Is it possible to image the tissue surface directly through blood without any blood disturbance treatment?

Blood can obscure the surgeon’s view during surgery, increasing the difficulty of the procedure. To mitigate its influence, methods such as hemostatic forceps, balloon occlusion, or repeated saline flushing are commonly employed. However, these methods may lead to tissue damage and increase surgical risks. Safely and effectively minimizing the impact of blood remains a significant challenge. This work presents the possibility of directly imaging the target tissue without removing blood. The three-dimensional layered vascular model, comprising blood and the vessel wall, is established, and the Monte Carlo method is employed to simulate the photon propagation within the model. The Gaussian beam is vertically incident on the surface of model with its focus located on the interface of blood and vessel wall. To maximally improve the penetration depth, the wavelength of 1270nm is chosen, and the horizontal distance between the fiber detector and the light source is set to 0.35 cm. First, the accuracy of the model is verified by the exponential decrease of the signal detected with the thickness of the blood layer. Then the possibility of directly imaging is revealed that the light (2.5μW) reflected from the vessel wall 5mm below the blood could be successfully detected when the intensity of the incident light is 50mW. The result might pioneer a new way for clinical diagnosis.