Formation of Surface Plasmon-Polariton Vortices at Reflection from Curvilinear Boundary

We present the results of simulation of interference of surface plasmon-polaritons (SPPs) which are falling and reflecting from the curvilinear boundary of inhomogeneity area in the metal layer. The plasmon vortices with a screw phase dislocation appear in the singular points of the field as a result of the SPP interference after reflection from the boundary of inhomogeneity in the dovetail form. The position of the plasmon vortices on the surface of metal layer can be controlled by means of the external electrostatic field. Negative charges localized at the control probes cause the change of the boundary curvature of the permittivity of inhomogeneity area on the metal layer, which leads to displacement of the vortex localization points. When the vortex is localized under the readout nanowire probe with angular thread, the maximum or minimum of the signal takes place in the probe depending on the helicity of the thread and the topological charge of the vortex. Keywords: surface plasmon-polariton, plasmon vortex, nanowire

ЛУЧЕВАЯ ДИАГНОСТИКА ПОРОКА РАЗВИТИЯ ПЕЧЕНИ

Hepatic malformations are rare. We review the pathogenesis, morphology, classification, clinical presentation, and diagnosis of these malformations. We report a case of an accessory hepatic lobe masquerading as an abdominal tumor and detected with multilayer spiral CT and MRI. We discuss diagnostic signs as well as advantages and limitations of the two methods. The diagnosis was verified by pathology following an unconventional laparoscopic resection of the left hepatic lobe.Пороки развития печени - редкая врожденная патология. В работе приведена краткая информация о механизме возникновения таких аномалий и морфологических формах, о классификациях, клинической картине и возможностях их распознавания. Представлено собственное наблюдение одного из пороков развития печени, а именно наличие добавочной доли печени у пациентки, симулирующей новообразование брюшной полости. Для его идентификации были применены мультиспиральная компьютерная томография и магнитно-резонансная томография. Описана лучевая семиотика выявленной патологии. Отмечены достоинства и ограничения этих методов. Окончательный диагноз был поставлен на основании результатов лапароскопической атипичной резекции левой доли печени и последующего гистологического исследования операционного материала

Failure of Colorectal Anastomosis: Risk Factors, Prevention, Diagnosis, Therapeutic Tactics

Aim. To analyse and generalize available literature data on the problem of colorectal anastomotic leakage after rectal resection. Key findings. Over the last decade, there has been an increasing trend towards sphincter-preserving operations in modern colorectal surgery. The widespread use of suturing devices of various diameters allows the formation of ultra-low anastomoses (at the level of the pelvic floor). One of the menacing complications after rectal resection is anastomotic leakage, which frequency can reach 21%. The mortality from anastomotic leakage can reach 40%. The analysed literature sources discuss a variety of risk factors, both preoperative and intraoperative, affecting the healing of the inter-intestinal anastomosis. In almost all studies, the height of the tumour and the anastomosis from the anus, preoperative radiotherapy and male sex are independent risk factors for the development of colorectal anastomotic leakage. Concerning other factors, there are conflicting opinions. The timely use of preventive measures and early diagnosis of colorectal anastomotic leakage can reduce the number and severity of postoperative complications.Conclusion. Individual consideration of risk factors and their adequate assessment in terms of possible complications are decisive in the choice of the extent of surgical intervention, which will undoubtedly improve the immediate and long-term results of the surgical treatment of colorectal cancer

ЛУЧЕВАЯ ДИАГНОСТИКА ПОРОКА РАЗВИТИЯ ПЕЧЕНИ

Hepatic malformations are rare. We review the pathogenesis, morphology, classification, clinical presentation, and diagnosis of these malformations. We report a case of an accessory hepatic lobe masquerading as an abdominal tumor and detected with multilayer spiral CT and MRI. We discuss diagnostic signs as well as advantages and limitations of the two methods. The diagnosis was verified by pathology following an unconventional laparoscopic resection of the left hepatic lobe.Пороки развития печени - редкая врожденная патология. В работе приведена краткая информация о механизме возникновения таких аномалий и морфологических формах, о классификациях, клинической картине и возможностях их распознавания. Представлено собственное наблюдение одного из пороков развития печени, а именно наличие добавочной доли печени у пациентки, симулирующей новообразование брюшной полости. Для его идентификации были применены мультиспиральная компьютерная томография и магнитно-резонансная томография. Описана лучевая семиотика выявленной патологии. Отмечены достоинства и ограничения этих методов. Окончательный диагноз был поставлен на основании результатов лапароскопической атипичной резекции левой доли печени и последующего гистологического исследования операционного материала