Guideline-adherence in the treatment of symptomatic urolithiasis in children and adolescents in southwestern Germany.

BACKGROUND: Approximately 1% of urolithiasis cases in Germany affect children. Interdisciplinary groups have agreed on national and international guidelines for children to recommend appropriate treatment pathways. The aim of this retrospective and preliminary study is to analyze whether adherence to current guidelines for pediatric stone disease in southwestern Germany is feasible. METHODS: During 2014 to 2017 24 children and adolescents (nine female, 15 male, median age 9.7 years), were treated for symptomatic urolithiasis in our institutions. We retrospectively collected clinical and operative courses. Clinical pathways were compared to previous guideline recommendations of the EAU 2014 and the German S2k guideline 2015. RESULTS: 17 of the 24 patients were treated according to guideline recommendations (71%). Non-adherency was based on parental decisions in two and technical/medical considerations in five cases. In 11 children (45.8%) secondary or adjunctive treatments were necessary, in three of the seven non-adherently treated (43%) and in eight of the 17 adherently treated children (47%). CONCLUSION: Our daily treatment approach seems to comply well with current pediatric stone guidelines. Nevertheless, guideline-non-adherent decision making emphasizes their strength and limitations, as specific clinical situations in children may require an individual treatment plan, as non-predictable conditions may occur.

Visually navigated, ultrasound-guided, freehand percutaneous calyceal puncture - preclinical evaluation of a novel device to simplify a complex surgical task.

Purpose Freehand sonographic percutaneous puncture techniques for the renal calyceal system are on the rise. Much time and practice are required to master this technique. Navigation-supported puncture aids could help make percutaneous access easier and faster. The aim of this study was to determine whether navigated puncture is feasible, and whether it is easier and faster compared to the conventional sonographic procedure. Materials & Methods We performed prospective free-hand percutaneous puncture on a porcine kidney model embedded in gelatin using the Xperius ultrasound system in combination with needle tracking with a Stimuplex Onvision hollow needle, compared to the conventional freehand ultrasound puncture technique. Punctures were performed by 25 participants using the ultrasound machine with or without needle tracking mode. Results Compared to the conventional approach, the navigated approach reduced the number of puncture procedures by 0.2 attempts(8%) in the experienced group. The time to calyx access was reduced by 15 seconds (26%). In the novice group, navigated puncture required 1.2 fewer attempts (36%) and the time to access was 70 seconds faster (61%). Conclusion Puncture using the novel device is feasible. The number of punctures and the time needed for successful access of the calyceal system was reduced by use of navigation in both groups, although the trend was significant only in the novice group. Navigation using needle tracking seems to help beginners perform sonographic percutaneous puncture at a level similar to experienced users. For a more precise analysis and validation, further studies are needed.

[Imaging in nephroureterolithasis]. / Bildgebung bei Nephroureterolithiasis.

In the acute diagnostics of a suspected nephroureterolithiasis, ultrasonography should be the examination modality of choice. In cases of suspected urolithiasis, unclear flank pain with fever or in cases of a solitary kidney, a noncontrast computed tomography (CT) scan should always subsequently be performed. If the sonography findings are inconclusive in pregnant women a magnetic resonance imaging (MRI) examination can be considered. If there are indications for urinary diversion, a retrograde imaging study should be performed as part of the urinary diversion. This or CT imaging is also suitable for preinterventional imaging before shock wave lithotripsy, percutaneous nephrolithotomy or ureteroscopy. Postinterventional imaging is not always necessary and sonography is often sufficient. In a conservative treatment approach an abdominal plain X­ray can be used for follow-up assessment.

[Image-guided biopsy of the prostate gland]. / Bildgesteuerte Biopsie der Prostata.

The recommendations on carrying out a multiparametric magnetic resonance imaging (mpMRI) for the primary diagnostics and during active surveillance of prostate cancer, include as a consequence an image-guided sampling from conspicuous areas. In doing so, the information on the localization provided by mpMRI is used for a targeted biopsy of the area suspected of being a tumor. The targeted sampling is mainly performed under sonographic control and after fusion of MRI and ultrasound but can also be (mostly in special cases) carried out directly in the MRI scanner. In an ultrasound-guided biopsy, it is vital to coregister the MR images with the ultrasound images (segmentation of the contour of the prostate and registration of suspect findings). This coregistration can either be carried out cognitively (transfer by the person performing the biopsy alone) or software based. Each method shows specific advantages and disadvantages in the prioritization between diagnostic accuracy and resource expenditure.

[Lasers in urology : Relevant principles]. / Laser in der Urologie : Relevante Grundlagen.

A fundamental understanding of the physical properties is necessary for the application of lasers in medicine in order to be able to understand and appreciate the biological effect. The most important parameters are emission mode, wavelength of the laser and power output measured in watts. Pulsed lasers can be used for the treatment of stones and soft tissues, whereby in urology this essentially applies to the prostate gland and to a lesser extent also for the ureter, urethra, bladder and kidneys.

Cryobiopsy in the Upper Urinary Tract: Preclinical Evaluation of a Novel Device.

OBJECTIVE: To develop a novel device for cryobiopsy of the upper urinary tract (UUT) and to evaluate its feasibility in a standardized preclinical setting. MATERIALS AND METHODS: Flexible cryoprobes (diameter 0.9 mm; cooling agent CO2) were developed and used to extract biopsies in porcine UUTs. Cryosamples obtained by ureterorenoscopy were systematically compared with biopsy specimens obtained with standard of care devices in terms of physical characteristics (deflection angle and irrigation flow rates) and histologic criteria (assessability). RESULTS: Irrigation flow rates were significantly higher with introduced BIGopsy (2.8 ± 0.1) compared with standard forceps (0.94 ± 0.06; P < .001) and cryoprobe (1.1 ± 0.1; P < .001). Angular deflection was significantly reduced by the inserted cryoprobe (130.7° ± 1.2° vs 166.9° ± 1.1° [BIGopsy] or 161.4° ± 1.9° [standard forceps]; both P < .001). Significantly larger UUT tissue samples were obtained by the cryoprobe (mean specimen area 7.5 ± 2.5 vs 4.6 ± 2.5 mm² [BIGopsy] or 1.4 ± 1.4 mm² [standard forceps]; both P < .001). No crush artifacts were observed in cryosamples. Superior histologic assessability scores were achieved in samples obtained by the cryoprobe (mean 2.8 ± 0.8) and BIGopsy (2.3 ± 1.9) when compared with standard forceps (0.4 ± 0.9; P < .001). CONCLUSION: Cryobiopsy in the UUT is feasible and represents a viable new option to improve the diagnostic accuracy of histopathologic evaluation. Larger and more representative tissue samples can be obtained using a cryoprobe and artifacts may be avoided. Further optimization of the probe will reduce possible restrictions of ureterorenoscopy handling when the device is inserted.

Validation of a Novel Cost Effective Easy to Produce and Durable In Vitro Model for Kidney-Puncture and Percutaneous Nephrolitholapaxy-Simulation.

INTRODUCTION: Nephrolithiasis is one of the most common diseases in urology. According to the EAU Guidelines, a percutaneous nephrolitholapaxy (PNL) is recommended when treating a kidney stone >2 cm. Nowadays, PNL is performed even for smaller stones (<1 cm) using miniaturized instruments. The most challenging part of any PNL is the puncture of the planned site. PNL-novice surgeons need to practice this step in a safe environment with an ideal training model. We developed and evaluated a new, easy to produce, in vitro model for the training of the freehand puncture of the kidney. MATERIALS AND METHODS: Porcine kidneys with ureters were embedded in ballistic gel. Food coloring and preservative agent were added. We used the standard imaging modalities of X-ray and ultrasound to validate the training model. An additional new technique, the iPAD-guided puncture, was evaluated. Five novices and three experts conducted 12 punctures for each imaging technique. Puncture time, radiation dose, and number of attempts to a successful puncture were measured. Mann-Whitney-U, Kruskal-Wallis, and U-Tests were used for statistical analyses. RESULTS: The sonography-guided puncture is slightly but not significantly faster than the fluoroscopy-guided puncture and the iPAD-assisted puncture. Similarly, the most experienced surgeon's time for a successful puncture was slightly less than that of the residents, and the experienced surgeons needed the least attempts to perform a successful puncture. In terms of radiation exposure, the residents had a significant reduction of radiation exposure compared to the experienced surgeons. CONCLUSION: The newly developed ballistic gel kidney-puncture model is a good training tool for a variety of kidney-puncture techniques, with good content, construct, and face validity.

[The future of laparoscopy and robotics in urology]. / Zukunft der Laparoskopie und Robotik in der Urologie.

The introduction of robotics led to a decrease in the importance of classical laparoscopy. Nevertheless laparoscopy and retroperitoneoscopy underwent significant technological improvements during the last decade, including introduction of 4k Ultra HD video technology, 3D-HD-videosystems, minaturised instruments, advanced sealing devices, instruments with 7 degrees of freedom, and ergonomic platforms Ethos Chair®. The monopoly of robotic surgical devices will end in 2019, because key patents of Intuitive Surgical will expire. This will lead to an interesing competition among new manufacturers of robotic surgical devices, which however have to prove that they meet the high quality standard of the current da Vinci series, such as type of console, arrangement of robotic arms, technology of 3D-videosystem, and quality and degrees of freedom of end effectors. There are also robotic systems used in endourology: Avicenna Roboflex® and the AquaBeam®-System for robot-assisted aquablation therapy of the prostate. While Roboflex improves the ergonomics of flexbile ureteroscopy, AquaBeam may for the first time eliminate the surgeon.

Robot-assisted flexible ureteroscopy: an update.

The role of flexible ureteroscopy (FURS) in the management of nephrolithiasis has increased due to the improved armamentarium. However, FURS still represents a challenging technique limiting its diffusion. Similar to previous experiences in laparoscopy, recently developed robotic devices may significantly compensate for the ergonomic deficiencies of FURS. Based on a short description of the history of robotic devices for laparoscopy, this article summarizes all current developments of robotic FURS. In 2008, robotic FURS was first reported using the Sensei-Magellan system designed for interventional cardiology. However, with this device the ureteroscope was only passively manipulated, which represented the main reason why this project has been discontinued after 18 clinical cases. Avicenna Roboflex™ was especially developed for FURS. It consists of a surgeon's console and manipulator of a flexible ureterorenoscope. The console provides an adjustable seat with armrests and two manipulators of the endoscope: the right wheel enables deflection and the left horizontal joystick allows rotation as well as advancing and retracting the instrument. The speed of rotation and advancement can be regulated at the screen of the console. Using the IDEAL system for evaluation of new robotic devices, safety and efficacy of the system could be demonstrated in two multi-centric studies providing significant improved ergonomics for the surgeon (IDEAL stage 1 and 2). Future studies are necessary to determine the final role of robotic FURS.