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Dissertation
The purpose of my dissertation is to engineer the specialized computer system for definition of mineral density of an osteal tissue on a x-ray film.
The analysis of mineral metabolism in an organism attracts in itself attention of the broad audience of the specialists because a mineral salts take part in a regulation of major functional processes.
X-rays, inpouring through a living tissue, in our case the bone, on 95 % lingers over by phosphate of calcium, and bones are contained 98 % of the indicated chemical combination. Therefore, the degree of a photographic density of a x-ray film is in inverse relationship from mineral saturation of an osteal tissue.
At fulfilment of a x-ray film near to an investigated part of an atomy on the cassette places the measurement standard. As a result of it, on a roentgenogram near to the image of bones the image of the measurement standard receives.
Figure 1. X-ray graph of man’s hand and the measurement standard
After photo processing of a x-ray film with the help of the photometer or densitometer the absorbency of the image of investigated segment of a bone is determined and it is compared to similar absorbency of the image of the graduated measurement standard, which one demonstrates density of investigated object. The relation of obtained density to depth of a bone allows to judge density of a bone, that is its mineral density.
Usage of the measurement standard from aluminium is conditioned by that the aluminium has a homogeneous structural structure (bone there is no even crystalline frame).
The parsed segment of the image of object is compared on brightness to most close on brightness by segments of the measurement standard. Beforehand it is known, to what segment of the measurement standard there corresponds what mineral density. Simultaneous "photography" of object and measurement standard allows to bypass such problem, that object and measurement standard will be embodied with miscellaneous errors.
Input data of designed SCS are the digitized roentgenograms of any segment reference - propulsion apparatus of a men .
Output data of designed SCS - value mean normalized optical density of the image of investigated segments of a bone.
Designed SCS will decide following problems:
1. Primary processing of the digitized image with the purpose of improvement of its picture quality (deleting of artefacts, filtration etc.).
2. Recognition of the image of object (bones).
3. Recognition of the image of the measurement standard.
4. Definition of mean brightness of a piece of the image of object, discharged by the user .
5. Confrontation of mean brightness of a piece of the image of object to picture level of a definite step of the measurement standard.
Now in medical entities the intravital diagnostic of a condition of an osteal tissue from the point of view of mineral density implements by not computer method - reference linear X-ray densitometry(photometry). Absorbency of the image on X-ray film determine with a microphotometer or densitometer, that is devices intended for other purposes and adapted to the working conditions. Such devices founded on application of composite expensive optical systems, which one furthermore are be cumbersome. All this in the sum with some intellectual obsolescence of not computer methods of diagnostic causes a urgency of the given problem.
Essential advantage of designed SCS is the absence of necessity of acquisition by medical entity of a plenty of the composite and expensive equipment. There is enough of scanners for digitization of x-ray films.
Field of application designed SCS - any medical entity or its subdivision, which specializing on traumatology, orthopedics, and which also executing diagnostic of a condition of mineral metabolism (level of osmotic pressure, realization of excitations in a nervous system, automatism of a cardiac muscle etc.) in an organism of the men.
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