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Introduction. It is established that the most effective tool for monitoring and controlling the dynamics of current trajectories (CT) of unmanned vehicles (UMV) when moving along opencast mine routes in open pit mining is the wavelet transforms technique. Methodology. A detailed analysis of the procedures related to the technology of converting 1D-current trajectory signals (CT-signals) into a multidimensional medium of time-frequency distributions (TFD) is carried out. The Wigner distribution is selected as a working distribution for processing CT-signals. This distribution is considered from the point of view of its ability to represent one-dimensional CT-signals of UMV in an information-intensive and functionally transparent format of specific TFDs. Research results and analysis. On the example of curved routes, the nature of the so-called forward and reverse transients of CT-signals of UMV, formed in the subsystems of external and autonomous control (ECSS and ACSS) of unmanned vehicles, is considered. Mathematical tools are described for wavelet transformations: Gabor wavelet functions, the wavelet matching pursuit algorithm (MP-algorithm), and Cohen’s class time-frequency wavelet distributions. Conclusion. The procedures of processing the trajectory signals with using the means mentioned above make it possible to implement effectively the functions of controlling the UMV movement along current trajectories formed by the system on opencast mine routes.

Introduction. The article presents the results of studies related to the description of the synthesis and further analysis of the dynamic behavior of unmanned vehicles (UMV) operating in coal-mining pits and other mining quarries. The urgency of the discussed study is dictated by the need to create safe and effective conditions for stripping / mining and transportation operations. This is ensured, among other things, by the operation of unmanned heavy-duty dump cars. Research aim is to develop the concept for the formation of route parameters and models of the movement dynamics of vehicles along technological routes. Methodology. The paper describes the technology for generating and processing the signals in control subsystems as parts of both the computer-aided dispatching system and the on-board autonomous ISSN 0536-1028 «Известия вузов. Горный журнал», № 8, 2020 119 control subsystem of the UMV. The methods used in the research include the study of the forms and characteristics of current trajectories (CT) in relation to a nominal axial trajectory (NAT). In this case, a current trajectory of the UMV is considered within the framework of the so-called S-frames, which are generated in the form of geolocations on a working route of the UMV from the mining face to the place of unloading and vice versa. As a variable characterizing the behavior of the UMV on a current trajectory, a 1D-signal with a time-dependent frequency is adopted, the nature of the change of which is determined by the dynamic shape of a CT with regard to the NAT. Results. Such chirp-signals, together with the wavelet transform apparatus introduced into consideration, allow in a semantically transparent and information-rich video graphic form to represent and subject to further processing the signals characterizing a certain UMV current behavior on the route. The obtained parameters of such secondary wavelet representations of the UMV current dynamics (wavelet maps) are further planned to be used in the subsystem for dynamic modal controlling the UMV movement in the opencast mine. Conclusions. The results of the research allow us to form current routes of UMVs movement according to the models based on the analytical tools accompanying the dynamics of the UMV, proposed in the work.

Objectives: To describe the clinical characteristics of hip involvement in juvenile idiopathic arthritis (JIA) from arthritis to hip osteoarthritis (HOA) and total hip arthroplasty (THA).Study Design: Seven hundred fifty-three patients aged 2–17 years with JIA were included in the study. The comparison analysis was performed between the following subgroups: (i) JIA without hip involvement (n = 600; 79.7%) vs. JIA with hip involvement without HOA (n = 105; 13.9%), (ii) JIA with hip involvement with HOA, but without THA (n = 32; 4.3%) and JIA with hip involvement with HOA and with THA (n = 16; 2.1%). Clinical, laboratory characteristics and treatment regimens compared.Results: Hip involvement was present in 20.3% of patients. HOA was present in 6.4% (12*1,000 patient-years) of the entire JIA group and 31.4% of patients with hip involvement. Sixteen patients (2.1%; 4.0*1,000 patient-years) required THA. The following factors were associated with HOA: sJIA (OR = 3.6, p = 0.008; HR = 3.0, p = 0.002), delayed remission (OR = 4.2, p = 0.004; HR = 1.4, p = 0.538), delay in biologic therapy initiation (OR = 7.5, p = 0.00001; HR = 6.7, p = 0.002), alkaline phosphatase p = 0.0003; HR = 5.2, p = 0.000004), treatment with corticosteroids (CS) (OR = 2.6, p = 0.008; HR = 1.2, p = 0.670), cumulative corticosteroids >2,700 mg (OR = 4.3, p = 0.032; HR = 1.4, p = 0.527). The following factors were associated with THA: delay in biologic treatment initiation (OR = 1.04, p = 0.0001; HR = 9.1, p = 0.034), delayed hip involvement (OR = 5.2, p = 0.002; HR = 3.0, p = 0.044), and methylprednisolone pulse therapy (OR = 10.8, p = 0.0000001; HR = 5.6, p = 0.002).Conclusion: Both sJIA and systemic CS, impaired calcium-phosphorus metabolism, and delayed hip arthritis are associated with HOA development in JIA. HOA is considered to be a severe adverse event of CS treatment, especially delayed hip involvement.

Objectives: Diagnostic between multisystem inflammatory syndrome associated with COVID-19 in children (MIS-C) and Kawasaki disease (KD) can make difficulties due to many similarities. Our study aimed to create a Kawasaki/MIS-C differentiation score (KMDscore) allowing discrimination of MIS-C and KD.Study design: The retrospective multicenter cohort study included clinical, laboratory, and instrumental information about MIS-C (n = 72) and KD (n = 147). The variables allowed to discriminate both conditions used to construct and validate the diagnostic score called the KMDscore.Results: Patients with MIS-C were older, had earlier admission to the hospital, had a shorter time before fever resolution, two times frequently had signs of GI and CNS involvement observed, and had more impressive thrombocytopenia, higher level of CRP, ferritin, ALT, AST, LDH, creatinine, triglycerides, troponin, and D-dimer compared to KD patients. Respiratory signs in MIS-C were presented with pleuritis, acute respiratory distress syndrome, oxygen dependency, lung infiltration, and ground-glass opacities in CT. The heart involvement with fast progression of myocarditis provided the severity of MIS-C and ICU admission due to 12 times higher arterial hypotension or shock and required cardiotonic. No differences in the frequency of CA lesions were seen in the majority of cases. Five criteria, CRP >11 mg/dl (18 points), D-dimer >607 ng/ml (27 points), age >5 years (30 points), thrombocytopenia (25 points), and GI involvement (28 points), were included in the KMDscore. The summa >55 points allowed to discriminate MIS-C from KD with a sensitivity of 87.5% and specificity of 89.1%.Conclusion: The KMDscore can be used to differentiate the diagnostic of MIS-C from KD.

There are International and Russian guidelines for the diagnosis and treatment of medullary thyroid carcinoma. There is a recommendation to determine the basal level of calcitonin for all patients with nodular thyroid disease at the all of these documents. However, this test is not performed for this category of patients routinely even in large clinics for a number of reasons, the main one, which seems to be an economic issue. Six months ago a patient addressed to our clinic who underwent surgical treatment for a papillary carcinoma (follicular variant) of the thyroid gland in the volume of thyroidectomy with pre-tracheal lymphodissection and subsequent course of radioiodine therapy at the place of residence. A relapse of the disease was suspected on the control examination at the place of residence and the patient was sent for consultation to the polyclinic of the N.N. Blokhin National Medical Research Center of Oncology. In our clinic, diagnostic studies were carried out, including a revision of the finished cytological and histological preparations and a conclusion was obtained – medullary carcinoma of the thyroid. Determination of basal level of calcitonin in serum showed a value of 1292 pg/ml. The level of basal calcitonin significantly decreased after repeated surgical treatment. This case shows that in order to avoid such mistake, which is described in our clinical case, it seems necessary to follow the national recommendations, international standards to determine the level of basal calcitonin for all patients with thyroid nodal pathology who consulted and treated in medical institutions.

This work includes a project to develop a method that provides an advantage to the developer in three areas. The first is to improve the usability of developing iOS applications. The second is to reduce labor costs when developing and finalizing iOS applications. The third is to improve the user experience of using applications. A reactive approach is required to prioritize requests and to avoid erroneous duplicate requests. The developed method implements the reactive programming approach. The authors of the organization make use of the framework as the main data flow tool for organizing network requests in an iOS application. This ensures that you can opt out of all third-party technical solutions. The proposed method can be proposed in the development and refinement of applications for iOS, iPadOS, TVOS and macOS.

The purpose of the study is to determine the ways which intensify the investment activity of enterprises in the Russian Far East. They performed the comparative analysis of the rating methods used in the Russian Federation to assess the investment attractiveness of the regions. It was revealed that a common characteristic of the analyzed methods is to consider the infrastructural factor and their institutional environment, and, in particular, the presence and quality of the business support infrastructure. These factors directly affect the investment attractiveness of a single enterprise and project, as they form the investor's attitude. To increase the investment attractiveness of the Russian Far East regions, it is necessary to use the experience of the Asia-Pacific countries. The work formulated recommendations on the application of Chinese experience in relation to Russian territories with preferential economic regimes. To solve the problem of efficiency, increase and intensity the investment activities of enterprises, the concept of management. accounting tool application is proposed.

Purpose: The purpose of the paper is to determine the perspective directions of implementing information technologies in the Russian criminal justice and to find the most effective means of using “smart” digital technologies in the production investigatory and other procedural actions (electronic document turnover, SMS notification, video conference, etc.).

Purpose: The paper analyzes the effects of smart solutions implemented in social practices on boosting social and human capital and change in the quality of life. Its major objective is to specify the conditions under which smart technologies contribute to increasing depersonalized and institutional trust as components of social capital or public good.

With the progress of COVID-19 studies, it became evident that SARS-CoV-2 infection is often associated with thrombotic complications. The goal of our present study was to evaluate which component of clot formation process including endothelial function, platelets aggregation and plasma coagulation, as well as endogenous fibrinolysis in patients with COVID-19 correlates with the severity of the disease. We prospectively included 58 patients with COVID-19 and 47 healthy volunteers as a control group that we recruited before the pandemic started. It turns out that plasma coagulation with subsequent platelet aggregation, but not endothelial function, correlates with the severity of the COVID-19. IL-6 blockade may play a beneficial role in COVID-19 induced coagulopathy.

ObjectivesThe association between obesity and atrial fibrillation (AF) is well-established. We aimed to evaluate the impact of index body mass index (BMI) on AF recurrence at 12 months following catheter ablation using propensity-weighted analysis. In addition, periprocedural complications and fluoroscopy details were examined to assess overall safety in relationship to increasing BMI ranges.MethodsBaseline, periprocedural and follow-up data were collected on consecutive patients scheduled for AF ablation. There were no specific exclusion criteria. Patients were categorised according to baseline BMI in order to assess the outcomes for each category.ResultsAmong 3333 patients, 728 (21.8%) were classified as normal (BMI 2), 1537 (46.1%) as overweight (BMI 25.5–29.0 kg/m2) and 1068 (32.0%) as obese (BMI ≥30.0 kg/m2). Procedural duration and radiation dose were higher for overweight and obese patients compared with those with a normal BMI (p=0.002 and p2led to a 1.2-fold increased likelihood of experiencing recurrent AF at 12-months follow-up as compared with overweight patients (HR 1.223; 95% CI 1.047 to 1.429; p=0.011), while no significant correlation was found between overweight and normal BMI groups (HR 0.954; 95% CI 0.798 to 1.140; p=0.605) and obese versus normal BMI (HR 1.16; 95% CI 0.965 to 1.412; p=0.112).ConclusionsPatients with a baseline BMI ≥30 kg/m2have a higher recurrence rate of AF following catheter ablation and therefore lifestyle modification to target obesity preprocedure should be considered in these patients.

Introduction: The majority of patients with severe COVID-19 suffer from delirium as the main sign of encephalopathy associated with this viral infection. The aim of this study was to identify early markers of the development of this condition. Materials: The prospective cohort-based study included patients with community-acquired pneumonia and confirmed pulmonary tissue infiltration based on CT data, with a lesion consisting of at least 25% of one lung. The main group included patients who have developed acute encephalopathy (10 patients, 3 (30%) women, average age, 47.9 ± 7.3 years). The control group included patients who at discharge did not have acute encephalopathy (20 patients, 11 (55%) women, average age, 51.0 ± 10.5 years). The study collected clinical examination data, comprehensive laboratory data, neurophysiological data, pulse oximetry and CT data to identify the predictors of acute encephalopathy (study ClinicalTrials.gov identifier NCT04405544). Results: Data analysis showed a significant relationship between encephalopathy with the degree of lung tissue damage, arterial hypertension, and type 2 diabetes mellitus, as well as with D-dimer, LDH, and lymphopenia. Conclusions: The development of encephalopathy is secondary to the severity of the patient’s condition since a more severe course of the coronavirus infection leads to hypoxic brain damage.

We solve the optimization problem for space trajectories of spacecraft flights with an auxiliary fuel tank from a low round orbit of a man-made Earth satellite to a geotransitional orbit. Control over the spacecraft motion is performed with a jet engine of bounded thrust. To discard the auxiliary tank, one has to turn off the engine, which takes some known time. The mass of the discarded tank is assumed to be proportional to the mass of fuel spent, and the mass of the engine and additional constructions is proportional to the thrust-to-weight ratio. We minimize the value of injection impulse needed to transfer to the geostationary orbit for a given useful mass. In the second part of the paper the problem at hand is formalized as an optimal control problem for a collection of dynamical systems and is solved based on the corresponding maximum principle. In this work we solve boundary problems of the maximum principle numerically with the shooting method. As a result of solving the problem, we construct one- and two-revolution Pontryagin extremals. We perform a series of parametric computations that are used to determine optimal parameters of the spacecraft construction: the best thrust-to-weight ratio and the best distribution of fuel among the tanks.

The chapter contains a brief description of chapters that contribute to the development and applications of computational methods and parallel algorithms in different areas of gas dynamics, aerodynamics, hydrodynamics, turbulence, solids dynamic, dynamic systems, optimal control. The first part presents the recent advances in computational fluid dynamics and aerodynamics. The second part introduces a numerical simulation of multiphase flows, combustion, and detonation. The third part is devoted to computational solid mechanics, and the fourth part provides a numerical study of dynamic systems.

This article reflects the main stages of development of high-dose chemotherapy with autologous stem cell as an effective method of treatment of various hematological, oncological and hereditary diseases. It describes the development of the research beginning with the discovery of the stem cells by A.A Maksimov to the contemporary ways to elaborate them into blood; it reflects the basic mechanisms of action of different groups of drugs on complex biochemical cascades close interaction with hematopoietic cells of the bone marrow microenvironment, which, in turn, determines their further destiny and lead to a loss of hematopoietic stem cells in peripheral blood. However, in spite of the current approaches to improve ways of harvesting stem cell, there is a certain percentage of patients in whom it is impossible to collect adequate for quick recovery of hematopoiesis after high-dose chemotherapy number of cells. This percentage will vary according to various literature sources, 5 to 40 %. Therefore, the development and application of new drugs, growth factors and cytokines, which would overcome the problem of poor mobilization is an important issue in modern medicine. The article presents data on the use of a new mobilizing agent plerixafor, the use of which in practice improves the successful mobilization of 40 %. The study of its combined action of various growth factors, including pegylated filgrastim, is a promising direction, because can be a good option for patients with poor mobilization activity for which the previous regimen mobilization proved ineffective. The research of plerixafor interacting with various growth factors including pegylated filgrastim is considered to be the most promising direction. This method is believed to help patients with low mobilizing activity where all other means have failed to improve it.

Objectives: Despite advances in screening and prevention, rates of premature coronary artery disease (CAD) have been stagnant. The goals of this study were to investigate the barriers to early risk detection and preventive treatment in patients with premature CAD. In particular, we: 1) assessed the performance of the latest versions of major international guidelines in detection of risk of premature CAD and eligibility for preventive treatment; and, 2) investigated real-life utilization of primary prevention with lipid-lowering therapies in these patients. Methods: We included patients in the Study to Avoid cardioVascular Events in British Columbia (SAVE BC), an observational study of patients with premature (males ​≤ ​50 years, females ​≤ ​55 years) angiographically confirmed CAD. Eligibility for primary prevention and treatment received were assessed retrospectively based on information recorded prior to or at the index presentation with CAD. Results: Of 417 patients (28.1% females) who met the criteria, 94.3% had at least one major cardiovascular risk factor. In the retrospective risk assessment, 41.7%, 61.4%, and 34.3% (p ​

A corrigendum on «Medullary thyroid cancer. Returning to the need to determine the preoperative basal calcitonin level in patients with thyroid nodular pathology» by Elena E. Stanyakina, Ilia S. Romanov, Tatiana T. Kondratieva, Alexander S. Krylov, Alexey D. Ryzhkov, Sergey V. Shiryaev (2018). Endocrine Surgery. 12(4). doi: 10.14341/serg10044 There is an error on the page 189: "Blood test for hormones: thyroid stimulating hormone (TSH) — 52.6 mIU/l (reference values 0.25–4.0), adrenocorticotropic hormone (ACTH)

Percutaneous renal ablation is often performed under conscious sedation and without contrast-enhanced imaging. We evaluated intermediate-term outcomes of patients undergoing percutaneous contrast-enhanced computed tomography (CT)-guided radiofrequency ablation (RFA) under general anesthesia (GA) at two high-volume centers.Prospectively maintained Institutional Regulatory Board-approved databases were searched to identify patients treated with percutaneous RFA using contrast-enhanced CT under GA. A total of 163 masses in 151 patients were treated. Enhancement on imaging or a positive biopsy at 4 to 6 weeks was considered incomplete ablation. Positive findings beyond this interval were defined as local recurrence.The median follow-up was 18 months (range, 1.5-70). Median tumor size was 2.3 cm (range, 1-5.4). Of the 130 (80%) masses with definitive pathology, 70% were renal cell cancer. Five masses had evidence of viable tumor at 4 to 6 weeks posttreatment for a complete initial ablation rate of 97%. Three of these five lesions were endophytic. Five masses (3.3%) showed evidence of local recurrence, and metastases developed in two patients (1.3%). Overall 1- and 3-year recurrence-free survival was 97% and 92%, respectively. Masses that were in the central region and were endophytic had the highest risk for recurrence (hazard ratio, 6.3; p = 0.016).Intermediate-term outcomes of percutaneous RFA are excellent. GA-assisted, contrast-enhanced CT-guided percutaneous RFA demonstrates a high initial ablation success rate. However, endophytic and interpolar lesions are at higher risk for recurrence.

Introduction and Objective Recent advances in magnetic resonance (MR) technology have allowed for high-resolution ex vivo spectroscopy on small, intact tissue samples. We examined the capability of 1 H magnetic resonance magic angle spinning (MR-MAS) to correctly characterize post–radiofrequency ablation (RFA) renal biopsies from human samples, compared with standard histology and cross-sectional imaging. Methods A minimum of two, 18G, percutaneous renal biopsies were obtained from ten biopsy-confirmed renal tumors at a mean 26.6 mo (range, 15–48) post-RFA. All patients were considered free of disease by computed tomography criteria. A portion of each sample was immediately frozen at −80°C for spectroscopy and the remainder used for pathological analysis. 1 H MR-MAS was performed blinded with a 14.1-tesla field strength. Prior renal biopsies from nonablated tissue were used as positive controls for the spectral analysis. Concordance between, computed tomography, histology, and MR-MAS was analyzed. All spectroscopy was processed with VNMR software. Results Histological analysis of all ten post-RFA biopsies demonstrated no cancer or viable tissue. All MR-MAS spectral peaks for each biopsy were consistent with necrosis and, more importantly, indicated an absence of small molecule metabolites characteristic of both normal and malignant renal tissue. Both MR-MAS and histology confirmed, in each case, the conventional computed tomography determination of complete ablation. Conclusions MR spectroscopy can correctly diagnose the molecular absence of disease in post-RFA tissue biopsies. This proof of principle study warrants in vivo evaluation to confirm the clinical correlates of this modality.

Objectives Optical reflectance spectrophotometry (ORS) is part of a group of novel techniques that have demonstrated promise for the assessment and differentiation of various solid tumors. In this study, we evaluated the ability of ORS to differentiate malignant from benign kidney tumors at surgery. Methods From January to April 2007, we completed optical spectroscopy measurements (OSM) at several standardized tumoral and normal parenchymal locations immediately after specimen removal during radical or partial nephrectomy. The depth of tissue penetration with our specific probe was 1 mm. We compared the slopes of the optical reflectance curves between 630- and 900-nm wavelengths and assessed the correlation between benign and malignant tumors. Results There were 8 partial and 13 radical nephrectomies for 6 benign (oncocytomas) and 15 malignant (14 clear cell and 1 papillary) tumors. Overall, benign and malignant OSM slopes were significantly different ( P = .005). In the near-infrared region, there was excellent correlation among benign ( r = .99) and malignant OSM ( r = .97). On the contrary, there was a poor correlation coefficient when we compared benign and malignant tumors ( r = .49). Conclusions Optical reflectance spectrophotometry may be a novel real-time method to distinguish malignant from benign tumors in vivo. However, we performed these pilot study measurements immediately after specimen removal, and therefore expansion to in situ assessments is necessary.

Radio frequency ablation is an emerging nephron sparing treatment option in select patients with small renal tumors. Some have questioned the completeness of cell death and the reliability of axial imaging for radio frequency ablation followup. We present results in patients with no evidence of radiographic active disease who underwent biopsy more than 1 year following ablation.Patients who had no clinical evidence of disease, defined as absent lesion growth and contrast enhancement on computerized tomography, 1 year or more following radio frequency ablation underwent percutaneous renal biopsy to evaluate cell viability in the ablative zone. A total of 19 patients (20 lesions) were included in the study. Histological comparison of pre-ablation and post-ablation specimens was performed using hematoxylin and eosin staining.Pre-ablation biopsies confirmed that 17 of 20 tumors were renal cell carcinoma, while the remaining 3 were oncocytoma. Following ablation at a mean followup of 26.9 months (range 13.1 to 58.0) all 20 lesions were stable in size without evidence of contrast enhancement on computerized tomography. At repeat biopsy all histology specimens showed unequivocal tumor eradication with no evidence of cellular viability. Histological changes beyond 1 year demonstrated coagulative necrosis, hyalinization, inflammatory cell infiltration and residual ghost cells.Pathological examination of radiographically negative lesions biopsied more than 1 year following radio frequency ablation confirmed no evidence of disease in all specimens. Therefore, axial imaging can reliably monitor treatment efficacy in the long term. Chronic changes after radio frequency ablation demonstrate coagulative necrosis and nonviable cells. This suggests an evolution of pathological changes that renders early post-ablative biopsy unreliable.

HABIB 4X is a laparoscopic focal radiofrequency-coagulation (FRFC) device utilized in liver and kidney resections to facilitate dissection while minimizing blood loss. We evaluated the ergonomics and safety of a laparoscopic FRFC device for a non-ischemic laparoscopic partial nephrectomy (LPN) in a survival porcine model.Five female pigs (10 renal units) underwent 14 laparoscopic transperitoneal partial nephrectomies using the laparoscopic FRFC device without hilar clamping. In phase 1, either one or multiple segments of the lower, upper, or middle pole were resected following FRFC of the resection plane. Large entries into the collecting system were sutured, while very small rents were left open. Following 2-week survival, a laparoscopic FRFC-assisted heminephrectomy without hilar clamping was performed on the opposite renal unit (phase 2). Both kidneys were then harvested for histologic examination. Retrograde pyelography (RGP) was used to assess the collecting system integrity of the kidneys treated in phase 1.All 14 LPNs were performed successfully without hilar clamping or open conversion. On average, the resected segments comprised 12.3% of the kidney in phase 1 and 34.8 % in phase 2, with a mean estimated blood loss of 45 mL and 76.5 mL, respectively. At harvest, no hematomas or perinephric collections were observed. RGP revealed urinary extravasation in two renal units that were not repaired. Histologic examination of the resection margin revealed hemorrhage and inflammation with some hyalinization of the proximal and distal tubules, none extending deeper than 3 mm.The FRFC-assisted non-ischemic porcine LPN is feasible and safe and can be accomplished with minimal bleeding, even with large resections. The laparoscopic FRFC device holds promise in decreasing the inherent difficulty of LPN by obviating the need for laparoscopic suturing to control small parenchymal vessels, as well as in reducing the deleterious effects of warm renal ischemia. Clinical evaluation of this device is warranted.

We assessed the feasibility of single keyhole laparoscopic surgery using a novel transabdominal magnetic anchoring and guidance system platform in the porcine model.A collaborative research group was formed to build a prototype system of magnetically anchored instruments for trocar-free laparoscopy. The design mandate was that the developed technology should be able to deploy into the insufflated abdomen through an existing 12 mm diameter trocar and then be moved into position in the peritoneum by manipulating external magnets. The magnetic anchoring and guidance system concept was advanced to a working prototype with a system of external magnetic anchors, an internal camera system and a hook cautery supported by an intra-abdominal robotic arm. This prototype system was then evaluated in vivo in a porcine laparoscopic nephrectomy model.Two nonsurvival porcine laparoscopic nephrectomies were successfully completed without complications via a single 15 mm transumbilical trocar using the prototype magnetic anchoring and guidance system camera and the magnetically anchored robotic arm cauterizer. A conventional laparoscopic grasper was used for retraction through the 15 mm trocar after magnetic anchoring and guidance system deployment. The renal artery and vein were transected with a conventional Endo-GIA stapler introduced through the 15 mm trocar. Procedure time was not recorded and blood loss was minimal.Single trocar laparoscopic nephrectomy using magnetically anchored instrumentation is technically feasible, demonstrating that intracorporeal instrument manipulation may overcome the limitations of current laparoscopic and robotic surgery by allowing unhindered intra-abdominal movement. This single access technique may be used with natural orifice surgery approaches and it has the potential to realize incision-free intra-abdominal surgery.

To compare stone retrieval and release from seven basket designs in vitro.We tested two tipped and one tipless NCompass models, three other tipless Nitinol designs (NCircle, Sur-Catch, and Dimension), and the Segura Hemisphere for their ability to retrieve and release single beads 8, 6, 5.6, and 5 mm diameter and multiple beads 3.6 mm diameter in both a ureteral and a caliceal model in three separate attempts.In the ureteral model, all baskets were successful in retrieving all sizes of single beads. With multiple 3.6-mm beads, only the NCompass and Dimension designs were able to retrieve at least two of three beads in all attempts. With the exception of the Segura Hemisphere, all designs were successful in releasing all bead sizes. In the caliceal model, only the NCircle, Dimension, and tipless NCompass models were able to retrieve all bead sizes in 100% of the trials. The tipped NCompass and Hemisphere designs were unable to retrieve any beads in this model. The Sur-Catch basket was successful in the retrieval of large beads only. The Dimension articulating design was the only basket able to release all bead sizes in all attempts. The tipless NCompass basket did not release any of the beads once engaged.Nitinol basket designs show excellent retrieval and release capabilities in the in-vitro ureteral model. The articulating Nitinol basket has the best stone-releasing capability of all baskets tested.

Percutaneous renal access is an integral step in percutaneous renal drainage and percutaneous nephrolithotomy. Urologists are increasingly obtaining access themselves, as this eliminates reliance on a second "surgeon" and increases flexibility with respect to procedure timing and the location of the access tract. Surprisingly few models have been developed to train urologists in percutaneous renal access. Harvested porcine kidney/ureter units mounted so they can be viewed radiographically and accessed by needle puncture through material simulating the human flank have been incorporated into two models. The PERC Mentor (Simbionix; Lod, Israel) is a virtual-reality simulator developed specifically for training in percutaneous renal puncture. Hands-on intraoperative training continues to be the primary method for learning percutaneous renal access. However, bench model and simulator-based education offer a useful adjunct.

We estimated the incidence of a crossing vessel at the normal ureteropelvic junction (UPJ) in patients undergoing ureteroscopy and endoluminal ultrasonography for indications other than UPJ obstruction.Endoluminal ultrasonography was performed in 141 patients undergoing upper tract endoscopy for various indications excluding UPJ obstruction. A detailed description of the anatomy of the UPJ as well as the location and size of crossing vessels was included in the operative note. Charts were reviewed to determine the precise anatomy of the UPJ.The overall incidence of crossing vessels at the unobstructed UPJ was 19.2%. Endoluminal ultrasonography demonstrated a crossing vessel in 13.2% of patients with ureteral narrowing or stricture, 31.3% of those with tumors or filling defects, 10.5% of those with submucosal calculi and 16.7% of patients with ureteral diverticula. In cases where the position of a crossing vessel was ascertained, 41% were anterior to the ureter, 28% anterolateral, 24% anteromedial and 7% posterior. There was a statistically significant difference in the frequency of vessels at the UPJ in patients with and without obstruction examined with endoluminal ultrasound (p0.0001).A crossing vessel at the UPJ is seen with endoluminal ultrasound in 19.2% of patients with a normal UPJ. This incidence is lower than that seen in patients with obstructed UPJ. Many of these vessels are related to the lateral surface of the UPJ and there was no area that was always free of vessels.

Laparoscopic dismembered pyeloplasty is an acceptable option for ureteropelvic junction (UPS) obstruction in the pediatric population. We compared our results with dismembered and nondismembered laparoscopic pyeloplasty.A series of 26 children between the ages of 8 months and 15 years (mean age 5 years) underwent transperitoneal laparoscopic pyeloplasty for an obstruction not caused by a crossing vessel. Nineteen had an Anderson-Hynes dismembered pyeloplasty (AH), while the remaining seven had a nondismembered pyeloplasty in a Heineke-Mikulicz fashion (HM). The outcome measures were operative time, length of hospital stay, and resolution of obstruction by ultrasonography and diuretic radionuclide imaging.The mean operative time was 3.1 hours and 2.5 hours for AH and HM, respectively. No difference in hospital stay was noted, with a mean of 3 days. The stent was removed 6 weeks later. Four of the seven patients having nondismembered procedures presented with acute flank pain within 3 days of stent removal. The AH pyeloplasty produced a 94% rate of resolution of UPJ obstruction, while the HM patients did poorly, with a success rate of only 43% (P = 0.002; Fisher's exact test).We believe that for UPJ obstructions in children not involving a crossing vessel, laparoscopic dismembered (AH) pyeloplasty may be considered a safe alternative.

We present our experience with transperitoneal laparoscopic pyelolithotomy in pediatric patients in whom percutaneous renal access failed and the stone burden warranted open intervention.A transperitoneal laparoscopic approach was used for pyelolithotomy in 8 patients 3 months to 10 years old (mean age 4 years). Percutaneous access failed secondary to a nondilated system and/or an occluding lower pole calculus. Inclusion criteria were failed percutaneous access secondary to a nondilated system and/or stone occlusion of the lower pole system and failed shock wave lithotripsy or a stone burden of greater than 2.5 cm2. A posterior pelviotomy was made. Stones in the renal pelvis were removed with rigid graspers under direct laparoscopic vision. A flexible cystoscope was introduced through a port if caliceal stones were present. The renal pelvis was reconstructed. A watertight anastomosis was verified.Average operative time was 1.6 hours (range 0.8 to 2.3). Mean hospital stay was 2.15 days (range 2 to 3). A range of 1 to 3 stones (median of 1) were removed and the mean stone burden was 2.9 cm2. No intraoperative complications were noted. Stone analysis revealed 3 patients with calcium oxalate stones, 1 with a calcium phosphate stone and 4 with cysteine stones. There was 1 patient with stone recurrence at a mean followup of 12 months (range 3 to 20). Thus, the overall long-term stone-free rate was 87.5%.Transperitoneal laparoscopic pyelolithotomy is feasible when percutaneous access fails and open pyelolithotomy is considered due to a large stone burden.

There have been improvements in the outcome of patients with clinically localized prostate cancer treated by radical prostatectomy. However, some patients treated with radical prostatectomy will have clinical or biochemical progression. These men are at increased risk of dying of their disease. Identification of patients with adverse features at the time of radical prostatectomy may permit the use of additional multimodality therapies to improve outcomes. Whether this additional multimodality therapy should be administered in the neoadjuvant or adjuvant setting remains controversial. Further, whether a patient at increased risk for progression after radical prostatectomy requires additional therapy before the development of documented progression remains controversial. This article reviews the potential multimodality approaches to prevent or delay recurrence of prostate cancer in patients undergoing surgical treatment for prostate cancer.

OBJECTIVE To assess the functional and histological effects of a bovine thrombin topical haemostatic agent used clinically to aid in surgical haemostasis (FloSealTM, Baxter International Inc., Deerfield, IL, USA) on the cavernous nerves in a canine model of survival, as there are concerns that the fibrotic/inflammatory response to this product could affect neural function. MATERIALS AND METHODS In phase I, nine adult male dogs had the bilateral neurovascular bundles (NVBs) dissected. A small intravenous catheter placed directly into the erectile bodies of the penis was used to record the intracorporal pressure (ICP). Erection was induced by electrical stimulation of the NVB on each side. After intraoperative randomization to treatment or control, 5 mL of FloSeal was unilaterally applied along the NVB on the treatment side. In phase II, after 2 weeks of survival, both control and treatment NVB were again dissected and re-stimulated to produce an erectile response. The mean arterial pressure and ICP were recorded. The prostate and the NVBs were then removed for histological analysis. RESULTS All dogs achieved erections after electrical stimulation on both the control and treatment side. There was no statistically significant difference in absolute ICP, pressure increase from baseline or systemic pressure after stimulating the NVB on the treatment side between phases I and II. Histological analysis showed a giant-cell reaction around the FloSeal granules and mild focal perineural oedema, but the cavernous nerves were otherwise normal in appearance. CONCLUSION In this short-term functional study, FloSeal did not adversely affect cavernous nerve function, measured as the erectile response to electrical stimulation. We found no evidence contraindicating its use during radical prostatectomy.

A transabdominal magnetic anchoring and guidance system (MAGS) deploys multiple instruments through a single 15-mm diameter, transabdominal trocar. These instruments are positioned in the peritoneal cavity and controlled by externally placed magnets to reduce the need for multiple transabdominal trocars. To assess the feasibility of MAGS technology in a single keyhole, complex laparoscopic procedure, nonsurvival porcine nephrectomies were completed without complications via a single 15-mm transumbilical trocar using a prototype MAGS camera and a magnetically anchored, robotic arm cauterizer.

We report a rare case of a strangulated internal hernia behind the common iliac artery after robot-assisted pelvic lymph node dissection. Internal hernias involving the retroperitoneal vascular axis have been reported four times in medical literature. This is the first time it has been seen after robotic surgery.

Objective. As recent participants in an integrated prostate cancer (PCa) care center, we sought to evaluate whether financial investment in an intensity-modulated radiation therapy (IMRT) center resulted in an increased utilization of radiation therapy in our patients with newly diagnosed PCa. Materials & Methods. Following institutional review board approval, we retrospectively reviewed the records of all consecutive patients who were diagnosed with prostate cancer in the 12 months prior to and after investment in IMRT. Primary treatment modalities included active surveillance (AS), brachytherapy (BT), radiation therapy (XRT), radical prostatectomy (RP), and androgen deprivation therapy (ADT). Treatment data were available for all patients and were compared between the two groups. Results. A total of 344 patients with newly diagnosed PCa were evaluated over the designated time period. The pre-investment group totaled 198 patients, while 146 patients constituted the post-investment group. Among all patients evaluated, there was a similar rate in the use of XRT (20.71% versus 20.55%, ) pre- and post-investment in IMRT. Conclusions. Financial interest in IMRT by urologists does not impact overall utilization rates among patients with newly diagnosed PCa at our center.

Objectives To evaluate whether the use of silver-coated catheters increased the risk of developing urethral stricture disease after robotic-assisted laparoscopic radical prostatectomy (RALP). Recently, silver alloy-coated Foley catheters have been shown to decrease the risk of catheter-associated urinary tract infections. Other than the increased cost, no disadvantages to the use of these catheters have been reported. Material and Methods We switched to routine use of the Bardex I.C. silver alloy-coated Foley catheters for all urologic procedures on November 1, 2008. After institutional review board approval, we retrospectively reviewed the records of all consecutive patients who had undergone RALP 12 months before and after the catheter change. The primary outcome was the rate of urethral strictures after RALP. Results A total of 188 RALPs were performed during the 12 months before the catheter change. No patients who underwent RALP in the months before the catheter change had developed a new postoperative urethral stricture. In the 12 months after the change to the silver-coated catheters, 217 RALPs were performed. Six patients after RALP using silver-coated catheters developed new strictures, at a rate of 2.8% (P = .03). Conclusions Silver alloy-coated urinary catheters might increase the risk of developing urethral strictures after RALP compared with standard noncoated catheters. Additional evaluation by a large randomized prospective trial is warranted to elucidate the true risk of stricture formation.

Renal cysts are the most common renal masses and occur in up to 50% of individuals over the age of 50 years (1,2). Although renal cysts may be either congenital or acquired, most are simple, asymptomatic, and of unknown etiology. Intervention is needed when cysts are determined to be complex by radiographic criteria or when they are associated with pain, infection, hemorrhage, or urinary obstruction. Some congenital diseases such as autosomal dominant polycystic kidney disease (ADPKD), the most common form of renal cystic disease in the United States, are commonly associated with symptomatic cysts (3). Other cystic diseases such as von-Hippel-Lindau (VHL), tuberous sclerosis, multilocular cystic nephroma, and acquired cystic disease have a predisposition toward malignant degeneration. The need for intervention in some cases of symptomatic or suspicious cysts has led to the development of less invasive strategies for renal cyst management (4). This chapter will discuss the role of laparoscopy in evaluation and management of renal cysts.

With the expanding role of laparoscopy in urologic practice, efficient and safe training has become paramount. Virtual reality simulation may potentially aid training, but it requires validation before it can be incorporated into training programs. The objective of this study was to assess whether training on a virtual reality (VR) laparoscopy simulator (LAP Mentor) can improve performance of virtual laparoscopic procedures.After a basic introduction to the LAP Mentor, 32 inexperienced medical students performed a baseline VR cholecystectomy that was observed and scored by two observers using the Objective Structured Assessment of Technical Skills (OSATS). The students were then randomized to two groups: Group 1 trained on the simulator without supervision during a total of six 30-minute sessions, and group 2 received no training. Students were then reevaluated on a second VR cholecystectomy by the same observers.All 32 students completed the study. The two groups were comparable with regard to baseline OSATS scores (group 1, 16.6+/-4.3 v group 2, 15.67+/-6.3, P=0.2). On the second evaluation, the trained students (group 1) performed significantly better than the control group (group 2) (27.9+/-7.2 v 17.6+/-6.2, P0.001). Group 1 students outperformed group 2 students in each category of the OSATS. Moreover, trained students improved their scores by at least 20% (P0.001) in each category, while the untrained students improved only in the "knowledge of procedure" category by 25% (P=0.03).Skills training on a LAP Mentor VR simulator improved VR surgical performance. Before incorporating this simulator into resident education, the LAP Mentor will have to undergo testing for predictive and construct validity.

Virtual reality simulators provide a safe and efficient means of acquiring laparoscopic skills. We evaluated whether training on a virtual reality laparoscopic cholecystectomy simulator (Lap Mentor) improves the performance of a live, unrelated laparoscopic urological procedure.A total of 32 medical students with no previous laparoscopic experience were oriented to the Lap Mentor, and then performed virtual reality laparoscopic cholecystectomy which was assessed by 2 experienced laparoscopists using the previously validated Objective Structured Assessment of Technical Skills scoring. Subjects were randomized to group 1, in which participants completed 6, 30-minute virtual reality training sessions within 3 weeks, or group 2, in which participants received no training. All participants then performed live laparoscopic nephrectomy in a porcine model and performance was evaluated using Objective Structured Assessment of Technical Skills by 2 experts blinded to training status.Mean total pretraining laparoscopic cholecystectomy Objective Structured Assessment of Technical Skills scores were comparable between the groups (16.9 +/- 4.3 for group 1 vs 15.4 +/- 6.2 for group 2, p = 0.4). After training total Objective Structured Assessment of Technical Skills scores for live porcine laparoscopic nephrectomy were significantly higher in group 1 compared to group 2 (21.0 +/- 6.8 vs 15.7 +/- 6.6, respectively, p = 0.03). Likewise, individual subcategory Objective Structured Assessment of Technical Skills scores were higher in group 1 than in group 2, although significant differences were noted only in the categories of instrument handling and knowledge of the procedure.Surgical skills acquired as a result of training on a virtual reality laparoscopic simulator are not procedure specific but improve overall surgical skills, thereby translating into superior performance of an unrelated live laparoscopic urological procedure.

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OBJECTIVE To compare the costs and morbidity of laparoscopic radiofrequency ablation (LRFA) and laparoscopic partial nephrectomy (LPN) for treating small localized renal tumours. PATIENTS AND METHODS We retrospectively analysed the outcomes of 88 patients treated at our institution for a renal tumour either by LPN (50) or LRFA (38) between March 2000 and May 2006. Patients with multiple tumours, combined LRFA and LPN, and those who had other simultaneous surgical procedures were excluded. Clinical variables and outcomes were analysed for each patient. Direct cost data were available for 40 patients treated with LPN and 14 with LRFA. Continuous and categorical variables were compared using an independent t-test and chi-square test, respectively. RESULTS The tumour size was comparable in each group; patients in the LRFA group had more comorbidities (P = 0.01) and a higher overall mortality rate (P = 0.01) but no patient died from cancer. Operative duration, estimated blood loss and length of stay were significantly shorter in the LRFA group but there was no difference in complication rate. LRFA was less costly than LPN ($6103 vs $6808, P = 0.3) but not statistically significantly. The cost savings from the shorter operative duration and length of stay were reduced by the cost of probe. With a median follow-up of 20 months there was no difference in oncological outcome. CONCLUSION Patients undergoing LRFA tend to be older and have more comorbidities than those treated with LPN. The cost is minimally lower for LRFA, secondary to the added cost of the probe. LRFA might be a good alternative treatment in patients at higher risk of surgical complications, but LPN provides good results when done by an experienced surgeon.

To compare the efficacy of conventional and articulating laparoscopic needle-drivers for performing standardized laparoscopic tasks by medical students with no previous surgical experience.Twenty medical students with no surgical experience were randomly assigned to two equal groups, one using a conventional laparoscopic needle-holder (Karl Storz, Tuttlingen, Germany) and the other using a first-generation articulating laparoscopic needle-holder (Cambridge Endo, Framingham, MA, USA). Each student performed a series of four standardized laparoscopic tasks, during which speed and accuracy were assessed. The tasks tested needle passage through rings (1), an oblique running suture model (2), a urethrovesical anastomosis model (3) and a model simulating renal parenchymal reconstruction following partial nephrectomy (4).Tasks 1 and 3 were completed significantly more quickly by those using the conventional instruments (P0.05), but there was no statistically significant difference for task 2 and 4 (P0.05). Those using conventional instruments were significantly more accurate in all of the tasks than those using the articulated instruments (P0.05).The conventional laparoscopic needle-driver allowed laparoscopy-naive medical students to complete a series of standardized suturing tasks more rapidly and accurately than with the novel articulating needle-driver. Laparoscopic suturing with first-generation articulating needle-drivers might be more difficult to learn, secondary to the complexity of physical manoeuvres required for their use.

Optical spectroscopy has been evaluated as an innovative technique for the ex vivo study of renal and prostate tumors. In this pilot study we assessed the ability of optical reflectance spectroscopy to reliably differentiate tumor and normal tissue in renal specimens.From January to April 2007 we completed optical reflectance spectroscopy measurements at several standardized tumor and normal parenchymal locations immediately after kidney tumor removal. The slopes of the optical reflectance spectroscopy curves were compared, and the correlation between tumor and normal parenchyma reflectance was assessed.Reliable measurements were obtained from 13 radical and 8 partial nephrectomy specimens. Histology was malignant in 15 cases (clear cell in 14 and papillary in 1) and benign in 6 cases of oncocytoma. Overall we found a significant difference between the average optical reflectance spectroscopy slopes of tumor and normal parenchyma (p = 0.03). In individual radical nephrectomy specimens optical reflectance spectroscopy measurements at different locations in the tumor showed an excellent correlation (r = 0.968). Normal parenchymal measurements also correlated well (r = 0.88), although there was poor correlation between tumor and nontumor tissue in the specimen (r = 0.07). In the partial nephrectomy subset we also found a close correlation among measurements made on the normal parenchymal margin of the tumor (r = 0.94) except in 1 case of a positive margin (oncocytoma), in which the measurement from the positive margin site did not correlate with that of the adjacent parenchymal margin (r = 0.48).Optical reflectance spectroscopy can help distinguish tumor from normal renal tissue in specimens immediately removed at surgery. Optical reflectance spectroscopy may allow real-time assessment of positive margins during partial nephrectomy.

Natural orifice translumenal endoscopic surgery (NOTES) is an evolving field and suitable instruments are lacking. The purpose of this study was to perform transvaginal cholecystectomies using instruments incorporated into a magnetic anchoring and guidance system (MAGS). Non-survival procedures were conducted in pigs (n = 4). Through a vaginotomy created under direct vision, a rigid access port was inserted into the peritoneal cavity and used to maintain a CO2 pneumoperitoneum. MAGS instruments were deployed through the port and held in place on the peritoneal surface using magnetic coupling via an external handheld magnet which was optionally exchanged for an 18ga percutaneous threaded needle anchor; instruments included a tissue retractor (a clip-fixated magnet or flexible graspers) and a cautery dissector. A gastroscope was used for visualization. The first two procedures ended prematurely due to instrumentation shortcomings and inadvertent magnetic coupling between instruments; one case required a laparoscopic rescue. Three new forms of instrumentation were developed: (1) a longer access port (50 cm) which provided easier deployment of instruments and suitable reach, (2) a more robust cauterizer with a longer, more rigid, pneumatically deployed tip with better reach and sufficient torque to allow blunt dissection, and (3) a more versatile tissue retractor with bidirectional dual flexible graspers which provided excellent cephalad fundus retraction and inferiolateral infundibulum retraction. With these modifications, 100% of the cholecystectomy was completed in the third and fourth animals using only a NOTES/MAGS approach. Retrieval of the tissue retractor resulted in a rectal injury in the third animal but further procedural modifications resulted in a successful procedure in the fourth animal with no complications. While still under development with more refinements needed, completely transvaginal cholecystectomy using MAGS instruments is feasible. By offering triangulation and rigidity, MAGS may facilitate a NOTES approach while alleviating shortcomings of a flexible platform.