The results of an experimental study of the effect of vibrational motion of human skeletal muscles on the intensity fluctuating spectrum of the dynamic speckle field scattered by the skin are reported. It has been found by experiment that the area under the spectral curve of the speckle-optical myogram increases in proportion to the applied isotonic load until it reaches 80% of the maximum effort of the patient's brachial biceps. Further increase in isotonic load up to the maximum effort leads to a decrease in the vibrational activity of the muscle. Comparative analysis with electromyographic data has shown that traditional method fail to register this change.
Results are presented of the study of the cutaneous blood flow in patients with neurological manifestations of lumbar osteochondrosis with the help of a laser specklometer developed by the present authors. Comparative analyses of the present data with the results of IR examination and dermatothermometry has shown a great informative value of speckle-optical indices. Dynamic of the cutaneous blood flow in patients corresponded to the change in the high-frequency fluctuations spectra. In the zones of prevailing innervation of the affected radix a decrease in the average frequency of the spectrogram was observed, which reflects a decrease in the cutaneous blood flow intensity in this region.
The speckle-optical methods and the methods of electroneuromyography were used to study the myotonus, the contractional activity of leg muscles and the neuromotor system functional state in intact rabbits and 3 months after the sciatic nerve (SN) neurorrhaphy in conditions of intravenous laser irradiation of blood (ILIB). The blood of animals was exposed to laser radiation with the help of a quartz-polymeric light guide, which has been inserted into the earvein the next day after SN stitching. The radiation power at the light guide output was 2-2.5 mW. Two courses of treatment with a two-week interval have been conducted. It has been established from the speckle-optical study data that ILIB increases the contractional activity of skeletal muscles in animals. The ILIB-therapy after the SN neurorrhaphy normalizes the latent period of M-response and neural cation potential. A tendancy has been revealed to an increase in impulse conduction velocity in motor nerve fibers and in maximal amplitude of the neural action potential. Thus, the ILIB-therapy after SN trauma improves the neuromotor system functional state in experimental animals in the early reinnervation period.
It is found that in rabbits with the injured sciatic nerve irradiation of blood with low-intensity laser radiation stimulates the mechanism of hemoglobin and thrombocyte formation. Normalization of the lymphocytic composition in blood of the animals with the injured nerve shows that it is possible to prevent development of the process of lymphocytopenia. Changes in the albumins/globulins ratio, the stimulating effect of same biochemical parameters and increase of the hemopoiesis in blood of the animals with the damaged peripheral nerve can probably be considered as evidence of the positive effect of intravenous irradiation of blood with low-intensity laser irradiation on living organisms.
The results are presented of the investigation of the tonic state of muscles of normal and sick subjects by using a laser specklometer whose principle of operation is based on speckle-optical measurements of state of the human skin.
The skin microhaemodynamics and the tonic state of muscles, which provide myohypertonus in patients with radicular and reflex syndromes of lumbar osteohondrosis at moderate and pronounced musculotonic manifestations, have been studied with the help of a laser specklometer whose principle of operation is based on speckle-optical measurements of states of the human skin. When investigating the skin in these patients, asymmetry of speckle-optical indices has been revealed on the sick and the normal limbs, which was more pronounced in zones of the affected root primary innervation. The speckle-optical studies have revealed asymmetry of the vibrational properties of paravertebral muscles in patients at rest and in various postural reactions.
The results are presented on investigations to determine the optimum and most sensitive to a change in the surface blood flow informative parameters of the spectrum of the dynamic speckle-field formed by the laser radiation scattered from the skin surface. It has been found that along with the value of change in the ratio of the spectral power density at high and low frequencies, the medium frequency of the spectrum, the spectrum asymmetry about the medium frequency and the ratio of the medium frequency to asymmetry strongly depend on the functional state of the skin and, consequently, on the state of microhaemodynamics in a given portion of the skin. Maps of the distribution of micro-circulations in the investigated portion of the skin are given.
We consider laser radiation scattering by the diffuse skin surface. The skeletal human muscle transmitting its vibrations to the skin is thought of as a system of vibrating strings with a variable length.
In the present paper the possibility of determining a longitudinal displacement of an object based on the dynamic speckle effect is analyzed. That the sensitivity of three different methods differs in mutual displacement of an illuminator, diffuser, and photomultiplier is substantiated theoretically and compared experimentally.
We present the results of numerical calculations, the experimental data of studying the fluctuation spectra of speckle-field intensity at longitudinal vibration of diffuse objects. A method has been developed for determining the diffuser vibration amplitude by measuring the amplitude ratios of the first two harmonics of the spectrum.
A new method of determining the surface shape of various objects including diffusely reflecting ones is proposed. The method relies on the use of polarization measurements. As a result of the application of this method, the total (resulting) object wave at each point of the reconstructed image turns out to be rotated by an angle whose value is proportional to the relief height at a given point and the direction of the angle of rotation determines the direction of the relief change. This method permits determining not only the value, but also the sign of the relief height; it also makes it possible to increase the resolution and accuracy of measurements.
A laser microhaematomyograph designed for measuring the tonic state of muscles and surface blood flow is proposed. It can be used to investigate the biomechanical characteristics of skeletal muscles and microhaematodynamics of human skin with the purpose of diagnosing diseases of the peripheral nervous system and other systems and organs.
A holographic method of determining the refractive index of liquid and gaseous media by optical computing is proposed. In the cell, in which the reference and investigated media are placed sequentially, there is an object with the known shape of the diffusely reflecting surface. As a result of the two-exposure hologram reconstruction, an interference pattern containing information about the difference of the refractive indices of the reference and investigated media is formed.
We propose a new holographic method for investigating liquid and gas media which permits determining the absolute value of the difference of the refractive indices of the reference medium and of the medium under study by one interferogram. The light wave passing sequentially through the reference medium and the medium under study is reflected from the object with the known form of the diffusely reflecting surface. As a result of reconstruction of the two-exposure hologram obtained, as interference pattern is formed, the spatial frequencies are proportional to the difference of the refractive indices of the reference medium and the medium under study.
The present paper deals with the problems of increasing the accuracy of holographic measurements and information. To solve these problems, we suggest the use of polarization methods. The proposed approach permits performing measurements of angles instead of distances in investigating all objects, including the diffusely reflecting ones. This solves the problem of the phase difference sign the problem of increasing the accuracy of measurement. With the aid of this approach we can determine the values and directions of displacements of the points of objects, study complicated reliefs of surfaces with the determination of convexities and concavities investigate the phase media, etc.
Studies have been made of the spectral properties of radiation scattered by the human skin in vivo and of the human blood preparation at different degrees of oxygenation. It has been found that the difference of the amplitudes of the characteristic local extrema present in both the reflection spectra of man in vivo and in the reflection spectrum of the blood preparation is considerably dependent on the degree of blood oxygenation. The results obtained have enabled us to develop a contactless noninvasive method of quantitative estimation of oxyhemoglobin concentrations in the human skin blood flow in vivo.
On the basis of the investigations of the interference field spatial structure methods of optical analog calculations are proposed: differentiation of the functions of three variables, calculation of gradients, linear integrals of vector functions, and curvilinear integrals.
We propose a method for analyzing interferograms which relies on optical spatial filtering. This method permits performing the necessary mathematical operations on the original hologram by means of optical analog calculations. As a result, one can quickly obtain information about the parameters under study in the form of two-dimensional intensity distribution.
The probability density function of detection of a speckle of a fixed size in the classic pattern of a fully developed random field is studied. The notion of spatial speckle size is defined. The results obtained for the one- and two-dimensional case and the possibility of practical application of spatial speckle-field statistics are discussed.
A new multisource contouring method is presented. Holographic setup for recording uses single-beam reflection holography. Between exposures the system of object and holographic plate is rotated at a small angle (Delta) i, and an M-fold exposed hologram of the object is recorded on the same plate. After development of the plate contour fringes are generated on a reconstructed object image by multipath interference. It is possible to rotate a source of irradiation or illuminate the object through the plate simultaneously by M collimated beams instead of rotation of object-plate system. The obtained contour fringes have less FWHM in M/2 times than in the two-source contouring method.
In this paper a theory of a new holographic contouring method based on application of absorption medium is proposed, allowing definition of absolute surface relief.
In the present paper, a system for determining longitudinal displacement of an object is described. In this system the laser radiation is modulated by a rotating diffuser and it creates a dynamic specklefield whose intensity is analyzed by a low-frequency spectrum analyzer. A change in the geometrical parameters of the system due to varying the distance between the radiating head fixed on the object and the receiving unit with a diffuser changes the intensity fluctuation spectrum, which permits determining the displacement. The system is simple in design.
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