Endoscopic laser speckle contrast imaging(LSCI)can achieve rapid,high-resolution,label-free,and long-term blood flow perfusion velocity monitoring in minimally invasive surgery.However,conventional endoscopic LSCI uses a lowcoherence laser illumination scheme,leading to restricted angles of illumination,compromised laser coherence,uneven laser illumination distribution,and low coupling efficiency,all of which degrade the quality of LSCI in the endoscope.In this paper,we propose that conical fiber(CF)-coupled high-coherence laser can be used to achieve large-angle,high-coherence,high-uniformity,and high coupling efficiency laser illumination in the endoscope.Additionally,we establish an effective model for calculating the divergence angle of CFs.Through phantom and animal experiments,we reveal that laser illumination based on CF markedly enhances endoscopic LSCI performance.This technology broadens the imaging field of view,enhances the signal-to-noise ratio,enables more sensitive detection of minute blood flow changes,expands the detectable flow range,and improves signal-to-background ratio of endoscopic LSCI.Our findings suggest that CF-based laser illumination stands as a highly promising advancement in endoscopic LSCI.
