The effect of optical cleaning method combined with laser speckle imaging (LSI) was discussed to improve the detection depth of LSI due to high scattering characteristics of skin, which limit its clinical application. A double-layer skin tissue model embedded with a single blood vessel was established, and the Monte Carlo method was used to simulate photon propagation under the action of light-permeating agent. 808[Formula: see text]nm semiconductor and 632.8[Formula: see text]nm He–Ne lasers were selected to study the effect of optical clearing agents (OCAs) on photon deposition in tissues. Results show that the photon energy deposition density in the epidermis increases with the amount of tissue fluid replaced by OCA. Compared with glucose solution, polyethylene glycol 400 (PEG 400) and glycerol can considerably increase the average penetration depth of photons in the skin tissue, thereby raising the sampling depth of the LSI. After the action of glycerol, PEG 400, and glucose, the average photon penetration depth is increased by 51.78%, 51.06%, and 21.51% for 808nm, 68.93%, 67.94%, and 26.67% for 632.8 nm lasers, respectively. In vivo experiment by dorsal skin chamber proves that glycerol can cause a substantial decrease in blood flow rate, whereas PEG 400 can significantly improve the capability of light penetration without affecting blood velocity, which exhibits considerable potential in the monitoring of blood flow in skin tissues.

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通过局部光学清除提高激光散斑成像的采样深度：理论和体内研究

讨论了光学清洗方法结合激光散斑成像（LSI）的效果，以提高LSI的检测深度，因为皮肤的高散射特性限制了其临床应用。建立单血管嵌入的双层皮肤组织模型，采用蒙特卡罗方法模拟透光剂作用下的光子传播。选择 808[公式：见正文]nm 半导体和 632.8[公式：见正文]nm He-Ne 激光器来研究光学透明剂 (OCA) 对组织中光子沉积的影响。结果表明，表皮中的光子能量沉积密度随着被OCA取代的组织液量的增加而增加。与葡萄糖溶液相比，聚乙二醇 400 (PEG 400) 和甘油可以显着增加光子在皮肤组织中的平均穿透深度，从而提高 LSI 的采样深度。在甘油、PEG 400 和葡萄糖的作用下，808nm 激光器的平均光子穿透深度分别提高了 51.78%、51.06% 和 21.51%，632.8 nm 激光器分别提高了 68.93%、67.94% 和 26.67%。背侧皮肤室的体内实验证明，甘油可导致血流速度大幅下降，而PEG 400可在不影响血流速度的情况下显着提高光穿透能力，在监测皮肤组织血流方面具有相当大的潜力。808nm、632.8nm激光器的平均光子穿透深度分别增加了51.78%、51.06%和21.51%、68.93%、67.94%和26.67%。背侧皮肤室的体内实验证明，甘油可导致血流速度大幅下降，而PEG 400可在不影响血流速度的情况下显着提高光穿透能力，在监测皮肤组织血流方面具有相当大的潜力。808nm、632.8nm激光器的平均光子穿透深度分别增加了51.78%、51.06%和21.51%、68.93%、67.94%和26.67%。背侧皮肤室的体内实验证明，甘油可导致血流速度大幅下降，而PEG 400可在不影响血流速度的情况下显着提高光穿透能力，在监测皮肤组织血流方面具有相当大的潜力。