Initial Stone-free Rate Research Articles

Safety and efficacy of minimally invasive percutaneous nephrolithotomy in the treatment of patients with medullary sponge kidney.

The purpose of this study was to review the safety and efficacy of the minimally invasive percutaneous nephrolithotomy in the treatment of medullary sponge kidney patients with complex renal calculi. Sixteen medullary sponge kidney patients with complex renal calculi underwent minimally invasive percutaneous nephrolithotomy procedures in our center were entered into this retrospective study. The data analyzed included patients' demographics, stone burden, operative time, operative blood loss, length of hospital stay, complications according to the modified Clavien system, and stone-free rate. All the patients in this study had complex renal stones that included 14 multiple stones and 3 partial staghorn calculi. The mean stone surface area was 779.5±421.1mm(2). Preoperative urinary tract infection was noted in 5 (31.2%) patients. Minimally invasive percutaneous nephrolithotomy was successfully completed in 15 renal units in 14 patients. Two patients failed the procedure. The mean operative time was 87.3±32.3min. Mean hemoglobin drop was 25.3±16.5g/L. An initial stone-free rate of 60% was achieved after the procedure, and the final stone-free rate was 86.6% after auxiliary second look and/or shock-wave lithotripsy. Clavien grade I and II complications occurred in 3 (21.4%) patients including the one (7.1%) patient who required transfusion. All the complications were managed conservatively. No major complications occurred. This retrospective analysis confirmed that minimally invasive percutaneous nephrolithotomy was a safe alternative treatment for the medullary sponge kidney patients with complex renal calculi. This procedure provided an acceptable stone-free rate and low incidence of high-grade complications. Stone-free rate further could be further improved with auxiliary procedures.

Supine pediatric percutaneous nephrolithotomy (PCNL)

Many authors reported their experience with supine PCNL in adult population comparing the outcome with prone PCNL and they found that the stone free rate and the operative time were in favor of prone PCNL with a lower patient morbidity among patients with supine PCNL. This encouraged us to perform supine PCNL in pediatric population. In this study we evaluated the safety and efficacy of supine PCNL in pediatric population. Between April 2011 and February 2014 a total of 27 children (6 girls and 21 boys) presented with renal calculi. The stones were single pelvic stone in 14 cases, pelvic stone with lower calyceal stones in 7 cases and pelvic stone with upper calyceal stones in 6 cases. The mean stone size was 32 mm (range 20-47 mm). All patients were managed with supine PCNL performed by a single surgeon. Marking the posterior axillary line in standing position before the operation is a mandatory initial step. The patients were placed in supine position with elevation of the ipsilateral shoulder and hip by means of two bags one underneath the shoulder and the other underneath the hip to widen the operative field. The technique was performed using a sheathless 19 fr. Richard wolf rigid nephroscope after acute tract dilation by amplatz dilators. Complications (intraoperative and postoperative) and stone free rate rates were reported. A single lower calyceal access was used in all cases through which we could successfully remove even the upper calyceal stones. Kinking of the guide wire during tract dilatation were encountered in 4 cases and the guide wire was successfully exchanged using a small Teflon dilator in 2 cases while ultrasonographic guided lower calyceal repuncture was done in 2 cases. The average operative time (from the beginning of the puncture trial to nephrostomy tube insertion) was (41 ± 15) min. The operation was successfully completed as planned in all cases with two cases of intraoperative complications (one case of pelvicalyceal system perforation and another case of intraoperative bleeding and blood transfusion). The initial stone free rate was (92.5%). Postoperative complications was reported in the form of 2 cases of fever that respond to medical treatment for 72 h. The main advantages of supine pediatric PCNL is that it is comfortable for the surgeon, the anesthetist and the child. The main disadvantages of supine pediatric PCNL is that it is not familiar for most urologists and small field of operation. The short outcome of our study is the small number of cases and the lack of comparative study with prone pediatric PCNL. Pediatric supine PCNL is a safe and effective method for management of pediatric renal stones. It carries the advantages of easily upper calyx access through the lower calyceal tract, low incidence of fluid absorption or hypothermia and easy anesthesia monitoring. However a larger number of cases are needed to be evaluated.

Comparison Between Extracorporeal Shock Wave Lithotripsy and Ureteroscopic Lithotripsy for Treating Large Proximal Ureteral Stones: A Meta-analysis

To compare extracorporeal shock wave lithotripsy (ESWL) and ureteroscopic lithotripsy (URSL) in terms of efficacy, complications, and overall efficiency in the management of proximal ureteral calculi. ESWL and URSL are the 2 most common modalities for treating ureteral stones. Previous studies and meta-analyses suggest that for stones<10mm, ESWL is safer and of comparable efficacy compared with URSL. However, the choice between one modality over the other for the treatment of stones >10mm is not as clear. The literature was reviewed in the databases, and resulting reports were screened for relevance. This process yielded 10 articles, which were analyzed in terms of the initial stone-free rate (primary outcome measure) compared between the 2 treatment modalities. Pretreatment rate, operation time, auxiliary procedure rate, and complication rate constituted secondary measures in the analysis. A statistically higher initial stone-free rate was demonstrated for URSL compared with ESWL (odds ratio [OR]= 0.349; 95% confidence interval [CI]= 0.183-0.666; P= .001). ESWL showed a statistically higher retreatment rate compared with URSL (OR= 7.192; 95% CI= 4.934-10.482; P<.001). The 2 treatment modalities did not show statistically significant differences in mean operating time (OR= 10.35; 95% CI=-0.29 to 20.99; P= .056), auxiliary procedure rate (OR= 1.043; 95% CI= 0.415-2.616; P= .929), or in the complication rate (OR= 0.78; 95% CI= 0.304-1.984; P= .598). For treating large (>10mm) proximate ureteral stones, URSL tends to be more effective than ESWL, yet without adding significant risk.

Editorial Comment

The authors1 performed a meta-analysis comparing outcomes of shock wave lithotripsy and ureteroscopic lithotripsy for stones >10 mm. A higher initial stone-free rate and lower retreatment rate were found for those treated ureteroscopically; complications were similar between the 2 groups. An important consideration, alluded to in the discussion, is that shock wave lithotripsy technology has remained stagnant with the Dornier HM3 lithotripter, still considered the gold standard in terms of efficacy.

Efficacy of endoscopic combined intrarenal surgery in the prone split-leg position for staghorn calculi.

Abstract Purpose: To evaluate the efficacy of endoscopic combined intrarenal surgery (ECIRS) using retrograde flexible ureteroscopy and miniature percutaneous nephrolithotomy (PNL) for the treatment of patients with staghorn calculi in the prone split-leg position. We retrospectively reviewed the records of 42 patients with staghorn calculi (45.8±3.2 mm) who underwent ECIRS using retrograde flexible ureteroscopy and miniature PNL in the prone split-leg position for the treatment of staghorn calculi in our center between December 2010 and August 2013. A flexible ureteroscope with a laser fiber was inserted through a ureteral access sheath, and lithoclast lithotripsy was performed through a mini-percutaneous tract. Both procedures were performed simultaneously by two urologists. Surgical parameters, including surgical time, stone-free (SF) rates, modified Clavien complication grades, and risk factors for residual stones, were analyzed. Fifteen patients (35.7%) had complete staghorn calculi. Among the 42 staghorn calculi treated, 23 had 0 to 5 stone branches, 14 had 6 to 10 stone branches, and 5 had ≥11 stone branches. All procedures were performed successfully using a single lithotripsy tract with the patient in the prone split-leg position. The mean surgical time was 143.2±9.2 minutes. The initial SF rate was 71.4%, and the final SF rate was 83.3% after further treatment. One patient required a blood transfusion (2.4%), but no patient experienced a ≥3 Clavien grade complication. Risk factors for residual stones were stone size, stone surface area, complete staghorn calculi, and the number of stone branches. ECIRS for staghorn calculi in the prone split-leg position is a safe, efficient, and versatile method for the effective management of staghorn calculi without the creation of multiple percutaneous tracts.

Developments in the Technique of Endoscopic Combined Intrarenal Surgery in the Prone Split-leg Position

To develop a new technique for performing endoscopic combined intrarenal surgery in the prone split-leg position and to evaluate its efficacy using computed tomography. Between December 2010 and January 2013, 60 patients with large calculi (39.2 ± 2.6 mm) underwent this surgery. A laser fiber was used with a flexible ureteroscope introduced through a ureteral access sheath, and lithoclast lithotripsy was performed through a mini-percutaneous tract. Three-dimensional computed tomography was performed to determine anatomic variations, including the ureteral location and ureteropelvic junction angle in all patients in both the supine and prone positions. All procedures were performed successfully with a single tract and the patient in the prone split-leg position. The mean surgical time was 120.5 ± 6.7 min. The initial stone-free rate was 82%, and the final stone-free rate was 87% after further treatment. One patient required blood transfusion, but none had severe complications. Computed tomography showed that the ureter between the orifice and ureteropelvic junction was straighter and the ureteropelvic junction angle was significantly smaller for surgeries conducted in the prone position than the supine position. Flexible ureteroscopy in the prone split-leg position is a viable technique. It allows easy insertion of the ureteral sheath and access of the ureteroscope to the renal pelvis. The findings suggest that this hybrid surgery is an efficient, effective, and versatile procedure for the management of renal calculi.

Analgesic Use and Complications Following Upper Pole Access for Percutaneous Nephrolithotomy

Upper pole access (UPA) to the kidney optimizes working angles during percutaneous nephrolithotomy (PCNL). However, many surgeons are hesitant to employ UPA due to concerns for increased postoperative pain and complications. In this study, we compare perioperative pain and outcomes for PCNL performed through UPA with middle and lower pole access (LPA). A retrospective review of PCNLs performed at a single academic institution between 2002 and 2012 was performed. Patient demographics, stone burden, operative characteristics, length of hospital stay, and perioperative complications were recorded. Narcotics administered on postoperative days (POD) 1 and 2 were converted to intravenous morphine equivalents. The Mann-Whitney U, Fisher's exact test, and logistic regression analyses were used for statistical comparison. Of 350 PCNLs performed on 269 patients, 125 patients underwent primary PCNL through single tract UPA, while primary LPA was utilized in 138 patients. Patients with multiple access tracts (n=6) were excluded. Baseline characteristics between groups were similar except for age; patients with UPA were older (52.6 vs. 46.2 years; p=0.003). Stone burden, operative time, and initial stone-free rate were comparable between groups. Additionally, analgesic requirements were similar on POD 1 (p=0.54) and 2 (p=0.62). There was no difference in the overall complications (p=0.23) or thoracic complications (p=0.43). Although both groups had equivalent stone-free rates after initial PCNL (p=0.78), those with residual stones had a superior stone-free rate after second-look PCNL through UPA (73.3% vs. 44.3%, p=0.035) and a superior overall stone-free rate (94.4% vs. 86.2%, p=0.037). Patients undergoing PCNL through UPA had a higher ultimate stone-free rate compared with LPA, while postoperative analgesic requirements and overall complication rates were similar between access sites. A trend toward higher thoracic complication rates was observed in the UPA group, although this did not reach statistical significance. Surgeons should not hesitate to utilize UPA when indicated for patients with large or complex stones.

Minimally Invasive Percutaneous Nephrolithotomy for Simple and Complex Renal Caliceal Stones: A Comparative Analysis of More Than 10,000 Cases

To determine whether minimally invasive PCNL (MPCNL) is as safe and effective in the management of complex renal caliceal stones as it is for simple renal stones. We retrospectively reviewed 5761(41.2%) simple caliceal stones (isolated renal pelvis including isolated calix) and 8223 (58.8%) complex caliceal stones (renal pelvis accompanying two calices at least) that were managed by MPCNL between 1992 nd 2011. The safety, efficacy, and outcome were compared and analyzed. Stone burden was larger in complex caliceal stones (1763.0 vs 1018.6 mm(2), P<0.05). Patients with simple stones had significantly shorter operative time, less frequency of multiple percutaneous accesses, and less hemoglobin drop. They also had a higher initial stone-free rate (SFR) (77.6% vs 66.4%) after a single session of MPCNL (P<0.05). The differences diminished in the final SFR (86.7% vs 86.1%) after relook and/or auxiliary procedures (P>0.05). The complication rate (17.9% vs 19.0%) and blood transfusion rate (grade II) (2.2% vs 3.2%) were similar in both groups (P>0.05). Both groups had a low rate of high Clavien grade complications. Renal vascular embolizations (grade III), however, were significantly higher in patients with complex caliceal stones (P<0.05). MPCNL is a safe and effective treatment option for patients with complex caliceal stones except there is a slightly higher frequency rate of embolization. There was a higher initial SFR in simple stones, but this difference diminished with secondary procedures.

Evaluation of a Novel Fascial Dilator Modified with Scale Marker in Percutaneous Nephrolithotomy for Reducing the X-Ray Exposure: A Randomized Clinical Study

To evaluate the role of the fascial dilators modified with a scale marker in reducing fluoroscopy time during percutaneous nephrolithotomy (PCNL). In a randomized clinical trial, eligible 100 consecutive patients anticipated to undergo single-tract PCNL were randomly assigned into two groups by the closed envelope method, to compare the efficacy and safety of the modified scale fascial dilator (group 1, n=50) and traditional nonscale fascial dilator (group 2, n=50) with respect to the X-ray exposure duration as well as the outcome of PCNL. There was no significant difference between group 1 and group 2 regarding to the initial successful access rate (100% v 96%), operative time (79.4 v 83.7 minutes), the initial stone-free rate (82% v 81.3%), complications (24% v 20%), and bleeding required blood transfusion (4% v 6%) (all p>0.05). The mean operative duration and fluoroscopic time for tract dilation in group 1 and group 2 were 164.4 ± 19 seconds v 168.3 ± 14 seconds, and 3.2 ± 0.9 seconds v 22.2 ± 4.6 seconds, (p=0.250 and p<0.001), respectively. Compared to the use of nonscaled dilators, using the scaled fascial dilators for a percutaneous access in PCNL was found to be associated with less radiation hazards along with similar stone-free rate and complications.

Comparison of Children versus Adults Undergoing Mini-Percutaneous Nephrolithotomy: Large-Scale Analysis of a Single Institution

ObjectiveAs almost any version of percutaneous nephrolithotomy (PCNL) was safely and efficiently applied for adults as well as children without age being a limiting risk factor, the aim of the study was to compare the different characteristics as well as the efficacy, outcome, and safety of the pediatric and adult patients who had undergone mini-PCNL (MPCNL) in a single institution.MethodsWe retrospective reviewed 331 renal units in children and 8537 renal units in adults that had undergone MPCNL for upper urinary tract stones between the years of 2000–2012. The safety, efficacy, and outcome were analyzed and compared.ResultsThe children had a smaller stone size (2.3 vs. 3.1 cm) but had smilar stone distribution (number and locations). The children required fewer percutaneous accesses, smaller nephrostomy tract, shorter operative time and less hemoglobin drop. The children also had higher initial stone free rate (SFR) (80.4% vs. 78.6%) after single session of MPCNL (p<0.05); but no difference was noted in the final SFR (94.7% vs. 93.5%) after auxiliary procedures. The complication rate (15.6% vs. 16.3%) and blood transfusion rate (3.1% vs. 2.9%) were similar in both group (p>0.05). Both groups had low rate of high grade Clavien complications. There was no grade III, IV, V complications and no angiographic embolization required in pediatric group. One important caveat, children who required multiple percutaneous nephrostomy tracts had significant higher transfusion rate than in adults (18.8% vs. 4.5%, p = 0.007).ConclusionsThis contemporary largest-scale analysis confirms that the stone-free rate in pediatric patients is at least as good as in adults without an increase of complication rates. However, multiple percutaneous nephrostomy tracts should be practiced with caution in children.

Treatment of upper urinary calculi with Chinese minimally invasive percutaneous nephrolithotomy: a single-center experience with 12,482 consecutive patients over 20 years

The Chinese minimally invasive percutaneous nephrolithotomy (MPCNL) was a modified version of standard PCNL which utilizes smaller tract and sheaths. The aim of this study was to present our experience on its efficacy and safety, and to grade its complications according to the modified Clavien classification. Between 1992 and 2011, 12,482 patients who underwent 13,984 MPCNL procedures entered this study. Data on stone size, access number, operative time, hospital length of stay, stone-free rate (SFR), and complications according to the modified clavien system were evaluated prospectively. Their mean age of patients was 47.6years (range 0.6-93). The mean stone size was 3.2±0.8 (1.4-7.4)cm. The mean operative time was 83±38min. Mean hemoglobin drop was 13.5±11.3g/L. Mean hospital stay was 10.3±6.4days (2-22days). The initial SFR after first procedure was 78.6%. In 14.7% of cases with a second look, the SFR increase to 89.9%. At 3months after auxiliary procedures (re-PCNL, ureterorenoscopy, and shock wave lithotripsy), the overall SFR was achieved to 94.8%. A total of 3,624 complications (25.92%) were observed in 2,591 (18.53%) procedures. There were 2,355 grade I (16.84%), 706 grade II (5.05%), 553 grade III (3.95%), 7 grade IV (0.05%), and three death of grade V (0.02%) complications. This large-scale, contemporary analysis confirms MPCNL is still a safe and efficacious treatment option of kidney stones with a high stone-free rate and uncommon rate of high grade complications.

Two-step Minipercutaneous Ureterolithotripsy Under Multimodal Analgesia for Complicated Impacted Calculi in Proximal Ureter

To suggest minipercutaneous ureterolithotripsy using the mininephroscope as an alternative process for impacted stones of the upper ureter because these stones can be challenging to treat and can produce severe symptoms. We report our results of cases in which the percutaneous approach using 2-step minipercutaneous ureteroscopy with the mininephroscope was used to achieve relief from the stone, with minimal anesthesia risks. A total of 54 patients (33 men and 21 women) presented with impacted stones in the proximal ureter. The mean stone size was 16.2mm (range 10-21). All patients were treated with 2-step minipercutaneous antegrade ureterolithotripsy under multimodal analgesia. The mean operative time was 49 minutes (range 40-110). Placement of the percutaneous drainage tube was quick and was performed with the patient under local anesthesia. The minipercutaneous session followed several days later, with the patient under multimodal anesthesia. The initial stone-free rate was 94%. The stone-free rate 2 months after the procedure was 100%. All procedures were well tolerated by the patients (group mean visual analog scale score 3.1 ± 0.7 standard deviation). No severe adverse events were noted. The mean hospital stay was 5.3 days (range 3-12). In selected emergency cases of impacted proximal ureteral stones, the approach of the initial insertion of a nephrostomy tube followed by a second session of antegrade ureterolithotripsy using the mininephroscope is a safe and effective alternative treatment, especially, because it can be accomplished with minimal anesthesia requirements.

Treatment of large impacted proximal ureteral stones: randomized comparison of minimally invasive percutaneous antegrade ureterolithotripsy versus retrograde ureterolithotripsy

To provide appropriate evidence for treatment planning of patients with an impacted proximal ureteral stones ≥1.5 cm in size, by analyzing the therapeutic outcomes for those undergoing minimally invasive percutaneous antegrade ureterolithotripsy and retrograde ureterolithotripsy. From September 2010 to November 2011, eligible patients with impacted proximal ureteral stones ≥1.5 cm in size referred to our institute were considered for this study. The closed envelope method was used to randomize the enrolled patients to mini-PCNL (30) or retrograde ureterolithotripsy (29). The efficiency quotient (EQ) was calculated to specifically address the efficiency for both the techniques. All preoperative and postoperative data for both groups were recorded. The initial stone-free rate was 93.3% in the mini-PCNL group and 41.4% in the URSL group (p < 0.001). However, the overall stone-free rate at the 1-month follow-up visit after initial treatment was 100% in the mini-PCNL group and 89.7% in the URSL group (p = 0.07). The EQs for the mini-PCNL and URSL groups were 0.83 and 0.50, respectively. Our study shows that mini-PCNL removal of large impacted proximal ureteral calculi can achieve higher stone-free rates and safe.

Management of impacted proximal ureteral stone: Extracorporeal shock wave lithotripsy versus ureteroscopy with holmium: YAG laser lithotripsy

Objective:Prospective evaluation of the efficacy and safety of the extracorporeal shock wave lithotripsy (SWL) and ureteroscopy with Holmium: YAG laser lithotripsy (URSL) as a primary treatment for impacted stone in the proximal ureter.Patients and Methods:A total of 82 patients with a single impacted stone in the proximal ureter were included in the study. Patients were allocated into two groups according to patient preference for either procedure. The first group included 37 patients who were treated by SWL and the second group included 45 patients treated by URSL. The preoperative data and treatment outcomes of both procedures were compared and analyzed.Results:There was no difference as regards to patient and stone characters between the two groups. There was significantly higher mean session number and re-treatment rate in the SWL group in comparison to URSL group (1.5 ± 0.8 vs. 1.02 ± 0.15 session, and 43.2% vs. 2.2%, respectively). At one month, the stone-free rate of the URSL group was statistically significantly higher than that of the SWL group (80% vs. 67.6%, respectively). The stone-free rate at three months was still higher in the URSL group, but without statistically significant difference (80.2% vs. 78.4%, respectively). There was no statistically significant difference in the rate of complications between the SWL and URSL (24.3% vs. 15.6%, respectively).Conclusion:Both procedures can be used effectively and safely as a primary treatment for impacted stone in the proximal ureter; however, the URSL has a significantly higher initial stone-free rate and lower re-treatment rate.

RIRS versus mPCNL for single renal stone of 2–3 cm: clinical outcome and cost-effective analysis in Chinese medical setting

The aim of the study was to compare the clinical outcome and the cost-effectiveness between retrograde intra renal surgery (RIRS) and mini-percutaneous nephrolithotripsy (mPCNL) for the management of single renal stone of 2-3cm in Chinese medical setting. From May 2005 to February 2011, 115 patients with solitary renal calculi were treated either by RIRS or mPCNL. 56 patients were in RIRS group while 59 were in mPCNL group. Patients' demographics between the two groups, in terms of gender, age, BMI, history of ESWL as well as stone side, stone location and stone size were comparable. Peri-operative course, clinical outcome, complication rates and medical cost were compared. The effective quotient (EQ) of two groups was calculated. Data were analyzed using Fisher's exact test, Chi-square test and Student's t test. EQ for RIRS and mPCNL were 0.52 and 0.90. The initial stone-free rate (SFR) of RIRS group and mPCNL group was 71.4 and 96.6%, respectively (P=0.000). The mean procedure number was 1.18 in RIRS group and 1.03 in mPCNL group, respectively (P=0.035). The operative time for RIRS was longer (P=0.000) while the mean hospital stay was shorter (P=0.000). There was no statistical difference in peri-operative complications between the groups. The initial hospitalization cost, laboratory and radiology test cost of RIRS group were lower (P=0.000). However, counting the retreatment cost in the two groups, the total medical expenditure including the overall hospitalization cost, overall laboratory and radiology test cost and post-operative out-patient department (OPD) visit cost was similar between two groups. In conclusion, with similar total medical cost, mPCNL achieved faster stone clearance and lower retreatment rate without major complications, which implied higher cost-effectiveness for the treatment of single renal stone of 2-3cm in Chinese medical setting. RIRS is also a safe and reliable choice for patients having contraindications or preference against mPCNL.

Predictive Factors for Percutaneous Nephrolithotomy Outcomes in Neurogenic Bladder Population

To review experience performing percutaneous nephrolithotomy (PCNL) on patients with neurogenic bladder, evaluating predictors for increased length of stay (LOS), intensive care unit (ICU) stay, stone-free rate, and number of procedures and outcomes measures between spinal cord injury (SCI) and spina bifida (SB) patients. We retrospectively reviewed our PCNLs from January 1, 2002 to December 31, 2009 and identified 47 patients. Data collected included LOS, ICU stay, stone-free rate, complications, and total procedures. A total of 66 PCNLs were performed on 47 patients. The mean LOS was 5.3 days, and nine patients needed ICU stay (mean 13.9 d). Initial stone-free rate was 60.6%, and final stone-free rate was 69.7%. Multiple access was associated with increased LOS (P=0.01), ICU stay (P<0.01), transfusion (P<0.01), and pulmonary complications (P=0.03). Upper-pole access was associated with decreased initial stone-free rate (P=0.04). Midpolar access predicted increased final stone-free rate (P=0.04). Mean stone size was 3.31 cm and was predictive of an increased number of procedures (P=0.04). Larger stone size was also predictive of decreased initial stone-free rate (P=0.03) and final stone-free rate (P=0.05). There were no statistically significant differences between SCI and SB patients in terms of outcomes. Increasing stone size and multiple access were predictors of adverse outcomes, and location of access affected stone-free status. We found no differences in outcomes between SB and SCI patients. To our knowledge, this is the largest series reported regarding PCNLs in this patient population.

Flank Suspended Supine Position for Percutaneous Nephrolithotomy

Prone and supine positions for percutaneous nephrolithotomy are widely used but have their drawbacks. We report a new positioning method called "flank suspended supine position" (FSSP) for PCNL and describe our experience with PCNL in this position to evaluate its safety and efficacy. Retrospective study of 150 cases of renal stone patients treated with PCNL in a new position called flank suspended supine position (FSSP) from June 2009 to July 2010. All patients were treated with PCNL in FSSP under epidural anesthesia. Operation time, bleeding rate, stone free rate, and complications were recorded. All patients tolerated FSSP. Mean operation time was 78.29±26.13 min. Initial stone-free rate was 83%. For those with residual stones (26 cases), 18 were stone-free after a second PCNL, 8 after extracorporeal shock wave lithotripsy (ESWL). Mean hospital stay was 7.63±2.39 days. No penetrating injury of the pleural cavity or injury to visceral organs was reported. FSSP is an effective and safe position for PCNL in our hands and its effectiveness relative to traditional prone position needs to be determined in future randomized studies.

Cost-Effectiveness Analysis of Ureteroscopic Laser Lithotripsy and Shock Wave Lithotripsy in the Management of Ureteral Calculi in Eastern China

Introduction: It was the aim of this study to compare the efficiency and safety between shock wave lithotripsy (SWL) and ureteroscopic holmium laser lithotripsy (URL) methods for ureteral calculi while also determining which option is more cost-effective. Patients and Methods: During January 2008 to September 2009, a prospective randomized study was conducted to compare both modalities for the management of solitary radiopaque ureteral stones. Patient and stone characteristics, treatment outcome and charges were documented. Both options were compared using univariate statistical tests to identify the efficiency quotient and cost-effectiveness for ureteral calculi according to the stone location. Results: A total of 257 patients were in the SWL group, while 269 were in the URL group. The efficiency quotients for SWL and URL were 0.81 and 0.88, respectively. The initial stone-free rate of URL for lower ureteral calculi was higher (p = 0.002), while the complication rate of SWL for upper ureteral calculi was lower (p = 0.027). The SWL group required lower hospitalization charges (USD 440 vs. 1,221; p < 0.001), lower total charges (USD 454 vs. 1,284; p < 0.001) and a shorter period of hospitalization (5.4 vs. 6.6 days; p < 0.001) compared with the URL group for all ureteral locations. For mid and lower ureteral calculi, the postoperative office visits of the URL group were fewer (1.03 vs. 1.1 times; p = 0.001). Conclusions: Primary in situ SWL for upper and middle ureteral calculi showed lower complication rates compared to URL and was more cost-effective in Eastern China. However, primary URL was a better option for treating lower ureteral stones with a higher stone-free rate but was more expensive.

Semirigid Ureteroscopy in Management of Large Proximal Ureteral Calculi: Is There Still a Role in Developing Countries?

To evaluate the outcome and complications of the use of semirigid ureteroscopy (URS) together with intracorporeal pneumatic lithotripsy in the management of upper ureteral calculi >10 mm in diameter. A total of 75 patients (41 women and 34 men), with a mean age of 48 years (range 25-60), underwent primary URS for solitary radiopaque proximal ureteral calculi 10-20 mm in diameter (average 13.1). Dilation of the intramural ureter was done in 60 cases (80% of patients), and intracorporeal lithotripsy was required in 56 (74.6%). Ureteral catheters were left for drainage in 60% of patients, 26.7% were left unstented, and only 13.3% required an indwelling stent. Of the 75 stones, 60 (80%) were successfully cleared after a single endoscopic procedure. Our initial stone-free rate was 90.6% at 2 weeks after the primary endoscopic procedure and had reached 98.6% at 3 months. Antegrade URS for migrating stones was done successfully in 6 cases in a tubeless fashion, and open ureterolithotomy was required in 1 case. No major complications were encountered. The minor complications included only mild extravasation and self-limited postoperative fever and hematuria. The risk factors for URS failure included male gender, the severity of the hydronephrosis, the severity of impaction, and the occurrence of extravasation. The results of our study have shown that semirigid URS is a safe and successful alternative to open ureterolithotomy in the management of large proximal ureteral calculi in the absence of flexible instruments.

The learning curve in minimally invasive percutaneous nephrolitholapaxy: a 1-year retrospective evaluation of a novice and an expert

The aim of this study was to compare a novice surgeon with an expert surgeon independently performing minimally invasive percutaneous neprolitholapaxy (PCNL) excluding the influence of the expert in the learning curve. Clinical records of 84 patients (novice: n = 35; expert: n = 49) undergoing minimally invasive PCNL between 04/2007 and 04/2008 were retrospectively reviewed for the following parameters: drop in hemoglobin, operative and fluoroscopy time, length of hospital stay, stone-free rate and complication rate. Complications were graded according to the Clavien classification. Statistical analysis was carried out by student's t test (Chi-square test) with p < 0.05 considered significant. The novice surgeon experienced longer median operative and fluoroscopy time, lower stone-free rate and higher re-treatment rate (all p < 0.005) but no longer length of hospital stay (p = 0.19) compared to the experienced surgeon. The novice showed a notable improvement in operating time (p = 0.0208). Altogether, 16 complications occurred in 84 minimally invasive PCNL (19.1%) with five patients (6.0%) encountering grade III complications. Four patients (8.2%) treated by the expert surgeon developed complications (all grade I/II) compared to 12 of the patients (34.3%) treated by the novice surgeon (p = 0.0265). All grade III complications occurred in the first 20 patients of the novice surgeon group. Despite longer operating time and a lower initial stone-free rate, the novice showed a significant improvement with growing experience and a low rate of higher grade (≥IIIa) complications. This demonstrates that the concept of minimally invasive PCNL can also be learned by urologists who do not have the support of an experienced colleague without endangering patient safety.