RU2308888C1 - Stabilograph device - Google Patents

Abstract

FIELD: medical engineering.

SUBSTANCE: device has transducer mounted on examinee body and unit for recording transducer signal. The device also has display unit with target mounted above the examinee. Laser radiation source is used as the transducer. Video camera electrically connected to video signal transformer that is connected to computer, is applied as recorder.

EFFECT: wide range of functional applications in studying equilibrium support function.

1 dwg

Description

The invention relates to medicine, to medical devices for assessing the equilibrium function of a person, and can be used to determine the equilibrium function in physiology, otorhinolaryngology, neurology, neurosurgery.

A device for stabilography is known - a stabilograph (US Pat. RU No. 2020869), which includes a platform consisting of two parts, motionless, mounted on the floor and connected through it with sensors moving upper, which becomes the subject. The electrical signal from the sensors is converted into a digital code and analyzed by a computer. However, the known method of stabilization has significant disadvantages

- insufficient measurement accuracy, which is due to: a) incorrect determination of the equilibrium function - the latter is determined by installing the test on a platform moving relative to the ground; b) the accuracy of the study is limited by the length of the vector drawn from the center of gravity of the test to the platform, that is, a length of not more than 1 m, which requires the use of high-precision sensors;

- the complexity of the device platform with recording sensors and, as a consequence, the high price.

Studies using piezoelectric accelerometers — a method for determining the stability of a person’s vertical posture (US Pat. RU No. 20166546), make it possible to detect changes in the position of a person’s body in space with sufficient accuracy by measuring the acceleration of movement, but are of little use in studying the statics of the human body.

There is also a way to register the position of a person’s head in space, based on the effect of gravity on metal balls rolling on a curved graduated bottom of a sensor mounted on the subject’s head (copyright certificate SU 1814876). However, this method is associated with significant difficulties in setting the exact initial position of the sensor, its insufficient accuracy.

In addition, there is a device for the chemical registration of the integral motor activity of a person (US Pat. SU No. 1680074), based on a change in the concentration of ions in the water washing the sodium chloride crystal installed in an airtight sensor.

Closest to the proposed is a device for converting the movement of the human head into an electrical signal (US Pat. SU No. 1607775), in which the position of the head and body of the subject in space is determined by registering the position of the electromagnetic sensor mounted on the subject. This device has a fairly high degree of accuracy and versatility, since the sensor can be fixed on various parts of the body, which can significantly expand the study of the equilibrium function. However, this device has a significant drawback associated with the complexity of the device of this equipment, which complicates its operation, as well as the danger of exposure to electromagnetic radiation on the studied.

We are the first to propose a stabilograph device including a laser source with a mounting device on the subject, a flat dark screen with a target fixed in a horizontal plane above the center of the patient’s installation area, a video camera that records the movement of the light spot across the screen, a video to digital converter, a computer with an analysis program received images.

The device shown in the drawing, where

1 - a source of laser radiation,

2 - mounting device on the subject,

3 - examined

4 - a dark screen with a target,

5 - video camera

6 - video signal converter,

7 - a computer with a program for analyzing received frames,

8 - area of the subject.

The deviation of the subject from the vertical axis is measured as follows: the laser radiation emitted by the laser 1, which is mounted on the subject 3 using a special mounting device 2, lands on a dark screen with a target 4, which is mounted above the subject area 8 so that when installed examined 3 in this area, the laser beam hits the center of the target on a dark screen 4. Video camera 5 captures the light signal from the screen. The resulting images are converted to digital form using the video signal converter 6, they are also converted to a black and white image and recorded by computer 7. The analysis program for received frames running on computer 7 performs frame-by-frame image analysis. To do this, search algorithms for the brightest spot on a black-and-white image are used: median image filtering, which allows to smooth out fine details of the image, and then threshold binarization of the picture, followed by calculation of the position of the most prominent points remaining in the picture. The frame-by-frame analysis of the obtained video makes it possible, therefore, to judge the movements in space of a mathematical point, which is the projection of the laser beam (and therefore the subject) on the plane of the dark screen with the target. Movements are recorded relative to the center of the target.

As can be seen from the above, the resolution of the device depends mainly on the distance between the laser and the dark screen with the target, the device does not contain a moving platform, which makes it possible to study the equilibrium function in natural conditions, does not contain expensive high-precision sensors, is simple to execute and harmless to researched.

Claims (1)

A stabilizer containing a sensor mounted on the subject’s body, a sensor signal recorder, characterized in that it further comprises a target screen mounted above the subject, the sensor is a laser radiation source, and the recorder is a video camera electrically connected to a video signal converter that is connected to a computer .