The relationship between the force applied and perceived by the surgeon during ureteral access sheath placement: ex-vivo experimental model.

PURPOSE: To define a peak force of insertion (PFOI) threshold for ureteral damage during ureteral access sheath (UAS) placement on an experimental ureteral orifice model. METHODS: A specially designed water tank using 2 laparoscopic 5 mm ports and 2 different size (10 Fr and 8 Fr) sealing cap adaptors (SCA) as ureteral orifices was used to perform the test. A 10-12 Fr UAS was fixed to a load cell and the force of insertion (FOI) was continuously recorded with a digital force gauge.13 experts in the field of endourology who participated performed 3 UAS insertions. The FOI was recorded initially with 10 Fr followed by 8 Fr SCA. On the final insertion, the orifice was obstructed, leaving a 5 cm length to insert the UAS. The experts were asked to "Stop at the point they anticipate ureteral damage, and they would not proceed in real life". RESULTS: Using 10 Fr SCA the PFOI was 2.12 ± 0.58 Newton (N) (range:1.48-3.48) while 8 Fr SCA showed a PFOI 5.76 ± 0.96 N (range:4.05-7.35). Six of the experts, said they would stop proceeding when they reached above 5.1 N. Three experts had PFOI < 5.1 N and the other 4 stated they would go with PFOIs of 5.88, 6.16, 6.69 and 7.35 N when using SCA of 8 Fr.The highest load they would stop proceeding had a PFOI of 6.09 ± 1.87 N (range: 2.53-10.74). CONCLUSION: The PFOI threshold for ureteral damage inserting UAS of the experts is variable. Although FOI is a subjective perception, experience suggests that ureteral injury may occur at an average of 6.05 N perceived by surgeons' tactile feedback. In-vivo measurement of UAS PFOI may confirm a threshold.

Time-resolving state-specific molecular dissociation with XUV broadband absorption spectroscopy.

The electronic and nuclear dynamics inside molecules are essential for chemical reactions, where different pathways typically unfold on ultrafast timescales. Extreme ultraviolet (XUV) light pulses generated by free-electron lasers (FELs) allow atomic-site and electronic-state selectivity, triggering specific molecular dynamics while providing femtosecond resolution. Yet, time-resolved experiments are either blind to neutral fragments or limited by the spectral bandwidth of FEL pulses. Here, we combine a broadband XUV probe pulse from high-order harmonic generation with an FEL pump pulse to observe dissociation pathways leading to fragments in different quantum states. We temporally resolve the dissociation of a specific O2+ state into two competing channels by measuring the resonances of ionic and neutral fragments. This scheme can be applied to investigate convoluted dynamics in larger molecules relevant to diverse science fields.

International Alliance of Urolithiasis (IAU) guidelines on the metabolic evaluation and medical management of urolithiasis.

The aim of this study was to construct the fourth in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis (IAU) that by providing a clinical framework for the metabolic evaluation, prevention, and follow-up of patients with urolithiasis based on the best available published literature. All recommendations were summarized following a systematic review and assessment of the literature in the PubMed database from January 1976 to June 2022. Each generated recommendation was graded using a modified GRADE methodology. Guideline recommendations were developed that addressed the following topics: initial evaluation, metabolic testing, dietary measures, medical management, and follow-up of recurrent stone formers. It was emphasized by the Panel that prevention of new stone formation is as important as the surgical removal of the stones. Although general preventive measures may be effective in reducing stone recurrence rates in some patients, specific medical and dietary management should be well considered and eventually applied in an individualized manner based on the outcomes of metabolic work-up, stone analysis and some certain patient related factors. A detailed follow-up of each case is essential depending on the metabolic activity of each individual patient.

Differential Measurement of Electron Ejection after Two-Photon Two-Electron Excitation of Helium.

We report the measurement of the photoelectron angular distribution of two-photon single-ionization near the 2p^{2} ^{1}D^{e} double-excitation resonance in helium, benchmarking the fundamental nonlinear interaction of two photons with two correlated electrons. This observation is enabled by the unique combination of intense extreme ultraviolet pulses, delivered at the high-repetition-rate free-electron laser in Hamburg (FLASH), ionizing a jet of cryogenically cooled helium atoms in a reaction microscope. The spectral structure of the intense self-amplified spontaneous emission free-electron laser pulses has been resolved on a single-shot level to allow for post selection of pulses, leading to an enhanced spectral resolution, and introducing a new experimental method. The measured angular distribution is directly compared to state-of-the-art theory based on multichannel quantum defect theory and the streamlined R-matrix method. These results and experimental methodology open a promising route for exploring fundamental interactions of few photons with few electrons in general.

Paediatric stone management: innovations and standards.

PURPOSE OF REVIEW: The aim of this study was to discuss current trends and recent developments in the surgical management of paediatric urolithiasis. RECENT FINDINGS: Medical expulsive therapy (MET) is considered as an option for the treatment of children with ureter stones. Extracorporeal shockwave lithotripsy (SWL) remains as a first option for majority of kidney stones and upper ureter stones. Advances in endourology have led to increased adoption of retrograde intrarenal surgeries (RIRS) and percutaneous nephrolithotomy (PCNL/mini-PCNL/ultra-mini-PCNL/micro-PCNL). SUMMARY: Management of paediatric stone disease has developed significantly in the past decade. However, the evidence in the literature remains disproportional to these advances. Well designed multicentric studies are still needed to compare effectiveness and safety of these procedures.

European Association of Urology Section of Urolithiasis and International Alliance of Urolithiasis Joint Consensus on Percutaneous Nephrolithotomy.

CONTEXT: Although percutaneous nephrolithotomy (PCNL) has been performed for decades and has gone through many refinements, there are still concerns regarding its more widespread utilization because of the long learning curve and the potential risk of severe complications. Many technical details are not included in the guidelines because of their nature and research protocol. OBJECTIVE: To achieve an expert consensus viewpoint on PCNL indications, preoperative patient preparation, surgical strategy, management and prevention of severe complications, postoperative management, and follow-up. EVIDENCE ACQUISITION: An international panel of experts from the Urolithiasis Section of the European Association of Urology, International Alliance of Urolithiasis, and other urology associations was enrolled, and a prospectively conducted study, incorporating literature review, discussion on research gaps (RGs), and questionnaires and following data analysis, was performed to reach a consensus on PCNL. EVIDENCE SYNTHESIS: The expert panel consisted of 36 specialists in PCNL from 20 countries all around the world. A consensus on PCNL was developed. The expert panel was not as large as expected, and the discussion on RGs did not bring in more supportive evidence in the present consensus. CONCLUSIONS: Adequate preoperative preparation, especially elimination of urinary tract infection prior to PCNL, accurate puncture with guidance of fluoroscopy and/or ultrasonography or a combination, keeping a low intrarenal pressure, and shortening of operation time during PCNL are important technical requirements to ensure safety and efficiency in PCNL. PATIENT SUMMARY: Percutaneous nephrolithotomy (PCNL) has been a well-established procedure for the management of upper urinary tract stones. However, according to an expert panel consensus, core technical aspects, as well as the urologist's experience, are critical to the safety and effectiveness of PCNL.

[Transurethral resection of the urinary bladder : Status quo and outlook on new developments]. / Transurethrale Resektion der Harnblase : Was ist Standard, was kommt?

BACKGROUND: Transurethral resection of the urinary bladder (TURB) is the standard intervention in the diagnostic workup and treatment of non-muscle invasive bladder cancer. In order to minimize cancer recurrence and potential complications, continuous technical development of TURB is of high clinical interest. OBJECTIVES: Presentation of the current standards and discussion of technological changes. MATERIALS AND METHODS: Analysis of the current guideline recommendations and literature research. RESULTS: The limitations of classic monopolar TURB is supplemented by new resection methods (en bloc) and technologies (bipolar and laser resection). Along with improved visualization through partially established technologies of photodynamic and digital image enhancement, there is potential for optimization regarding the likelihood of recurrences and complications as well as the histological quality of the resected material. CONCLUSION: A positive impact on the oncological value and safety of TURB seems possible through the use of modern technologies. Further establishment up to evidence-based guideline recommendations are necessary.

Consultation on kidney stones, Copenhagen 2019: lithotripsy in percutaneous nephrolithotomy.

PURPOSE: To evaluate the balance between existing evidence and expert opinions on the safety and efficacy of new technological improvements in lithotripsy techniques for percutaneous nephrolithotomy (PCNL). METHODS: A scoping review approach was applied to search literature in Pubmed, Embase, and Web of Science. Consensus by key opinion leaders was reached at a 2-day meeting entitled "Consultation on Kidney Stones: Aspects of Intracorporeal Lithotripsy" held in Copenhagen, Denmark, in September 2019. RESULTS: New-generation dual-mode single-probe lithotripsy devices have shown favourable results compared with use of ballistic or ultrasonic lithotripters only. However, ballistic and ultrasonic lithotripters are also highly effective and safe and have been the backbone of PCNL for many years. Compared with standard PCNL, it seems that mini PCNL is associated with fewer bleeding complications and shorter hospital admissions, but also with longer operating room (OR) time and higher intrarenal pressure. Use of laser lithotripsy combined with suction in mini PCNL is a promising alternative that may improve such PCNL by shortening OR times. Furthermore, supine PCNL is a good alternative, especially in cases with complex renal stones and large proximal ureteric stones; in addition, it facilitates endoscopic combined intrarenal surgery (ECIRS). CONCLUSION: Recent technological improvements in PCNL techniques are promising, but there is a lack of high-level evidence on safety and efficacy. Different techniques suit different types of stones and patients. The evolution of diverse methods has given urologists the possibility of a personalized stone approach, in other words, the right approach for the right patient.

Consultation on UTUC, Stockholm 2018: aspects of treatment.

PURPOSE: To provide an overview of treatment modalities for management of upper tract urothelial carcinoma (UTUC). METHODS: In accordance with the standards for a scoping review, data presentation and discussion at the Consultation on UTUC in Stockholm, 6-7 September 2018, consensus was reached on the latest and most important treatment recommendations for UTUC. Using Pubmed, Web of Science, and Embase, publications were selected based on quality, clinical relevance, and level of evidence. RESULTS: Kidney-sparing surgery should be attempted for low-grade UTUC. Radical nephroureterectomy with bladder cuff excision is first option for high-grade disease. Post-operative bladder instillation of chemotherapy should be offered after RNU to reduce intravesical recurrence rate. Identification of tumor grade and stage is crucial when selecting treatment. Ureteroscopic management of low-grade and non-invasive UTUC achieves disease-free survival similar to that offered by radical nephroureterectomy but seems to be a risk factor for intravesical recurrence. Lymphadenectomy appears important for high-risk disease, although the therapeutic benefit needs further validation. There is little evidence supporting use of Bacillus Calmette-Guérin (BCG) and mitomycin C as monotherapy and adjuvant treatment in UTUC. A randomized clinical trial has indicated that platin-based chemotherapy for invasive UTUC improves disease-free survival, suggesting that adjuvant chemotherapy should be considered standard care for ≥ T2 N0-3M0 disease. CONCLUSIONS: Risk stratification assessment is feasible and mandatory in UTUC. Identification of tumor grade and stage is essential for optimal treatment selection. Kidney-sparing surgery should be offered in low-risk disease, whereas radical nephroureterectomy and adjuvant chemotherapy should be considered in high-risk disease.

Consultation on UTUC, Stockholm 2018 aspects of risk stratification: long-term results and follow-up.

PURPOSE: To summarize current knowledge on upper urinary tract carcinoma (UTUC) regarding risk stratification, long-term results, and follow-up. METHODS: A scoping review approach was applied to search literature in Pubmed, Web of Science, and Embase. Consensus was reached through discussions at Consultation on UTUC, September 2018, Stockholm. RESULTS: To optimize oncological outcome considering both cancer-specific survival (CSS) and overall survival (OS), it is essential to identify pre- and postoperative prognostic factors. In low-risk UTUC, kidney-sparing surgery (KSS) and radical nephroureterectomy (RNU) offer equivalent CSS, whereas RNU may result in poorer OS due to nephron loss. For more aggressive tumours, undergrading can lead to insufficient treatment. The strongest prognostic factors are tumour stage and grade. Determining grade is best achieved by ureterorenoscopy (URS) with focal samples, biopsy and cytology. Staging is more difficult but can be indirectly achieved by multiphase computed tomography urography (CTU) or tumour grade determined by cytology and histopathology. Patients treated with KSS should be monitored closely with regular follow-ups (URS and CTU). CONCLUSION: KSS should be offered in low-risk UTUC when feasible, whereas RNU is the treatment of choice in organ-confined high-risk UTUC. Intravesical recurrence (IVR) is common after RNU, but a single postoperative dose of mitomycin instillation decreases IVR. Endourological management has high local and bladder recurrence rates; however, its effect on CSS or overall survival OS is unclear. RNU is associated with significant risk of chronic kidney disease. Careful selection of patients and risk stratification are mandatory, and patients should be followed according to strict protocols.

What are the Benefits and Harms of Ureteroscopy Compared with Shock-wave Lithotripsy in the Treatment of Upper Ureteral Stones? A Systematic Review.

CONTEXT: Extracorporeal shock wave lithotripsy (SWL) and ureteroscopy (URS), with or without intracorporeal lithotripsy, are the most common treatments for upper ureteric stones. With advances in technology, it is unclear which treatment is most effective and/or safest. OBJECTIVE: To systematically review literature reporting benefits and harms of SWL and URS in the management of upper ureteric stones. EVIDENCE ACQUISITION: Databases including Medline, Embase, and the Cochrane library were searched from January 2000 to November 2014. All randomised controlled trials (RCTs), quasi-randomised controlled trials, and nonrandomised studies comparing any subtype or variation of URS and SWL were included. The primary benefit outcome was stone-free rate (SFR). The primary harm outcome was complications. Secondary outcomes included retreatment rate, need for secondary, and/or adjunctive procedures. The Cochrane risk of bias tool was used to assess RCTs, and an extended version was used to assess nonrandomised studies. Grading of Recommendations Assessment, Development, and Evaluation was used to assess the quality of evidence. EVIDENCE SYNTHESIS: Five thousand-three hundred and eighty abstracts and 387 full-text articles were screened. Forty-seven studies met inclusion criteria; 19 (39.6%) were RCTs. No studies on children met inclusion criteria. URS and SWL were compared in 22 studies (4 RCTs, 1 quasi-randomised controlled trial, and 17 nonrandomised studies). Meta-analyses were inappropriate due to data heterogeneity. SFR favoured URS in 9/22 studies. Retreatment rates were higher for SWL compared with URS in all studies but one. Longer hospital stay and adjunctive procedures (most commonly the insertion of a JJ stent) were more common when primary treatment was URS. Complications were reported in 11 out of 22 studies. In eight studies, it was possible to report this as a Clavien-Dindo Grade. Higher complication rates across all grades were reported for URS compared with SWL. For intragroup (intra-SWL and intra-URS) comparative studies, 25 met the inclusion criteria. These studies varied greatly in outcomes measured with data being heterogeneous. CONCLUSIONS: Compared with SWL, URS was associated with a significantly greater SFR up to 4 wk but the difference was not significant at 3 mo in the included studies. URS was associated with fewer retreatments and need for secondary procedures, but with a higher need for adjunctive procedures, greater complication rates, and longer hospital stay. PATIENT SUMMARY: In this paper, the relative benefits and harms of the two most commonly offered treatment options for urinary stones located in the upper ureter were reviewed. We found that both treatments are safe and effective options that should be offered based on individual patient circumstances and preferences.

Tract Sizes in Miniaturized Percutaneous Nephrolithotomy: A Systematic Review from the European Association of Urology Urolithiasis Guidelines Panel.

CONTEXT: Miniaturized instruments for percutaneous nephrolithotomy (PNL), utilizing tracts sized ≤22 Fr, have been developed in an effort to reduce the morbidity and increase the efficiency of stone removal compared with standard PNL (>22 Fr). OBJECTIVE: We systematically reviewed all available evidence on the efficacy and safety of miniaturized PNL for removing renal calculi. EVIDENCE ACQUISITION: The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement. Since it was not possible to perform a meta-analysis, the data were summarized in a narrative synthesis. EVIDENCE SYNTHESIS: After screening 2945 abstracts, 18 studies were included (two randomized controlled trials [RCTs], six nonrandomized comparative studies, and 10 case series). Thirteen studies were full-text articles and five were only available as congress abstracts. The size of tracts used in miniaturized procedures ranged from 22 Fr to 4.8 Fr. The largest mean stone size treated using small instruments was 980mm2. Stone-free rates were comparable in miniaturized and standard PNL procedures. Procedures performed with small instruments tended to be associated with significantly lower blood loss, while the procedure duration tended to be significantly longer. Other complications were not notably different between PNL types. Study designs and populations were heterogeneous. Study limitations included selection and outcome reporting bias, as well as a lack of information on relevant confounding factors. CONCLUSIONS: The studies suggest that miniaturized PNL is at least as efficacious and safe as standard PNL for the removal of renal calculi. However, the quality of the evidence was poor, drawn mainly from small studies, the majority of which were single-arm case series, and only two of which were RCTs. Furthermore, the tract sizes used and types of stones treated were heterogeneous. Hence, the risks of bias and confounding were high, highlighting the need for more reliable data from RCTs. PATIENT SUMMARY: Removing kidney stones via percutaneous nephrolithotomy (PNL) using smaller sized instruments (mini-PNL) appears to be as effective and safe as using larger (traditional) instruments, but more clinical research is needed.

First clinical evaluation of a new single-use flexible cystoscope dedicated to double-J stent removal (Isiris™): a European prospective multicenter study.

PURPOSE: We evaluated a new single-use digital flexible cystoscope with an integrated grasper designed for double-J stent removal, Isiris™, addressing success rate, image quality, deflection, maneuverability and grasper functionality. METHODS: In September 2015, a prospective cohort study was conducted in six tertiary European reference centers. All consecutive patients included underwent double-J stent removal and were 18 years or older. Success rate was defined by complete stent removal. Image quality, deflection, maneuverability and grasper functionality were rated with a Likert scale. RESULTS: A total of 83 procedures were performed. 82% of procedures were performed in the endoscopy room, while the others were in the operating room since a consecutive endourological intervention was planned. The median duration of stent implantation was 28 days [14; 60]. In five patients, stent removal was not possible. Four patients had an incrusted double-J stent, and in one patient, the stent migrated into the ureter. After unsuccessful attempts of stent removal with conventional flexible cystoscope and grasper, the five patients had to be scheduled for an ureterorenoscopy procedure to remove the stent. In the other 78 patients, all double-J stents were removed successfully. Image quality, deflection, maneuverability and grasper functionality were rated as "very good" in 72.3, 78.3, 72.3 and 73.5%, respectively. CONCLUSION: This multicenter clinical evaluation of Isiris™ displayed good image quality, active deflection, maneuverability and grasper functionality. Further evaluation of stent removal outcomes, cost analysis and microbiology will help to delineate the possible place of Isiris™ in the current practice.

EAU Guidelines on Diagnosis and Conservative Management of Urolithiasis.

CONTEXT: Low-dose computed tomography (CT) has become the first choice for detection of ureteral calculi. Conservative observational management of renal stones is possible, although the availability of minimally invasive treatment often leads to active treatment. Acute renal colic due to ureteral stone obstruction is an emergency that requires immediate pain management. Medical expulsive therapy (MET) for ureteral stones can support spontaneous passage in the absence of complicating factors. These guidelines summarise current recommendations for imaging, pain management, conservative treatment, and MET for renal and ureteral stones. Oral chemolysis is an option for uric acid stones. OBJECTIVE: To evaluate the optimal measures for diagnosis and conservative and medical treatment of urolithiasis. EVIDENCE ACQUISITION: Several databases were searched for studies on imaging, pain management, observation, and MET for urolithiasis, with particular attention to the level of evidence. EVIDENCE SYNTHESIS: Most patients with urolithiasis present with typical colic symptoms, but stones in the renal calices remain asymptomatic. Routine evaluation includes ultrasound imaging as the first-line modality. In acute disease, low-dose CT is the method of choice. Ureteral stones <6mm can pass spontaneously in well-controlled patients. Sufficient pain management is mandatory in acute renal colic. MET, usually with α-receptor antagonists, facilitates stone passage and reduces the need for analgesia. Contrast imaging is advised for accurate determination of the renal anatomy. Asymptomatic calyceal stones may be observed via active surveillance. CONCLUSIONS: Diagnosis, observational management, and medical treatment of urinary calculi are routine measures. Diagnosis is rapid using low-dose CT. However, radiation exposure is a limitation. Active treatment might not be necessary, especially for stones in the lower pole. MET is recommended to support spontaneous stone expulsion. PATIENT SUMMARY: For stones in the lower pole of the kidney, treatment may be postponed if there are no complaints. Pharmacological treatment may promote spontaneous stone passage.

EAU Guidelines on Interventional Treatment for Urolithiasis.

CONTEXT: Management of urinary stones is a major issue for most urologists. Treatment modalities are minimally invasive and include extracorporeal shockwave lithotripsy (SWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PNL). Technological advances and changing treatment patterns have had an impact on current treatment recommendations, which have clearly shifted towards endourologic procedures. These guidelines describe recent recommendations on treatment indications and the choice of modality for ureteral and renal calculi. OBJECTIVE: To evaluate the optimal measures for treatment of urinary stone disease. EVIDENCE ACQUISITION: Several databases were searched to identify studies on interventional treatment of urolithiasis, with special attention to the level of evidence. EVIDENCE SYNTHESIS: Treatment decisions are made individually according to stone size, location, and (if known) composition, as well as patient preference and local expertise. Treatment recommendations have shifted to endourologic procedures such as URS and PNL, and SWL has lost its place as the first-line modality for many indications despite its proven efficacy. Open and laparoscopic techniques are restricted to limited indications. Best clinical practice standards have been established for all treatments, making all options minimally invasive with low complication rates. CONCLUSION: Active treatment of urolithiasis is currently a minimally invasive intervention, with preference for endourologic techniques. PATIENT SUMMARY: For active removal of stones from the kidney or ureter, technological advances have made it possible to use less invasive surgical techniques. These interventions are safe and are generally associated with shorter recovery times and less discomfort for the patient.

Human papilloma virus is not detectable in samples of urothelial bladder cancer in a central European population: a prospective translational study.

BACKGROUND: Previous investigations on the association of human papillomavirus (HPV) and human bladder cancer have led to conflicting results. The aim of this study was to determine if low and high risk HPV play a role in the etiology of superficial low grade and invasive high grade urothelial carcinoma of the bladder. METHODS: We prospectively collected tumor samples of urothelial carcinoma of the bladder from 109 patients treated with transurethral resection or cystectomy, with bladder tissue from transurethral resection of the prostate serving as control. Unfixed, frozen tumor samples were analyzed for the presence of 14 high risk HPV types using real time PCR. Additionally, all specimens were tested for 35 low risk HPV types with a conventional PCR using degenerate primers located in the L1 region. Six frozen samples of cervical carcinoma served as positive controls. RESULTS: We included 109 cases of bladder cancer with 41 superficial (pTa low grade) tumors, 56 invasive (pT1-T4) high grade tumors and 12 others (pTa high grade + pTis). We have not detected HPV-DNA in any sample (95 % Confidence Interval [CI] 0-3.3 %), superficial tumors (95 % CI 0-6.4 %) or in invasive tumors (95 % CI 0-8.6 %) with correct positive controls. CONCLUSIONS: Using a broad, sensitive assay with prospectively collected specimens of a Central European population we could not detect HPV-DNA in any of the cases. Our results suggest that it is unlikely that HPV infections play a major role in the development of urothelial bladder cancer.

Non-invasive differentiation of kidney stone types using X-ray dark-field radiography.

Treatment of renal calculi is highly dependent on the chemical composition of the stone in question, which is difficult to determine using standard imaging techniques. The objective of this study is to evaluate the potential of scatter-sensitive X-ray dark-field radiography to differentiate between the most common types of kidney stones in clinical practice. Here, we examine the absorption-to-scattering ratio of 118 extracted kidney stones with a laboratory Talbot-Lau Interferometer. Depending on their chemical composition, microscopic growth structure and morphology the various types of kidney stones show strongly varying, partially opposite contrasts in absorption and dark-field imaging. By assessing the microscopic calculi morphology with high resolution micro-computed tomography measurements, we illustrate the dependence of dark-field signal strength on the respective stone type. Finally, we utilize X-ray dark-field radiography as a non-invasive, highly sensitive (100%) and specific (97%) tool for the differentiation of calcium oxalate, uric acid and mixed types of stones, while additionally improving the detectability of radio-lucent calculi. We prove clinical feasibility of the here proposed method by accurately classifying renal stones, embedded within a fresh pig kidney, using dose-compatible measurements and a quick and simple visual inspection.

Metabolic evaluation and recurrence prevention for urinary stone patients: EAU guidelines.

CONTEXT: An optimum metabolic evaluation strategy for urinary stone patients has not been clearly defined. OBJECTIVE: To evaluate the optimum strategy for metabolic stone evaluation and management to prevent recurrent urinary stones. EVIDENCE ACQUISITION: Several databases were searched to identify studies on the metabolic evaluation and prevention of stone recurrence in urolithiasis patients. Special interest was given to the level of evidence in the existing literature. EVIDENCE SYNTHESIS: Reliable stone analysis and basic metabolic evaluation are highly recommended in all patients after stone passage (grade A). Every patient should be assigned to a low- or high-risk group for stone formation. It is highly recommended that low-risk stone formers follow general fluid and nutritional intake guidelines, as well as lifestyle-related preventative measures to reduce stone recurrences (grade A). High-risk stone formers should undergo specific metabolic evaluation with 24-h urine collection (grade A). More specifically, there is strong evidence to recommend pharmacological treatment of calcium oxalate stones in patients with specific abnormalities in urine composition (grades A and B). Treatment of calcium phosphate stones using thiazides is only highly recommended when hypercalciuria is present (grade A). In the presence of renal tubular acidosis (RTA), potassium citrate and/or thiazide are highly recommended based on the relative urinary risk factor (grade A or B). Recommendations for therapeutic measures for the remaining stone types are based on low evidence (grade C or B following panel consensus). Diagnostic and therapeutic algorithms are presented for all stone types based on the best level of existing evidence. CONCLUSION: Metabolic stone evaluation is highly recommended to prevent stone recurrences. PATIENT SUMMARY: In this report, we looked at how patients with urolithiasis should be evaluated and treated in order to prevent new stone formation. Stone type determination and specific blood and urine analysis are needed to guide patient treatment.

A phase IIA dose-finding study of PVP-hypericin fluorescence cystoscopy for detection of nonmuscle-invasive bladder cancer.

PURPOSE: To determine the optimum dosage and instillation time for water-soluble polyvinylpyrrolidone (PVP)-hypericin for photodynamic diagnosis of bladder cancer and to monitor its use in regard to patient safety. PATIENTS AND METHODS: Forty patients with a cystoscopically suspected bladder neoplasm were enrolled in this prospective phase IIA study. Different combinations of PVP-hypericin dosage (225 µg and 75 µg and instillation time (120, 60, 30, 15 min) were used to evaluate the optimal conditions. After a run-in cohort of five patients to validate the test method, each group comprised seven patients. All intravesical lesions were documented, and their fluorescence characteristics were recorded. Dose finding was the primary, safety the secondary end point. RESULTS: Fluorescence intensities for the first two groups (225 µg PVP-hypericin for 120 and 60 min, respectively) were not different. For group three (225 µg for 30 min), both specific fluorescence and background noise were reduced. A shorter instillation time (225 µg for 15 min) or lower dose (75 µg for 30 min) was considered insufficient for lesion identification. A dose of 225 µg PVP-hypericin instilled for 30 minutes was determined as appropriate for the detection of lesions. Of the total 93 identified lesions, 62 were detected with both white light and fluorescence, 25 were seen with blue light only, and six with white light only. It was possible to identify additionally two carcinoma in situ, eight pTa, and one pT1 lesions with PVP-hypericin and blue light. PVP-hypericin was safe and well tolerated. CONCLUSION: The optimum combination of dosage of PVP-hypericin and its instillation time was established and will be used to determine sensitivity and specificity of PVP-hypericin cystoscopy in a larger multicenter phase IIB study. The preliminary data of this study hint to a higher sensitivity of hypericin-assisted fluorescence cystoscopy.