[Nephro-urological monitoring technology based on radionuclide functional tests (tasks of an automated workplace)]. / Tekhnologiia nefrourologicheskogo kontrolia na baze radionuklidnykh funktsional'nykh testov (zadachi avtomatizirovannogo rabochego mesta).

The paper deals with a diagnostic informational and analytical system (DIAS). The system is based on the current concept of a dynamic model of nephro-urological clearance macroregulation under retention factors at the pre-, intra-, and postrenal levels during drug load tests. DIAS includes a package of dynamic renoscintigraphic techniques, as well as original software support. A system for parameters of renal clearance regulation has been developed, which is effective at nephro-urological screening and monitoring at all treatment stages for cancer patients. A two-detector chamber which permits the mounting of a detector at an angle to the patient's body is the optimum diagnostic apparatus for a cancer clinic. The use of functional tests makes it possible to examine the regulatory reserves for each kidney, followed up by the choice of adequate corrective measures to prevent renal failure during treatment. In some cases, DIAS monitoring frequently shows a higher sensitivity to the signs of latent renal failure than does routine clinical and laboratory monitoring. The effective radiation dose taken by a patient during a study by the DIAS technology aimed at reducing radioopaque doses is 100-150 times higher than that at an X-ray study and is an order less than during routine urinary tests.

[Effect of detector sensitivity on the accuracy of results of radionuclide kidney studies]. / Vliianie chuvstvitel'nosti detektora na tochnost' rezul'tatov radionuklidnykh issledovanii pochek.

In the course of both kidney gammachronography with an isolated detector and kidney scintigraphy with a gamma camera the detector volume sensitivity is calculated. Mathematical model of the kidney is described as a set of superimposed linear-circular cylinders. Based on the CT examinations a cylinder radius and a thickness of soft tissues attenuating gamma radiation are derived. The detector volume sensitivity is found to change up to 34% in kidney gammachronography and up to 22% in kidney scintigraphy when using low power radionuclides.

[Prognosis of the postoperative external respiratory function based on radionuclide research data]. / Prognoz posleoperatsionnogo sostoianiia funktsii vneshnego dykhaniia po rezul'tatam radionuklidnykh issledovanii.

A unified indicator was worked out to have an opportunity before pulmonary operation to predict external respiration function in patients in the postoperative period. The value of partial oxygen pressure in the arterialized blood was proposed as such an indicator. The model made it possible to associate external respiration function with sizes of the involved area and the area of future operation. The main allowance of the model was an assumption of the contribution of any segment to the general process of blood oxygenation. Altogether 11 lung cancer patients were examined. Functional examination of the lungs with 133Xe was performed before a supposed operation. The authors showed a close quantitative and qualitative interrelationship between predicted indicators of partial oxygen pressure in the arterialized blood and corresponding values determined by the methods of blood oxygen measurement in the postoperative period.

[Effect of detector sensitivity on regional indices of pulmonary function]. / Vliianie chuvstvitel'nosti detektora na regional'nye pokazateli funktsional'nogo sostoianiia legkikh.

The paper is concerned with a qualitative assessment of the assumption of independence of sensitivity function on the anatomotopographic features of the region in a functional radionuclide study of the lungs. Sensitivity function of standard collimation detectors was calculated for the radionuclides 133Xe and 99mTc. Geometrical sizes of the studied region were determined by respective CT transversal sections. An analysis of the calculation results showed that sensitivity function depended significantly on the anatomotopographic features of the studied region. The error of measurement determined by the variability of sensitivity function, easily changed from 34 to 9%.

[Changes in the regional indices of ventilation and perfusion in lung cancer patients during treatment]. / Izmenenie regionarnykh pokazatelei ventiliatsii i perfuzii u bol'nykh rakom legkogo v khode lecheniia.

A total of 27 patients with central lung cancer and 43 patients with peripheral lung cancer of various sites were examined after surgical intervention on a multichannel unit using 133Xe. The regional distribution of alveolar ventilation and perfusion blood flow were evaluated in the preoperative period as well as at varying times after operation. Statistical analysis of the results has shown that a significant decrease in the ventilation and blood flow is observed in the zone with a focus of lesion in the preoperative period. At the same time even in the preoperative period of compensatory increase in the ventilation and blood flow occurs in the lower zone of the contralateral lung. An increase in the ventilation and blood flow in all the zones of the remaining lung is observed after pulmonectomy; lobectomy does not change pulmonary function and the operated lung does not regenerate its function. No distinctions in the regional values of the ventilation/perfusion ratio were revealed during treatment. Regional perfusion and ventilation are changed in one direction, their ratio and hence the gaseous composition of the blood remain unchanged.