Guy's Stone Research Articles

Intravenous Pyelogram (IVP)-Based Guy’s Stone Score (GSS) Utility for Prediction of Outcomes of Upper Pole Access Percutaneous Nephrolithotomy (PCNL)

Background: Renal stone disease is a very common disease, and its lifetime prevalence is 1 - 15%, with a gradual rise in incidence and disease prevalence. There are significant financial implications of its management. Nowadays, for big (typically > 2 cm) renal and upper ureteric stones, PCNL is widely regarded as the first-line treatment. Because most of the intrarenal collecting systems can be accessed by superior calyceal puncture in PCNL, good stone clearance can be achieved. The “Guy’s Stone Score” is a useful technique for categorizing the complexity of PCNL. Objectives: This study aimed to evaluate the role of Guys Stone Score based on KUB and intravenous urography to predict the success rate, grading, and complexity of PCNL, which are performed via the upper pole access. Methods: The present prospective, non-randomized observational study was undertaken in the Department of Urology and Renal transplantation, SCBMCH, Cuttack, from 1st November 2017 to 31st October 2019. A total of 104 patients were enrolled in the study in whom PCNL was performed through superior calyceal puncture, based on preoperative intravenous pyelogram. The Guy's Stone Score was calculated, and the complexity of the procedure was graded using radiological studies, then the outcome was determined accordingly. Results: In this study, 59.6% of the patients had immediate success among them 29.0% had grade 3, and 6.5% had grade 4 GSS. Moreover, 38.4% of the patients had clinically significant residual fragments among them, 75.0% had grade 4, and 20.0% had grade 3 GSS.23% of the patients underwent REDO-PCNL and 11.5% of the patients underwent accesory/ancillary procedure of ESWL. Conclusions: The present study shows that an intravenous pyelogram-based Guy’s Stone Score (GSS) is an easy-to-use tool in predicting the early success rate and potential difficulties and complications in PCNL performed through superior calyceal puncture.

Comparative study between Guy's stone score, S.T.O.N.E nephrolithometry and Clinical Research Office of the Endourological Society (CROES) nephrolithometric nomogram in predicting stone-free rates in patients undergoing percutaneous nephrolithotomy: A prospective analysis

Comparative study between Guy's stone score, S.T.O.N.E nephrolithometry and Clinical Research Office of the Endourological Society (CROES) nephrolithometric nomogram in predicting stone-free rates in patients undergoing percutaneous nephrolithotomy: A prospective analysis

Comparison of percutaneous nephrolithotomy and retrograde intrarenal surgery outcomes for kidney stones larger than 2cm from Guy's stone scoring system perspective.

To compare surgical outcomes of percutaneous nephrolithotomy (PNL) and retrograde intrarenal surgeries (RIRS) as a result of kidney stones larger than 2cm, together with Guy's stone scores (GSS). The data of 811 patients with stone sizes 2-6cm were operated using PNL (n=361) and RIRS (n=450) reviewed retrospectively. GSS were graded 1, 2, 3 or 4 according to the computed tomography findings. Stone-free rate (SFR), operation times, length of hospital stay (LOHS) and Clavien complications (CC) were recorded. Although mean operative times were significantly longer in the RIRS group than the PNL group in GSS grades 1, 2 and 3 (P<.001), it was similar between the two groups in GSS grade 4 (P=.186). SFRs in the PNL and RIRS group were 90.3% and 58.4% on post-operative 10th day (P<.001), and it raised up to 95.3% and 81.6% after secondary interventions (P<.001). Significantly higher SFRs observed in the PNL group in GSS grades 1, 2 and 3 categories. On postoperative 10th day, the SFRs were similar in both GSS grade 4 categories (P=.06). LOHS was longer in the PNL group (P<.001). Although LOHS was significantly longer only in GSS grade 3 (P=.043) and GSS grade 4 (P<.001) in the PNL group, it was similar in GSS grade 1 and 2 between groups. Clavien complications increased in line with GSS in the PNL group (P<.001), but the difference did not differ between GSS grade 3 and 4. SF of PNL in a single session and short operation time seems to be significant especially in GSS grades 1, 2 and 3 category stones. Although the number of patients in the GSS 4 group is very small to claim this, RIRS might be considered as an alternative to PNL in a special group of patients such as GSS grade 4 because of its lower complication rates and shorter LOHS.

Guy’s Stone Score: A Predictive Tool for Outcomes of Percutaneous Nephrolithotomy

Background: Predicting stone clearance before intervention can be useful to plan the modality of treatment and calculate the cost of procedures. Therefore, this study aims to determine the frequency of successful stone clearance in a patient undergoing percutaneous nephrolithotomy (PCNL) with different categories of Guy's Stone Score (GSS).&#x0D; Methodology: A total of 115 patients undergoing standard PCNL from January to December 2018 were included in this study. According to GSS I-IV, patients were then categorized into four groups after having pre-operative Computed Tomography of Kidney, Ureter, and Bladder (KUB). All the patients received standard general anesthesia and underwent standard PCNL in a prone position. The Percutaneous nephrostomy 18-gauge needle is passed into the pelvis of the kidney, Pelvi-calyceal system opacified and confirmed using fluoroscopy, a guidewire is passed, and 30 Fr Amplatz sheath is introduced after serial dilatation. A 26 Fr nephroscope is then inserted through the working sheath, and the stone is fragmented and removed. Finally, a nephrostomy drain tube is kept at the puncture site. The outcome was accessed in terms of stone clearance rate after PCNL on the 2nd postoperative day using the radiological modality of CT-KUB.&#x0D; Results: Among the 115 patients here were 48(41.7%) categorized as GSS I, 26(22.6%) categorized as GSSII, 20(17.4%) categorized as GSS III, and 21(18.3%) categorized as GSS IV. The overall stone clearance observed was 64.3%, individual stone clearance was GSS I=91.66%, GSS II=53.84%, GSS III=50%, and GSS IV=28.57%. Stone clearance among the different GSS categories was significantly different (p&lt;0.01).&#x0D; Conclusion: The Guy's Stone Score, based on CT scan findings, is a significant system in predicting successful stone-free rates. It is a convenient, quick, and efficient tool for pre-operative assessment, and it can be incorporated as a mandatory protocol before planning PCNL.

Peri-Operative Predictors of Postoperative Bleeding and Sepsis after Percutaneous Nephrolithotomy

Introduction: Percutaneous nephrolithotomy (PCNL) is the most common minimal access method used for the management of large renal and pelvic stones. The two most common complications after PCNL are bleeding and sepsis. In this context, we did this study to find out perioperative predictors of postoperative bleeding and sepsis after PCNL. Materials and Methods: We conducted this study on 110 patients who came for PCNL at our institute from March 1, 2018 to August 31, 2019. Data were collected using a pro forma, and the same analyzed by appropriate statistical methods using the SPSS software. Results: The perioperative factors correlated to postoperative bleeding were stone size, density of stone, Guy's stone score, size of Amplatz sheath used, number of working tracts created, and duration of surgery. On regression analysis factors which were predictive of postoperative bleeding were size of Amplatz sheath and number of working tracts created. Peri-operative factors correlated with postoperative sepsis were body mass index of the patient, preoperative total count, density of stone, preoperative pyuria, preoperative positive urine culture, superior calyceal puncture, postoperative total leukocyte count, and postoperative fever within 24 h. The factors which were predictive of postoperative sepsis were preoperative pyuria, preoperative urine culture, superior calyceal puncture, and postoperative fever on regression analysis. Conclusion: This study shows perioperative predictors of postoperative bleeding and sepsis after PCNL. Out of 43.63% total complications, 20% were major and 23.63% minor complications.

Tranexamic acid in patients with complex stones undergoing percutaneous nephrolithotomy: a randomised, double-blinded, placebo-controlled trial.

To assess the efficacy and safety of single-dose tranexamic acid on the blood transfusion rate and outcomes of patients with complex kidney stones undergoing percutaneous nephrolithotomy (PCNL). In a randomised, double-blinded, placebo-controlled trial, 192 patients with complex kidney stone (Guy's Stone Scores III-IV) were prospectively enrolled and randomised (1:1 ratio) to receive either one dose of tranexamic acid (1 g) or a placebo at the time of anaesthetic induction for PCNL. The primary outcome measure was the occurrence rate of perioperative blood transfusion. The secondary outcome measures included blood loss, operative time, stone-free rate (SFR), and complications. ClinicalTrials.gov identifier: NCT02966236. The overall risk of receiving a blood transfusion was reduced in the tranexamic acid group (2.2% vs 10.4%; relative risk, 0.21, 95% confidence interval [CI] 0.03-0.76, P = 0.033; number-needed-to-treat: 12). Patients randomised to the tranexamic acid group had a higher immediate and 3-month SFR compared with those in the placebo group (29% vs 14.7%, odds ratio [OR] 2.37, 95% CI 1.15-4.87, P = 0.019, and 46.2% vs 28.1%, OR 2.20, 95% CI 1.20-4.02, P = 0.011, respectively). Faster haemoglobin recovery occurred in patients in the tranexamic acid group (mean, 21.3 days; P = 0.001). No statistical differences were found in operative time and complications between groups. Tranexamic acid administration is safe and reduces the need for blood transfusion by five-times in patients with complex kidney stones undergoing PCNL. Moreover, tranexamic acid may contribute to better stone clearance rate and faster haemoglobin recovery without increasing complications. A single dose of tranexamic acid at the time of anaesthetic induction could be considered standard clinical practice for patients with complex kidney stones undergoing PCNL.

Introducing trifecta for percutaneous nephrolithotomies: a proposal for standard reporting outcomes after treatment for renal stones.

In literature, the reports of outcomes after percutaneous nephrolithotomies are rather heterogeneous. This may influence studies comparison, it may also render difficult to evaluate surgical adequacy, perioperative morbidity, and patient's Quality of Life between studies. For this reason, we propose to introduce PNL-Trifecta as composite measure to standardize data reporting outcomes after percutaneous nephrolithotomies. We performed a prospective multicentric study on consecutive patients undergone PNL to treat renal stones between 2018 and 2020. Successful PNL-trifecta was considered achieved when procedures obtained the three following results: no residual fragments >2 mm at unenhanced CT scan at 3 months postop, no complications (defined as Clavien-Dindo Score 0) and operation carried out without placing a nephrostomy tube (tubeless or totally tubeless). We compared results of standard versus mini-PNL and between stones of different complexity (evaluated with Guy's Stone Score and S.T.O.N.E. Nephrolithometry Score). Univariate analysis was utilized to identify other factors influencing achievement of PNL-Trifecta. Two hundred forty-five patients fulfilled inclusion/exclusion criteria and have been enrolled in the study (median age: 56, IQR 48-57). The overall PNL-Trifecta achievement rate was 22.85% (28.66% in the mini-PNL group and 13.68% in the standard-PNL group, P=0.010). The stone free rate, CD 0 rate and tubeless/totally tubeless rate in the mini-PNL group were 60.66%, 89.33% and 51.33% respectively. In the standard-PNL group they were 44.21%, 40.00% and 15.78% respectively. At the univariate analysis, differences between Guy's Stone Score groups in achieving PNL-Trifecta were significant (P=0.001). Also, the level of upper puncture (P=0.010) and utilization of device with active suction (P=0.002) showed statistically significant differences. Furthermore, the length of stay in the patient's group achieving Trifecta was 2.28 versus a mean length of stay of 4.64 days in the group of patients not achieving Trifecta (P=0.046). We present Trifecta for PNLs as a potential tool to evaluate quality of percutaneous nephrolithotomies and to provide an instrument for an adequate standard data reporting. It can represent a valid way to assess and monitor surgeon's learning curves. It will require further external validation and studies to evaluate its correlation with mid- and long-term results and patient's health related Quality of Life outcomes.

COMPARISON OF S.T.O.N.E. SCORE AND GUY SCORE IN PREDICTING STONE FREE RATES OF PERCUTANEOUS NEPHROLITHOTOMY PROCEDURES IN THE SOETOMO GENERAL HOSPITAL

Objective: To determine the effectiveness of Modified Guy's Stone Score (GSS) and S.T.O.N.E score (SS) as predictors of stone free rates in patients undergoing PCNL. Material &amp; Methods: The design of this study was a prospective observational analytic. Samples were patients with kidney stones who came to the Urology Polyclinic of Soetomo0 General Hospital Surabaya, which was planned to undergo PCNL surgery, patients who met the inclusion criteria will have a CT stonographic examination then counted for the S.T.O.N.E score and Modified Guy's Stone Score before the PCNL procedure. Postoperative stone size evaluation used KUB X-ray (BOF) to assess Stone Free Rate (SFR). Results: In the ETA statistical test there was a strong relationship between GSS and SFR with a relationship strength value of 0.609, the direction of the relationship between these two variables was positive. This means that the greater the GSS, the less likely the SFR could be achieved. The relationship between these two variables was significant with p= 0.05. While between SS and SFR with a relationship strength value of 0.55, the strength of the relationship in these two variables was positive which indicated the higher the SS, the less likely the occurrence of SFR. But both of them were not statistically significant with p= 0.228. Conclusion: Guy Stone Score (GSS) gives a better predictive value than the STONE score (SS) on the stone free rates in patients undergoing PCNL procedures.

Perioperative Indices Predicting Fever Following Percutaneus Nephrolithotomy.

To investigate 18 independent peroperative parameters that may have an effect on fever after percutaneous nephrolithotomy (PCNL). A descriptive study. Departments of Urology, Nevşehir State Hospital, and Sultan Abdulhamid Han Education and Research Hospital, Turkey, from January 2016 to June 2019. Two hundred and seventy-six patients, who underwent PCNL between 2016 and 2019 in two institutions, were evaluated retrospectively. Patients were divided as Group I and II, according to the absence or presence of fever after PCNL, then peroperative parameters were compared. There was no statistically significant difference between Group I and II in terms of age, gender, side of stone, ipsilateral open stone surgery or PCNL history, presence of renal anatomic anomaly, preoperative hydronephrosis grade, stone size in computed tomography (CT), stone Houndsfield Unit (HU) value, skin stone distance, duration of operation, postoperative D-J insertion rate and postoperative blood transfusion requirement (p >0.05). Guy' s Stone Score (GSS), number of calyceal access and duration of achieving limpid urine coming out of the nephrostomy tube were significantly higher in Group II (p <0.05). The rate of postoperative fever was statistically significantly higher in patients with middle calyceal (mid-calyceal) access, than patients with inferior calyceal access (p=0.05). High GSS, mid-calyceal access, the increase in the amount of mid-calyceal access, the longer duration of achieving limpid urine coming out of the nephrostomy tube were found to be related with fever after PCNL. Key Words: PCNL, Post-PCNL fever, Nephrolithiasis, Guy's stone score.

Percutaneous nephrolithotomy in previously operated patients: A prospective study

Purpose:To determine the effect of previous renal stone surgery on result and complications of percutaneous nephrolithotomy (PCNL).Materials and Methods:Total 300 patients were enrolled in the study. We enrolled 100 surgery-naive cases (those with no history of any renal surgery) as control and labeled them as Group A. Group B comprised 100 cases who had PCNL in the past. Group C constituted 100 patients who had open renal stone surgery in the past. Stones were classified using Guy's stone score. PCNL was performed by standard technique in prone position and technical features encountered during operation and outcomes were compared between groups. Complications were graded using modified Clavien grading system.Results:There were no differences between the three groups in age, gender, body mass index, stone burden, and stone opacity. Multiple calyceal stones and distorted pelvicalyceal system anatomy were more in Group C, but stone score showed no statistically significant difference from other groups. The mean operative time (68.91 ± 21.27 min) and fluoroscopy time (264.40 ± 74.90 s) were longer in Group C, but there was no statistically significant difference between the groups. Multiple access was significantly more common in Group C compared to the other two groups (P < 0.001). Access location too did not show any statistically significant difference between the groups. Postoperative complications were more in previous stone surgery patients, but did not show statistically significant difference.Conclusion:PCNL is a safe and effective treatment modality for patients with renal stones regardless of history of previous PCNL or open renal surgery.

Percutaneous nephrolithotomy in patients with spinal cord injury: should all these patients be automatically assigned a Guy's stone score of 4?

To assess the complication and stone-free rates of PCNL in patients with spinal cord injury (SCI) and to evaluate whether this population should be assigned a Guy's stone score (GSS) of 4. A case-control study was conducted, and electronic charts were reviewed to search for patients with SCI, bladder dysfunction, and kidney stones who had undergone PCNL. Control cases were randomly selected from among patients with complete staghorn calculus (GSS = 4). One hundred and seventeen patients were included. Patients with SCI had a significant shorter operative time (119 vs. 141min; p = 0.018). There were no significant differences between the groups in terms of the patients' position, number of renal tracts, bleeding or transfusion rate; however, there was a significantly higher complication rate (23.1% vs. 7.8%; p = 0.009) and a longer hospital stay (5.8 vs. 3.1days; p = 0.002) among patients with SCI. With regards to the stone-free rate in patients with different grades of GSS patients with SCI who had a GSS of 1 had a stone-free rate of 85.7%, while those with a GSS of 2, 3, or 4 had 50%, 50%, and 31.5%, respectively (p = 0.024). Only patients with a GSS of 4 in the SCI group had outcomes that were similar to those of control patients (31.5% vs. 31.6%). Patients with SCI should not be automatically assigned GSS 4. Stone-free rate is related to stone burden in these patients, although they do show a higher complication rate and a longer hospital stay than non-neurological patients.

Percutaneous Nephrolithotomy in Paediatric Population: A Single Center Experience.

Management of paediatric stone disease is challenging as they are considered high risk group. Percutaneous nephrolithotomy is minimally invasive procedure with definite advantages in terms of higher stone clearance in single session and no long term effect in renal function. Retrospective study was done including all patients upto the age of 18 years who underwent Percutaneous nephrolithotomy from January 2010 to December 2018 in our center after taking approval from ethical committee. Data was collected regarding gender, operative side, operative time duration, hospital stay, post-operative decrease in hemoglobin, stone size, Guy's stone score and early post-operative complications with Clavien-Dindo grade. Percutaneous nephrolithotomy was done in 48 renal units in 44 patients. 28 patients were boys and 16 were girls with mean age of 10.91 ± 5.22 years and mean stone size 17.16 ± 6.43 mm. 91.6% of cases had Guy's stone score of 1 and 2. Standard percutaneous nephrolithotomy was done in 21 renal units, mini percutaneous nephrolithotomy in 24 renal units and supermini percutaneous nephrolithotomy was done in three renal units with total stone free rate of 93.4%. Three patients required extracorporeal shockwave lithotripsy for significant residual stone. Average post-operative hemoglobin drop was 1.2 gm%. Overall complications rate was 18.1% with 4.5% of complications being grade 1 and 2 whereas 13.6% were Grade 3. Percutaneous nephrolithotomy is safe and feasible in paediatric patients with large stone burden, complex anatomy or shock-wave lithotripsy failure with acceptable complication and stone free rate.

Evaluation of Nephrolithometric Scoring Systems to Predict Outcomes of Retrograde Intrarenal Surgery.

The aim of the study was to evaluate the predictive value of nephrolithometric scoring systems used to predict the complexity of renal stones for the outcomes of retrograde intrarenal surgery (RIRS). A total of 81 patients who underwent RIRS for nephrolithiasis between January 2013 and October 2017 were reviewed in this retrospective study. Guy's Stone Score (GSS), the S.T.O.N.E., Clinical Research Office of the Endourologic Society (CROES), and Seoul National University Renal Stone Complexity (S-ReSC) nephrolithometry scores were assessed by same researcher for each patient from preoperative non-contrast enhanced computed tomography scans. These nephrolithometric scores, stone characteristics and complications were compared in patients with/without residual stone. The median (IQR) age of patients (37 female/44 male) was 45 (20) years. The median (IQR) stone burden was 139.4 (125.4) mm2 and the mean Hounsfield unit (HU) value was 1034.46 ± 239.56. The stone burden, S.T.O.N.E. and S-ReSC scores were statistically significantly higher and the CROES score was significantly lower in patients with a residual stone (p < 0.001, for all). The incidence of residual stones was statistically significantly higher in patients with Grade 3 GSS (p = 0.018). While S.T.O.N.E., S-ReSC and CROES were significantly correlated with stone-free rates, GSS failed to correlate with stone-free status. According to the receiver operating characteristic (ROC) curve analysis, the predictive value of stone burden was higher for residual stones, compared to S-ReSC scoring (p < 0.05). Nephrolithometric scoring systems nomograms used to predict the PCNL success were not superior to stone burden in predicting the RIRS success.

Critical Application of Adult Nephrolithometric Scoring Systems to Children Undergoing Mini-Percutaneous Nephrolithotomy.

Objective: To evaluate and compare the ability of the Guy's stone score (GSS), the S.T.O.N.E. nephrolithometry, and the Clinical Research Office of the Endourology Society (CROES) nomogram to predict the outcome of mini-percutaneous nephrolithotomy (MPNL) in children, and to identify which of the predictors involved in these scoring systems can separately affect this outcome. Patients and Methods: All children younger than 14 years who had MPNL in our center over a period of 3 years were included prospectively. Bivariate analyses were done to evaluate the associations of the three scoring systems and the predictors composing them with single-session stone clearance and complications. Receiver operating characteristic (ROC) curve analyses of the three scoring systems were conducted to evaluate and compare their abilities to predict the outcomes. Decision curve analyses for the three scoring systems were conducted to evaluate the clinical benefit of using each of them to predict stone clearance. Results: We consecutively enrolled 92 renal units in 89 children with a median age of 9.5 years. Single-session stone clearance was achieved in 76 (82.6%) renal units. Complications occurred with 19 (20.7%) procedures. Stone multiplicity (p = 0.043), staghorn stone (p = 0.007), prior stone treatment (p < 0.001), number of calices involved (p = 0.006), stone burden (p = 0.003), GSS (p < 0.001), S.T.O.N.E. nephrolithometry (p = 0.012), and CROES nomogram (p < 0.001) had significant associations with stone clearance. Only stone attenuation was significantly associated with complications (p = 0.031). For prediction of stone clearance, CROES nomogram demonstrated the greatest area under the ROC curve and the greatest net benefit on decision curve analyses. Conclusions: For children undergoing MPNL, CROES nomogram is the best to predict stone clearance. However, none of the studied scoring systems predicted complications efficiently.

Predicting the Postoperative Outcome of Percutaneous Nephrolithotomy with Machine Learning System: Software Validation and Comparative Analysis with Guy's Stone Score and the CROES Nomogram.

Purpose: To validate the output of a machine learning-based software as an intelligible interface for predicting multiple outcomes after percutaneous nephrolithotomy (PCNL). We compared the performance of this system with Guy's stone score (GSS) and the Clinical Research Office of Endourological Society (CROES) nomogram. Patients and Methods: Data from 146 adult patients (87 males, 59%) who underwent PCNL at our institute were used. To validate the system, accuracy of the software for predicting each postoperative outcome was compared with the actual outcome. Similarly, preoperative data were analyzed with GSS and CROES nomograms to determine stone-free status as predicted by these nomograms. A receiver operating characteristic (ROC) curve was generated for each scoring system, and the area under the ROC curve (AUC) was calculated and used to assess the predictive performance of all three models. Results: Overall stone-free rate was 72.6% (106/146). Forty of 146 patients (27.4%) were scheduled for 42 ancillary procedures (extracorporeal shockwave lithotripsy [SWL] [n = 31] or repeat PCNL [n = 11]) to manage residual renal stones. Overall, the machine learning system predicted the PCNL outcomes with an accuracy ranging between 80% and 95.1%. For predicting the stone-free status, the AUC for the software (0.915) was significantly larger than the AUC for GSS (0.615) or CROES nomograms (0.621) (p < 0.001). Conclusion: At the internal institutional level, the machine learning-based software was a promising tool for recording, processing, and predicting outcomes after PCNL. Validation of this system against an external dataset is highly recommended before its widespread application.

The Efficacy of Guy's Stone Score for Predicting the Stone-Free and Complication Rates in Children Treated by Percutaneous Nephrolithotomy.

Introduction: To determine the efficacy of Guy's stone score (GSS) for predicting stone-free and complication rates after percutaneous nephrolithotomy (PCNL) in children. Patients and Methods: A total of 197 renal units (RUs) in 173 children (≤17 years) who referred to our clinic were included in our study. RUs with stones were classified as four groups according to GSS. The results were designated as stone free or as having residual stones. Complications were evaluated according to GSS, the Satava, and modified Clavien grading system. All parameters were evaluated by using univariate and multivariate analysis. Results: The median age of patients was 6 years (1-17 years). Stone-free status was 77% and complication rate was 17%. Stone-free rate was established 89% for group 1, 78% for group 2, 75% for group 3, and 57% for group 4. There was a positive association between GSS and stone-free status (p = 0.02). No relationship was found between GSS and the complication rate (p = 0.42). In multivariate analysis, GSS was the only independent factor for predicting stone-free status. Conclusion: Current study revealed that GSS has a predictive ability for stone-free status; however, GSS is insufficient for predicting complications after pediatric PCNL. Even though, GSS does not fully reflect the characteristics of the pediatric population, we believe that it might provide useful insights for clinicians when recommending and discussing treatment options for children with urolithiasis.

What is the optimum lithotripsy method for high density stones during mini-PNL? Laser, ballistic or combination of both.

Percutaneous nephrolithotomy (PNL) is the primary treatment option for renal stones > 20mm in diameter. Mini-PNL gained popularity with its minimally invasive nature. The aim of this study was to compare the efficiency of ballistic and laser lithotripsy with the combined use of both techniques. Data of 312 patients underwent mini-PNL for renal stones with Hounsfield Unit > 1000 was investigated retrospectively. We identified 104 patients underwent combined ballistic and laser lithotripsy. Propensity score technique was used to create the laser and ballistic lithotripsy groups. Groups were matched on stone size, stone density, and Guy's stone score. Primary end point of the study was to compare the stone free rate (SFR), complication rates, and duration of surgery. Mean age of the population was 49.4 ± 6.1, stone size was 24.6 ± 6.3mm, and stone density was 1215 ± 89 HU. The groups were similar for age, stone size, stone density, and Guy's stone score. The SFR and the complication rates of the 3 groups were similar (p = 0.67). The duration of the surgery was shorter in the combined group (46.1 ± 6.3min) compared to the laser lithotripsy (54.5 ± 6.6min) and ballistic lithotripsy (57.2 ± 6.9min) groups. Both laser and ballistic lithotripsy are effective methods for stone fragmentation during mini-PNL. Combined use of both methods has the potential to improve the fragmentation rates and diminish the operative times in case of high density stones.

Is Absence of Hydronephrosis a Risk Factor for Bleeding in Conventional Percutaneous Nephrolithotomy.

There is conflict of evidence regarding whether absence of hydronephrosis is a risk factor for bleeding in percutaneous nephrolithotomy (PNL). Moreover, among the stone complexity scoring system used for PNL (Guy's stone score, the S.T.O.N.E. nephrometry and the CROES nomogram), only the S.T.O.N.E. nephrometry score incorporates hydronephrosis as a risk factor. Therefore, this study aimed to compare perioperative outcomes according to the presence or absence of hydronephrosis in percutaneous nephrolithotomy (PCNL) patients and to investigate whether absence of hydronephrosis is a risk factor for blood transfusion rate. 281 patients who had undergone PCNL between December 2009 and April 2017 were divided according to the absence or presence of hydronephrosis (group I and group II, respectively). Perioperative outcomes were compared between the two groups. A multivariable regression analysis was performed to investigate whether hydronephrosis was a risk factor for blood transfusion rate. Patients without hydronephrosis showed significantly longer operation time and admission period, lower stone-free rate and higher blood transfusion rate compared to patients with hydronephrosis (p < 0.05, p = 0.002, p = 0.011, and p < 0.05, respectively). Multivariate logistic regression analysis showed that hydronephrosis was a significant risk factor for blood transfusion (OR, 95% CI and p value was 0.353, 0.163-0.761 and 0.008, respectively). Based on the results of the current study, we found that absence of hydronephrosis was a significant risk factor for blood transfusion in conventional PCNL.

Validation of S.T.O.N.E nephrolithometry and Guy's stone score for predicting surgical outcome after percutaneous nephrolithotomy.

Background:The aim of this study was to validate and compare Guy's and S.T.O.N.E. scoring systems in predicting perioperative and postoperative outcome following percutaneous nephrolithotomy (PCNL).Materials and Methods:From November 2015 to June 2017, 190 patients with renal stones who underwent single tract unilateral PCNL in the prone position were included in our study. Guy's and S.T.O.N.E. nephrolithometry scores were calculated in each case based on preoperative computed tomography images. The association of these scoring systems with stone-free status, length of hospital stay, operative time, and postoperative complications was studied. Regression analysis was done, and receiver operating characteristic curves were plotted.Results:Mean S.T.O.N.E. and Guy's stone scores were 8.76 ± 2.29 and 2.70 ± 1.0, respectively. When compared with patients with residual stones, stone-free (SF) patients had significantly lower mean Guy's score (2.58 ± 1.01 vs. 3.23 ± 0.77 [P < 0.001]) and S.T.O.N.E. scores (8.44 ± 2.24 and 10.17 ± 2.0 [P < 0.001]), respectively. On logistic regression analysis, both Guy's score (odds ratio [OR] = 0.48, P = 0.001) and S.T.O.N.E score (OR = 0.78, P = 0.001) were found to be significantly associated with SF status. Both of these scoring systems were also significantly associated with longer operative time (>90 min), prolonged hospital stay (>3 days) and overall complications. No significant difference was found in the area under curve for both scoring systems for stone clearance.Conclusion:Both the S.T.O.N.E and Guy's scoring systems were found to predict the outcome of PCNL, either of these could be used in the routine clinical practice for patients' counseling.

Comparison of Stone-free Rate, Operation Procedure, and Complication Rate According to guy's Stone Score in Supine Percutaneous Nephrolithotomy

Background and Aim: Percutaneous nephrolithotomy (PCNL) was considered a safe and efficient method for removing kidney stones, with a low incidence of complications. This study aims to compare the success rate of PCNL based on guy's stone score (GSS) operating procedure and its complications. Methods: Data were collected from patients with kidney stones who underwent PCNL. A stone-free rate (SFR) was considered if the patient was either had no stone or had any stone that is &lt;4 mm and asymptomatic residual fragment. Complications were assessed using the modified Clavien score, and SFR was assessed by abdominal radiography. Results: A total of 198 patients were included in this study. There was a significant difference in SFR between simple (GSS I and II) and complex stone (GSS III and IV) groups (P = 0.000). The operation procedure was longer in the complex group compared to the simple groups for both total operating time and stone fragmentation time (P = 0.000). X-ray time was not significantly different (P = 0.061). Almost all patients were classified as Clavien I, as there was no significant difference between the two groups for complication (P = 0.277) or blood loss (P = 0.176). Conclusion: The success rate of PCNL based on the GSS at Gunung Jati Regional Hospital is quite good. There was a difference in the SFR between the groups, and the operating procedure time was longer in the complex stone group. There was no difference between the simple stone and complex stone groups in PCNL complications, which indicated a good surgical practice.