Multidimensional Inverse Boundary Value Problem for a System of Hyperbolic Equations

In the paper we investigate the solvability of the inverse multidimensional boundary value problem for the system of hyperbolic type equations. A method is proposed to reduce the considered problem to some non infinite system of differential equations. The proposed method allows one to prove the existence and uniqueness theorems for the multidimensional inverse boundary value problems in the class of the functions with bounded smoothness

Nephrostomy tube misplacement in the inferior vena cava following percutaneous nephrostomy

Percutaneous renal interventions are characterized by bleeding and infectious complications, as well as trauma to organs located near the kidney, renal or inferior vena cava (IVC). The article presents a clinical observation of a rare complication of percutaneous nephrostomy (PCN), i.e. migration of the distal end of the nephrostomy tube into the IVC. Its timely removal followed by re-nephrostomy made it possible to avoid bleeding and restore drainage of the pyelocalyceal system. Along with this, the article presents a literature review on this condition in the eLibrary, Springer, MedLine, Embase, UpToDate databases from 2000 to 2021. The indications for PCN, the frequency and risk factors of IVC damage during percutaneous renal interventions, as well as treatment tactics were studied. After the initial evaluation of the literature, ten articles were selected for further analysis. The main risk factors associated with IVC perforation after PCN include the surgeon's lack of experience in instrumental imaging, misjudgment of the length of the nephrostomy tube, and its insertion depth, resulting in its inadequate placement. Removal of the nephrostomy tube from the IVC under radiological and ultrasound guidance or open surgery are the main methods to correct for this complication

Retrograde endoscopic-assisted percutaneous treatment of transplanted kidney calyceal fistula

Introduction. Calyceal fistula is a rare complication of a renal transplantation. This complication can lead to postoperative graft failure. The treatment approaches range from a partial nephrectomy to a routine nephrostomy.Objective. To present the successful application of the retrograde endoscopic-assisted percutaneous treatment of transplanted kidney calyceal fistula.Clinical case. A patient after kidney allotransplantation is under our care. Control postoperative ultrasound examination revealed a pararenal fluid mass in the left iliac region. Its percutaneous drainage was performed. Biochemical analysis revealed high levels of creatinine and urea in the drainage discharge. Despite ureteral stent and urethral catheter drainage, about 500 to 600 ml of urine per day was excreted by the drainage. Percutaneous puncture nephrostomy could not be performed due to the absence of dilatation of the renal cavity system. In the lithotomic position, the damaged calyx was identified by performing flexible ureteropyeloscopy. Then we percutaneously targeted the injured calyx and the distal end of the ureteroscope inserted transurethrally, so that the needle tip appeared in the paranephral cavity opposite the injured calyx. Under the control of a flexible ureteroscope the needle was inserted into the kidney pelvis, a nephrostomy tube 12 Ch was placed along the string. The discharge through the drain stopped within a week and it was removed. Follow-up examination nine weeks after surgery revealed that the patient had no complaints and renal ultrasound showed no features, so the nephrostomy tube was removed.Conclusion. The described method is the minimally invasive, affordable, and efficient method for the treatment of transplanted kidney calyceal fistula

Original Russian Text © Ya

Assessing the economic efficiency of medical information technologies calls for a quantitative comparison of costs and results. If the required indicators can be obtained, the efficiency can be estimated using known methods of economic efficiency evaluation for investment projects The next step in coming closer to a solution for the above task is to analyze common approaches to evaluating the efficiency of information systems irrespective of their domain. We should note here the lack of methods reliable in terms of practical application. Practical designs are available only for particular cases where specific conditions related to the type and domain of information systems introduced are assumed. Since a unified approach to the evaluation of information technologies' economic efficiency is not available, special methods must be developed for information systems aimed at solving particular management problems, especially in medicine. Such methods are mostly of a heuristic nature and are based on the study of costs and economic effects after the introduction of information systems in a particular case. If the costs and effects of implementing such systems can be evaluated, it is possible to subsequently apply the above common approach to assessing the economic efficiency of investment projects. The preferred level in solving the problem of assessing the efficiency of medical information systems is hardly attainable; therefore, a positive achievement here would be revealing the positive effects of introducing a particular information system in which each effect is measured by specific quality parameters. The above deductive logic in the development of methods for evaluating the efficiency of medical information technologies is observed in the below analysis of the present state of studies in the topic in question. A General Approach to Evaluating the Economic Efficiency of Investment Projects. Universal methodological recommendations for evaluating the efficiency of investment projects contain general principles and are suitable only for the most typical industrial projects. These methodological recommendations point to the need for using special procedures to assess the economic effects derived from non-standard situations (e.g., in projects for developing science and technology and environmental projects), one sign that the above methodological techniques are aimed at application broader than just the manufacturing of commodities. Such techniques for assessing efficiency should define the preferred area for investing funds among all potential areas in industry, science, public medical, and so on. The same methodological guideline should enable us to compare the efficiencies of any nonstandard projects with those of industrial projects, since the same financial resources are invested in both categories of projects. One problem of evaluating the efficiency of information technologies is describing their effects, which are not revenues from sales of products output and thus differ from the effects of industrial investment projects. The existing methodical guidelines contain references to the probability of such situations. They underline especially that investment is made to acquire a benefit. The tern "benefit" is used to show that the purposes of investment projects are not limited to a net profit in sales, but can take on other forms, e.g., the saving of funds and the prevention of losses. Apart Abstract -The topic of how to assess the economic efficiency of medical information technologies in a model of the system of electronic medical records is considered in this paper. The paper also gives an analysis of foreign approaches that would be interesting to consider for application in Russian conditions to assess the economic benefits of introducing the above information system in inpatient and outpatient care facilities

The three-dimensional reconstruction of the dilated renal pelvicalyceal system by non-enhanced computed tomography

Introduction. The three-dimensional reconstruction of the renal pelvicalyceal system (PCS) is possible when performing enhanced computed tomography (CT). However, the use of a contrast agent has its limitations associated with the presence of allergy and chronic kidney disease.Purpose of the study. To describe the method of semi-autonomous three-dimensional (3D) reconstruction of the PCS based on non-enhanced CT images of patients with upper urinary tract obstruction.Materials and methods. Five patients diagnosed with renal colic were recruited from April-May 2021. All patients underwent CT-urography after informed consent. Medical Imaging Interaction Toolkit program (MITK) expanded with explainable update were used for 3D-reconstruction of PCS via excretory and native phases. To assess the accuracy of the latter, both contrast and non-contrast models were compared regarding their surface area. Also, the PCS of one patient was used to reconstruct virtual endoscopic views based on enhanced and non-enhanced models. Five urologists estimated their similarity and potential use of non-enhanced models for the interventional planning via a Likert scale questionnaire. The resulting models were also analyzed by programmer-engineers to test their suitability for 3D-printing.Results. The average surface area of enhanced and non-enhanced models was 3291 mm2 and 2879 mm2, respectively. Obtained models were suitable for their intraluminal reconstruction and potential 3D-printing. Analyzed properties of non-enhanced models were estimated at 4.5 out of 5.0.Conclusion. The described semi-autonomous reconstruction of the renal PCS based on non-enhanced CT images allows for a short time to reconstruct its 3D-view in patients with the upper urinary tract obstruction

Original Russian Text © Ya

Assessing the economic efficiency of medical information technologies calls for a quantitative comparison of costs and results. If the required indicators can be obtained, the efficiency can be estimated using known methods of economic efficiency evaluation for investment projects The next step in coming closer to a solution for the above task is to analyze common approaches to evaluating the efficiency of information systems irrespective of their domain. We should note here the lack of methods reliable in terms of practical application. Practical designs are available only for particular cases where specific conditions related to the type and domain of information systems introduced are assumed. Since a unified approach to the evaluation of information technologies' economic efficiency is not available, special methods must be developed for information systems aimed at solving particular management problems, especially in medicine. Such methods are mostly of a heuristic nature and are based on the study of costs and economic effects after the introduction of information systems in a particular case. If the costs and effects of implementing such systems can be evaluated, it is possible to subsequently apply the above common approach to assessing the economic efficiency of investment projects. The preferred level in solving the problem of assessing the efficiency of medical information systems is hardly attainable; therefore, a positive achievement here would be revealing the positive effects of introducing a particular information system in which each effect is measured by specific quality parameters. The above deductive logic in the development of methods for evaluating the efficiency of medical information technologies is observed in the below analysis of the present state of studies in the topic in question. A General Approach to Evaluating the Economic Efficiency of Investment Projects. Universal methodological recommendations for evaluating the efficiency of investment projects contain general principles and are suitable only for the most typical industrial projects. These methodological recommendations point to the need for using special procedures to assess the economic effects derived from non-standard situations (e.g., in projects for developing science and technology and environmental projects), one sign that the above methodological techniques are aimed at application broader than just the manufacturing of commodities. Such techniques for assessing efficiency should define the preferred area for investing funds among all potential areas in industry, science, public medical, and so on. The same methodological guideline should enable us to compare the efficiencies of any nonstandard projects with those of industrial projects, since the same financial resources are invested in both categories of projects. One problem of evaluating the efficiency of information technologies is describing their effects, which are not revenues from sales of products output and thus differ from the effects of industrial investment projects. The existing methodical guidelines contain references to the probability of such situations. They underline especially that investment is made to acquire a benefit. The tern "benefit" is used to show that the purposes of investment projects are not limited to a net profit in sales, but can take on other forms, e.g., the saving of funds and the prevention of losses. Apart Abstract -The topic of how to assess the economic efficiency of medical information technologies in a model of the system of electronic medical records is considered in this paper. The paper also gives an analysis of foreign approaches that would be interesting to consider for application in Russian conditions to assess the economic benefits of introducing the above information system in inpatient and outpatient care facilities

The non-biological simulator with the ability to regulate the position of the kidney and bone landmarks: use for training puncture access in percutaneous nephrolithotripsy

Introduction. The non-biological simulators presented in the literature are far from the real human anatomy and are primarily aimed at developing the skill of the pyelocalyceal system (PCS) puncture without the possibility of imitating various intraoperative scenarios.Purpose of the study. To describe the manufacturing and initial testing of the ultrasound-guided PCS puncture simulator with arbitrary placement of bone landmarks and a kidney model, along with the use of a retrograde view during PCS puncture.Materials and methods. This study included training for 5 resident and 2 urologists. Each participant performed the puncture 5 times using an 18-gauge ultrasound-guided needle. A comparison was made between the number of attempts to form access, the duration of the puncture and its correctness (puncture into the small calyx through the papilla), as well as the correctness of determining the target calyx. The trajectory of the needle was retrogradely assessed using a semi-rigid ureteroscope, and the anatomical identification of the selected calyx was assessed using our mobile application.Results. The total number of attempts was 49 and 14 among residents and urologists, respectively. The average duration of the puncture step was 25.2 and 12.0 seconds. In 9/25 cases, residents were able to correctly analyze visual ultrasound information to determine the target calyx. When a contrast agent was injected into the PCS after 63 punctures, no contrast leakage was found.Conclusion. The proposed PCS puncture simulator allows to develop to develop all the necessary skills for cost-effective training of young urologists in the technique of percutaneous access

Virtual reality simulator for developing spatial skills during retrograde intrarenal pyeloscopy

Introduction. Currently, several virtual reality (VR) simulators have been described for the upper urinary tract stone surgery skill development, including retrograde or antegrade nephroscopy. However, their high cost and the lack of a detailed reconstruction of the intraluminal pelvicalyceal system (PCS) appearance limit their implementation into educational process and clinical practice.Objectives. To develop the approach for VR-reconstruction of the intraluminal appearance of the PCS via head mounted device (HMD), as well as estimate its usefulness for novices to improve spatial orientation during retrograde flexible nephroscopy.Materials & methods. Five residents without experience in self-performing retrograde flexible nephroscopy participated in a 7-day training course on the VR simulator developed, during which each novice studied six variants of the PCS. For the procedure simulation, a silicone kidney model was created with the stone placed in the calyx which was selected randomly in each case. Before and after VR-course, each resident assisted the experienced urologist during simulated retrograde nephroscopy to find the stone placed according to random selection. The nephroscopy time and the number of errors in stone-finding during retrograde flexible nephroscopy were analysed.Results. There was a statistically significant decrease in nephroscopy time (on avg by 17.6 minutes, p = 0.043) and errors to find targeted calyx, which was observed once after the training one resident only.Conclusion. The described VR simulator does not require significant time, technical and financial costs, and is available for wide implementation in the training of young specialists

Некоторые административные особенности поддержания материально -технической базы учреждения, оказывающего гражданам России трансплантологическую помощь

In this article, the authors defined the procedure for maintaining the material and technical base of medical centers providing high-tech assistance (especially, transplant care) to Russian citizens. The current regulatory and methodological base determining the procedure for repairs of fixed assets is evaluated, the main issues of capital repair planning in budgetary medical centers providing high-tech medical care are considered. The innovations introduced at the present time into the legislation determining the procedure for capital repairs are defined; the applicable concepts and scope of regulation are disclosed; the procedure for the implementation of major repairs in accordance with the current regulations is considered; the key issues that make it difficult to start capital repairs of the premises in budgetary medical centers providing high-tech medical care to Russian citizens are identified. Administrative and financial discipline while ensuring the working conditions of the material and technical base has been strengthened. Considerable attention should be paid to the medium-term planning of works, preparation of technical documentation, and procurement of funds for preparatory works. Whereas it is necessary to coordinate such decisions with the Ministry of Healthcare of Russia and other governmental institutions in Russia the timing of the implementation of such projects has significantly increased.В данной статье авторами определен порядок поддержания материально-технической базы учреждений, оказывающих высокотехнологичную помощь гражданам России. Проведена оценка действующей нормативной и методологической базы, определяющей порядок капитального ремонта основных средств, рассмотрены основные вопросы планирования капитального ремонта основных средств бюджетных учреждений, оказывающих высокотехнологичную медицинскую помощь. Определены новации, внесенные в настоящее время в законодательство, определяющее порядок капитального ремонта, раскрыты применяемые понятия и сфера регулирования, рассмотрен соответствующий действующим нормативам порядок осуществления капитального ремонта, определены ключевые позиции, вызывающие затруднения при подготовке капитального ремонта недвижимости бюджетных медицинских центров, оказывающих гражданам России высокотехнологичную медицинскую помощь. Административно-финансовая дисциплина при обеспечении рабочего состояния материально-технической базы усилилась. Значительное внимание необходимо уделить среднесрочному планированию работ, подготовке технической документации, изысканию средств на подготовительные работы. В связи с необходимостью согласования таких решений с Минздравом России и с Главгосэкспертизой России сроки реализации такого рода проектов значительно возросли