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The article presents the results of evaluation of compensation abilities of kidney based on the identification of volume of functioning renal tissue according to the single-photon emission scintigraphy (SPECT) and planar scintigraphy. The study included adult patients (65 patients with renal cell carcinoma, 32 patients with renal cysts and 20 patients without renal involvement) and pediatric patients aged 1 to 17 years (57 patients with various non-neoplastic lesions of the kidney). The following parameters were used: volume ratio of functioning tissue and the specific activities of the affected and contralateral kidneys, and the volumetric ratio of volumes estimated to the reference kidney volume depending on anthropomorphic data of patient (age and sex). It was found that the maximum compensatory renal reserve occurs in the case of reducing the volume of functioning tissue of the affected kidney and the simultaneous increase in the volume ofcontralateral kidney.

Purpose: to work-out method of the determination the volume of functioning thyroid tissue on the base of experimental investigations and to appreciate its accuracy. To analyze the clinical results of determination of the volume of the thyroid volume for different clinical groups with the use I123., Material and Methods: experimental investigations of the phantoms of different sizes were conducted, and also there were conducted the investigations of the phantoms with different diameters spheres which were inside the phantoms. On the base of conducted investigations there was suggested a method of the determination of the volume functioning thyroid tissue paying attention to the organ sizes and the microtexture of the picture. Summary error of this method with taking into consideration different factors was 7.02%. There were examined 36 patients with different kinds of thyroid diseases and patients of conditionally control group. Every patient was made planar method and SPECT with the use I123., Results: the experimental investigations showed that for the determination of the volume of functioning tissue according SPECT data it should use the variable level of cut out of the background during analyzing the data paying attention to the organ sizes. The clinical investigations pointed out that there were trustworthy differences between signs indices among different clinical groups. Some signs are specifically for cancer, adenoma, Graves' disease. The most volume of nonfunctioning thyroid tissue is at cancer patients., Conclusion: there was worked out the method of determination of volume functioning thyroid tissue according to SPECT data. On the base of the received results there were offered integral indices which can be used for differential diagnose of the thyroid diseases.

The aim of the trial was to study compensatory potential of renal parenchyma in the presence of renal cell carcinoma (RCC) and after organ-saving and radical surgical treatment as shown by one-photon emission computed tomography (OPECT). OPECT before the treatment and 6 and 12 months after it evidences that in unilateral RCC, irrespective of the focus location, both kidneys as a single organ respond to tumor growth with compensatory hypertrophy. Compensatory reserve is limited. In tumor size more than 6 cm the affected kidney starts losing the volume of the functional tissue while infiltrative growth is most likely. Assessment of the compensatory potential of the kidneys provides additional information. If the volumes of the kidneys differ by more than 30%, RCC growth is infiltrative. In this case only radical nephrectomy is recommended. If the size of the kidneys is by 60% more than normal one and parenchymas of the affected and contralateral kidney reach their compensatory limit but are equal, indications to organ-saving surgery extend as greater hypertrophy of the remaining kidney is excluded. After organ-saving surgery, a compensatory increase was observed in the contralateral kidney. This is explained by effective distribution of protein material and separate processes of proliferation (healing) and hypertrophy (compensation). Assessment of anatomo-functional condition of renal parenchyma helps better selection of patients for organ-saving surgery.

Emission computed tomography (ECT) was used to examine 48 patients with suspected renal lesions. Sectional images of renal cysts diagnosed in 14 of them were characterized by well-defined outlines surrounded by uniformly declining radiopharmaceutical accumulations. Renal tumors were detected in 25 patients. ECT pattern of the tumor had obscure borders suggesting the tumor invasion into the renal tissue. Accumulation of the radiopharmaceutical round the tumor was less pronounced than in functioning renal tissue. According to ECT findings, 8 subjects were free of urological pathology. It is concluded that ECT is a promising diagnostic tool in urology as it permits sectional visualization of renal neoplasms structure, is highly sensitive, informative and noninvasive. It can identify mass lesions of the kidneys and warrants exhaustive information on functional performance of the renal parenchyma.

The authors present a detailed description of the parameters of gamma-chambers that are necessary to measure in order to assess the quality of the device as a whole. The main concepts have been laid down: resolution, spatial distortion, irregularity of the field of vision of a gamma-chamber, idle time of the system, sensitivity, etc. Methods for the evaluation of the main characteristic of gamma-chambers are considered. A necessity to organize the checking of gamma-chambers in hospitals and other health care facilities and the making up of a common system of assessment are discussed.

A method of assessment of a zone of scintigraphic image based on a textural analysis was proposed. The method was tested by means of an analysis of synthesized images and assessment of 285 scintigrams of various hepatic lesions. The use of the method made it possible to improve the accuracy of differential diagnosis at the expense of defining the structures typical of diffuse and multiple small focal lesions which were undetectable by visualization.

Structural analysis of scintigraphic images was used for assessment of the severity of lung affection in 57 patients with mild, average and severe types of asthma and chronic pneumonia. The results of common methods and microstructural analysis were compared. The use of the latter made it possible to reveal structures which were typical of a various degree of severity in chronic diseases.

A new method of coincidence of scintigrams received from a patient laying in an arbitrary position is proposed. Coincidence of point sources at 2 anatomical reference points is made before examination. Coincidence is realized by rotation and movement of one image relatively to the other one. This method is realized on a specialized data processing system MDS. Programming language is FORTRAN-4. The method is applied to complex examinations of the lungs and liver.

The authors considered the major aspects of the control of the quality of computed emission tomography (SPECT), assessed the influence of the physicotechnical parameters of the instrument, parameters of recording of results and methods of their processing on end-results of investigations. The authors propose a list of controlled parameters, methods of testing and their periodicity; they also describe the techniques and results of some phantom studies using SPECT with the Jaszczak phantom.

The results of the visual evaluation of scintiphotography with MMA-99mTc and studies with 133Xe on 130 patients with different pulmonary pathology (90 with lung cancer) and 40 with nontumorous pulmonary diseases were considered. To improve the reliability of the visual evaluation, the zone and lung coefficients (Kz and K1) were proposed making it possible to raise the specificity of evaluation. The extent of disorders of the blood flow in the lungs was correlated with that of changes defined on the radiographs. In most patients with lung cancer, such disorders exceeded the extent of changes on the radiographs--64.4%. In nontumorous lesions the excess of changes was observed in focal processes (tuberculosis).

The paper is concerned with methods for the determination of the liver volume using polypositional scintigraphy (PS) and computed emission tomography (SPECT). The accuracy of both methods was assessed using a liver phantom. The methods were tested in clinical practice on patients with diffuse liver lesions. A liver volume value compared with values in normometric tables as well as differences between a geometrical volume calculated by PS and a volume calculated by SPECT were of diagnostic importance.