Ureteral stent after PCNL: is leaving the threads through the percutaneous tract safe and better tolerated?

OBJECTIVE: To assess safety, urinary symptoms, and feasibility of JJ stent removal with exteriorized threads through the percutaneous tract after percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: Prospective, transversal, comparative, experimental, randomized 1-to-1 cohort study in 52 patients who underwent "tubeless" PCNL from October 2020 to November 2022. Group A with threads through the urethra and Group B through the percutaneous tract. The validated USSQ (Ureteral Stent Symptom Questionnaire) was applied in the Urology office a week after the procedure, and the JJ stent was withdrawn by pulling the threads. Hemoglobin and urine culture, and pre- and post-surgery were evaluated. RESULTS: There is a statistically significant difference in favor of group B when comparing urinary symptoms (p = 0.008), body pain (p = 0.009), and general condition (p = 0.042), mainly for non-urgency incontinence, frequency of analgesic use, and dysuria. There were significant differences between groups (p = 0.028, p = 0.026, p = 0.027, respectively). There is no association with urinary infections (p = 0.603) nor an increased risk of bleeding (p = 0.321). CONCLUSION: The removal of the JJ stent with exteriorized threads through the percutaneous tract after PCNL in the office is a feasible and safe procedure if it is removed before 8 days and has better tolerance regarding the urinary symptoms.

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.

Percutaneous nephrolithotomy for adult renal transplant de novo graft lithiasis: a single center analysis and systematic review of the literature.

INTRODUCTION/OBJECTIVE: Graft stones in renal transplant recipients pose a unique challenge, finding effective interventions to ensure optimal graft function and patient well-being. Various methods of stone clearance have been described for graft stones, including percutaneous nephrolithotomy (PCNL). While PCNL is a promising approach for managing graft stones, specific outcomes and associated characteristics for this approach have not been comprehensively evaluated before. This study aims to evaluate the safety and efficacy of the use of PCNL as the primary intervention of graft stones by assessing stone-free rates (SFR), treatment impact on graft function, and perioperative complications. METHODS: A retrospective clinical audit was performed for all transplants performed in a single center from 2007 to 2022, which included all graft lithiasis patients who were treated with PCNL. Both perioperative parameters and post-operative outcomes were collected. In addition, a systematic review including articles from MEDLINE, Embase, Web of Science yielded 18 full-text articles published between 1/1/2000 and 15/11/2023. The results pertaining to patients who underwent PCNLs for graft stones were cross-referenced and thoroughly evaluated. The review encompassed a comprehensive analysis of clinical data, postoperative outcomes, and procedural details. The protocol for the systematic review was prospectively registered on PROSPERO (CRD42023486825). RESULTS: In our center, 6 graft lithiasis patients were treated with PCNL. The initial SFR was 83.3%. SFR at 3 months and 1 year were both 100.0%. SFR at 3 years was 66.7%. Other centers reported initial SFR of 82.6-100.0% (interquartile range). SFR at 3 months, 1 year, 3 years was not well reported across the included studies. Incidence of graft lithiasis ranged from 0.44%-2.41%. Most common presentations at diagnosis were oliguria/anuria/acute kidney injury and asymptomatic. Reported complications included blood loss, transient hematuria, high urine output, sepsis, and damage to surrounding structures. The most commonly reported metabolic abnormalities in transplant lithiasis patients included hyperuricemia and hyperparathyroidism. CONCLUSION: PCNL is a practical and efficient choice for addressing graft lithiasis, demonstrating excellent stone clearance and minimal perioperative complications. These findings show the importance of PCNL as a primary intervention in this complex patient population.

Super-mini PCNL (SMP) with suction versus standard PCNL for the management of renal calculi of 1.5 cm-3 cm: a randomized controlled study from a university teaching hospital.

PURPOSE: To assess the safety and efficacy of super-mini PCNL (SMP, 14 Fr) when compared to standard PCNL (sPCNL, 24-30 Fr) in the management of renal calculi of size ranging from 1.5 to 3 cm. METHODS: From February 2021 to January 2022, a total of 100 patients were randomized to either SMP group or sPCNL group in a 1:1 ratio (50 in each group) using computer-generated simple randomization. Demographic data, stone characteristics, operative times, perioperative complications, blood transfusions, postoperative drop in haemoglobin, postoperative pain, duration of hospital stay and stone-free rates were compared between the two groups. RESULTS: Mean stone volume (2.41 cm2 vs 2.61 cm2) and stone-free rates (98% vs 94%, p = 0.14) were similar in both the SMP and sPCNL groups, respectively. The SMP group had significantly longer mean operative times (51.62 ± 10.17 min vs 35.6 ± 6.8 min, p = 0.03). Intraoperative calyceal injury (1/50 vs 7/50, p = 0.42) and mean postoperative drop in haemoglobin (0.8 ± 0.7 g/dl vs 1.2 ± 0.81, p = 0.21) were lower in the SMP group, but not statistically significant. SMP group showed significantly lower mean postoperative pain VAS scores (5.4 ± 0.7 vs 5.9 ± 0.9, p = 0.03) and mean duration of hospital stay (28.38 ± 3.6 h vs 39.84 ± 3.7 h, p = 0.0001). Complications up to Clavien grade 2 were comparable, with grade ≥ 3 complications higher in the standard group, but not statistically significant. CONCLUSION: Super-mini PCNL is equally effective as standard PCNL in treating renal calculi up to 3 cm, with significantly reduced postoperative pain and duration of hospital stay and lower risk of Clavien grade ≥ 3 complications, although with higher operative times.

Comparative analysis of combined spinal-epidural anesthesia and general anesthesia in percutaneous nephrolithotomy: a prospective study on surgical team and operating room personnel satisfaction.

OBJECTIVE: We aimed to investigate the efficacy and complications of combined spinalepidural anesthesia and general anesthesia in percutaneous stone surgery prospectively. MATERIALS AND METHODS: The study prospectively included patients who underwent percutaneous nephrolithotomy with general anesthesia (Group.1) or combined spinal-epidural anesthesia (Group.2) at the Department of Urology, Training and Research Hospital, Karabuk University. between December 2018 and December 2019. The effect of the anesthesia technique on the comfort and satisfaction of the operating room personnel, surgeon and anesthesia team were prospectively evaluated and recorded. RESULTS: During the postoperative period, the spinal anesthesia group had a significantly lower visual analog score than the general anesthesia group. No patient in either group required narcotic analgesics during the postoperative period. In terms of overall satisfaction scores, the surgeon performing the surgical procedure had a significantly higher satisfaction score in the general anesthesia group than in the CSEA group. The score was considered good in the general anesthesia group and moderate in the CSEA group. Personnel satisfaction was higher in the patient group that underwent CSEA. In the general anesthesia group, the score was considered to be average. In the CSEA group, the satisfaction score was considered good, with a statistically significant difference (p < 0.05). The anesthesia team's satisfaction score was moderate, with no significant difference between the CSEA and general anesthesia groups (p > 0.05). CONCLUSION: PCNL under CSEA can be performed safely in certain individuals. Different anesthetic techniques may have varied levels of satisfaction among the surgical team.

Vacuum-assisted mini-percutaneous nephrolithotomy is associated with lower rates of infectious complications compared to vacuum-cleaner procedure in patients at high risk for infections: a single-center experience.

PURPOSE: To evaluate the impact of vacuum-assisted mini-percutaneous nephrolithotomy (vamPCNL) vs. vacuum-cleaner mPCNL (vcmPCNL) on the rate of postoperative infectious complications in a cohort of patients with high risk factors for infections. METHODS: We retrospectively analysed data from 145 patients who underwent mPCNL between 01/2016 and 12/2022. Patient's demographics, stones characteristics and operative data were collected. vamPCNL and vcmPCNL were performed based on the surgeon's preference. High-risk patients were defied as having ≥ 2 predisposing factors for infections such as a history of previous urinary tract infections, positive urine culture before surgery, stone diameter ≥ 3 cm, diabetes mellitus and hydronephrosis. Complications were graded according to modified Clavien classification. Descriptive statistics and logistic regression models were used to identify factors associated with postoperative infectious complications. RESULTS: vamPCNL and vcmPCNL were performed in 94 (64.8%) and 51 (35.2%) cases, respectively. After surgery, infectious complications occurred in 43 (29.7%) participants. Patients who developed infectious complications had larger stone volume (p = 0.02) and higher rate of multiple stones (p = 0.01) than those who did not. Infectious complications occurred more frequently after vcmPCNL than vamPCNL (55.9% vs. 44.1%. p = 0.01) in high-risk patients. Longer operative time (p < 0.01) and length of stay (p < 0.01) were observed in cases with infectious complications. At multivariable logistic regression analysis, longer operative time (OR 1.1, p = 0.02) and vcmPCNL (OR 3.1, p = 0.03) procedures were independently associated with the risk of infectious complications post mPCNL, after accounting for stone volume. CONCLUSION: One out of three high-risk patients showed infectious complications after mPCNL. vamPCL and shorter operative time were independent protective factors for infections after surgery.

Transient ureteral obstruction after mini-percutaneous nephrolithotomy is associated with stone volume and location: results from a single-center, real-life study.

PURPOSE: To evaluate the rate of and predictors of ureteral obstruction after mini-percutaneous nephrolithotomy (mPCNL) for kidney stones. METHODS: We analyzed data from 263 consecutive patients who underwent mPCNL at a single tertiary referral academic between 01/2016 and 11/2022. Patient's demographics, stone characteristics, and operative data were collected. A nephrostomy tube was placed as the only exit strategy in each procedure. On postoperative day 2, an antegrade pyelography was performed to assess ureteral canalization. The nephrostomy tube was removed if ureteral canalization was successful. Descriptive statistics and logistic regression models were used to identify factors associated with a lack of ureteral canalization. RESULTS: Overall, median (IQR) age and stone volume were 56 (47-65) years and 1.7 (0.8-4.2) cm3, respectively. Of 263, 55 (20.9%) patients showed ureteral obstruction during pyelography. Patients without ureteral canalization had larger stone volume (p < 0.001), longer operative time (p < 0.01), and higher rate of stones in the renal pelvis (p < 0.01) than those with normal pyelography. Length of stay was longer (p < 0.01), and postoperative complications (p = 0.03) were more frequent in patients without ureteral canalization. Multivariable logistic regression analysis revealed that stone volume (OR 1.1, p = 0.02) and stone located in the renal pelvis (OR 2.2, p = 0.04) were independent predictors of transient ureteral obstruction, after accounting for operative time. CONCLUSION: One out of five patients showed transient ureteral obstruction after mPCNL. Patients with a higher stone burden and with stones in the renal pelvis are at higher risk of inadequate ureteral canalization. Internal drainage might be considered in these cases to avoid potential complications.

Radiation exposure of patients during endourological procedures.

PURPOSE: Considering the existing gaps in the literature regarding patient radiation dose (RD) and its associated risks, a systematic review of the literature on RD was conducted, focusing on percutaneous nephrolithotomy (PCNL), extracorporeal shock wave lithotripsy (SWL), and ureteroscopy (URS). METHODS: Two authors conducted a literature search on PubMed, Web of Science, and Google Scholar to identify studies on RD during endourological procedures. Two thousand two hundred sixty-six articles were screened. Sixty-five publications met the inclusion criteria using the PRISMA standards. RESULTS: RD was generally highest for PCNL, reaching levels up to 33 mSv, 28,700 mGycm2, and 430.8 mGy. This was followed by SWL, with RD reaching up to 7.32 mSv, 13,082 mGycm2, and 142 mGy. URS demonstrated lower RD, reaching up to 6.07 mSv, 8920 mGycm2, and 46.99 mGy. Surgeon experience and case load were inversely associated with RD. Strategies such as optimizing fluoroscopy settings, implementing ultrasound (US), and following the ALARA (As Low As Reasonably Achievable) principle minimized RD. CONCLUSIONS: This is the first systematic review analyzing RD, which was generally highest during PCNL, followed by SWL and URS. There is no specific RD limit for these procedures. Implementation of strategies such as optimizing fluoroscopy settings, utilizing US, and adhering to the ALARA principle proved effective in reducing RD. However, further research is needed to explore the factors influencing RD, assess their impact on patient outcomes, and establish procedure-specific reference levels for RD.

Clinical study of UMP and RIRS in 1.0-2.0 cm diameter renal/upper ureteral calculi.

BACKGROUND: The purpose of this study was to compare the efficacy and safety of Ultra-mini-percutaneous nephrolithotomy (UMP) and Retrograde intrarenal surgery (RIRS) for renal/upper ureteral calculi in 1.0-2.0 cm diameter. METHODS: From October 2017 to October 2022, the surgical treatment of patients with renal/upper ureteral calculi in 1.0-2.0 cm diameter who were admitted to our hospital was retrospectively analyzed. They were divided into two groups, the UMP group (sixty-two cases) and the RIRS group (one hundred and nine cases), according to the different surgical methods. Baseline data includes general information, stone size, location, CT value, hydronephrosis, creatinine level, etc. RESULTS: Intraoperative blood loss was 33.6 ± 8.5 ml in the UMP group was significantly more than 4.3 ± 0.7 ml in the RIRS group (P < 0.05). Intraoperative renal pelvis pressure of UMP group 10.5 ± 1.3 mmHg was significantly lower than RIRS group 23.6 ± 5.6 mmHg (P < 0.05). The incidence of postoperative infection was higher in the RIRS group (thirteen cases [11.93%]), and one case ([1.61%]) in the UMP group (P < 0.05). Routine CT scans on the second day and two months after surgery showed that the stone clearance rates in the UMP group were 87.1% and 93.5%, respectively, higher than those in the RIRS group (69.7% and 79.8%, respectively; P < 0.05). CONCLUSION: UMP has the advantage of a higher stone-free rate but a higher risk of injury and bleeding. The advantages of RIRS include less trauma, less bleeding, and faster recovery, but lower stone-free rates and a higher risk of infection.

A retrospective comparison of Sun's tip-flexible semirigid ureterorenoscopy, super-mini percutaneous nephrolithotomy and flexible ureteroscopy applied to treat upper urinary tract calculi.

BACKGROUND: This retrospective study was conducted to compare the safety and efficacy of Sun's tip-flexible semirigid ureterorenoscopy (tf-URS), super-mini percutaneous nephrolithotomy (SMP) and flexible ureteroscopy (FURS) in treating upper urinary tract calculi, including upper ureteral or renal calculi. METHODS: We included patients with upper ureteral calculi or renal calculi 1.0-2.0 cm in size, who underwent tf-URS, SMP or FURS, respectively. The indicators reflecting safety and efficacy were compared among the three surgical techniques. RESULTS: SMP presented with higher single stone crushing success rate, but longer operation time and postoperative hospital stay, more blood loss, and higher postoperative pain score compared with FURS and tf-URS (P < 0.05). The hospitalization cost of tf-URS group was lower than that of SMP and FURS groups (P < 0.05). The incidence of postoperative fever in tf-URS group was significantly higher than that in SMP group (P < 0.05). No significant difference was found in mucosal injury, perirenal hematoma, and stone-free rate at 3 months after surgery (P > 0.05). CONCLUSIONS: tf-URS and FURS have the advantages in minimal invasion, hospitalization cost, patient comfort, and hospital stay while SMP has higher stone-free rate. These three surgical techniques are safe, reliable and complementary, which should be selected according to the actual situation.

Percutaneous nephrolithotomy guided by 5G-powered robot-assisted teleultrasound diagnosis system: first clinical experience with a novel tele-assistance approach (IDEAL stage 1).

BACKGROUND: To demonstrate the technical feasibility of percutaneous nephrolithotomy (PCNL) guided by 5G-powered robot-assisted teleultrasound diagnosis system (RTDS) in a complex kidney-stone (CKS) cohort and present our preliminary outcomes. PCNL is highly skill-required, which hinders it popularization in primary medical units of remote regions. We designed an innovative tele-assistance approach to make PCNL easy to be operated by inexperienced surgeons. METHODS: This was a prospective proof-of-concept study (IDEAL phase 1) on intraoperative tele-assistance provided by online urological experts via a 5G-powered RTDS. Total 15 CKS patients accepted this technology. Online experts manipulated a simulated probe to assist unskilled local operators by driving a patient-side robot-probe to guide and monitor the steps of access establishment and finding residual stones. RESULTS: Median total delay was 177ms despite one-way network-connecting distance > 5,800 km. No perceptible delay of audio-visual communication, driving robot-arm or dynamic ultrasound images was fed back. Successful tele-assistance was obtained in all cases. The first-puncture access-success rate was 78.6% with a one-session SF rate of 71.3% and without complications of grade III-V. CONCLUSIONS: The current technology based on 5G-powered RTDS can provide high-quality intraoperative tele-assistance, which has preliminarily shown satisfactory outcomes and reliable safety. It will break down a personal competence-based barrier to endow PCNL with more popular utilization. TRIAL REGISTRATION: The study was approved by ethics committee of the Xinjiang Kezhou People's Hospital and ethics committee of the First Affiliated Hospital of Nanjing Medical University and was registered on http://www.chictr.org.cn (ChiCTR2200065849, 16/11/2022).

Percutaneous nephrolithotomy or flexible ureteral lithotripsy, which one is better for patients with upper ureteral calculi of 1.5-2.0 cm in diameter.

PURPOSE: First research to evaluate the clinical efficacy and safety of flexible ureteral lithotripsy (FURSL) and percutaneous nephrolithotomy (PCNL) in the treatment of the upper ureteral stone is between 1.5 cm and 2.0 cm in diameter since there is no consensus with such ureteral stone yet. METHODS: From December 2018 to October 2022, 104 patients with calculi in the upper ureter received percutaneous nephrolithotomy (PCNL)or flexible ureteroscopic lithotripsy (FURSL) in our institution. The clinical data of the patients in the two groups were retrospectively searched. Stone removal rate, operation time, blood loss, postoperative pain score, postoperative inflammatory factor, postoperative complication rates and ureteral obstruction three months after the operation were compared between the two groups. RESULTS: A total of 104 patients were included in the study. The stone clearance rate and the secondary surgery rate were 88.89% and 7.41% in the FURSL group, the figures were 97.96% and 2.0% in the PCNL group (p = 0.067, 0.497). Regarding ureteral obstruction three months after the operation, there were 2 patients in FURSL group and 0 patients in PCNL group(p = 0.497).Compared to patients in FURSL group, patients in the PCNL group had shorter operation time(PCNL 71.81 ± 18.94 min vs. FURSL 86.80 ± 22.49 min, p = 0.0004), fewer complications(PCNL 20.37% vs. FURSL 6.12%), and lower postoperative inflammatory factor(p = 0.0004), yet they got more hemoglobin drop (PCNL 13.14 ± 9.81 g/L vs. FURSL 4.77 ± 3.55 g/L, p < 0.0001), higher postoperative pain scores(p = 0.0017) in the first three postoperative days and longer hospital stay (PCNL 4.96 ± 1.21 days vs. FURSL 3.60 ± 0.83 days). CONCLUSION: Both FURSL and PCNL were effective methods for treating upper ureteral stones of 1.5-2.0 cm in diameter given the extremely high stone clearance rate and a very low secondary surgery rate, as long as rare ureteral obstruction in medium-long term observation. Additionally, FURSL can effectively reduce surgical bleeding, postoperative pain, and hospital stay, while PCNL can decrease operation time, the risk of infection, and complications. Therefore, doctors could select suitable surgical treatment for those patients depending on their different clinical situations based on these findings.

Comparison of lithotripsy methods during mini-PNL: is there a role for ballistic lithotripsy in the era of high-power lasers.

BACKGROUND: For renal stones > 20 mm, percutaneous nephrolithotomy (PNL) offers the best stone clearance rates with acceptable complication rates. This study aimed to compare the efficiency of high-power holmium YAG laser and ballistic lithotripsy during mini-PNL. METHODS: Data from 880 patients who underwent mini-PNL for renal stones was investigated retrospectively. The study utilized propensity score matching to create two groups: laser lithotripsy (n = 440) and ballistic lithotripsy (n = 440). The groups were matched based on stone size, Guy's stone score, and stone density. The main objectives of the study were to assess the stone-free rate (SFR), duration of surgery, and complication rates. RESULTS: The average age of the population was 51.4 ± 7.1 years, with a mean stone size of 28.6 ± 8.3 mm and a mean stone density of 1205 ± 159 HU. There were no significant differences between the groups. The SFRs of the laser lithotripsy and ballistic lithotripsy were 92.5% and 90.2%, respectively (p = 0.23). The laser lithotripsy group had a notably shorter surgery time (40.1 ± 6.3 min) compared to the ballistic lithotripsy group (55.6 ± 9.9 min) (p = 0.03). Complication rates were similar (p = 0.67). CONCLUSIONS: Our study shows that a high-power holmium YAG laser provides quicker operation time compared to ballistic lithotripsy. However, ballistic lithotripsy is still an effective and safe option for stone fragmentation during mini-PNL. In places where a high-power holmium YAG laser is not available, ballistic lithotripters are still a safe, effective, and affordable option for mini-PNL.

Comparison of two methods for treatment of 1-2 cm kidney stones in pediatric patients: mini PCNL and RIRS.

OBJECTIVE: This study aimed to compare the results of retrograde intrarenal surgery (RIRS) and mini-percutaneous nephrolithotomy (mini-PCNL) for the treatment of 1-2 cm kidney stones in pediatric patients. METHODS: The records of patients under the age of 18 years who were diagnosed with unilateral 1-2 cm kidney stones for the first time and underwent endoscopic surgery between February 2008 and April 2022 were retrospectively examined. The patients were divided into two groups: mini-PCNL and RIRS surgery. Parameters such as age, gender, number of stones, side, size and localization were examined. The main endpoint of the study was to compare stone-free rates (SFR) one month after both surgeries. Surgery and fluoroscopy times, postoperative hospital stay, hemoglobin decrease and complication rates were compared between the groups. SFR was evaluated one month after surgery by direct urinary system radiography and USG or CT. RESULTS: A total of 58 patients were included in the study. There were 35 patients in the mini-PCNL group and 23 patients in the RIRS group. Table 1 shows the demographic and clinical characteristics of both groups. There was no significant difference between the groups in terms of age, gender, stone size, location, side and density. Calcium oxalate stones were observed at a higher rate in both groups. Mean fluoroscopy time was higher in the mini-PCNL group (p = 0.001). The mean surgery time was lower in the mini-PCNL group (p = 0.024). The mean hemoglobin decrease was greater in the percutaneous group (p = 0.039). There were no differences between the groups in terms of postoperative hospital stay, complication rates, and SFR one month after surgery. CONCLUSION: Although mini-PCNL seems to be more advantageous in terms of operation time compared to RIRS, it is disadvantageous in terms of average fluoroscopy time, radiation received and average hemoglobin decrease.

Feasibility of Simultaneous Bilateral Endoscopic Surgery in Prone Split-Leg Position for Bilateral Upper Urinary Tract Calculi: A Pilot Study.

INTRODUCTION: We explored the viability of simultaneous bilateral endoscopic surgery (SBES) in the prone split-leg position for managing bilateral calculi. METHODS: We retrospectively reviewed 72 patients who underwent SBES, with procedures involving ureteroscopy (URS) and contralateral percutaneous nephrolithotomy (PNL) simultaneously, in prone split-leg position. RESULTS: Operative times averaged 109.38 ± 30.76 min, with an average hospital stay of 7.79 ± 3.78 days. The bilateral stone-free rate (SFR) was 70.83%, while URS and PNL demonstrated comparable unilateral SFR (83.33% and 79.17%, respectively). Receiver operating characteristics curves for predicting unilateral residual fragments yielded an area under the curve of 0.84 (URS) and 0.81 (PNL) with respective cutoff values of stone diameter of 11.55 mm and 23.52 mm. Fifty-seven (79.17%) and 15 (20.83%) patients encountered grade 0-1/2 complications, with no severe complications (grade 3-5) recorded. No significant changes in blood count or renal function were observed post-SBES. CONCLUSIONS: SBES in the prone split-leg position is a viable option for managing bilateral upper tract urolithiasis. Larger scale studies are needed to further assess safety and efficacy in various positions.

Experimental study of a new technique for minimally invasive percutaneous nephrolithotomy: intelligent pressure-controlled minimally invasive percutaneous nephrolithotomy.

BACKGROUND: To test the reliability and safety of a newly invented technique for minimally invasive percutaneous nephrolithotomy, intelligent pressure-controlled minimally invasive percutaneous nephrolithotomy (IPC-MPCNL). METHODS: Eighteen kidneys of nine female pigs were randomly divided into three groups. Those in Groups A and B underwent IPC-MPCNL through the new system composed of a pressure-measuring MPCNL suctioning sheath and an irrigation and suctioning platform with pressure feedback control. The infusion flow rate was 500 ml/min in Group A and 750 ml/min in Group B. Those in Group C underwent MPCNL at an infusion flow rate of 500 ml/min. The renal pelvic pressure (RPP) monitored by a ureteral catheter and that monitored by the pressure-measuring sheath in Groups A and B were compared. The RPP in Group C was monitored by a ureteral catheter. RESULTS: The RPP measured by the pressure-measuring sheath and that measured by the ureteral catheter in Group A was - 5.59 ± 1.95 mmHg and 4.46 ± 2.08 mmHg, respectively. The RPP measured by the pressure-measuring sheath and that measured by the ureteral catheter in Group B was - 4.00 ± 2.01 mmHg and 5.92 ± 2.05 mmHg, respectively. Hence, the RPPs measured by the pressure-measuring sheath in Groups A and B were consistent with those measured by the ureteral catheter. The RPP in Group C was 27.75 ± 5.98 mmHg (large fluctuations). CONCLUSIONS: IPC-MPCNL can be used to accurately monitor the RPP and maintain it within a preset safe range via suction. The new technique and the new system are safe and reliable.

Comparing Balloon Dilation to Non-Balloon Dilation for Access in Ultrasound-Guided Percutaneous Nephrolithotomy: A Systematic Review and Meta-Analysis.

PURPOSE: This study aims to evaluate the safety and efficacy of ultrasound-guided balloon dilation compared to non-balloon dilation for percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: A systematic review and meta-analysis were conducted by searching PubMed, EMBASE, and the Cochrane Library. Results were filtered using predefined inclusion and exclusion criteria as described and meta-analysis was performed using Review Manager 5.4 software. RESULTS: A total of six studies involving 1189 patients who underwent PCNL were included. The meta-analysis results demonstrated that compared to non-balloon dilation, balloon dilation was associated with reduced haemoglobin drop [mean difference (MD) = -0.26, 95% CI = -0.40 ~ -0.12, P = 0.0002], decreased transfusion rate [odds ratio (OR) = 0.47, 95% CI = 0.24 ~ 0.92, P = 0.03], shorter tract establishment time (MD = -1.30, 95% CI = -1.87 ~ -0.72, P < 0.0001) and shorter operation time (MD = -5.23, 95% CI = -10.19 ~ -0.27, P = 0.04). CONCLUSIONS: Overall, ultrasound-guided balloon dilatation offered several advantages in PCNL procedures. It facilitated faster access establishment, as evidenced by shorter access creation time. Additionally, it reduced the risk of kidney injury by minimizing postoperative haemoglobin drop and decreasing the need for transfusions. Moreover, it enhanced the efficiency of surgery by reducing the operation time. However, it is important to note that the quality of some included studies was subpar, as they did not adequately control for confounding factors that may affect the outcomes. Therefore, further research is necessary to validate and strengthen these findings.

Intraoperative computed tomography for detection of residual stones in endourology procedures: systematic review and meta-analysis.

BACKGROUND: Success rates in endourological procedures, notably percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS), have demonstrated suboptimal outcomes, leading to more reinterventions and radiation exposure. Recently, the use of intraoperative computed tomography (ICT) scans has been hypothesized as a promising solution for improving outcomes in endourology procedures. With this considered, we conducted a comprehensive systematic review and meta-analysis encompassing all available studies that evaluate the impact of the use of intraoperative CT scans on surgical outcomes compared to conventional fluoroscopic-guided procedures. METHODS: This systematic review was conducted in accordance with PRISMA guidelines. Multiple databases were systematically searched up to December of 2023. This study aimed to directly compare the use of an ICT scan with the standard non-ICT-guided procedure. The primary endpoint of interest was success rate, and the secondary endpoints were complications and reintervention rates, while radiation exposure was also evaluated. Data extraction and quality assessment were performed following Cochrane recommendations. Data was presented as an Odds ratio with 95%CI across trials and a random-effects model was selected for pooling of data. RESULTS: A comprehensive search yielded 533 studies, resulting in the selection of 3 cohorts including 327 patients (103 ICT vs 224 in non-ICT). Primary outcome was significantly higher in the experimental group versus the control group (84.5% vs 41.4% respectively, 307 patients; 95% CI [3.61, 12.72]; p<0.00001; I2=0). Reintervention rates also decreased from 32.6% in the control to 12.6% in the ICT group (OR 0.34; 95%CI [0.12,0.94]; p =0.04; I2= 48%), whereas complication rates did not exhibit significant differences. Radiation exposure was also significantly reduced in two of the included studies. CONCLUSION: This meta-analysis highlights a favorable outcome with intraoperative CT scan use in PCNL procedures, showing a considerable increase in SFR when compared to standard fluoroscopy and nephroscopy. Despite limited studies, our synthesis underscores the potential of ICT scans to significantly reduce residual stones and their consequences for endourology patients, as reinterventions and follow-up ionizing radiation studies.

Ureteroscopic lithotripsy with pressure-measuring ureteral access sheath for large ureteral stones.

INTRODUCTION: To evaluate the safety and efficacy of ureteroscopic lithotripsy with pressure-measuring ureteral access sheath (PM-UAS) for large ureteral stones. MATERIAL AND METHODS: A total of 258 consecutive patients with large ureteral stones ≥15 mm was enrolled. They were treated by ureteroscopic lithotripsy with PM-UAS in the oblique supine lithotomy position. The technology can precisely monitor and automatically control cavity pressure. The cavity pressure control value was set at -15 mmHg∼-5 mmHg. The cavity pressure limit value was set at 30 mmHg. Infusion flow rate was set at 100-200 ml/min. Postoperative data such as stone-free rate and complications were analyzed. RESULTS: PM-UAS was successfully implanted in 225 patients at one stage. Eighteen cases of patients who had failed the first surgery were successfully treated with a second operation. Fifty-one cases with stones migrating up to the kidney were converted to flexible lithotripsy. The other 15 cases were converted to percutaneous nephrolithotomy due to significant ureteral stenosis. The operative time was 49.5 ± 11.2 min. The stone-free rates after one month and three months were 87.2% (212/243) and 94.2% (229/243), respectively. Complications from grade I to II were observed in 25(10.3%) patients. No other complications from grade III to V were noted. CONCLUSION: The ureteroscopic lithotripsy with PM-UAS is safe and efficacious for large ureteral stones.

[Progress in Surgical Treatment of Upper Urinary Tract Stones in Children].

The incidence of urinary calculi in children has been increasing annually,and most of the cases are upper urinary tract stones.At present,surgery is the main way to treat upper urinary tract stones in children.With the gradual development of minimally invasive techniques in surgery,percutaneous nephrolithotomy,retrograde intrarenal surgery,and extracorporeal shock wave lithotripsy have become the main methods for treating upper urinary tract stones in children.We reviewed the current progress in surgical treatment of upper urinary tract stones in children and provided prospects for future treatment options.