Comparative analysis of scoring systems for patients undergoing retrograde intrarenal surgery with isolated lower calyx stones.

PURPOSE: It is critical to provide patients with accurate information on potential surgical outcomes during the preoperative phase. Several scoring systems have been developed for this specific purpose. This study aimed to examine the predicted efficacy of scoring systems in patients with isolated lower calyx stones who underwent retrograde intrarenal surgery (RIRS). METHODS: We performed a retrospective analysis of 85 patients who underwent RIRS for lower calyx stones between 2016 and 2023. The study computed each participant's Resorlu-Unsal Stone score (RUSS), R.I.R.S. scoring system score, Modified Seoul National University Renal Stone Complexity (S-ReSC) score, S.T.O.N.E. score, Ito's nomogram, and T.O.HO score. Residual stones less than 4 mm were classified as clinically insignificant residual fragments (CIRFs) and regarded as successful. Following that, we used receiver-operating characteristic (ROC) curves to compare various scoring systems' success predictions. RESULTS: The median scores for RUSS, R.I.R.S. scoring system, Modified S-ReSC, S.T.O.N.E., Ito's nomogram, and T.O.HO score were 1 (1), 7 (2), 2 (0), 11 (1), 18 (4), and 7 (1), respectively. When CIRF cases were included, the stone-free rate increased to 80%. Only Ito's nomogram from scoring systems has a statistically significant cut-off value for success in ROC analysis (p = 0.021). In multivariate analysis, stone volume and preoperative hydronephrosis were associated with success (p = 0.004 and p = 0.035, respectively). CONCLUSION: In the multivariate analysis, none of the scoring systems were significantly associated with success. Hence, a new scoring system must be developed exclusively for patients with isolated lower pole stones undergoing RIRS.

The Impact of Pelvicalyceal System Anatomy on Stone Formation in Patients with Single Lower Pole Calyceal Stone on Computed Tomography Urography.

BACKGROUND: To compare various lower pole pelvicalyceal anatomical factors of stone bearing kidney with contralateral normal kidneys and determine whether these factors predispose to stone formation in one kidney. METHODS: A descriptive study was done with Computed Tomography of 54 patients with solitary lower pole calculus in one kidney and normal contralateral kidney were included. Various lower pole pelvicalyceal anatomical factors like infundibulopelvic angle, infundibular width, infundibular length and calyceopelvic height of both stone bearing and contralateral kidneys were measured and compared for any differences Results: The mean infundibular width was 5.4±1.9mm on stone bearing kidneys and 5.2±2.05mm on contralateral normal kidneys. The mean infundibular length was 18.9±4.4mm on stone bearing kidneys and 18.8±3.9mm on contralateral normal kidneys. The mean infundibulopelvic angle was 47.9±10.8° on stone bearing kidneys and 47.6±11.2° on contralateral kidneys. The mean calyceopelvic height was 15.7±4.6mm on stone bearing kidneys and 15.5±3.9mm (range 7.5to 23.1mm) on contralateral kidneys. There were no statistically significant differences between stone bearing and contralateral normal kidneys in respect to these pelvicalyceal anatomical factors. CONCLUSIONS: In this study, we found no significant difference in lower pole pelvicalyceal anatomical factors between stone bearing kidneys and contralateral normal kidneys and therefore these factors do not seem to have significant role in stone formation in one kidney compared with the other.

Temperature profile during endourological laser activation: introducing the thermal safety distance concept.

PURPOSE: To examine temporal-spatial distribution of heat generated upon laser activation in a bench model of renal calyx. To establish reference values for a safety distance between the laser fiber and healthy tissue during laser lithotripsy. METHODS: We developed an in-vitro experimental setup employing a glass pipette and laser activation under various intra-operative parameters, such as power and presence of irrigation. A thermal camera was used to monitor both temporal and spatial temperature changes during uninterrupted 60-second laser activation. We computed the thermal dose according to Sapareto and Dewey's formula at different distances from the laser fiber tip, in order to determine a safety distance. RESULTS: A positive correlation was observed between average power and the highest recorded temperature (Spearman's coefficient 0.94, p < 0.001). Irrigation was found to reduce the highest recorded temperature, with a maximum average reduction of 9.4 °C at 40 W (p = 0.002). A positive correlation existed between average power and safety distance values (Spearman's coefficient 0.86, p = 0.001). A thermal dose indicative of tissue damage was observed at 20 W without irrigation (safety distance 0.93±0.11 mm). While at 40 W, irrigation led to slight reduction in mean safety distance (4.47±0.85 vs. 5.22±0.09 mm, p = 0.08). CONCLUSIONS: Laser settings with an average power greater than 10 W deliver a thermal dose indicative of tissue damage, which increases with higher average power values. According to safety distance values from this study, a maximum of 10 W should be used in the ureter, and a maximum of 20 W should be used in kidney in presence of irrigation.

Illumination matters part IV: blackout and whiteout in flexible ureteroscopy - first report on a phenomenon observed by PEARLS.

PURPOSE: To date, no study has evaluated effects of varying brightness settings on image quality from flexible ureteroscopes submerged in saline. The aim was to evaluate blackout and whiteout occurrences in an in-vitro kidney calyx model. MATERIAL AND METHODS: We evaluated a series of contemporary flexible ureteroscopes including the Storz Flex-Xc and Flex-X2s, Olympus V3 and P7, Pusen 7.5F and 9.2F, as well as OTU WiScope using a 3D-printed enclosed pink in-vitro kidney calyx model submerged in saline. Endoscopic images were captured with ureteroscope tip placed at 5 mm,10 mm and 20 mm distances. The complete range of brightness settings and video capture modes were evaluated for each scope. Distribution of brightness on a grayscale histogram of images was analyzed (scale range 0 to 255). Blackout and whiteout were defined as median histogram ranges from 0 to 35 and 220 to 255, respectively (monitor image too dark or too bright for the human eye, respectively). RESULTS: Blackout occurred with the P7, Pusen 7.5F, 9.2F and WiScope at all distances, and V3 at 20 mm - with lowest brightness settings. Whiteout occurred with Flex-X2s, V3 and P7 at 5 mm and 10 mm, as well as with V3 and P7 at 20 mm - mostly with highest brightness settings. The Flex-Xc had neither blackout nor whiteout at all settings and distances. CONCLUSION: Blackout or whiteout of images is an undesirable property that was found for several scopes, possibly impacting diagnostic and therapeutic purposes during ureteroscopy. These observations form a guide to impact a urologist's choice of instruments and settings.

Prone vs supine percutaneous nephrolithotomy: does position affect renal pelvic pressures?

The purpose of this study was to measure and compare renal pelvic pressure (RPP) between prone and supine percutaneous nephrolithotomy (PCNL) in a benchtop model. Six identical silicone kidney models were placed into anatomically correct prone or supine torsos constructed from patient CT scans in the corresponding positions. A 30-Fr renal access sheath was placed in either the upper, middle, or lower pole calyx for both prone and supine positions. Two 9-mm BegoStones were placed in the respective calyx and RPPs were measured at baseline, irrigating with a rigid nephroscope, and irrigating with a flexible nephroscope. Five trials were conducted for each access in both prone and supine positions. The average baseline RPP in the prone position was significantly higher than the supine position (9.1 vs 2.7 mmHg; p < 0.001). Similarly, the average RPP in prone was significantly higher than supine when using both the rigid and flexible nephroscopes. When comparing RPPs for upper, middle, and lower pole access sites, there was no significant difference in pressures in either prone or supine positions (p > 0.05 for all). Overall, when combining all pressures at baseline and with irrigation, with all access sites and types of scopes, the mean RPP was significantly higher in the prone position compared to the supine position (14.0 vs 3.2 mmHg; p < 0.001). RPPs were significantly higher in the prone position compared to the supine position in all conditions tested. These differences in RPPs between prone and supine PCNL could in part explain the different clinical outcomes, including postoperative fever and stone-free rates.

[The 1-cm lower calyx calculus: SWT, URS or Mini-PCNL? Guidelines vs. reality.] / Der 1 cm UKG-Stein: ESWL, URS oder Mini-PCNL? Leitlinien versus Realität.

Urinary stones of the upper urinary tract can be considered a widespread public health concern due to their high incidence and prevalence and their health policy-related and financial implications. A significant proportion of newly diagnosed kidney stones are lower-pole stones, i.e., stones affecting the lower calyx group of the renal pelvicalyceal system. These are often diagnosed by chance, i.e., as incidental findings during ultrasound or CT scans performed for other reasons, or as "secondary stones" detected during the diagnostic work-up of symptomatic urinary stones in other locations. Residual disintegrates after extracorporeal shock-wave lithotripsy (ESWL) or endoscopic stone therapy constitute a further, quantitatively significant group. These incidentally discovered lower-pole stones are often characterised by their small size and lack of symptoms. It stands to reason that some of these small, asymptomatic lower-pole stones do not always remain small and asymptomatic, and that treatment tends to become more complex with increasing size. There has been an astonishing lack of published studies with a high level of evidence over the last 20 years to provide a conclusive and reproducible answer to the question posed in this review. Small, asymptomatic stones can be monitored. Symptomatic and rapidly growing stones should be treated. There is a lack of valid risk factors allowing an identification of subgroups that should be treated prophylactically at the asymptomatic stage. In active therapy, a 10-to-20-year-old principle still holds true today: a high stone-free rate in one therapy session is offset by an increased complication rate, with increasing miniaturisation in endourology (retrograde and percutaneous) and increasingly effective laser disintegration shifting this basic principle more and more in favour of flexible URS and (mini, micro) PCNL. The range of indications for ESWL is undoubtedly becoming smaller, and this also applies to lower-pole stones. The results of an ongoing prospective randomised study comparing the different treatment modalities, albeit with recruitment difficulties, are still pending.

What should the optimal access site be for percutaneous treatment of anterior lower pole calyx stones?

OBJECTIVES: Compared to other stone groups, anterior calyx stones are more challenging for endourologists to treat. This study aims to evaluate the differences between our latest technique and conventional techniques for treating anterior calyx stones in the lower pole. MATERIALS AND METHODS: Patients with isolated anterior lower pole calyx or complex lower pole stones with anterior calyx branching were included in the study. The first group included lower pole access, while the second group included percutaneous treatment through the middle or upper pole. In the first group, the posterior calyx or direct anterior calyx approach was utilised depending on whether the stone was isolated calyx, complex structure or calyx anatomy, while in the second group, percutaneous nephrolithotomy was performed through the middle or upper pole posterior calyx access. RESULTS: There were 37 patients in Group 1 and 25 patients in Group 2. Both groups were similar regarding patient age, sex, stone burden, and stone localisation (p > 0.05). When comparing operative and post-operative data between groups, it was found that the stone clearance rate, number of accesses, and haematocrit decrease were statistically superior in the second group (p: 0.003, p: 0.002, p: 0.018), with no significant difference in mean operative time, length of hospital stay, fluoroscopy time and pain score (p > 0.05). CONCLUSIONS: Percutaneous surgery utilising an access from a calyx distal to the stone may offer better clearance and lower morbidity rates for lower pole stones involving the anterior calyx.

Kidney collecting system anatomy applied to endourology - a narrative review.

OBJECTIVE: To evaluate the surgical anatomy of the kidney collecting system through a narrative review of the literature, highlighting its importance during diagnosis and its approach during surgical procedures for the treatment of renal stones. MATERIAL AND METHODS: We carried out a review about the anatomy of the kidney collecting system. We analyzed papers published in the past 40 years in the databases Pubmed, Embase and Scielo, and we included only papers in English and excluded case reports, editorials and opinions of specialists. RESULTS: Renal collecting system could be divided in four groups: A1 - kidney midzone (KM), drained by minor calyx that are dependent on the superior or the inferior caliceal groups; A2 - KM drained by crossed calyx, one draining into the superior caliceal group and another draining into the inferior caliceal group; B1 - KM drained by a major caliceal group independent of both the superior and inferior groups; and B2 - KM drained by minor calyx entering directly into the renal pelvis. Some details and anatomic variations of the collecting system are related to clinical and radiological aspects, particularly perpendicular calyces, interpyelocalyx space, position of calyces in relation to renal border, classification of the renal collecting system, infundibular diameter and the angle between the lower infundibulum and renal pelvis. CONCLUSION: The knowledge of intra-renal collecting system divisions and variations as the angle between the renal pelvis and lower infundibula, position of the calices in relationship with renal edge and the diameter and position of the calyces are important for the planning of minimally invasive renal surgeries.

Navigating Entire Collecting System During Supine Percutaneous Nephrolithotomy: Is Rigid Nephroscopy Enough? A Prospective Study by International Alliance of Urolithiasis Supine Percutaneous Nephrolithotomy Working Group.

Background: During percutaneous nephrolithotomy (PCNL), accessibility to the entire collecting system is crucial to check the presence of any residual stone fragments. In this study, we aimed to identify the rate of accessibility of all caliceal cavities using lower-, middle- and, upper-pole punctures and the eventual benefit of simultaneous utilization of retrograde/antegrade flexible nephroscopy. Materials and Methods: Data of patients undergone supine PCNL in five different institutions were collected prospectively. Access status to other poles of the kidney with a rigid nephroscope, antegrade access status to the other poles of the kidney with a flexible nephroscope, or retrograde access with a flexible ureterorenoscope were all evaluated together with detection of residual fragments. Access status to the other poles of the kidney with anterograde and retrograde approaches were compared. Results: Data of 226 patients were analyzed and stone-free status was achieved in 207 (91.6%) of the patients. The entire collecting system could be successfully approached by a rigid nephroscope in 50% of the cases through middle-pole puncture. This rate was significantly higher than that of lower-pole puncture (37.1%) and upper-pole puncture (28.1%) (P = .035). The successful approach to the entire collecting system with retrograde ureterorenoscopy was possible in 97.6% of the cases, while the successful approach was possible in 48 of the 60 cases (80%) with the retrograde approach (P < .0001). Conclusions: During PCNL, evaluation of the entire collecting system with rigid nephroscopy is not possible in a significant portion of the patients. We believe that the application of flexible nephroscopy, particularly via retrograde approach improves the stone-free rates.

Ureterocalicostomy for complex upper ureteral stricture: a narrative review of the current literature.

Upper ureteral stricture is a relatively rare but increasingly encountered condition in clinical practice. While simple stricture can often be addressed through endoluminal treatment or surgical reconstruction, complex upper ureteral stricture poses challenges, particularly in patients with ureteropelvic junction obstruction (UPJO) or perirenal pelvic fibrosis and scarring resulting from previous surgeries. These cases present difficulties for traditional endoluminal and ureteral reconstruction treatments, posing a significant problem for many clinical surgeons. Our study involved a thorough search and comprehensive analysis of the existing literature on Ureterocalicostomy (UC). The literature indicates that UC is a safe and effective treatment for ureteral stenosis. By resecting the renal lower pole parenchyma, it is possible to achieve mucosal anastomosis between the calyceal and ureteral mucosa, leading to the restoration of normal urinary excretion. This technique has emerged as an alternative for treating complex upper ureteral strictures. However, there is a lack of direct comparative studies between open surgery and minimally invasive surgery. Our findings revealed a scarcity of relevant review documents, with most being case reports or retrospective studies conducted in single centers with small sample sizes. Therefore, it is crucial to conduct large-scale, multicenter prospective studies and long-term follow-up to validate the long-term efficacy of UC. This article reviews the development history of UC and focuses on a comprehensive discussion of its indications, surgical techniques, and complications.

Comparison of retrograde intrarenal surgery and percutaneous nephrolithotomy in multiple calyceal stones: a match pair analysis of 190 cases / Comparación entre cirugía retrograda intrarenal (CRIR) y nefrolitotomía percutánea (NLP) en litiasis caliciales múltiples: análisis pareado de 190 casos

OBJECTIVES: The current nephrolithiasis guidelines have no recommendation about multiple calyceal stones treatment. We aimed to compare the results of two effective methods of RIRS and PNL operations in the treatment of multicalyx stones. METHODS: Data of patients who underwent RIRS or PNL for multicalyx stones between September 2014 and May 2019 in our clinic were evaluated retrospectively. In both groups, stone-free and complication rates, hospital stay, scopy times, and operation times were examined. In RIRS group, the number of sessions and total stone-free rates at the end of each session were evaluated separately. RESULTS: A total of 162 patients in the RIRS group, and 103 patients in the PNL group were evaluated. After the match pair 1:1, data of 95 patients were selected in each group. Stone burden, number, density, ASA scores, BMI were similar in both groups. At the end of the first session RIRS, 59 (62.1%) patients became stonefree, while in the PNL group 73 (76.8%) patients (p: 0.027). The statistical analysis showed that the stonefree rates obtained in the second sessions in the RIRS group were similar to those of the PNL group. After a total of 124 sessions of RIRS, a stone-free rate of 81.1% was achieved by 1.3 sessions on average. CONCLUSION: At least two session of RIRS is as effective as PNL on multiple calyceal stones. Stage RIRS can be an alternative to PNL at multicalyceal renal stones

OBJETIVOS: Las guías actuales de nefrolitiasis no tienen recomendaciones sobre el tratamiento de litiasis caliciares múltiples. Nuestro objetivo es comparar los resultados de 2 métodos de tratamiento efectivos de CRIR y NLP en el tratamiento de litiasis mul-ticaliciares. MÉTODOS: Los datos de pacientes que recibieron CRIR y NLP para el tratamiento de litiasis múltiples caliciares entre septiembre 2014 y mayo 2019 en nuestra clínica, fueron evaluados retrospectivamente. En ambos grupos, la tasa libre de litiasis y las complicaciones, la estancia hospitalaria, el tiempo de escopia, y el tiempo quirúrgico fueron examinados. En el grupo CRIR, el número de sesiones y la tasa libre de litiasis al final de cada sesión fueron evaluadas de forma independiente. RESULTADOS: Un total de 162 pacientes en el grupo CRIR y 103 en el grupo NLP fueron evaluados. Después del emparejamiento de pacientes 1:1, los datos de 95 pacientes fueron seleccionados en cada grupo. El volumen litiásico, número, densidad, ASA, IMC fueron similares entre grupos. Al final de la primera sesión de CRIR, 59 (62%) pacientes llegaron a ser libres de litiasis, mientras que en grupo de NLP fueron 73 (76/8%) (p = 0,027). El análisis estadístico demostró que las tasas libres de litiasis obtenidas en la segunda sesión de CRIR fueron similares a las de NLP. Después de un total de 124 sesiones de CRIR, la tasa libre de litiasis fue de 81,8% en una media de 1,3 sesiones. CONCLUSIONES: Como mínimo dos sesiones de CRIR es tan efectivo como una NLP en litiasis calicares múltiples. CRIR en múltiples sesiones puede ser una alternativa a la NLP para litiasis caliciares múltiples

Tratamiento laparoscópico de la litiasis en el riñón en herradura / Laparoscopic management of horseshoe kidney stones

OBJETIVO: El riñón en herradura constituye la anomalía de la fusión más frecuente. Sus características anatómicas incrementan la formación de litiasis y dificultan su resolución. MATERIAL Y MÉTODOS: Presentamos dos varones con riñones en herradura diagnosticados mediante TC abdominal en un caso de litiasis piélica de 5 cm y en el otro de una litiasis en pelvis renal con otras caliciales más pequeñas. Realizamos una pielolitectomía laparoscópica extrayendo las litiasis piélicas, introducimos un cistoscopio flexible por un trocar para extraer las litiasis caliciales. RESULTADOS: El postoperatorio cursó sin incidencias y retiramos el catéter doble jota 3 semanas después sin evidenciar fuga urinaria ni litiasis residual, encontrándose los pacientes 6 meses después sin litiasis. CONCLUSIONES: El abordaje laparoscópico de la litiasis constituye una alternativa en los casos complejos como en el riñón en herradura. Utilizar un cistoscopio flexible permite navegar en las cavidades renales aumentando la eficacia del abordaje

OBJECTIVE: : Horseshoe kidney is the most common renal fusion anomaly. Its peculiar anatomical characteristics increase the risk of lithiasis formation and always entails a surgical challenge for its treatment. MATERIAL AND METHODS: We present the cases of men with horseshoe kidneys diagnosed by CT one case of a large pyelic lithiasis with others of a smaller size in the calyces, and the other of a big solitary lithiasis in renal pelvis. RESULTS: We performed a laparoscopic pyelolitectomy to remove the pyelic lithiasis and we used a flexible cystoscope through a trocar to extract the calyceal stones. The postoperative period was uneventful without evidence of urinary leakage or residual lithiasis. CONCLUSIONS: The laparoscopic approach to lithiasis is a suitable alternative in especially complex cases such as horseshoe kidney. The use of a flexible cystoscope allows to navigate through the renal cavities and extract the lithiasis which cannot be accessed through laparoscopic instruments, improving the efficiency of this approach

Resultados de varias técnicas mínimamente invasivas en litiasis del polo inferior de 1-2 centímetros: estudio prospectivo, randomizado / Outcomes of different minimally invasive techniques in lower calyceal stones of 1 to 2 centimeters: A prospective, randomized study

OBJETIVO: Comparar la eficiencia, seguridad y coste de la ureteroscopia flexible polo inferior y la nefrolitotomia percutanea para el tratamiento de litiasis del polo inferior de 1 a 2 cm de diámetro. MÉTODOS: Esto fue un estudio prospectivo randomizado. En total, 175 pacientes fueron randomizados en 5 grupos (35 en cada grupo): Grupo A se manejó con uretereroscopia flexible retrograda polo inferior (UFRI), Grupo B con micronefrolitotomia percutánea (NLP); grupo C con ultra-mini NLP; Grupo D con mini NLP y el grupo E con estándar NLP. Tiempo quirúrgico y de fluoroscopio, estancia hospitalaria, tasa libre de litiasis (TLL), complicaciones, ureterolitotripsias secundarias y coste fueron comparados entre grupos. RESULTADOS: Un total de 168 pacientes fueron incluidos en el análisis final. La TLL fue de 76%, 77%, 90,1%, 94,1% y 94%. La estancia media hospitalaria fue de 1, 1,5, 2,2, y 3 días para UFRI, micoNLP, ultra-mini NLP, mini NLP y estándar NLP (p < 0,001) .El coste total medio de los procedimientos fue de 1250 USD, 962 USD, 695 USD, 632 USD y 619 USD respectivamente. El tiempo medio de retorno a las actividades diarias fue de 3,9, 4,5, 6,5, 9,3 y 13,5 días para UFRI, micro NLP, ultra-mini NLP, mini NLP,estándar NLP, respectivamente (p < 0,001). CONCLUSIONES: TLL para el tratamiento de litiasis de polo inferior fue mayor para ultra-mini NLP, mini NLP y estándar NLP que para micro NLP y UFRI. Ademas, los pacientes deben ser informados sobre los resultadoscon los otros procedimientos; con aumento de la agresividad del tratamiento, el coste del procedimiento disminuye, pero la estancia hospitalaria y el retorno a las actividades diarias se incrementa

OBJECTIVE: To compare efficiency, safety and full cost of lower retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL) types for the treatment of lower calyceal stones between 1 and 2 cm in size. METHODS: This was a prospective, randomized study. In all, 175 patients were randomly divided into five groups of 35 patients each: Group A was managed by RIRS, Group B by micro PNL, Group C by ultra-mini PNL, Group D by mini PNL, and Group E by standard PNL. Operating and fluoroscopy time, length of hospital stay, stone-free rates (SFR), complications, secondary ureterolithotripsy and cost were compared between groups. RESULTS: A total of 168 patients were included in the final analysis. The SFR was 76%, 77%, 90.1%, 94.1% and 94%; median length of hospital stay 1, 1.5, 2, 2, and 3 days was for RIRS, micro, ultra-mini, mini, and standard PNL, respectively (p < 0.001). The mean total costs of the procedures per case were $1,250, $962, $695, $632, and $619, and the mean return to daily activities time was 3.9, 4.5, 6.5, 9.3, and 13.5 days for RIRS, micro, ultra-mini, mini, and standard PNL, respectively (p < 0.001). CONCLUSIONS: SFR of treatment of lower calyceal stone was higher in ultra-mini, mini and standard PNL than micro PNL and RIRS. Moreover, patients should be informed about the results of all different procedures; with increasing of the invasiveness of treatment, cost of the procedure decrease; but the hospital stay and return to daily activity interval increase

Manejo de la litiasis asociada a estenosis intrarrenales mediante el uso del videoureterorrenoscopio flexible / Management of lithiasis associated with intrarrenal stenosis using the flexible videoureteroroscope

OBJETIVO: Reportar dos casos de estenosis intrarrenales asociado a litiasis manejados con el videoureterrenoscopio flexible (STORZ) y el láser de Holmium (CALCULASE II) como herramienta tecnológica y moderna. MATERIAL Y MÉTODOS: El caso 1 presentaba un divertículo calicial el cual fue tratado mediante la incisión del ostium diverticular con láser y posterior tratamiento de la litiasis. El segundo caso presentaba una estenosis del ostium caliceal secundario a una cirugía percutánea previa pudiendo acceder al cáliz mediante la dilatación del mismo. RESULTADOS: El tiempo quirúrgico fue de 60 y 82 minutos para el caso 1 y 2, con una estancia hospitalaria de 8 horas y sin complicaciones perioperatorias. La tasa libre de enfermedad fue del 100%. CONCLUSIONES: El videoureterorrenoscopio flexible y laser de Holmium para el manejo de las estenosis intrarrenales es altamente efectivo y seguro con las ventajas de presentar menos complicaciones perioperatorias, menos invasividad y ser ambulatorio comparado con la cirugía percutánea

OBJECTIVE: Intrarenal stenosis, even caliceal diverticula or neck diverticular stenosis, associated with lithiasis are infrequent therefore their management is a challenge. The aim of this article is to report two cases who underwent retrograde intrarenal surgery and Holmium laser as a modern technological tool, proposing a new gold standard. METHODS: We report 2 cases of intrarenal stenosis associated with lithiasis managed with flexible videoureteroscope (STORZ) and Holmium laser (CALCULASE II). One case presented a caliceal diverticulum and the other a caliceal ostium stenosis secondary to previous percutaneous surgery. The ostium was incised with laser to Access the diverticulum in the first case and in the second case a dilatation was required. Lithiasis treatment was performed with laser. Disease free rate was defined when the cavity completely disappeared and lithiasis fragments were les than 2 mm on CT Scan one month after procedure. RESULTS: Surgical time were 60 and 82 minutes for cases 1 and 2, respectively. Both patients evolved satisfactorily with 8 hours hospital stay and without perioperative complications. The disease-free rate was 100%. CONCLUSION: Flexible videoureterorrenoscopy and Holmium laser for the management of intrarenal stenosis are highly effective and safe with the advantages of les perioperative complications, less invasiveness and being an outpatient procedure compared to percutaneous surgery

Retrograde vs. antegrade flexible nephroscopy for detection of residual fragments following PNL: a prospective study with computerized tomography control

ABSTRACT Introduction: The main aim of stone surgery is to establish stone free status. Performing flexible nephroscopy is an effective tool in this manner. The aim of this study was to evaluate the role of retrograde flexible nephroscopy for detection of residual fragments following percutaneous nephrolithotomy (PNL) in comparison with antegrade approach. Materials and Methods: Data of 137 patients underwent ECIRS was collected prospectively. In all cases following stone clearance, collecting system was checked for residual fragments. First antegrade than retrograde flexible nephroscopy was performed and success rates to reach all calices and detection of residual fragments were noted. All patients underwent CT and success rate of antegrade and retrograde approaches were compared. PPV and NPV of retrograde approach to detect residual fragments were calculated. Results: Antegrade and retrograde nephroscopy successfully accessed all of the calices in 101 (73.7%) and 130 (94.9%) patients respectively (p<0.0001). Residual fragments were observed in 18 (13.1%) patients following antegrade flexible nephroscopy. Retrograde approach identified residual stones in 17 more cases. These cases were treated with flexible nephroscopy or secondary percutaneous tract. Postoperative CT revealed residual stones in 10 (7.3%) patients. PPV and NPV of retrograde flexible nephroscopy were 83.3% and 96.2%. Conclusions: Flexible nephroscopy effectively detects residual fragments following PNL. Retrograde approach was more successful than antegrade approach to reach all calices. We recommend performing retrograde flexible nephroscopy following PNL especially in complex cases as it has the potential to increase SFR, decrease the need for second look surgery and unnecessary postoperative imaging.

Divertículo calicial y su diagnóstico incidental / Calyceal diverticulum and its incidental diagnosis

Introducción: El divérticulo calicial se detecta en 0,21 a 0.60 por ciento de los urogramas excretores. Objetivos: Describir una paciente con diagnóstico incidental de esta anomalía y su seguimiento durante 11 años. Presentación del caso: Durante la realización de un urograma excretor para el estudio de una hidronefrosis en una niña de siete años de edad, se detectó un divertículo calicial en el riñón contralateral y después de 11 años de seguimiento ultrasonográfico no se ha demostrado modificación ni complicación del divertículo. Conclusiones: El divertículo calicial es una anomalía congénita que puede mantenerse sin complicaciones durante años por lo que debe tratarse conservadoramente(AU)

ABSTRACT Introduction: Calyceal diverticulum is detected in 0,21 percent to 0.60 percent of excretory urogram. Objectives: To describe a patient with an incidental diagnosis of this anomaly and her follow up during 11 years. Case presentation: During the performance of an excretory urogram for studying a hydronefrosis in a seven years old girl, a calyceal diverticulum was detected in the contralateral kidney; and after 11 years of ultrasonographic follow-up there has been no modifications or complication related with the diverticulum. Conclusions: Calycial diverticulum is a congenital anomaly that can last years without presenting complications. That is why it must be treated conservatively(AU)

Divertículos caliciales en niños: hallazgos radiológicos y formas de presentación / Calyceal diverticula in children: imaging findings and presentations

El divertículo calicial (DC) es una eventración quística intraparenquimatosa tapizada por epitelio celular transitorio con una estrecha conexión infundibular con los cálices o pelvis del sistema colector renal, por lo que el término más exacto es divertículo pielocalicial. Muy raro en la edad pediátrica, puede ser sintomático y requerir tratamiento. Está infradiagnosticado por confundirse con quistes renales simples por ecografía; su diagnóstico se confirma con tomografía computarizada (TC) o resonancia magnética (RM) en fase excretora, para determinar su seguimiento y manejo. Nuestro objetivo es mostrar las diferentes formas de presentación de los DC en la edad pediátrica, haciendo hincapié en los criterios ecográficos que permiten una aproximación diagnóstica y en los hallazgos definitivos en TC y RM. También discutimos el diagnóstico diferencial con otras lesiones quísticas renales y su tratamiento

A calyceal diverticulum consists of a cystic eventration in the renal parenchyma that is lined with transitional cell epithelium with a narrow infundibular connection with the calyces or pelvis of the renal collector system; thus, the term pyelocalyceal diverticulum would be more accurate. Very rare in pediatric patients, calyceal diverticula can be symptomatic and require treatment. Calyceal diverticula are underdiagnosed because they can be mistaken for simple renal cysts on ultrasonography. To determine the approach to their follow-up and management, the diagnosis must be confirmed by excretory-phase computed tomography (CT) or magnetic resonance imaging (MRI). This article aims to show the different ways that calyceal diverticula can present in pediatric patients; it emphasizes the ultrasonographic findings that enable the lesion to be suspected and the definitive findings that confirm the diagnosis on CT and MRI. It also discusses the differential diagnosis with other cystic kidney lesions and their treatment

Skin to calyx distance is not a predictive factor for miniaturized percutaneous nephrolithotomy outcomes

ABSTRACT Objective To evaluate the predictive value of the distance from skin to calyx (SCD) on the outcome and complication rates of patients undergoing mPNL. Materials and Methods Patient's charts, who had undergone mPNL between June 2012 and June 2015, were analyzed retrospectively. Patients who had a preoperative computerized tomography (CT) were enrolled into the study. Two separateurologists evaluated the CT scans and calculated the SCD defined as the distance between the skin and surface/lateral edge of the calyx, which was the preferred site of entry for percutaneous access. The average value of the two measurements was included inthe final analysis to avoid bias. The mean SCD was 75mm. According to the median SCD value, patients were divided into two groups: group 1 (SCD ≤75) and group 2 (SCD >75). Results A total of 140 patients and 130 patients were enrolled in groups 1 and 2, respectively. The mean operation time and the mean fluoroscopy time was significantly longer in group 2 (p:0.004 vs. p:0.021). The rate of blood transfusion was significantly higher in group 1 (6 patients). None of patientsin group 2required blood transfusion (p:0.017). Stone-free status after a single session of mPNL was 67.1% in group 1 and 75.4% in group 2 (p:0.112). After additional procedures, stone-free rates increased to 84.3% and 85.4% in group 1 and group 2, respectively (p:0.802). Conclusion Our study demonstrated that longer SCD was not a predictive factor for stone-free rates after mPNL. However, SCD over 75mm was associated with longer operation time and fluoroscopy time with lower rates of transfusion.

Crisis de Dietl secundarias a estenosis pieloureteral intermitente en hemiriñón inferior derecho / Dietl crisis secondary to intermittent pyeloureteral stenosis in lower right half of kidney

El dolor abdominal de repetición puede estar originado como consecuencia de episodios intermitentes de distensión de la pelvis renal, conocidas como crisis de Dietl. Varón, de 7 años, con crisis de dolor abdominal y vómitos de unos 6 meses de evolución. En una ecografía abdominal se observa el riñón derecho, con un sistema doble y una pelvis inferior con diámetro anteroposterior de 8 mm. A pesar de diferentes pruebas de imágenes y analítica, no existe un diagnóstico de certeza por lo que se solicita una ecografía preingesta de líquidos: pelvis de hemisistema inferior derecho de 11 mm de diámetro anteroposterior, seguida de ecografía post-ingesta de líquidos: pelvis de hemisistema inferior de 26 mm. Con el diagnóstico clínico de crisis de Dietl, se realiza lumbotomía, comprobando una dilatación de pelvis inferior, secundaria & compresión extrínseca venosa. Debido a que los síntomas, exploración y exámenes complementarios suelen ser inespecíficos, el diagnóstico de estenosis pieloureteral intermitente se suele retrasar. Una ecografía basal y otra, post-ingesta de líquidos, fueron demostrativas del aumento significativo de diámetro de la pelvis renal inferior derecha (AU)

Repetitive abdominal pain may be a consequence of intermittent episodes of renal pelvis distension, known as Dielt´s crisis. Male, 7 years old, With acute abdominal pain and vomits over a period of 6 months. On abdominal ultrasound, the right kidney is observed having a duplex collecting system and the inferior pelvis measures 8 mm anteroposteriorly. Despite different imaging & analytic tests, there is no certain diagnosis and a pre-fluid intake ultrasound is requested: the right inferior pelvis measures 11 mm anteroposteriorly. On post-fluid intake ultrasound, the right inferior pelvis measures 26 mm. With the clinical diagnosis of Dielt's crisis, a lombotomy is performed, verifying an inferior pelvic dilatation secondary to extrinsic venous compression. Since the symptoms, examination, and additional tests are often nonspecilic, the diagnosis of intermittent pyeloureteral junction stenosis is many times delayed. A baseline ultrasound, together with a second one performed after fluid ingestion, were demonstrative of the signiñcant increase in the diameter of the right inferior renal pelvis (AU)