Characterization of Flow-Caused Intrarenal Pressure Conditions During Percutaneous Nephrolithotomy In Vitro.

PURPOSE: To investigate renal pelvic pressures during percutaneous nephrolithotomy (PCNL) in the standard, mini, and ultramini PCNL systems. METHODS: We studied an ultramini PCNL system (UMP, outer shaft diameter 13F), a mini PCNL system (MPCNL, shaft 18F, nephroscope 12F), and a standard PCNL system (SPCNL, shaft 27F, nephroscope 24F). Pressure profiles were first investigated in an open model setup, subsequently in a closed model, and finally in an ex vivo porcine kidney. Measurements were determined with the nephroscope in an advanced and pulled-back position for all models. RESULTS: In the advanced position, maximum pressures of 41.61 ± 0.20 mmHg (UMP), 15.61 ± 0.15 mmHg (MPCNL), and 15.46 ± 0.14 mmHg (SPCNL) were measured in the closed model. In the pulled-back position, maximum pressures were 16.04 ± 0.22 mmHg (UMP), 17.02 ± 0.11 mmHg (MPCNL), and 20.50 ± 0.11 mmHg (SPCNL). In the ex vivo porcine kidney model, maximum pressures were 13.81 ± 6.04 mmHg (UMP), 5.64 ± 0.21 (MPCNL), and 9.21 ± 0.52 (SPCNL) with the nephroscope pushed to end position. After retracting the nephroscope from the outer shaft, pressures in all systems did not exceed 10 mmHg. CONCLUSIONS: The maximum pressures achieved with the three PCNL systems in all three models were kept below the 30 mmHg critical threshold value. High pressures were only determined for the UMP system with the nephroscope pushed to its end position. This was attributed to the conical shape of the nephroscope, which occupies the space between the nephroscope and outer shaft, resulting in outflow obstruction.

Robotic waterjet wound debridement - Workflow adaption for clinical application and systematic evaluation of a novel technology.

OBJECTIVE: We evaluated the clinical potential of a novel robotic system for autonomous performance of waterjet wound debridement. SUMMARY BACKGROUND DATA: Within the last decade, waterjet wound debridement has proven to be a valid alternative to the conventional approach using sharp spoons and scalpel. METHODS: The DLR MIRO robot using the DLR MICA instrument for robotic surgery was adapted for actuation of an ERBEJET 2 flexible endoscopic waterjet probe. Waterjet debridement of various wound shapes and sizes using a porcine skin model was compared between this novel robotic system and a control group of human medical professionals with regard to wound area cleaned by the waterjet, off-target area, and procedural time. RESULTS: After the wound area was registered in the robotic system, it automatically generated a cleaning path and performed debridement based on generated surface model. While the robotic system demonstrated a significant advantage for the covered wound area (p = 0.031), the average off-target area was not significantly different from human controls. Human participants had high variability in cleaning quality across users and trials, while the robotic system provided stable results. Overall procedural time was significantly lower in trials performed by humans. CONCLUSIONS: Robotic waterjet wound debridement is a promising new technological approach compared to the current clinical standard of interventional wound therapy, providing higher efficiency and quality of wound cleaning compared to human performance. Additional trials on more complicated wound shapes and in vivo tissue are necessary to more thoroughly evaluate the clinical potential of this technology.

Robotic stone surgery - Current state and future prospects: A systematic review.

OBJECTIVE: To provide a comprehensive review of robot-assisted surgery in urolithiasis and to consider the future prospects of robotic approaches in stone surgery. MATERIALS AND METHODS: We performed a systematic PubMed© literature search using predefined Medical Subject Headings search terms to identify PubMed-listed clinical research studies on robotic stone surgery. All authors screened the results for eligibility and two independent reviewers performed the data extraction. RESULTS: The most common approach in robotic stone surgery is a robot-assisted pyelolithotomy using the da Vinci™ system (Intuitive Surgical Inc., Sunnyvale, CA, USA). Several studies show this technique to be comparable to classic laparoscopic and open surgical interventions. One study that focused on ureteric stones showed a similar result. In recent years, promising data on robotic intrarenal surgery have been reported (Roboflex Avicenna™; Elmed Medical Systems, Ankara, Turkey). Initial studies have shown its feasibility and high stone-free rates and prove that this novel endoscopic approach is safe for the patient and comfortable for the surgeon. CONCLUSIONS: The benefits of robotic devices in stone surgery in existing endourological, laparoscopic, and open treatment strategies still need elucidation. Although recent data are promising, more prospective randomised controlled studies are necessary to clarify the impact of this technique on patient safety and stone-free rates.

A new type of microglia gene targeting shows TAK1 to be pivotal in CNS autoimmune inflammation.

Microglia are brain macrophages and, as such, key immune-competent cells that can respond to environmental changes. Understanding the mechanisms of microglia-specific responses during pathologies is hence vital for reducing disease burden. The definition of microglial functions has so far been hampered by the lack of genetic in vivo approaches that allow discrimination of microglia from closely related peripheral macrophage populations in the body. Here we introduce a mouse experimental system that specifically targets microglia to examine the role of a mitogen-associated protein kinase kinase kinase (MAP3K), transforming growth factor (TGF)-ß-activated kinase 1 (TAK1), during autoimmune inflammation. Conditional depletion of TAK1 in microglia only, not in neuroectodermal cells, suppressed disease, significantly reduced CNS inflammation and diminished axonal and myelin damage by cell-autonomous inhibition of the NF-κB, JNK and ERK1/2 pathways. Thus, we found TAK1 to be pivotal in CNS autoimmunity, and we present a tool for future investigations of microglial function in the CNS.