Biomedical subjects
Publications and source records attributed to I M Lebedenko.
The paper discusses the criteria of quantitative presentation of data on individual sensitivities and the body's vital systems potential used in treatment of cancer patients. An index is suggested to assess damage done to a system using an "automated classifier".
The effect of therapy of malignancies is at present monitored by X-ray procedures on the basis of the dynamics of the size of lesion. Since such approach fails to provide data on the structure of lesion changes and response to treatment, it is suggested that structural changes in cells of exposed tissues can by monitored by using densitometric data obtained from mammograms and (computed) tomograms, to assess density changes in tumor and adjacent normal tissues. Recovery involves certain systemic changes which can be identified using certain peripheral blood indices; the latter are evaluated using non-statistical applications of the theory of pattern recognition and cluster analysis.
Human peripheral blood values are used to define an effective dose at X-ray study. Processing is made on a technical unit comprising a blood analyzer and a computer supplied by a so-called automatic classifying system. The program is based on the recognition of images with nonstatistical assessment. A dose-effect could be first plotted in the range of effective single radiation doses of 0.8-25 mZv.
The accuracy of delivering the dose of radiation during the therapy is determined by many factors. Its enhancement requires substantial material costs. All the requirements for enhancing the accuracy are shown to be outrageous as the proportion of negative results of treatment virtually does not vary with the dosimetric and technical equipping of radiation therapy. This must alter its technical equipping policy without increasing the requirements for the accuracy of dosimetric measurements.
While processing blood values by an automatic classifying system, human beings can be divided into healthy (normal) and unhealthy (ill) persons. In so doing, one can evaluate the status of the body's individual systems (gastrointestinal tract, respiratory organs, locomotor apparatus, heart and vessels, urinary, endocrine, hemopoietic, and female genital organs, the central nervous system), which allows a physician to find a source of poor health from the very onset of disease.
Potentialities of analyzing the health condition of human organism and of its separate systems, i.e. digestive, respiratory, cardiovascular, etc., by the peripheral-blood parameters and with the help of the suggested AKS-ENOFIT analytical system are demonstrated in the paper.
The paper considers the ways of quantitative assessment of changes occurring in the density and size of a tumorous focus during its treatment (radiation, chemical and hormonal therapies). They are based on scanning densitometric techniques by identifying quantitative integral and differential parameters. The parameters are used to assess tissue alterations by applying computerized tomography. The investigations into the impact of radiation and chemotherapy on tumor tissue in breast and lung cancers have indicated that scanning densitometry and computerized tomography may be used to evaluate therapeutical effects.
The main requirement for the dosimetric support of radiation therapy for cancer disease is the necessity of keeping the high accuracy of dosimetric planning of radiation therapy. This dosimetric planning involves a number of components including the measurement of the supporting dose, the establishment of a correct orientation of a primary beam, the receipt of accurate data on the distribution of organs and tissues in the radiation area. In fact, in all the above components there are errors in the estimation of the basic values, which totally determine the total error in the dosimetric planning of radiation therapy. The paper analyzes the constituents of the errors and show their requirements to be met at the present stage of dosimetric works.
The paper outlines some possibilities of evaluating the status of tissues with a software package in order to judge the efficiency of conservative treatment. The results are substantiated on the basis of clinical and experimental findings.
The paper proposes a procedure for processing computed tomograms, which records changes in the density and size of the tissue portion exposed to radiation within the preset cross section of layers. Examples of management of 4 patients with various tumorous processes on radiation therapy are presented. The procedure of computed diagnostic processing of computed tomograms gives rather new quantitative information on the changes occurring in the pathological focus and its adjacent healthy tissues, which may lead to the efficiency of radiation therapy.
Computed tomography assesses the linear coefficient of X-ray radiation decrease in the tissue and hence determines changes in its density thus allowing one to control the destruction of tumor cells and tissues during treatment. The paper proposes a procedure for determining the sizes and density of a tumor along the chosen linear direction crossing the image of a pathological focus. The whole procedure is performed by the special computer programme "Diaglmag". The equations that characterize the dynamics of using the parameters used before, during, and after treatment are presented. Baseline information on the optic image densities on a computer tomogram is obtained with a graphic scanner. The examples presented in the paper show it feasible to solve a difficult task to determine the effect of treatment. This enables a treatment regimen to be corrected in time or modified.