Mordechai Duvdevani

Supine versus prone position during percutaneous nephrolithotomy: a report from the clinical research office of the endourological society percutaneous nephrolithotomy global study.

PURPOSEnTo determine differences in patients characteristics, operative time and procedures, and perioperative outcomes between prone and supine positioning in percutaneous nephrolithotomy (PCNL) using the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study database.nnnPATIENTS AND METHODSnBetween November 2007 and December 2009, prospective data were collected on a total of 5803 consecutive patients who were treated over a 1-year period at each of 96 participating global centers. Patients with data on body position were dichotomized into prone or supine PCNL.nnnRESULTSnThe majority of PCNL treatments were performed in the prone position (n=4637; 80.3% of sample). Differences in patient characteristics included in the prone group: A greater proportion of males (57.4% vs 52.2%); younger age (48.8u2009y vs 51.0u2009y); less frequent history of shockwave lithotripsy (19.5% vs 28.6%); greater frequency of American Society of Anesthesiologists score of 1 (54.7% vs 46.8%); and a Clavien grade of 2 or more (10.0% vs 7.2%). The mean operative time was significantly lower for prone vs supine PCNL (82.7u2009min vs 90.1u2009min) regardless of the method of tract dilation, while the stone-free rate was significantly higher (77.0% vs 70.2%). Compared with supine patients, prone patients exhibited higher rates of blood transfusions (6.1% vs 4.3%) and fever (11.1% vs 7.6%), but lower rates of failed procedures (1.5% vs 2.7%).nnnCONCLUSIONSnSince operative time and stone-free rates favor prone PCNL, but patient safety favors supine PCNL, the choice of patient position should be tailored to individual patient characteristics and the surgeons preference.

Extracorporeal shock wave lithotripsy in prepubertal children: 22-year experience at a single institution with a single lithotriptor.

PURPOSEnThe sophistication of percutaneous nephrolithotomy and ureteroscopy challenges the efficacy of ESWL for urolithiasis in prepubertal patients. We evaluated our long-term experience with ESWL in these patients and determined its efficiency.nnnMATERIALS AND METHODSnWe retrospectively reviewed the charts of all prepubertal patients who underwent ESWL. We evaluated the need for tubing, the 3-month stone-free rate, the need for additional ESWL, and the effect of stone size and location, and cystinuria on the 3-month stone-free rate.nnnRESULTSnBetween 1986 and 2008, 119 males and 97 females with a mean age of 6.6 years who had urolithiasis underwent ESWL using the Dornier HM3 lithotriptor. We treated 157 children with renal calculi with an average +/- SD diameter of 14.9 +/- 8.9 mm, of whom 66 (42%) required a tube in the urinary system. The 3-month stone-free rate was 80% and 31 patients (19.7%) needed an additional procedure. Stone location did not affect the stone-free rate but stone size did. We treated 59 patients for ureteral stones with an average stone length of 9.5 +/- 4.8 mm, of whom 41 (69%) required tube insertion. The 3-month stone-free rate was 78% and 13 patients (22%) needed an additional procedure. The 3-month stone-free rate did not depend on stone location or size. The rate was 37.5% in patients with cystinuria and 82.5% in all others (p <0.0001). Six patients (2.8%) had complications.nnnCONCLUSIONSnThe 3-month stone-free rate after ESWL in prepubertal patients is 80% and 20% of patients require additional procedures. ESWL is most effective for kidney stones less than 11 mm. ESWL has inferior results for cystine stones compared to other calculi. Complications are rare.

Ethanol and Polyvinyl Alcohol Mixture for Transcatheter Embolization of Renal Angiomyolipoma

OBJECTIVEnThe purpose of this study was to assess the immediate and midterm effects of embolization of the angiogenic component of renal angiomyolipoma in which a mixture of ethanol and polyvinyl alcohol is used as a permanent obliterator.nnnMATERIALS AND METHODSnSeventeen patients with 18 renal angiomyolipomas (size range, 5.5-20 cm; mean size, 10 cm) were treated with transcatheter embolization over an 8-year period. Embolization was performed with a mixture of 96% ethanol and polyvinyl alcohol particles. Follow-up with CT (mean follow-up period, 22.4 months) and one (mean, 14 months) or two (mean, 27 months) angiographic examinations were conducted to evaluate changes in the size of the tumor and to look for recurrence of the angiogenic component.nnnRESULTSnAll initial angiograms showed the characteristic tortuous, hypervascular, and aneurysm-forming angiogenic component. Immediate complete obliteration was achieved in 17 tumors (94.4% technical success rate). There was one partial technical failure. Mean tumor size was reduced to 7.6 cm (mean size reduction, 24%). Fourteen patients with 15 tumors underwent one angiographic follow-up examination (mean time after treatment, 14 months), and four patients underwent two angiographic follow-up examinations (mean time after treatment, 27 months). Reduction of the angiogenic component occurred in 10 (66.6%) of the tumors and complete obliteration in five (33.3%) of the tumors. No retroperitoneal hemorrhage or tumor growth was seen during the follow-up period. No complications were encountered.nnnCONCLUSIONnWe found a mixture of ethanol and polyvinyl alcohol an efficient embolizing agent with a sustained midterm effect in the management of renal angiomyolipoma. Repeated embolization was needed in tumors with a large angiogenic component. Tumor shrinkage after embolization was minimal.

Determination of Renal Stone Composition with Dual-Energy Computed Tomography: An Emerging Application

Urinary tract stone disease is common in the Western world. Nonenhanced computed tomography (CT) is the method of choice for stone diagnosis; however, it has a limited role in predicting stone type. Knowledge of stone composition is currently determined by postoperative assessment of stone fragments. A noninvasive tool for accurate characterization of stone composition would improve patient management. Dual-energy CT aids in the differentiation among calcium, uric acid, and cystine stones. In this review we describe the role of dual-energy CT for in vitro and in vivo analysis of urinary stones. We illustrate the technique, review the literature, and discuss future directions.

Superiority of the VQZ Over the Tubularized Skin Flap and the Umbilicus for Continent Abdominal Stoma in Children

PURPOSEnStricture prevention, avoiding exposed mucosa and cosmesis are important considerations when constructing continent abdominal stomas. We analyzed our results of continent abdominal stomas using the umbilicus and 2 types of lower abdominal stomas, that is the V-quadrilateral-Z technique and the tubular skin flap.nnnMATERIALS AND METHODSnPatient charts were reviewed retrospectively. All patients with a continent abdominal stoma were included in our study. Patients were divided into 3 groups according to type of stoma, including umbilicus, tubular skin flap and V-quadrilateral-Z. The groups were compared regarding demographics, etiology, success, complications and the need for revision.nnnRESULTSnA total of 40 incontinent patients were included in our study. All underwent Mitrofanoff urinary diversion (37) and/or Malone antegrade continence enema construction (13) between 1993 and 2007. The umbilicus was used for 31 conduits, the V-quadrilateral-Z was used for 8 and the tubular skin flap was used for 11. Patient age and gender, and the etiology of incontinence were similar in the 3 groups. All patients achieved good cosmesis with a hidden bowel mucosa. In the V-quadrilateral-Z group no patient had stomal stenosis. Five patients (45%) in the tubular skin flap group required dilation or revision for obstruction or stenosis, which was successful in 4. Eight umbilical conduits (25%) had to be dilated or revised due to stomal stenosis (6) and conduit obstruction (2).nnnCONCLUSIONSnInitial results with the V-quadrilateral-Z flap show its superiority over the tubular skin flap and the umbilicus for stomal construction in patients with a Mitrofanoff or Malone antegrade continence enema conduit.

Radical cystectomy vs. chemoradiation in T2-4aN0M0 bladder cancer: A case-control study

BACKGROUNDnMuscle-invasive bladder cancer is most commonly treated by radical cystectomy. Patients who are too sick to go through this surgery or who are unwilling to accept the mutilation associated with it are referred to chemoradiation. We compared the results of these 2 modalities using age-matched populations.nnnPARTICIPANTS AND METHODSnBetween 1998 and 2008, 33 patients were treated with chemoradiation for biopsy-proven T2-4aN0M0 urothelial bladder cancer. For every patient treated with chemoradiation, an age-matched patient who underwent radical cystectomy on the same year was selected for comparison. Mean radiotherapy dose was 62 Gy (standard deviation = 8.4) and median follow-up of both groups was approximately 36 months.nnnRESULTSnThe groups were similar in age, proportion of men, and length of follow-up. However, the Charlson comorbidity index was significantly lower for operated patients (3.45 vs. 4.36, P = 0.01). Furthermore, 2 patients (6%) in the chemoradiation group had salvage cystectomy (one for disease recurrence and another for bladder shrinkage). The 2- and 5-year overall survival rates after surgery were 74.4% and 54.8%, respectively, and after chemoradiation were 70.2% and 56.6% (P = 0.8), respectively. The 2- and 5-year disease-free survival rates after surgery were 67.8% and 63.2%, respectively, and after chemoradiation were 63% and 54.3% (P = 0.89), respectively. Side effects were mild in both groups, with grade 3+toxicity seen in only 2 operated and 4 irradiated patients.nnnCONCLUSIONSnDespite having a significantly higher comorbidity index, patients treated with chemoradiation had similar overall and disease-free survival rates with low toxicity. Treatment with chemoradiation should be considered in patients with T2-4aN0M0 bladder cancer.

X-ray diffraction and SEM study of kidney stones in Israel: quantitative analysis, crystallite size determination, and statistical characterization

Urinary calculi have been recognized as one of the most painful medical disorders. Tenable knowledge of the phase composition of the stones is very important to elucidate an underlying etiology of the stone disease. We report here the results of quantitative X-ray diffraction phase analysis performed on 278 kidney stones from the 275 patients treated at the Department of Urology of Hadassah Hebrew University Hospital (Jerusalem, Israel). Quantification of biominerals in multicomponent samples was performed using the normalized reference intensity ratio method. According to the observed phase compositions, all the tested stones were classified into five chemical groups: oxalates (43.2%), phosphates (7.7%), urates (10.3%), cystines (2.9%), and stones composed of a mixture of different minerals (35.9%). A detailed analysis of each allocated chemical group is presented along with the crystallite size calculations for all the observed crystalline phases. The obtained results have been compared with the published data originated from different geographical regions. Morphology and spatial distribution of the phases identified in the kidney stones were studied with scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). This type of detailed study of phase composition and structural characteristics of the kidney stones was performed in Israel for the first time.

External Validation of CROES Nephrolithometry as a Preoperative Predictive System for Percutaneous Nephrolithotomy Outcomes.

PURPOSEnWe externally validated CROES (Clinical Research Office of the Endourological Society) nephrolithometry and evaluated the predictive accuracy of the nomogram.nnnMATERIALS AND METHODSnData were collected on patients who underwent percutaneous nephrolithotomy between January 2012 and February 2015. The CROES nomogram was applied to all patients and externally validated. The AUC and calibration plot were used for discrimination and clinical validity assessment.nnnRESULTSnA total of 176 patients were included in study. Mean ± SD patient age was 55.2 ± 13.9 years and the mean stone burden was 640.0 ± 911.4 mm(2). The CROES nomogram was significantly associated with stone number, location and burden, and the number of implicated calyces, punctures and tracts. The postoperative treatment success rate was 85.8%. The number of stones, number of implicated calyces and CROES score were independent predictors of treatment success. The estimated AUC was 0.715 and the model provided good calibration.nnnCONCLUSIONSnThe CROES nomogram is an accurate tool to estimate renal stone complexity. CROES nephrolithometry provides great accuracy to predict postoperative efficacy.

Pre‐operative double J stent placement in ureteral and renal stone treatment: results from the Clinical Research Office of Endourological Society URS Global Study

To compare outcomes of ureteric and renal stone treatment with ureteroscopy (URS) in patients with or without the placement of a preoperative JJ stent.

Impact of stone density on outcomes in percutaneous nephrolithotomy (PCNL): an analysis of the clinical research office of the endourological society (CROES) pcnl global study database

Abstract Objective. This study aimed to explore the relationship between stone density and outcomes of percutaneous nephrolithotomy (PCNL) using the Clinical Research Office of the Endourological Society (CROES) PCNL Global Study database. Material and methods. Patients undergoing PCNL treatment were assigned to a low stone density [LSD, ≤ 1000 Hounsfield units (HU)] or high stone density (HSD, > 1000 HU) group based on the radiological density of the primary renal stone. Preoperative characteristics and outcomes were compared in the two groups. Results. Retreatment for residual stones was more frequent in the LSD group. The overall stone-free rate achieved was higher in the HSD group (79.3% vs 74.8%, p = 0.113). By univariate regression analysis, the probability of achieving a stone-free outcome peaked at approximately 1250 HU. Below or above this density resulted in lower treatment success, particularly at very low HU values. With increasing radiological stone density, operating time decreased to a minimum at approximately 1000 HU, then increased with further increase in stone density. Multivariate non-linear regression analysis showed a similar relationship between the probability of a stone-free outcome and stone density. Higher treatment success rates were found with low stone burden, pelvic stone location and use of pneumatic lithotripsy. Conclusions. Very low and high stone densities are associated with lower rates of treatment success and longer operating time in PCNL. Preoperative assessment of stone density may help in the selection of treatment modality for patients with renal stones.