Infundibulopelvic Angle Research Articles

Pelvicalyceal anatomy and stone related factors as predictors of stone free rate in retrograde intrarenal surgery for lower calyceal stone.

The objective of the present study is to evaluate the various pelvi-calyceal anatomy related and stone related parameters and their influence on stone free rate in retrograde intrarenal surgery for lower calyceal stones. The retrospective analysis of records of 206 patients who underwent retrograde intrarenal surgery for lower calyceal stones from December 2021 and November 2023.The patients were divided into two groups: stone free group and residual stone group. Various factors like patients' characteristics, stone size, volume, numbers, density, infundibular width, infundibulopelvic angle, operative time, lasing time, type of laser, and retreatment rate were compared between two groups. The mean stone size in stone free group was 1.1 ± 0.7 cm whereas in residual stones group was 1.7 ± 0.4 cm (p = 0.03). Overall stone free rate was 62.1% (128/206) whereas residual stone rate was 37.9% (78/206). In stone-free group only 2.3% (3/128) of the patients had an acute infundibulopelvic angle ⩽ 30° whereas in the residual stones group an acute infundibulopelvic angle ⩽ 30° was found in 58.9% (46/78) of the patients (p < 0.001). Patients with an infundibulopelvic angle ⩽ 30°, 93.8% (46/49) had residual stones, whereas infundibulopelvic angle > 30° only 20.1% (32/157) had residual stones (p < 0.001). Multivariate logistic regression analysis has demonstrated that Infundibulopelvic angle and stone size were the only significant factors in predicting stone free rate for lower calyceal stone. Infundibulopelvic angle and stone size have significant impact on the stone free rates in retrograde intrarenal surgery for lower calyceal stones.

Effect of infundibulopelvic angle on outcomes of ureteroscopy: a systematic review and meta-analysis

PurposeThe infundibulo-pelvic angle (IPA) is reportedly a predictor of successful ureteroscopy for lower pole renal stones, however there is uncertainty at which IPA success is likely. We therefore aimed to perform a meta-analysis and determine at which the angle of likely success and failure.MethodsWe performed a systematic review and meta-analysis as per Cochrane guidelines in accordance to the PRISMA statement. The review was registered with PROSPERO prior to commencement (ID: CRD42022296732). We included studies reporting on outcomes of ureteroscopy for lower pole stones, with IPA. We excluded patients undergoing alternative treatments for lower pole stones, anatomical abnormalities and studies with < 10 patients. We assessed bias with the Newcastle-Ottawa scale. We performed meta-analysis in R, and summarised the findings as per GRADE.ResultsOverall, there were 13 studies included, with 10 included for meta-analysis. These studies covered n = 1964 patients (71% stone free). Overall, the stone free patients had a significantly less acute mean IPA (52o ± 9o), compared to the non-stone free patients (39o ± 7o), on meta-analysis (REM MD = -13.0, 95% CI: -18.7 to -7.2, p < 0.001). On examination of forest plots, at IPA < 30o no patients were stone free, whilst > 50o all were stone free. Risk of bias was moderate, and certainty of evidence was ‘very low’.ConclusionWith a very low certainty of evidence, we demonstrate that at an IPA of < 30o no patient is stone free, whilst > 50o all patients (in this review) are stone free. More evidence is therefore needed.

Assessment of Factors Responsible for Stone-Free Status After Retrograde Intrarenal Surgery.

Aim The study aimed to evaluate the predictive factors that determined stone-free rate (SFR) after retrograde intrarenal surgery (RIRS). Materials and methods This prospective study was conducted on 183 patients undergoing RIRS for renal stones. Patients were categorized into two groups, depending on stone-free status one month following the procedure. SFRwas defined as the complete absence of stones or stones <4 mm. The parameters studied included patient demographics, presence of hydronephrosis, presence of preoperative double J-stent, abnormal renal anatomy, and stone characteristics (stone burden, stone number, stone density, stone location, lower pole infundibulopelvic angle, and lower pole renal infundibular length (RIL)). Univariate and multivariate analyses were performed to identify risk factors for residual stones. We assessed the predictive ability of the RIRS score and Resorlu-Unsal stone score (RUSS) for evaluating SFR utilizing receiver operating characteristic (ROC) analysis. Results 183 patients were included inthe study with a median age of 51 years. 131 (71.6%) patients were declared stone-free after the procedure. The mean stone size and density were 16.9 SD±7.5 mm and 1038 SD±342 Hounsfield units (HU) respectively. Stone-free patients had lower stone size (14.3 mm vs. 23.6 mm, p<0.01) and stone density (970 HU vs. 1211 HU, p<0.01) compared to non-stone-free patients. Patients with residual stones had steeper lower pole renal infundibulopelvic angle (RIPA) (31.3° vs. 40.7°, p<0.01) and longer RIL(26.6 mm vs. 21.1 mm, p<0.01). Stone multiplicity (p<0.01), lower pole stone location (p<0.01), and renal malformations (p<0.01)were significant influencing factors for residual renal stones after RIRS. Multivariate analysis revealed stone size, stone density (HU), and stone location as independent predictors for SFR after RIRS. Among the scoring systems, the RIRS score had the highest diagnostic accuracy for SFR (area under the curve (AUC): -0.882, 95% CI-0.828-0.936). Conclusion Stone size, stone density (HU), and stone number are important predictors of SFR after RIRS. Lower pole stone location and abnormal renal anatomy play a substantial role in determining SFR after RIRS. In lower pole stones, a long RIL and acute RIPA negatively influence SFR. Additionally, the RIRS score was found to be a better predictor for SFR than the RUSS score.

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

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. 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. 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.

Evaluate the results of treatment of lower calyces stones by flexible ureteroscopy

Objective: To evaluate the results of the treatment of the lower calyces stones by flexible ureteroscopy and investigate some factors that affect the results of the treatment of the lower calyces stones through flexible ureteroscopy. Materials and methods: A prospective cohort study was performed in 30 patients with 31 kidney stones having lower calyces that were treated with flexible ureteroscopes at Hue Central Hospital from 3/2023 to 3/2024. Results: The average age of the patients was 52.77 ± 14.24 years. The average stone size in computed tomography images is 12.83 ± 3.93 mm. Regarding the number of stones, cases with only one kidney stone account for 51.60%. As for the inferior pelvic angle, 74.20% of the cases had an angle ≥ 45°, while 25.80% had an angle &lt; 45°. The stone-free rate reached 76.70% with stones ≤ 20 mm. Conclusions: the treatment of lower calyx stones by flexible ureteroscopy demonstrated a stone -free rate of 76.70% after 1 month for stones ≤ 20 mm. Factors such as stone size, number of stones and lower pole infundibulopelvic angle all affect the treatment results of flexible endoscopy. Key words: lower calyces, lower pole infundibulopelvic angle, flexible ureterosopy.

New infundibulopelvic angle measurement method can predict stone-free rates following retrograde intrarenal surgery.

To enhance the accuracy of predicting stone-free rates after retrograde intrarenal surgery, we devised a novel approach to assess the renal infundibulopelvic angle. We conducted a retrospective review of patient records for those who underwent retrograde intrarenal surgery for renal stones between April 2018 and August 2019. Patient demographics, stone characteristics, and perioperative data were recorded. Subsequently, we introduced a modified angle measurement called the pelvic stone angle and evaluated its predictive performance for stone-free rates by comparing it with the traditional method in scoring systems. A total of 43 individuals were included in this study. Notable differences in stone burden and Hounsfield unit measurements were found between stone-free and non-stone-free patients. The pelvic stone angle demonstrated a good model fit when used in scoring systems, performing equally well as the conventional approach. The area under the receiver operating characteristic curve for the R.I.R.S. scoring system using the pelvic stone angle and the conventional approach did not show a significant difference. In conclusion, the predictive ability of the pelvic stone angle for stone-free rates was comparable to the old measurement method. Moreover, scoring systems using the pelvic stone angle exhibited a better model fit than those using the conventional approach.

Optimizing outcome reporting after robotic flexible ureteroscopy for management of renal calculi: Introducing the concept of tetrafecta

Robotic flexible ureteroscopy (RFURS) has shown encouraging results in terms of stone free rate (SFR) and better ergonomics compared to conventional FURS. However, few studies have reported its outcomes. The goal of this study was to report our initial results of RFURS, furthermore we proposed a novel metrics for composite outcome reporting named tetrafecta. A retrospective analysis of electronic records of 100 patients treated with RFURS for renal stones between 2019 till 2023 was performed. Tetrafecta criteria included, complete stone removal after a single treatment session, without auxiliary procedures, absence of high-grade complications (GIII-V) and same-day hospital discharge. Mean patient age and stone size were 40.7 ± 9.2 and 11.7 ± 5.8 mm, respectively. Median stone volume was 916 (421–12,235) mm3. Twenty-eight patients had multiple renal stones. Staghorn stones were seen in 12 patients. Preoperative DJ stent was fixed in 58 patients. Median operative time and stone treatment time were 116 min (97–148) and 37 (22–69) min. The median stone treatment efficiency (STE) was 21.6 (8.9–41.6). A strong positive correlation between stone volume and STE (R = 0.8, p < 0.0001). Overall, 73 patients were stone free after the initial treatment session while tetrafecta was achieved in 70 patients. Univariate analysis showed that the stone size (p = 0.008), acute infundibulopelvic angle (p = 0.023) and preoperative stenting (p = 0.017) had significant influence on achieving tetrafecta. Multivariate analysis identified preoperative stenting (OR 0.3, 95% CI 0.1–0.8, p = 0.019) as the only independent predictor of tetrafecta achievement. A comprehensive reporting methodology for reporting outcomes of RFURS is indicated for patient counseling and comparing different techniques. Tetrafecta was achieved in 70% of cases. Presence of significant residual stones ≥ 3mm was the leading cause of missing tetrafecta. Absence of preoperative stent was the only predictor of missing tetrafecta.

A Novel Technique for Relocating Renal Lower Calyceal Stones During Retrograde Intrarenal Surgery: ‘’Jab and Pull’’

Objective : It is advised to move the stones from the lower calyx to the middle or upper calyx using a nitinol basket. In order to protect the flexible ureterorenoscopy and increase the stone-free rate during retrograde intrarenal surgery In this descriptive study, we presented a method for moving stones to other calyces where the need for deflection is less, using holmium fiber in cases where the nitinol basket is not available. Materials and Methods: With the “Jab and Pull” method we have described, 32 patients who underwent RIRS for symptomatic (pain or infection) renal lower calyceal stones with a diameter of 4-10 mm in our clinic, between 2012 and 2021 were retrospectively analyzed. Demographic data, stone size, Hounsfield unit, number of stones, opaque non-opaque status, stone localization, infundibulopelvic angle, perioperative-postoperative complications, and control imaging were evaluated. Results: The mean age of the patients was 51.12, and the female-male ratio was equal. The median stone size was 8mm (min:5, max:10), and the Hounsfield unit was 805 (±396.72). 75% (24) of the stones were single and 53.1% (17) were opaque. The median infundibulopelvic angle was 38 (min:19 max:52) degrees. 27 (84.4%) patients achieved stone-free status using this method. The renal lower calyx neck of two patients was too narrow, the stones of two patients were too soft, and the stone of one patient was inaccessible, preventing total success in these patients. Conclusions: In cases where a nitinol basket is needed but cannot be reached during treatment of kidney lower calyx stones, the “jab and pull” method can be considered as an alternative in suitable patients.

The fate of clinically insignificant residual fragments following retrograde intrarenal surgery and factors affecting spontaneous passage.

The remaining stone fragments after retrograde intrarenal surgery (RIRS) can lead to stone recurrence/regrowth, or stone-related events (SRE). We aimed to delineate the clinical circumstances that are decisive for spontaneous passage of clinical insignificant residual fragments (CIRF) (primary outcome) and define risk factors for stone recurrence/regrowth and their clinical manifestation (secondary outcome). A total of 115 patients who had CIRF following RIRS were included in this study. Demographic, clinical data, stone, and anatomic characteristics including infundibulopelvic angle (IPA), infundibular length (IL) and follow-up data of patients were analyzed. The mean follow-up time was 27.5 ± 6.9months. 31 (26.9%) patients passed the CIRF spontaneously. Patients were divided into two groups as spontaneous fragment passage group and fragment remaining group and compared with respect to demographic, clinical, stone-related, and anatomic characteristics. 61.2% of patients had lower pole CIRF in fragment remaining group and 83.3% of patients in spontaneous fragment passage group (p = 0.031). In addition, IPA was wider in spontaneous fragment passage group (60.7° vs 51.4°, p = 0.001). A subanalysis was performed for fragment remaining group. In 84 patients, 44 (52.4%) patients were stable for their CIRF at their follow-up and included in stable group. 40 (47.6%) patients experienced stone re-growth (27 patients) or SRE (13 patients) at their follow up. Patients in re-growth/SRE group were older (49.1 vs 39.4years, p = 0.047), had higher body mass index (28.2 vs 27kg/m2, p = 0.03) and larger CIRF (2.8 vs 2.1mm). CIRFs may be not expelled spontaneously and they may lead to additional morbidity and lithotripsy interventions.

Analysis of the Results of Extracorporeal Lithotripsy (ECL) in the Treatment of Stones of the Inferior Calcific Group (ICG): Does Variability in Calicial Anatomy Influence Them?

Introduction: Lower calyceal stones always pose a problem of optimal management: the results of ESWL are insufficient, with the possibility of generating a large quantity of residual fragments and recourse to complementary treatments. The different anatomical varieties of the lower calcific group can vary the results of treatment at this site. The objective of the study is to analyze the influence of the anatomy of the lower calyceal group (LCG) on the results of ESWL. Materials: A prospective observational study involving 57 patients with LCG stones who were treated by ESWL in our department between January 2021 December 2022 according to the French recommendations of the AFU lithiasis committee. Unfavorable LCG anatomy was defined according to Sampaio's criteria: a length of the inferior stem caliceal lower &gt;10 mm, a width&lt;5 mm and an infundibulo-pelvic angle &lt; 90º. Fragment-free rate was assessed 3 months after ESWL with tomography urography (CTU). Failure was considered as the existence of fragments ≥ 3mm, the need for ancillary procedures after ESWL (ureterscopy, RIRS, PCNL or new ESWL), complications and risk factors associated with the development of perirenal hematoma were analyzed. Results: The median age was 48,5 years (range: 22-68), with 66,66% of the participants being men (38 men and 19 women). Approximately 14,03 % (n=8) of the patients were taking antiplatelet/anticoagulant drugs, and 8,77 % (n= 5) had High blood pressure. The median size of the lithiasis was 10 mm (range: 5-20 mm), with favorable LCG anatomy observed in 45,61 % (n= 26/57) of patients, including 34,61 % (n= 9/26) who required ancillary procedures after ESWL, compared to 64,51% (n= 20/31) in patients with unfavorable anatomy (54,39 % = 31/57). The stone-free after ESWL for both groups combined was 54,38 % (n= 31/57). Auxiliary procedures included ureteroscopy or RIRS. Two perirenal hematomas were observed in patients on antiplatelet/anticoagulant therapy, with a favorable outcome. ...

The Predictive Factors for the Longer Survival of the Reusable Flexible Ureterorenoscopy.

The flexible ureterorenoscopy (FURS) is expensive and fragile equipment which easily break down during the surgery. f-URS have yet some problems with their durability that affect survival. One of the most important ways to increase the survival of a device is to improve its use in the right indications. We aimed to investigate whether the durability of the f-URS will be affected due to the volume and location of the stone and some anatomical features of the including infundibulopelvic angle (IPA), and location anomalies. The collected data from 705 patients' data including their age, sex, stone location, and stone volume, S-ReSC score, Hounsfield unit (HU) as stone density, IPA, BMI, and the usage time of f-URS using 10f-URS were included to study. Exp(B) values and confidence intervals (95% CIs) of parameters were calculated with COX regression and Roc curve analysis was also used to determine the cut-off value. Renal malformation, DJstent use, previous ESL application, and UAS use did not affect contrary to expectations stone volume, HU, IPA, and S-ReSC score were among the factors statistically significant affecting the durability of the device. It was observed, Exp(B) values of the affecting factors to be 0.984, 0.268, 0.894, and 0.607, respectively. We found the most appropriate cutoff value for IPA as 41.25 degrees. The mean stone volume broken by each of the subsequent f-URS may increase, while the mean operative time may decrease as time progresses. This result shows us the importance of mastery of the device, such as the deflection maneuver, and the correct use distance of the laser, which improves with the increase in user experience, and makes us interpret that the operation time is shortened with this self-confidence. Factors including stone volume, HU, IPA, S-ReSC score affect the durability of the f-URS device and the as well as manufacturing features.

Residual fragment size following retrograde intrarenal surgery: a critical evaluation of related variables.

Given the limited data on the predictive factors of residual kidney stone size after flexible ureteroscopy (fURS), this study aims to investigate the variables affecting residual stone size. The medical records of 642 patients without complications being treated for kidney stones with fURS between July 2014 and May 2022 were reviewed retrospectively, and the information of the 170 patients in whom residual stones were found was recorded. In addition to patient-specific factors and stone characteristics, length of postoperative hospital stay, postoperative fever, and preoperative antiaggregant use were evaluated. Of the 170 patients ultimately included in the study. The mean age was 51.56 (± 14.70). The mean stone size was 14.01mm (± 5.75), the mean residual stone size was 7.04mm (± 2.51), and the mean stone density was 829 Hounsfield units (± 395.06). The mean infundibulopelvic angle (IPA) was 49.37º (± 15.37), and 41.2% of the stones were non-opaque. The mean parenchymal thickness was 22.88mm (± 5.55). 34 patients were on antiaggregant therapy. Preoperative stone size increases in stone density and decreases in IPA were found to be correlated with increase residual stone size (p < 0.001, p < 0.001, and p < 0.001, respectively). In addition, larger residual stones were observed after the fURS procedure in patients using anticoagulants and those without hydronephrosis (p = 0.02 and p = 0.016, respectively). Use of reliable predictive factors to forecast residual stone size after fURS may help to inform those treated and enable urologists to design rational surgical strategies.

Evaluation of validity and reliability of novel rapid measurement for infundibulopelvic angle: a comparison with PACS system

ABSTRACT Background For patients with lower pole renal calculi (LPC), preoperative evaluation of infundibulopelvic angles (IPA) is of great significance; however, conventional measuring method is often inconvenient in clinical setting. Here we introduce a rapid novel method using built-in inclinometer in smartphone which is often used in anatomical parameters evaluating to implement the measurement of IPA. Materials and methods The randomized, self-controlled study on evaluating inclinometer application measured IPA on urography films collected from enrolled LPC patients. Results of statistical analysis for its validity and reliability compared to conventional PACS system are reported. Predictive performance of postoperative stone-free rates by IPA measured with the novel method was also evaluated in this study. Results Bland–Altman plot result shows that there is favorable agreement between IPA values of these two methods. The time required to utilize the PACS was considerably greater than time required to take similar measure using smartphones. The precision–recall curve (PRC) indicates that the new method has similar predictive performance for postoperative clearance rates as PACS. Conclusions In summary, measurement of IPA implemented by integrated inclinometer of smartphone is rapid, convenient, accurate and reliable in evaluating renal anatomy parameters of LPC patients.

Extracorporeal shock wave lithotripsy for lower calyx stones: predicting treatment success

IntroductionThe use of extracorporeal shock wave lithotripsy (ESWL) for lower calyx stones is associated with a high rate of residual fragments. Our aim is to analyse the effectiveness and complications of ESWL for lower calyx stones. MethodsRetrospective review of patients with lower renal calyx stones treated with ESWL between January-2014 and December-2020. Measurement of infundibular length, infundibular width and infundibulopelvic angle in lower renal pole to determine favourable anatomy. ESWL failure: fragments >3 mm detected in plain abdominal film, CT scan and/or renal ultrasound 3 months after treatment.Complications after ESWL, auxiliary procedures along with risk factors associated with perirenal haematoma were analysed. SPSS statistical software was used. Results512 patients with lower calyx stones were treated with ESWL. 80.3% of patients had a favourable anatomy. Overall stone-free rate was 70.5%. Regarding main complications after ESWL, stainstrasse was described in 5 patients and urinary tract infection in 3 patients. 10 perirenal haematomas (2%) were reported. Statistical association was found between antiplatelet treatment and the risk of perirenal haematoma (p = 0.004). Logistic binary regression proved the association between unfavourable anatomy of the lower renal pole (p = 0.000), size of the stone (p = 0.001), number of shock waves (p = 0.003), energy applied (p = 0.038) and the need for additional treatment after ESWL. ConclusionsESWL can still be considered as the initial treatment option for lower renal pole stones. The size of the stone, an unfavourable anatomy of the lower renal calyx, number of shock waves and energy applied can help predict the need for additional treatment.

Litotricia extracorpórea por ondas de choque (LEOCh) Para litiasis de grupo calicial inferior: ¿cómo predecir el éxito del tratamiento?

IntroductionThe use of extracorporeal shock wave lithotripsy (ESWL) for lower calyx stones is associated with a high rate of residual fragments. Our aim is to analyse the effectiveness and complications of ESWL for lower calyx stones. MethodsRetrospective review of patients with lower renal calyx stones treated with ESWL between January-2014 and December-2020. Measurement of infundibular length, infundibular width and infundibulopelvic angle in lower renal pole to determine favourable anatomy. ESWL failure: fragments >3mm detected in plain abdominal film, CT scan and/or renal ultrasound 3 months after treatment.Complications after ESWL, auxiliary procedures along with risk factors associated with perirenal haematoma were analysed. SPSS statistical software was used. Results512 patients with lower calyx stones were treated with ESWL. 80.3% of patients had a favourable anatomy. Overall stone-free rate was 70.5%. Regarding main complications after ESWL, stainstrasse was described in 5 patients and urinary tract infection in 3 patients. 10 perirenal haematomas (2%) were reported. Statistical association was found between antiplatelet treatment and the risk of perirenal haematoma (p=0.004). Logistic binary regression proved the association between unfavourable anatomy of the lower renal pole (p=0.000), size of the stone (p=0.001), number of shock waves (p=0.003), energy applied (p=0.038) and the need for additional treatment after ESWL. ConclusionsESWL can still be considered as the initial treatment option for lower renal pole stones. The size of the stone, an unfavourable anatomy of the lower renal calyx, number of shock waves and energy applied can help predict the need for additional treatment.

Unfavorable factors in accessing the pelvicalyceal system during retrograde flexible ureteroscopy (fURS).

Flexible ureteroscopy (fURS) is a well-established procedure for treating multiple upper-urinary tract pathologies, particularly renoureteral lithiasis. Endoscopes have undergone significant advancements, including miniaturization, improved optics, and increased maneuverability. In addition, advancements in accessory instruments, such as the performance of laser fibers, guidewires, and extraction probes, have played a significant role in improving the overall performance of flexible ureteroscopy procedures. However, despite these advancements, unique circumstances can make achieving optimum results during flexible ureteroscopy challenging. These include congenital renal anomalies (horseshoe kidneys, ectopic kidneys, rotation anomalies), as well as the unique intrarenal anatomy (infundibulopelvic angle, infundibular length) or the specifications of the endoscope in terms of maneuverability (active and passive deflection). This review explored challenging scenarios during flexible ureteroscopy procedures in the pyelocaliceal system.

Can additional variables be used to predict stone-free rates following retrograde intrarenal surgery? Anticoagulants and parenchyma thickness: a detailed examination.

The purpose of this article is to identify the factors that predict the success of retrograde intrarenal surgery (RIRS), with a focus on the effect of renal parenchymal thickness and anticoagulant use on stone-free rates. From February 2014 to April 2022, cases of kidney stones treated with RIRS at our clinic were retrospectively screened. The study included 642 cases meeting all inclusion and exclusion criteria. The patients who were observed to be stone free after a single session of RIRS were assigned to Group F, while those with residual fragments were assigned to Group R. Group F comprised 472 patients, while Group R included 170 patients. The two groups have compared certain preoperative and postoperative laboratory and radiological parameters. The infundibulopelvic angle was significantly more acute in Group R (45.63 ± 16.25 vs. 49.28 ± 15.36, p = 0.011) while patients in Group F tended to have thicker parenchyma (27.39 ± 8.38 vs. 22.88 ± 5.56, p < 0.001). In our analysis of multivariate logistic regression, stone size (OR: 1.074, 1.037-1.113; p < 0.001), lower calyceal location (OR: 0.550, 95% CI 0.364-0.831; p = 0.005), multiple numbers of stones (OR 0.254, 95% CI 0.166-0.389; p = < 0.001), the value of parenchymal thickness (OR 0.911, 95% CI 0.882-0.941; p = < 0.001) and more importantly use of anticoagulants/antiplatelets (OR 0.557, 95% CI 0.333-0.933; p = 0.026) appeared to be independent predictors of stone-free status after RIRS. Further evaluation of the data revealed that the cut-off value of the renal parenchymal thickness for an effective stone-free status in a ROC curve analysis was 24.5 with 62.9% sensitivity and 56.8% specificity (area under curve value: 0.654 [95% CI 0.608-0.699, p < 0.001]). The endourologist may be able to make more informed decisions by evaluating renal parenchymal thickness in addition to patient-related factors like anticoagulant use, which we find significantly affects outcomes, along with the stone and renal anatomy-related factors.

Single-Session Impact of High-Power Laser with Moses Technology for Lower Pole Stones in Retrograde Intrarenal Surgery: Retrospective Study

Background: This study aimed to evaluate the efficacy of a high-power holmium laser with Moses technology (MT) for the treatment of lower pole stones during retrograde intrarenal surgery (RIRS). Methods: Herein, 305 patients with lower pole stones who underwent RIRS using a high-power holmium laser with MT were retrospectively classified into the stone-free (SF) and non-SF groups. We measured the stone burden, stone volume, stone hardness, pre- or post-operative stent placement, infundibulopelvic angle (IPA), infundibular width (IW), infundibular length (IL), and calyceal pelvic height in terms of pelvicalyceal anatomy using retrograde pyelograms and evaluated the predictive factors of postoperative SF. Results: A total of 173 (56.7%) and 229 (75.1%) patients achieved a SF status on postoperative day one and at one month, respectively. Operation time in the SF group was shorter than that in the non-SF group (51.0 vs. 74.5 min). There were no significant differences in postoperative complications between the SF and non-SF groups. Significantly predictive risk factors in postoperative SF included total stone volume (odds ratio (OR), 1.056; 95% CI, 1.015-1.099; p = 0.007), IPA (OR, 0.970; 95% CI, 0.956-0.993; p = 0.009), and IW (OR, 0.295; 95% CI, 0.121-0.718; p = 0.007). The cut-off values of stone volume, IPA, and IW were 515.2 mm3, 46.8°, and 7.75 mm, respectively. Conclusions: A high-power holmium laser with MT in lower pole stones is a valuable option for positive outcomes and patient's safety. Larger stone volume, acute IPA, and narrow IW were negative predictors related to postoperative SF status.

A Scoring System for Optimal Selection of Endoscopic Treatment for 1-2cm Lower Pole Renal Calculi.

To explore the establishment of a scoring system that can provide a reference for clinical decision making regarding the endoscopic treatment of 1-2 cm lower pole stones (LPS). The data of patients with renal calculi who were treated with percutaneous nephrolithotomy (PCNL) or retrograde intrarenal surgery (RIRS) in three hospitals from January 2013 to December 2017 were analyzed retrospectively. Multivariable logistic analysis was performed to determine the statistically significant indicators and regression coefficients, which were used to construct the scoring system. The stone-free rate (SFR) and postoperative complication rates of PCNL and RIRS within the two fractional segments of the scoring system were compared to select the optimal procedures. A total of 137 patients in the PCNL group and 152 patients in the RIRS group were included in this study. Five factors were found to be most predictive of endoscopic treatment choice: stone number, stone diameter, infundibulopelvic angle (IPA), infundibular length (IL), and infundibular width (IW), yielding a total score ranging from 0-5. In the 0-2 segments, the RIRS group had better outcomes than the PCNL group in terms of the postoperative complication rates (6.8% versus 18.0%, P = .026). In segments 3-5, the SFR of the PCNL group was significantly higher than that of the RIRS group (88.5% versus 70.6%, P = .017). Our scoring system was based on the patient's preoperative imaging examination to measure the stone number, stone diameter, IPA, IL and IW. RIRS was recommended at 0-2 segments, and PCNL was recommended at 3-5 segments. This new scoring system is expected to provide guidance for urologists to make endoscopic treatment decisions for 1-2 cm LPS.

Pelvicalyceal anatomy on the accessibility of reusable flexible ureteroscopy to lower pole calyx during retrograde intrarenal surgery.

This study aimed to evaluate the pelvicalyceal anatomy on accessibility of reusable flexible ureteroscopy (fURS) to the lower pole calyx during retrograde intrarenal surgery (RIRS). Here, 854 patients with ureteral or kidney stones with access to a renal collecting system using reusable fURS were classified into either the accessible group, in whom the deepest lower pole calyces could be touched; and the inaccessible group, in whom the deepest lower calyces could not be touched. We measured the infundibulopelvic angle (IPA), infundibular width (IW), infundibular length (IL), and calyceal pelvic height (CPH) using retrograde pyelograms and performed intergroup comparisons. The median IPA, IW, IL, and CPH in the accessible and inaccessible group were 60.5° and 45.6° (p < 0.001), 10.8 and 9.4 mm (p < 0.001), 33.2 and 36.4 mm (p < 0.001), and 25.9 and 30.9 mm (p < 0.001), respectively. IPA (OR 0.963, 95% CI 0.952-0.974, p < 0.001) and IW (OR 0.519, 95% CI 0.331-0.816, p=0.004) were significant risk factors of renal pelvicalyceal anatomy related to the accessibility of the lower pole calyces. The cut-off value for IPA and IW was 45.8°(p < 0.001) and 7.8 mm (p < 0.001), respectively. IPA < 45.8° and IW <7.8 mm were negative predictors to access the lower pole calyces when using reusable fURS during RIRS.