Few-sensory microwave photonic address measuring system for esophageal manometry

In the modern development of high-resolution manometry, the catheter and its elements are used at various levels of examination and treatment of the patient, both in operative and long-term follow-up systems. Therefore, the approach to the catheter as an information-measuring system that solves the problem of reproducible measurements of the spectral characteristics of each sensor in low-sensor or multi-sensor topologies comes to the fore. Moreover, due to well-known advantages, the use of fiber-optic Bragg gratings in catheters also comes to the fore. The paper presents the results of a study of the optomechanics of narrow-band classical fiber-optic Bragg gratings with a large mode coupling coefficient and spectrally addressed information recorded in them by various methods by introducing two symmetrical π-phase shifts into their structure. An analysis is made of the propagation of broadband laser radiation through spectrally addressable fiber-optic Bragg gratings in few-sensor applications. A theoretical justification is given of methods for measuring pressure and temperature, including to compensate for the effect of temperature in manometry. The technique of microwave photonic measurement conversion of pressure in the esophagus in the area of the upper and lower sphincters and the determination of its main methodological errors are given.