Lower Pole Stones Are Associated with Low Stone-Free Rates in Retrograde Intrarenal Surgery: A Myth or Fact? - A Matched Case-Control Study from the RIRSearch Group.

INTRODUCTION: There are conflicting results in the literature regarding the efficacy of retrograde intrarenal surgery (RIRS) in lower pole stones. This study aimed to evaluate RIRS outcomes in lower pole stones by forming matched case-control groups. METHODS: The data of 491 patients who were diagnosed with kidney stones and underwent RIRS were retrospectively included in the study. A total of 209 patients with lower pole stones (Group 1) and 282 patients with pelvic stones (Group 2) were matched at a 1:1 ratio in terms of stone burden, stone density, preoperative double-J stenting status, and a previous history of shock wave lithotripsy, yielding 159 patients in each group. A computed tomography scan was performed to evaluate the stone-free status. The primary outcome was stone-free status 1 month after RIRS. RESULTS: After case-control matching, the median age was 49 years (interquartile range [IQR]: 40-58) in Group 1 and 50 years (IQR: 35-60) in Group 2 (p = 0.388). The median stone burden values of Group 1 and Group 2 were 415.3 mm3 (IQR: 176.1-858.2) and 503.3 mm3 (IQR: 282.5-864), respectively (p = 0.100). After RIRS, stone-free status was achieved by 126 of the 159 (79.2%) in Group 1 and 133 of the 159 (83.6%) patients in Group 2 (p = 0.387). The groups were similar in terms of perioperative complications (4.4% in Group 1 and 3.8% in Group 2, p = 0.777), postoperative complications (13.8% in Group 1 and 10.3% in Group 2, p = 0.393), and median operation time (60 min in both, p = 0.230). A longer median fluoroscopy time was noted in Group 1 compared to Group 2 (26 s and 3 s, respectively, p = 0.013). CONCLUSIONS: Stone-free rates and complications were comparable between the patients with lower pole and pelvic stones after RIRS. However, lower pole stones are associated with longer fluoroscopy time. RIRS can be performed effectively for the treatment of lower pole stones.

The Efficacy and Safety of Retrograde Intrarenal Surgery in Elderly Patients: A Propensity Score Matching Study by the RIRSearch Group.

INTRODUCTION: The aim of the study was to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) in elderly patients by comparing them with propensity score-matched age-groups. METHODS: Patients who underwent RIRS to treat upper urinary tract stone disease at seven centers were included in the study and were divided into four groups. The age intervals of the patients in group 1, group 2, group 3, and group 4 were 18-29 years old, 30-49 years old, 50-64 years old, and over 65 years old, respectively. Propensity score matching analysis was used to homogenize the groups in terms of demographic and clinical properties. Operative results, preoperative complications, perioperative complications, postoperative complications, duration of hospitalization time, and stone-free status were compared between groups. RESULTS: A total of 1,017 patients were included in the study. There were 69 (9.9%) patients in group 1, 324 (46.5%) in group 2, 217 (31.1%) in group 3, and 87 (12.5%) in group 4 after propensity score matching. The operation time and postoperative complication rates were significantly different among groups, whereas the hospitalization time, perioperative complication rates, and stone-free status were similar. The operation time was significantly higher in patients over 65 years old (p = 0.001). The postoperative complication rates were significantly higher in group 1 with Clavien I-II complication predominance (p = 0.003). CONCLUSION: The efficacy and safety of RIRS did not change with aging, and RIRS was an effective option for the treatment of upper urinary system stones in elderly patients.

Retrograde Intrarenal Surgery Learning Curves of Urology Residents Supervised by an Experienced Endourologist: An RIRSearch Study.

INTRODUCTION: Although retrograde intrarenal surgery (RIRS) is being performed with increasing frequency, there are only a limited number of studies about the learning curve (LC). This study aimed to analyze the LC of RIRS for five surgeons who underwent the same training. MATERIALS AND METHODS: The data of the 410 patients who underwent RIRS between April 2017 and 2022 in a single institution, which were performed consecutively by five surgeons, were analyzed. All 50 cases performed by each surgeon were included and numbered consecutively and separately, according to the date of the operation. The combined stone-free rate (SFR) was calculated for each surgeon's cases in the same row, and the LCs were created using moving average and cumulative sum (CUSUM) analyses. Separate multivariable analyses identified each period's (LC vs. beyond) characteristics. RESULTS: The LCs from the combined SFRs reached a plateau after approximately 50 cases for both the CUSUM and the moving average. The effect of stone burden on SFR was more evident in the first 50 cases compared to subsequent cases in the multivariable analyses (p = 0.001 and p = 0.047, respectively). Case order and stone density were independent factors in the first 50 cases (OR: 1.02 [95% CI 1.00-1.04], p = 0.04 and OR: 0.99 [95% CI 0.99-1.00], p = 0.04) but not significant in subsequent cases (OR: 0.97 [95% CI 0.94-1.00], p = 0.1 and OR: 1.00 [95% CI 0.99-1.00], p = 0.7, respectively). Compared to single locations except the lower calyx, the unfavorable effect of the multiple-stone localization on SFR grew in strength after the 50th case (OR: 0.42 [95% CI 0.23-0.78], p = 0.01 and OR: 0.20 [95% CI 0.09-0.46], p < 0.001, respectively). CONCLUSIONS: This is the first study reporting on the RIRS LCs of urology residents. While stone burden, density, and multiple-stone localization were the factors determining SFR in the learning period, after completing the LC, the effect of stone burden weakened and multiple-stone localization became stronger.

Does extracorporeal shock wave lithotripsy before retrograde intrarenal surgery complicates the surgery for upper ureter stone? The results of the RIRSearch group.

AIMS: To evaluate the effect of pre-RIRS ESWL on the efficiency and safety of RIRS in the treatment of proximal ureter stones. METHODS: The patients in the study population were divided into two groups. Group-1 was composed of patients who had undergone ESWL for proximal ureter stones before RIRS and Group-2 was composed of patients who directly underwent RIRS without any prior ESWL. The clinical and demographic properties of the patients were analysed in the RIRSearch database. The operative outcomes, peroperative complications, postoperative complications, hospitalisation time and stone-free rates were compared between the groups. RESULTS: There were 56 patients in Group 1 and 95 patients in Group 2. The demographic and clinical properties were similar between the groups. The stone-free rates, peroperative complications and postoperative complications were also similar between the groups; however, the fluoroscopy time was significantly higher in Group 1 (P = .043). The cut-off duration of 10 weeks between ESWL and RIRS had reasonable/favourable discriminating ability, with a 51% sensitivity and 88% specificity rate for stone-free status. CONCLUSION: Performing ESWL on the proximal ureter stones before RIRS did not change the efficacy and safety of RIRS. The time between the patient's last ESWL session and RIRS had a predictive value for stone-free status, but did not have any effect on complications.

The effect of optical dilatation before retrograde intrarenal surgery on success and complications: Results of the RIRSearch group study.

AIM: The guidelines propose optical dilatation before retrograde intrarenal surgery (RIRS), but there are currently no evidence-based studies concerning the impact of optical dilatation with semirigid ureteroscopy (sURS). The aim of this study was to evaluate the effect of optical dilatation through sURS prior to the RIRS procedure on the success and complications of RIRS. METHODS: A total of 422 patients were included in the retrospective multicentre study. The patients were divided into two groups according to whether sURS was to be performed. Patients' demographics, stone parameters and operative outcomes were compared. Surgical success was defined as no or up to 3-mm residual stone fragments without the need for additional procedures. The independent predictors for surgical success were determined with a multivariable logistic regression model. RESULTS: Of the 422 patients, 133 (31.5%) were in the sURS group and 289 (68.5%) were in the non-sURS group. Stone characteristics and patients' demographics were similar between the groups. Operation time in the sURS group was significantly longer (compared with the non-sURS group, P < .0001). A ureteral access sheath (UAS) could not be placed in four (3.0%) patients in the sURS group, nor in 25 (8.7%) patients in the non-sURS group (P = .03). Compared with the non-sURS group, the intraoperative complication rate was lower in the sURS group (14 [4.8%] vs 1 [0.8%], P = .04). The surgical success rate was higher in the sURS group (P = .002). Nevertheless, sURS had no independent effect on surgical success. We found two independent predictors for surgical success rate: stone number (P < .0001, OR:2.28) and failed UAS placement (P = .035, OR:3.49). CONCLUSIONS: Optical dilatation with sURS before RIRS increases surgical success by raising the rate of UAS placement and reducing the rate of intraoperative complications. We suggest that this method can be routinely applied to patients who have not been passively dilated with a JJ stent.

Evaluation with Decision Trees of Efficacy and Safety of Semirigid Ureteroscopy in the Treatment of Proximal Ureteral Calculi.

PURPOSE: The decision on the choice of proximal ureteral stone therapy depends on many factors, and sometimes urologists have difficulty in choosing the treatment option. This study is aimed at evaluating the factors affecting the success of semirigid ureterorenoscopy (URS) using the "decision tree" method. MATERIALS AND METHODS: From January 2005 to November 2015, the data of consecutive patients treated for proximal ureteral stone were retrospectively analyzed. A total of 920 patients with proximal ureteral stone treated with semirigid URS were included in the study. All statistically significant attributes were tested using the decision tree method. RESULTS: The model created using decision tree had a sensitivity of 0.993 and an accuracy of 0.857. While URS treatment was successful in 752 patients (81.7%), it was unsuccessful in 168 patients (18.3%). According to the decision tree method, the most important factor affecting the success of URS is whether the stone is impacted to the ureteral wall. The second most important factor affecting treatment was intramural stricture requiring dilatation if the stone is impacted, and the size of the stone if not impacted. CONCLUSIONS: Our study suggests that the impacted stone, intramural stricture requiring dilatation and stone size may have a significant effect on the success rate of semirigid URS for proximal ureteral stone. Further studies with population-based and longitudinal design should be conducted to confirm this finding.

Attenuation of partial unilateral ureteral obstruction - induced renal damage with hyperbaric oxygen therapy in a rat model.

OBJECTIVE: The objective of the present study was to evaluate the effectiveness of HBO therapy on biochemical parameters, renal morphology and renal scintigraphy in rats undergoing chronic unilateral partial ureteral obstruction (UPUO). MATERIAL AND METHODS: Thirty-five rats were divided into five equal groups: Control group; Sham group; HBO group; UPUO group and UPUO/HBO group. The effects of HBO therapy were examined using biochemical parameters and histopathological changes. After calculating the score for each histopathological change, the total histopathological score was obtained by adding all the scores. In addition, dynamic renal scintigraphy findings were evaluated. RESULTS: Serum parameters indicating inflammation, serum tumor necrosis factoralpha, ischemia modified-albumin, IMA/albumin ratio and Pentraxin-3 levels, were observed to be high in the UPUO group and low in the UPUO/HBO treatment group. Similarly, in the treatment group, the reduction in malondialdehyde, total oxidant status and oxidative stress index levels and increase in total antioxidant capacity values were observed to be statistically significant compared to the UPUO group (p<0.001, p=0.007, p<0.001, p=0.001, respectively). The total score and apoptosis index significantly decreased after administration of HBO treatment. Dynamic 99mTc-MAG3 renal scintigraphy also showed convincing evidence regarding the protective nature of HBO against kidney injury. In the UPUO/HBO therapy group, the percentage contribution of each operated kidney increased significantly compared to the UPUO group (41.73% versus 32.72%). CONCLUSION: The findings of this study indicate that HBO therapy had a reno-protective effect by reducing inflammation and oxidative stress, and preserving renal function after renal tissue damage due to induction of UPUO.

Pudendal neuralgia after pelvic surgery using mesh: Case reports and laparoscopic pudendal nerve decompression.

Persistent pain after vaginal mesh surgery is a rare and agonizing entity that has devastating consequences for the patient's quality of life. Many etiologies have been blamed including nerve injuries and entrapments. Pudendal neuralgia is a rare chronic neuropathic pain syndrome in the anatomical territory of the pudendal nerve. Various treatment options, such as medication management, physiotherapy, nerve blocks, decompression surgery and neuromodulation, have been used, but the most appropriate treatment for pudendal neuralgia has not yet been determined. In this article, we present two cases of postoperative pelvic pain thought to be secondary to injury or mechanical distortion of the pudendal nerve after rectocele repair using mesh and tension-free vaginal tape sling. In cases of failed conservative treatment and of mesh removal surgery, laparoscopic pudendal nerve decompression and omental flap wrapping operation can be a treatment option for pudendal neuralgia.

Protective effect of syringic acid on kidney ischemia-reperfusion injury.

The objective of the present study was to determine whether preischemic administration of syringic acid (SA) would attenuate renal ischemia-reperfusion injury (IRI). Rats were divided into three groups: Sham group; IR group; and IR + SA group. The effects of SA were examined using biochemical parameters including serum ischemia-modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), tissue superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and malondialdehyde (MDA). The apoptosis status and histopathological changes were evaluated. After calculating the score for each histopathological change, the total score was obtained by summing all the scores. In the SA group, MDA, IMA, TOS, and OSI decreased significantly compared to the IR group. After SA administration, the increase in GPx activity was found to be significant. Apoptosis decreased significantly in the SA group compared with the IR group. The total score significantly decreased after administration of SA. Taken together, our findings suggest that SA preconditioning is effective in reducing tissue damage induced in kidney IRI. Renal histology also showed convincing evidence regarding the protective nature of SA.

The effect of music therapy during shockwave lithotripsy on patient relaxation, anxiety, and pain perception.

OBJECTIVES: To research the effect of listening to music during shock wave lithotripsy (SWL) on the patient's pain control, anxiety levels, and satisfaction. PATIENTS AND METHODS: The study comprised 400 patients from three hospitals. Half of patients listened to music during their first SWL session but not during their second session. The other half had no music for the first session but the second session was accompanied by music. During all sessions, with and without music, pulse rates, blood pressure, State-Trait Anxiety Inventory-State Anxiety scores (STAI-SA), Visual Analog Scale (VAS scores for pain), willingness to repeat procedure (0 = never to 4 happily), and patient satisfaction rates (0 = poor to 4 = excellent) were assessed. RESULTS: There was no statistical difference between the two groups in terms of blood pressure and pulse rates. In both groups, the STAI-SA and VAS pain scores were lower in the session when music was listened to (p < 0.001). The patients requested more SWL treatment be completed while listening to music and their satisfaction was greater. CONCLUSION: Music lowered the anxiety and pain scores of patients during SWL and provided greater satisfaction with treatment. Completing this procedure while the patient listens to music increases patient compliance greatly and reduces analgesic requirements.

The association of urolithiasis and androgenetic alopecia.

OBJECTIVES: The objective of this study is to investigate whether patients with androgenetic alopecia were at risk in terms of urinary system stone disease. PATIENTS AND METHODS: Patients with no baldness (Hamilton-Norwood Scala [HNS] stage I) were categorized as Group I, those with hair loss in the frontal region (HNS stages II, III, IIIa, and IVa) as Group II, those with hair loss in the vertex region (HNS stage III-vertex, V) as Group III and those with hair loss in both vertex and frontal regions (HNS stages IV, Va, VI, and VII) as Group IV. Patients in all groups were compared in terms of presence of stone, and the presence of any association between alopecia and urolithiasis, with common etiological risk factors, was investigated. RESULTS: Three hundred and two male patients were included in the study. The presence of urolithiasis was detected in 28.9% of patients in Group I; 26.5% of Group II; 36.9% of Group III; and 44.4% of Group IV (p = 0.085). Among patients aged under 60, urinary stone disease was detected in 30.8% of patients in Group I; 26.4% of Group II; 41.2% of Group III; and 53.8% of Group IV (p = 0.001). In patients aged over 60, urolithiasis was detected in 12.5% of patients in Group I; 26.9% of Group II; 32.2% of Group III; and 37.8% of Group IV (p = 0.371). CONCLUSIONS: We determined a significant correlation between vertex pattern and total alopecia with urolithiasis in patients younger than 60 years old.

The effect of breastfeeding on spontan resolution of monosymptomatic enuresis.

PURPOSE: The aim of this study was to examine whether the duration of breastfeeding during infancy was associated with the time of spontaneous resolution of monosymptomatic enuresis (SRME). MATERIALS AND METHODS: A total of 1500 people were surveyed at four centers. One hundred and eighty-one people with a history of monosymptomatic enuresis (ME) who received no treatment and had no day time symptoms were included in the study. The relationship between the duration of breastfeeding and SRME was assessed by considering the duration of breastfeeding as both continuous and categorical (cut-off value 5 months) variable. The multivariate general linear model was used to identify independente predictors such as gender, family history, and educational status of parents. RESULTS: Pearson correlation analysis of the age of SRME and duration of breastfeeding found no statistically significant relationship. However, there was a significant difference in the age of SRME of those who were breastfed for 5 months or less compared to those who were breastfed for more than 5 months. According to the multivariate analysis, gender and educational status of parents were not effective on the age of SRME. Stepwise linear regression model showed that breastfeeding for five months or less and family history could affect the age of SRME. The regression formula was: age of SRME=9.599 + (3.807×five months or less of breastfeeding) + (1.258×positive family history). CONCLUSIONS: It was found that when breastfeeding lasted for more than 5 months, there was a positive contribution to SRME.

Association of congenital left renal vein anomalies and unexplained hematuria: multidetector computed tomography findings.

OBJECTIVES: To investigate whether congenital renal vein anomalies are involved in the etiology of hematuria by analyzing abdominal multidetector computed tomography (MDCT) results. METHODS: Six hundred and eighty patients undergoing MDCT for various abdominal pathologies in whom possible causes of hematuria were excluded were retrospectively assessed in terms of left renal vein anomalies, such as circumaortic left renal vein (CLRV), retroaortic left renal vein (RLRV) and multiple renal vein (MRV). Patients with CLRV, RLRV or MRV and patients with normal left renal veins were compared in terms of the presence of hematuria. RESULTS: Left renal vein anomalies were detected in 100 patients (14.7%). RLRV, CLRV and MRV were identified in 5.4, 2.5 and 6.8% of patients, respectively. Hematuria was determined in 8.1% of patients with an RLRV anomaly and in 10.5% of patients with no RLRV anomaly (p=0.633). Hematuria was detected in 23.5% of patients with a CLRV anomaly and 10.1% of those without (p=0.074), and in 21.7% of patients with an MRV anomaly and 9.6% of those without (p=0.009). CONCLUSIONS: In addition to increasing risk of complication during retroperitoneal surgery, numeric congenital renal vein anomalies are also significant in terms of leading to clinical symptoms such as hematuria.

Accuracy of unenhanced computerized tomography interpretation by urologists in patients with acute flank pain.

PURPOSE: The aim was to compare the findings of non-contrast computerized tomography (NCCT) evaluated by urology specialists with the findings of experienced radiologists, who are accepted as a standard reference for patients who present with acute flank pain. MATERIALS AND METHODS: Five hundred patients evaluated with NCCT were included in the study. The NCCT images of these patients were evaluated by both radiologists and urology specialists in terms of the presence of calculus, size of calculus, the location of calculus, the presence of hydronephrosis, and pathologies other than calculus, and the results were compared. RESULTS: The evaluations of urology specialists and standard reference radiology specialists are consistent with each other in terms of the presence of calculus (kappa [κ]: 0.904), categorical stone size (κ: 0.81), the location of calculus (κ: 0.88), and hydronephrosis (κ: 0.94). However, the evaluations of urology specialists in detecting pathologies other than calculus, which may cause acute flank pain or accompany renal colic, were found to be inadequate (κ: 0.37). The false-negative rate of detecting pathologies outside of the urinary system by the urology specialists is calculated as 0.86. CONCLUSION: Although the urology specialists can evaluate the findings related to calculus sufficiently with NCCT, they may not discover pathologies outside of the urinary system.

The Time of Spontaneous Resolution of Monosymptomatic Nocturnal Enuresis (MNE) Is Familial.

PURPOSE: To investigate whether or not the age of spontaneous resolution of monosymptomatic nocturnal enuresis (MNE) was familial. PATIENTS AND METHODS: A questionnaire was administered to more than 1,500 people, and 100 appropriate participants were identified from four referral hospitals. We included the participants who had MNE and whose parents also had MNE with spontaneous resolution. Then the association between the spontaneous resolution time of MNE in parents and that in their children was investigated. RESULTS: The mean ages of spontaneous resolution were 10.7 (10-30 years), 9.4 (6-17 years) and 10.9 (6-18 years) in participants, their mothers and their fathers, respectively. According to the statistical analysis, there was a positive correlation between participants and both their mothers and fathers (p < 0.05). In addition, it was revealed that familial MNE history based on first- and second-degree relatives, in addition to their parents, was also associated with the increased spontaneous resolution age of MNE (p < 0.05). According to our results, gender and parents' education status were not statistically associated with the spontaneous resolution (p > 0.05). CONCLUSION: As a conclusion, the age of spontaneous resolution of MNE is familial. Although the exact reasons of spontaneous resolution still remain a mystery; further genetic investigations may be able to resolve this mystery.

Do Hypertension, diabetes mellitus and obesity increase the risk of severity of nephrolithiasis?

OBJECTIVE: In this study we planned to investigate the relationship between presence of kidney stones and stone burden with hypertension (HT), diabetes mellitus (DM) and body mass index (BMI). METHODS: A total of 574 patients were included in the study. None of the patients had a history of stones. The 121 patients with kidney stone identified on ultrasound evaluation and the 453 patients with no stones were compared in terms of HT, BMI and DM. The stone burden of 121 patients with diagnosed stones was compared in terms of the same variables. RESULTS: Of the 121 patients with kidney stones 30 (24.7%) had HT, while 66 (14.5%) of the 453 patients without stones had HT (p=0.007). BMI values of those with and without stones were 27.2 ± 4.93 kg/m(2) and 25.29 ± 4.12 kg/m(2), respectively (p<0.001). Twenty-five (20.6%) of the patients with stones diagnosed by ultrasound had DM, while 49 (10.8%) of those without stones had DM (p=0.004). When comparing patients with and without kidney stones, logistic regression analysis revealed that DM (odds ratio [OR] 2.06, 95% confidence interval [CI] 1.17 to 3.63, p=0.013) and BMI (OR 1.08, CI 1.03 to 1.13, p=0.003) were independently associated with presence of stones. No significant relationship was found between the same variables and cumulative stone diameter (CSD) and stone surface area (SA) evaluated for stone burden. CONCLUSIONS: While diabetes mellitus, Hypertension and increased Body Mass Index may add to the possibility of stone formation, they did not affect stone burden.

Comparison of individuals consuming natural spring water and tap water in terms of urinary tract stone disease.

OBJECTIVES: To compare individuals consuming natural spring water and tap water in terms of presence of urinary tract stone disease. PATIENTS AND METHODS: Patients were divided into two groups on the basis of the type of water: tap water (Group I) vs natural spring water consumers (Group II). The two groups were compared in terms of presence of urolithiasis. In addition to the type of water consumed, participants were investigated in terms of age, sex, occupation, body mass index (BMI) and presence of hypertension (HT) and diabetes mellitus in order to evaluate if they constituted a risk factor for urolithiasis. RESULTS: Two hundred fifty-nine patients consuming tap water and 254 consuming natural spring water were included in this study. Presence of urinary stone disease was determined in 27% of patients in Group I and 26% of Group II (p = 0.794). At multivariate analysis involving all variables that might be correlated with the presence of urolithiasis; male gender, high BMI and presence of HT emerged as being significantly associated with urolithiasis. CONCLUSIONS: Although we showed that male gender, presence of HT and high BMI affect stone formation, no difference was demonstated in terms of presence of stone among patients consuming tap or natural spring water.

The Effect of Ureteral Access Sheath Use/Caliber Change on Outcomes of Retrograde Intrarenal Surgery, Short-Term Kidney Functions, Radiation Exposure, Ureteroscope Lifetime, and Factors Predicting Insertion Failure: A RIRSearch Study.

Background: The aim of this study was (1) to explore effect of ureteral access sheath (UAS) use on primary retrograde intrarenal surgery (RIRS) outcomes, short-term kidney functions, radiation exposure, and ureteroscope lifetime (URS-LT) and (2) to reveal factors that predict UAS insertion failure. Materials and Methods: Patients (n = 1318) who underwent RIRS without UAS (Group 1), those who had operation with a <11-13 Fr (Group 2), and those with a ≥11-13 Fr UAS were matched (1:1:2) and compared. Stone-free rate (SFR), intra- and postoperative complications, acute kidney injury (AKI), fluoroscopy time, URS-LT, and UAS insertion failure were the outcomes. Results: SFR, which was highest in Group 3 (75%, 71% and 87.3%, respectively; P = .001), was significantly associated with use of ≥11-13 Fr (odds ratio [OR]: 4.2, P < .001), but was not with use of <11-13 Fr UAS (OR: 1.3, P = .3). Group 3 had less need for auxiliary procedure (15%, 16%, and 7.4%, respectively; P = .03). Five percent of patients had a risk of AKI, but only 0.3% developed AKI. Although UAS use was protective against creatinine increase (OR: 0.65, P = .02), increased risk of AKI was only associated with female gender (OR: 5.5, P < .001). Fluroscopy times were 5, 15, and 87 sn, respectively (P < .001). Short URS-LT was strongly associated with high frequency of lower calix stones (r = -0.94, P = .005), but URS-LT was not correlated with sheathless case rate (r = 0.59, P = .22). UAS insertion success in first attempt was more likely in younger (OR: 0.99, P = .03), hydronephrotic (OR: 3.4, P < .001), and female cases (OR: 1.5, P = .008). But absolute UAS insertion failure was associated with female gender (OR: 2.7, P = .017). Conclusions: Not any UAS use but a higher caliber UAS use may improve SFR and protect against AKI after RIRS. Although UAS insertion failure is seen mostly in men, it may be more challenging in women owing to less efficacy of preoperative Double-J stent.

Safety and Efficacy of Retrograde Intrarenal Surgery in the Solitary Kidney: A Propensity Score-Matched Analysis of the RIRSearch Study Groups' Results.

Background: The aim of this study was to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) in patients with renal calculi with solitary kidneys (SKs). Materials and Methods: In this retrospective, multicenter study, a matched case-control study was carried out using the data from 522 RIRS patients treated between 2014 and 2021. Patients' demographic data, stone characteristics, operative outcomes, perioperative and postoperative complications, and surgical success were analyzed. All patients were evaluated with noncontrast-enhanced computed tomography (NCCT) preoperatively and 1 month after the surgery. Surgical success was defined as no evidence of remaining residual fragments of <3 mm in the first-month postoperative NCCT images. The case group of 29 patients with SKs (Group 1) treated with RIRS were matched with 76 control patients (Group 2) with bilateral kidneys, who underwent unilateral RIRS by propensity score-matched (PSM) analysis. Results: After PSM analysis, the demographic and clinical data did not differ significantly between the groups. The stone burden was similar between the groups: 733.6 mm3 (range: 50.4-7565.9) versus 991.1 mm3 (range: 201.2-4380.6) (P = .09), respectively. The perioperative complication rates were 13.8% (n = 4) in Group 1 and 11.8% (n = 9) in Group 2 (P = .78). There was no statistically significant difference between the groups for postoperative complication rates (minor complications, classified as Clavien 1 or 2), (6.9% [n = 2] versus 13.2% [n = 10; P = .34]), respectively. Surgical success was 82.8% (n = 24) in Group 1 and 83.6% in Group 2 (P = .92). There was no significant difference between preoperative and postoperative glomerular filtration rate and creatinine values (P = .005). Conclusions: Our results support that RIRS is a safe and effective treatment method in SK patients with similar complication and stone-free rates compared to patients who had bilateral functional kidneys and underwent unilateral RIRS.

Is Psoas Muscle Mass Associated with Failure of Ureteral Access Sheath Insertion and Complications from Retrograde Intrarenal Surgery? A Case-Control Study from RIRSearch group.

Objective: To investigate the association between psoas muscle mass (PMM) and failure of ureteral access sheath (UAS) insertion and complications from retrograde intrarenal surgery (RIRS). Materials and Methods: A multicenter retrospective case-control study was conducted that included patients who underwent RIRS despite failure of UAS insertion (Cohort 1) and confounder-matched control patients who underwent RIRS after successful UAS insertion (Cohort 2). For morphometric analysis of PMM, ipsilateral psoas muscle areas (iPMAs) were measured using the coreslicer.com webkit. After comparing demographic, clinical, and complication rates and iPMAs between cohorts, gender-specific median iPMAs were also determined to further subdivide patients in each cohort as either low iPMAs or high iPMAs. Thereafter, patients were also compared in terms of RIRS complications. Results: Cohort 1 included 86 patients whereas Cohort 2 consisted of 124 matched cases. The median (interquartile range) iPMAs were similar between the cohorts: Cohort 1, 11.05 (6.82-14.44) cm2 versus 11.12 (6.97-13.69) cm2 for Cohort 2 (P ˃ .05). There was a significant inverse relationship between iPMAs with age (r = -0.222) and Charlson comorbidity index (r = -0.180) for all patients (P ˂ .05). Perioperative and postoperative complication rates were 8.1% and 16.3% for Cohort 1 and 6.5% and 21% for Cohort 2, respectively. The complication rates were not statistically different between patients with high iPMAs and those with low iPMAs, in male or female patients (P > .05). Conclusions: These results show that failure of UAS was not associated with PMM. Furthermore, since the complication rates were similar between patients with high PMM and low PMM, RIRS may be a reliable treatment choice for sarcopenic patients as well as in nonsarcopenic patients.