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Tomosynthesis is a modern effective and informative method of low-dose X-ray diagnostics, which allows obtaining a significant number of layered images with the subsequent volumetric image reconstruction. The use of tomosynthesis provides a one-time examination of a large anatomical area without loss of the image quality and diagnostics of difficult-to-visualize pathological changes that are not detected by digital radiography. The article presents an overview of the problem of improving low-dose imaging options in the radiation diagnostics, as well as the authors own data on the use of tomosynthesis for the diagnosis of community-acquired pneumonia in children.

Clinicoroentgenological diagnosis of early breast cancer - BC (non-invasive or invasive small-sized cancers) is difficult due to the absence of any characteristic clinical symptoms and pathognomonic roentgenological signs of the malignant process. Screening of BC has shown to be one of the most successful projects for early diagnosis of malignancies, but the probability to receive false negative results using screening mammography reaches 12%, and, on the one hand, this is due to interval cancers, and on the other hand - to defects in the primary screening. Among the factors associated with the likelihood of ineffective screening of BC, the most authors highlight such as high breast density, preceding the breast biopsy for a benign process, young age, as well as the use of hormone replacement therapy. The main methods of instrumental BC diagnostics are mammography, ultrasound (US), magnetic resonance imaging (MRI) and positron emission tomography (PET). Mammography is the "gold standard" for both screening and best diagnostics, but is characterized by a high proportion of both false positive and false negative results, and this can be partially solved by the use of digital mammography with tomosynthesis (performing a series of mammography images obtained at different angles and producing the focused 3-D images). Contrast enhanced mammography allows to identify angiogenesis in the area of the predicted malignancy, but is characterized by a high radiation exposure. Breast ultrasound is characterized by low specificity of the method and the high dependence of the result of data interpretation depending on physician qualifications. MRI of the breast for screening is characterized by high sensitivity, but also high cost and high proportion of false positive results. The role of PET/computer tomography in the diagnosis of early BC remains unclear, and the informative value of research in patients with nonpalpable tumors is extremely low. The roentgenological picture of early BC is widely variable; characteristic features include the presence of clustered calcifications, lumps with jagged edges, rough multinodular lumps. However, in a significant proportion of women the only manifestation of early BC is the presence of microcalcinates. Careful analysis of the localization and the shape of microcalcinates and basic characteristics allows correctly interpret the roentgenological diagnosis and helps to choose the optimal diagnostic and treatment algorithm.

Goal of the study: to investigate the capabilities of digital tomosynthesis for monitoring of tuberculous changes in the lungs against the background of chemotherapy. Materials and methods. Results of chemotherapy efficiency monitored by X-ray in 55 respiratory tuberculosis patients were analyzed. Before treatment and in 2 months after chemotherapy start all patients had X-ray and DT with consequent analysis of the obtained data. Results. When monitoring the efficiency of drug therapy for pulmonary tuberculosis by DT some additional diagnostic data were obtained in 36,4% of cases compared to X-ray. The article describes specific features of tuberculous changes visualization of the chest with the follow-up of changes by DT; opportunities for X-ray monitoring efficiency enhancement in these patients are presented. Conclusions. DT provides more accurate evaluation of tuberculous changes in the lungs compared to X-ray, which greatly enhances understanding of the course of the disease and registration of the pulmonary disease cure.

This article describes the specific primary disorder of small pelvis organs in the female patient with no tuberculosis in her medical history. Use of this roentgen technique for genital tuberculosis detection and assessment of treatment efficacy enhances the effectiveness of diagnostic activities and allows early detection of this pathology thus reducing the risk of complications which is crucial for pregnancy planning given the young age of the patient.

The paper describes a method for simulating the X-ray path through the voxel space based on the Xiaolin Wu algorithm for vector lines rasterizing with smoothing. The proposed method is designed to obtain three-dimensional ray sums and a system matrix in the design of a medical device for tomosynthesis having limited viewing angles of the projected object. General design of the X-ray device having several modes of operation including the mode of tomosynthesis is described, its technical characteristics are given. The advantage of the method before the built-in capabilities of the MatLab software package and before the previously created algorithm without anti-aliasing for the same device is explained. The general principles of the proposed algorithm for constructing the rays path in the space of voxels are outlined, and a block diagram is shown. The results of the computational experiment in the MatLab environment for constructing the ray path through a mathematical phantom, two-dimensional and three-dimensional ray sums are shown. The concept of the system matrix necessary for the functioning of a certain class of tomographic reconstruction algorithms is explained. The urgency of the work consists in the development of tomosynthesis as a cheaper, quicker and safer method in comparison with the full tomography, while there are no ready-made software products for the intrinsic problems solution, so it becomes necessary to develop special algorithms and programs oriented to the posed problem. The scientific novelty of the work lies in the application of the two-dimensional Xiaolin’s line algorithm from the field of computer graphics to the field of radiography by expanding this algorithm to a three-dimensional version taking into account all the features of the medical device desig.

The work is devoted to description of the computer simulation procedure & the algorithm for obtaining three-dimensional ray sums basing on the Bresenham’s line algorithm in the devices for tomosynthesis, assuming limited scan angles of the object projected. The paper contains a brief historical survey on tomographic systems, an explanation of the advantage of the fan-beam scheme of data extraction over parallel scheme, and purposes of tomosynthesis development alongside with the tomography. The proposed device design is summarized, its technical characteristics are specified, and the data extraction process is described. Features of the built-in Radon transformation & fan-beam transformation functions of the MatLab software package which prevent them from being used for solving the task are revealed. A general description of the Bresenham’s line algorithm for vector lines rasterization is provided, and so is a complete block diagram of the proposed algorithm for obtaining beam sums based on it. The results of computational experiment for obtaining a set of virtual mathematical phantom projections in a MatLab environment are demonstrated. The relevance of the research lies in the development of tomosynthesis as a cheaper, faster & safer alternative to tomography in situation when the modeling of its inherent processes is difficult due to the lack of suitable ready-made software solu-tions, therefore arises the need to develop the algorithms and software for computer-aided modeling, adapted for the tasks set. The scientific novelty consists in the two-dimensional Bresenham’s line algorithm adaptation for solving tomosynthesis problems & the creation of the three-dimensional algorithm, carrying out the complete cycle of obtaining the scanning object projections in a tomosynthesis device, taking into account all the geometric features of the latter.

Со времени открытия в 1895 г рентгеновских лучей и внедрения их в общую практику стандартная рентгенография остается наиболее доступным методом обследования пациентов, в том числе с заболеваниями позвоночника. При стандартном рентгеновском исследовании позвоночного столба все анатомические структуры, расположенные на различной глубине и разном расстоянии, проецируются на рентгеновской пленке или экране в виде плоскостного изображения. С целью нивелировать данные недостатки и улучшить визуализацию были разработаны различные томографические методики. Наиболее современной и перспективной является многосрезовая линейная томография (томосинтез), при которой за один проход рентгеновской трубки получается серия срезов. Цифровую многосрезовую линейную рентгеновскую томографию в мировой практике, как правило, применяют для исследования молочных желез, легких. В статье приведены данные о различных рентгеновских видах томографии при обследовании пациентов с туберкулезным спондилитом., A standard X-ray is still the most affordable method of evaluation of patients, including those with spinal diseases since 1895 when X-rays were found and were introduced into general practice. In the standard X-ray examination of the spine and all the anatomical structures located at different depths and different distances, projected onto x-ray film or a screen in the form of planar image. In order to neutralize these drawbacks and to improve visualization, various tomographic techniques have been developed. The most modern and promising diagnostic method is a multisection linear imaging (tomosynthesis), in which a single pass X-ray tube is a series of slices. Digital X-ray tomography with multislice linear are used as a rule, in the world, for examination of breast and lungs. The article presents data on the different types of X-ray tomography in evaluation of patients with tuberculous spondylitis., Журнал “Диагностическая и интервенционная радиология”, Выпуск 4 2015, Pages 69-76