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2LASER SPECKLE CONTRAST IMAGING SYSTEM FOR NEUROSURGICAL PROCEDURES
ANTON KONOVALOV, FEDOR GREBENEV, DMITRY STAVTSEV, IGOR KOZLOV, GRIGORY PIAVCHENKO, DMITRY TELYSHEV, ANDREY GALYASTOV, ANASTASIA GORINA, IGOR MEGLINSKI, SERGEY KUZNETSOV, DENIS OKISHEV, YURI PILIPENKO, SHALVA ELIAVA
Burdenko Neurosurgical Center, Moscow, Russian Federation I.M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
INTRODUCTION
In neurosurgery, accurate visualization of tissue perfusion and cerebral vessel patency is crucial for minimizing risks and achieving optimal surgical outcomes. While traditional imaging methods are effective, they often lack real-time feedback on tissue perfusion. The Laser Speckle Contrast Imaging (LSCI) system offers an innovative solution, enabling dynamic visualization of blood flow in tissues, significantly enhancing the precision and safety of surgical procedures1. The goal of this study was to develop an LSCI system for a neurosurgical microscope and to evaluate the effectiveness of the real-time LSCI method for monitoring blood flow in standard cerebrovascular surgical scenarios modeled on phantom and animal models.
MATERIALS AND METHODS
The LSCI system was developed considering the features of standard neurosurgical microscopes. The key components include a laser module emitting at a wavelength of 803 nm, a high-resolution CCD camera, and custom-developed software for image processing. The system was integrated into a Zeiss Pentero 900 microscope using specialized optical and mechanical components to ensure stability and reliability during operations (Figure 1). Experiments were conducted on phantom models simulating the optical properties of biological tissues, as well as on ex vivo tissue samples (Figure 2).. Additionally, the system was tested in real neurosurgical procedures on rat models (Figure 3), allowing for the evaluation of its clinical applicability and integration into the surgical process.
Figure 1. Integration of the LSCI System into the Neurosurgical Microscope
Figure 2: LSCI in a bifurcation vascular embolic phantom model. (A) and (B) show speckle contrast images of blood flow in a microfluidic phantom model before and after the introduction of an occlusion by air emboli (indicated by white arrows). Regions of interest (ROIs) 1, 2, 3, and 4 are marked for detailed analysis. (C) presents the time course of speckle contrast values for the ROIs, with the black arrow indicating the moment of occlusion. The decrease in speckle contrast corresponds to a reduction in blood flow, demonstrating the LSCI system's capability to dynamically monitor perfusion changes.
Figure 3: (A) Graph of measurements of relative blood flow during real-time LSCI. (B) Graph of blood flow dynamics during postprocessing of LSCI data with noise suppression from movements, with the same ROI. C—ROI at two points in the left CCA (2, 3) and the right CCA (1—control).2
RESULTS
The integration of the LSCI system into the neurosurgical microscope was successfully implemented, providing high-precision real-time blood flow images. The system demonstrated a strong correlation between speckle contrast and actual blood flow parameters, confirming its accuracy and reliability2'3
CONCLUSION
The introduction of the LSCI system into clinical practice represents a significant advancement in intraoperative imaging. The system enables neurosurgeons to rapidly assess tissue conditions, which can substantially improve surgical accuracy and patient outcomes. Future plans include continued clinical trials and technology optimization to expand its application in neurosurgery and other areas of medicine.
REFERENCES
[1] Konovalov A, Gadzhiagaev V, Grebenev F, Stavtsev D, Piavchenko G, Gerasimenko A, Telyshev D, Meglinski I, Eliava S. Laser Speckle Contrast Imaging in Neurosurgery: A Systematic Review. World Neurosurg. 2023 Mar;171:35-40. doi: 10.1016/j.wneu.2022.12.048. Epub 2022 Dec 13. PMID: 36526222.
[2] Konovalov, A., Grebenev, F., Stavtsev, D. et al. Real-time laser speckle contrast imaging for intraoperative neurovascular blood flow assessment: animal experimental study. Sci Rep 14, 1735 (2024). https://doi.org/10.1038/s41598-023-51022-2
[3] A. Sdobnov, G. Pyavchenko, A. Bykov, and I. Meglinski, "Advances in Dynamic Light Scattering Imaging of Blood Flow", Lasers & Photonics Reviews, Vol.18, No.2, 2300494 (2024)
