Patent RU-2770266-C2 (RU)
Inventor: Tarasov Andrej Petrovich
IPC: A61B5/1455
Filed: 2020-07-16
Granted: 2022-04-15
Abstract: FIELD: medical equipment. 
     SUBSTANCE: group of inventions relates to medicine, namely, to a sensor for an optical cerebral oximeter, a method for optical cerebral oximetry, and an apparatus for securing the sensor. Sensor includes a flexible body, a photodetector, an amplifier for the signal from the photodetector, and light sources. The light sources emit light in two different spectral ranges and are represented by two pairs. The light sources with the signal amplifier and the photodetector are arranged consecutively along the axis of the body. The ratio of the distances between the first pair of light sources, located further from the photodetector, and the photodetector, and the second pair of light sources, located closer to the photodetector, and the photodetector is therein in the range from 1.2:1 to 4:1, with a maximum distance between the first pair of light sources and the photodetector of 6 cm. The light sources in both pairs are therein placed adjacent to each other. The light sources are configured to be connected with a microprocessor. Each light source comprises one LED with a power of 100 MW. Each pair of light sources comprises one light source with a wavelength in the range of 800 to 810 nm and a second light source with a wavelength outside said range. The amplifier of the signal from the photodetector is represented by a microchip integrated directly into the body of the sensor. The apparatus for securing the sensor to the head of the patient includes a flexible strap. The strap is configured to be placed around the head of the patient. The strap consists of an elastic part. The elastic part includes a forehead part and a clasp. The forehead part is configured to be connected with at least two sensors. The clasp consists of a Velcro tape represented by fragments with micro-hooks and micro-loops, located at different ends of the elastic part. The elastic part has a length adjuster. The length of the elastic part is made adjustable so that the ratio of the length of this part to the length of the fragment with micro-loops can vary in the range from 1:1 to 2:1. The ratio of the lengths of fragments with micro-loops and micro-hooks, respectively, is therein in the range from 4:1 to 10:1. In implementation of the method, the parameters of operation of the light sources are set by a microprocessor. The microprocessor therein ensures operation of the light sources in a pulse-periodic alternating mode with a constant power of emission in a pulse without intensity modulation. The parameters of the power of emission in a pulse, pulse durations no greater than 250 ms, and pulse repetition frequency in the range from 1 to 1,000 Hz for the microprocessor are selected so that the average power of the light emitted by the light source for 1 second does not exceed 50 MW. 
     EFFECT: due to the structural features of the sensor, accuracy and reliability of measurements of the level of blood oxygenation of the brain is increased, level of noise in the received signal is reduced, possibility of repeat use of the sensor is provided. 
     6 cl, 8 dwg