Reva S. Computerized system of monitoring, diagnostics and control of X-ray parameters

The thesis is devoted to the development of mathematical models and methods of reducing the dose of X-ray irradiation based on computerized system of control, diagnostics and monitoring. The purpose of the thesis is to reduce the dose of X-ray irradiation by usage of specialized computerized system of monitoring, diagnostics and control. The existing methods of irradiation dose reduction were analyzed during the X-ray diagnostic research. Index for estimation of X-ray irradiation dose by changing the supply voltage form by introducing computerized methods of control of X-ray radiation parameters has been selected and justified. For the first time the mathematical model of computerized control of X-ray diagnostic research has been suggested. The suggested model differs from the existing ones by being based on experimental dependence of X-ray receiver reaction. Results of experimental researches which were put as basement for mathematical model are provided. Results of the analysis of influence of supply voltage form on irradiation dose, which was taken with usage of created mathematical model, is also provided. Method of computerized numeric control of emitter’s load by increasing the speed of data processing based on usage of integer calculation procedures, which gives an opportunity to ensure the regular mode of emitter, has also been improved. Numeric modelling method and an algorithmic model built based on it allowed to reduce calculation load on CPU significantly, so it became possible to join function of emitter’s state control and function of X-ray diagnostic research execution process control in a single CPU. Method of monitoring, diagnostics and control of X-ray diagnostics complex was improved by more accurate calculation of exposure parameters. This was achieved by development and utilization of specialized controller, which allows to improve repeatability of the exposure dose and reduce the patient’s X-ray irradiation dose. Methods of monitoring, diagnostics and control of the computerized X-ray diagnostic research execution process that have been developed and improved in the thesis together with the created algorithmic models represent scientific and methodological basis for practical creation of specialized controller for controlling X-ray diagnostic complex. Architecture of the created specialized controller and software structure are provided. The X-ray irradiation dose was reduced: – not less than 10% - for accelerating voltage 120 kV; – more than 50% - for accelerating voltage 40 kV; – around 17% - for the most frequently used parameters. Developed methods of software control of X-ray diagnostics complex could be used for creation of new perspective X-ray diagnostics equipment, as they could be configured for work with other power supply network parameters and other modern execution devices. Results of the scientific research of the thesis are introduced on Ukrainian industrial enterprises, which manufacture medical X-ray devices and complexes and accessories for them.