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This paper presents new position-sensitive matrices of photosensitive elements. The photosensitive elements of the proposed matrix can be manufactured, depending on the required spectral range, based on Si, A3B5 solid solutions, etc. Depending on the required technical characteristics, PN photodiodes, PIN photodiodes, or avalanche photodetectors can be used as photosensitive elements. The main advantage of the proposed optical coordinator is a special topology of connection of sensitive elements. The interlaced connection of rows and columns allows to significantly reduce the number of information outputs, expand the dynamic range, and achieve greater manufacturability of the device without significant loss of the signal component. The periodicity of the topology makes it possible to find the position of a light spot, determine its center, and accurately track the movement of the spot along the coordinator without the use of micromechanical centering devices. The "checkerboard" topology of the sensitive elements and method of generating output signals are discussed. Such an arrangement makes it possible to simultaneously determine two coordinates at the same time. Methods for determining the center of a light spot are presented as well. The overlap of the area of the sensitive element by the light spot is proportional to the output current signal. Therefore, it is possible to determine the center of the light spot by solving a two-dimensional geometric problem. The distribution of errors in determining the center was calculated using the method of finding the barycenter in dynamic and statistical modes for different light spot configurations. Directionfinding characteristics were analyzed. A topology of connection that allows to expand the dynamic range of the measurement was submitted.

This article presents the results of treatment of patients with ulcerative gastroduodenal bleeding who were treated in the 2nd clinic (surgery for the improvement of doctors) Military Medical Academy at the I.I. Dzhanelidze Research Institute of Emergency Medicine. A retrospective analysis was conducted of the frequency of rebleeding, surgical activity and mortality in groups with the use of transcatheter arterial embolization with and without it. The criteria for inclusion in the study were: the presence of ulcerative gastroduodenal bleeding, confirmed by laboratory and instrumental methods of examination, severe general somatic condition of patients. The comparison was carried out in the main and control groups. The main group consisted of 20 patients who underwent endovascular hemostasis. The control group included 46 patients without the use of X-ray surgical methods. The average age of patients in the main and control groups was 65.5 3.7 and 60.7 3.9 years. In both groups, most patients were admitted later than 24 hours after the onset of the disease and with severe blood loss. The severity of the somatic state of the intervention was assessed according to the APACHE II multiple organ failure assessment scale, according to which, patients in the main group were somatically more severe than in the control group. In the groups, bleeding from stomach ulcers prevailed (up to 75%). Most often, endovascular hemostasis is performed at a high risk of recurrent bleeding, and adhesive compositions and spirals were used as an embolizing agent. Angiography revealed direct or indirect signs of bleeding (extravasation, hypervascularization, aneurysmal dilatation) in 12 cases, and preventive embolization was performed in 8 cases. In 70% of cases, the source of bleeding was the left gastric artery. In the control group, recurrent bleeding and surgical activity accounted for 26%. In the main group, 20% and 15%, respectively. In the main group, recurrent bleeding occurred in 4 cases, 1 patient underwent repeated endoscopic hemostasis, 3 patients underwent open surgical interventions. All 4 patients had a fatal outcome, against the background of massive blood loss and aggravated somatic pathology. The overall mortality rate in the control group was 44%, in the main group 35%. Transcatheter arterial embolization did not significantly improve the results of treatment of ulcerative gastroduodenal bleeding due to the severity of the general somatic condition of the patients included in the study.