Development of a biotechnical system for intraoperative diagnosis of perfusion and metabolic parameters of biological tissues during minimally invasive surgical interventions
Authors: Potapova E.V. 
Published: October 2024

The development of modern technologies, tendencies to reduce traumatization and extent of surgical interventions have created conditions for intensive implementation and widespread use of minimally invasive surgery (MIS). For all their advantages, MIS interventions have a number of peculiarities, primarily related to limited access to the organ. This drives the need to improve and expand the range of technologies used in MIS to provide additional diagnostic information about the functional state of biological tissues. The indications for MIS interventions are very broad, but from the pathophysiological point of view, many diseases, syndromes and conditions can be described in terms of unified disorders of perfusion and metabolic parameters of biological tissues. There is no alternative to optical diagnostic methods for the determination of perfusion and metabolic parameters of biological tissues in vivo, thus making it possible to obtain additional diagnostic information in MIS practice. In particular, diffuse reflectance spectroscopy is used to measure the absorption and scattering properties of optically inhomogeneous media, such as biological tissues, and to estimate their structural and biochemical properties. Fluorescence spectroscopy is based on the registration of the autofluorescence of biological tissues when excited by optical radiation. Most endogenous fluorophores are related to the structure or to various metabolic processes responsible for the functional state of biological tissues. The main method of studying blood microcirculation is laser Doppler flowmetry – a technology based on the analysis of laser radiation reflected from the surface layer of biological tissues. Another method for assessing perfusion disorders in clinical medicine is laser speckle contrast imaging, which is based on the registration of a random interference pattern that is formed on a camera detector when an object is illuminated by coherent laser radiation. The aim of the study is to develop a biotechnical system (BTS) for intraoperative diagnostics of perfusion and metabolic parameters of biological tissues during MIS interventions based on optical diagnostic methods, which enables surgeons to obtain additional diagnostic information about the state of operated organs and tissues in real time. To achieve this goal, the possibility of assessing perfusion and metabolic disorders of biological tissues using optical diagnostic methods was scientifically substantiated. A formalized scheme of BTS for intraoperative diagnostics of perfusion and metabolic parameters of biological tissues was developed. Fiber optic probes of different designs compatible with instruments for MIS interventions were described. An example of the implementation of intraoperative optical diagnostics in gynecology based on the developed BTS is presented. A study of changes in the perfusion and metabolic characteristics of the myometrium, myoma, and pseudocapsule during myomectomy is described. It is shown that the pseudocapsule is better supplied with blood than the myoma and the myometrium, confirming the data that this structure is a vascular capsule that surrounds and nourishes the myoma. The use of modern methods of optical diagnostics based on the analysis of the interaction of optical radiation with biological tissues, together with the integration of optical technologies into modern surgical equipment, is the next technological innovation in the era of MIS development. The proposed and described methodology of building BTS of intraoperative diagnostics of perfusion and metabolic parameters of biological tissues is the basis for creating new-generation medical systems, which provide the possibility of obtaining reliable diagnostic data in conditions of limited access to biological tissues associated with the specifics of MIS interventions and allow to improve the quality and safety of surgical care.