A High-Fidelity Phantom for the Simulation and Quantitative Evaluation of Transurethral Resection of the Prostate.

Transurethral resection of the prostate (TURP) is a minimally invasive endoscopic procedure that requires experience and skill of the surgeon. To permit surgical training under realistic conditions we report a novel phantom of the human prostate that can be resected with TURP. The phantom mirrors the anatomy and haptic properties of the gland and permits quantitative evaluation of important surgical performance indicators. Mixtures of soft materials are engineered to mimic the physical properties of the human tissue, including the mechanical strength, the electrical and thermal conductivity, and the appearance under an endoscope. Electrocautery resection of the phantom closely resembles the procedure on human tissue. Ultrasound contrast agent was applied to the central zone, which was not detectable by the surgeon during the surgery but showed high contrast when imaged after the surgery, to serve as a label for the quantitative evaluation of the surgery. Quantitative criteria for performance assessment are established and evaluated by automated image analysis. We present the workflow of a surgical simulation on a prostate phantom followed by quantitative evaluation of the surgical performance. Surgery on the phantom is useful for medical training, and enables the development and testing of endoscopic and minimally invasive surgical instruments.

Thermal effects of Ho:YAG laser lithotripsy during retrograde intrarenal surgery and percutaneous nephrolithotomy in an ex vivo porcine kidney model.

PURPOSE: To evaluate the thermal effect of high-power holmium:yttrium-aluminum-garnet (Ho:YAG) laser lithotripsy in flexible/semirigid ureteroscopy (fURS/sURS) and percutaneous nephrolithotomy (PNL) in a standardized ex vivo porcine kidney model with real-time temperature assessment. METHODS: The experimental setup consisted of three models designed to evaluate the thermal effects of Ho:YAG laser lithotripsy in fURS, sURS and PNL, respectively. In all setups, a postmortem porcine kidney was placed in a 37 °C water bath. Three thermocouples were inserted into the renal parenchyma while a flexible thermocouple was placed 3-4 mm proximal to the laser fiber to measure temperature variations in the collecting system. The thermal impact was evaluated in relation to laser power between 5 and 100 W and various irrigation rates (37 °C, 0-100 ml/min). RESULTS: In all three experimental setups, sufficient irrigation was required to prevent potentially damaging temperatures into the renal pelvis and parenchyma. Even 5 W in fURS can lead to a potentially harming temperature rise if insufficient irrigation is applied. Particularly, high-power settings ≥ 30 W carry an elevated risk for critical temperature rises. The results allow the definition of a specific irrigation threshold for any power setting to prevent critical temperatures in the present study design. CONCLUSIONS: Ho:YAG laser lithotripsy bears the risk of thermal damages to the urinary tract even at low-power settings if inadequate irrigation is applied. Sufficient irrigation is mandatory to perform safe Ho:YAG laser lithotripsy. Based on the results, we developed a formula calculating the approximate ΔT for irrigation rates ≥ 30 ml/min: ΔT = 15 K × (power [W]/irrigation [ml/min]).

[Uro mHealth: health apps in urology]. / Uro mHealth: Gesundheits-Apps in der Urologie.

The use of readily available mHealth apps on smartphones and tablets is increasing worldwide, including the field of urology. Access to knowledge, data collection and communication are thus simplified and accelerated. A wide range of health apps exists for the public, patients, health professionals and medical education. In particular, in the field of urology, several high quality mHealth contents have been created in recent years. Nevertheless, there is still need for improvement and development.The ubiquity of health apps might also bring particular risks. Healthcare professionals can use their private electronic devices when dealing with patients or patient data, and thus risk violations of patient and data protection rights.There are no universal quality standards or legal certification requirements for mHealth apps. Private (mostly commercial) app developers and providers possess quasi-proprietary rights concerning user data. Politics, scientific funding agencies and medical societies are therefore urgently needed to set standards and to promote and fund open-source key projects providing quality benchmarks within the field.

Risk Factors for Ureteral Damage in Ureteroscopic stone Treatment: Results of the German Prospective Multicentre Benchmarks of Ureterorenoscopic Stone Treatment-Results in Terms of Complications, Quality of Life, and Stone-Free Rates Project.

BACKGROUND: The Post-Ureteroscopic Lesion Scale (PULS) is a validated, standardised scale that classifies iatrogenic ureteral lesions during ureteroscopy (URS). OBJECTIVE: To determine risk factors for the various PULS-grades caused by URS. METHOD: We prospectively investigated the independent influence of various risk factors in correlation with PULS-Grade 1+ and 2+ on 307 patients with ureterorenoscopic stone treatment from 14 German urologic departments. RESULTS: The following are the outcomes of the study: 117 (38.4%) and 188 (61.6%) of the calculi (median stone size 6 mm) were found in the kidney or ureter; 70% and 82.4% underwent preoperative or postoperative ureteral stenting; 44.3 and 7.2% received laser or ballistic lithotripsy; 60% of the patients presented with PULS grade 1+ and 8% with PULS grade of 2+. Only intracorporal lithotripsy revealed a significant independent risk factor for PULS grade 1+ or 2+. Both laser and ballistic therapies raised the probability of PULS grade 1+ by the factors 3.6 (p < 0.001) and 3.9 (p = 0.021), respectively. The ORs in conjunction with PULS grade 2+ were 3.1 (p = 0.038) and 5.8 (p = 0.014) respectively. Neither endpoint exhibited a significant difference regarding the lithotripsic procedure (laser vs. ballistic). CONCLUSION: Intracorporal lithotripsy is associated with a significant increase in damage to the ureter; further research is needed to determine its long-term effects.

[Current trends in flexible ureteroscopy: an update]. / Aktuelle Trends in der flexiblen Ureterorenoskopie ­ ein Update.

Flexible ureteroscopy (fURS) has become a success story in urology. Since its implementation into the treatment of urolithiasis, fURS has demonstrated excellent clinical performance and safety. In recent years, the spread of disposable ureteroscopes has shaped the field of endoscopic stone treatment. However, the primary advantage of these devices is that they improve the workflow in urology theatres (no sterilisation, no repair costs) and possibly minimise bacteria transfer in working channels rather than being a real technological "game changer". Novel disruptive improvements such as automatic laser lithotripsy or intrarenal pressure and temperature control in real time are still waiting to enter the clinical routine. These innovations might take fURS to the next level and disruptively change endoscopic stone treatment.