Search tips
Search criteria

Results 1-25 (207078)

Clipboard (0)

Related Articles

1.  Percutaneous management of renal caliceal diverticular stones: Ten-year experience of a tertiary care center with different techniques to deal with diverticula after stone extraction 
Caliceal diverticulae are a frequent surgical problem. We present our experience with caliceal diverticular stones (CDS) managed with percutaneous nephrolithotomy (PCNL) and describe the two different techniques to deal with diverticula after stone retrieval.
Materials and Methods:
We retrospectively analyzed 10-year data of 44 consecutive patients who underwent PCNL for CDS. During PCNL, if the guide wire could be negoted through the neck of the diverticula, we dilated and stented it. If we couldnot find the neck, we fulgurated the diverticular walls. Follow-up included intravenous urogram at 3 months and annual plain films thereafter. We analyzed the outcome, complications, and recurrence rate.
Total stone clearance was obtained in 40 (90.90%) patients. We dilated and stented the diverticula in 35 (79.5%) patients and fulgurated the walls in nine (20.5%) patients. Complications occurred in three patients. The postoperative intravenous urogram showed obliteration of diverticula in seven patients and the improved drainage in 37 patients. At the average follow-up of 2 years, 41 (93.18%) patients were asymptomatic and two (4.5%) patients showed the recurrence of stone.
PCNL can clear calculi from caliceal diverticula in most cases with minimal morbidity. After stone retrieval, the diverticula may be drained into the pyelocaliceal system, if the neck is negotiable and fulgurated if the neck cannot be dilated.
PMCID: PMC3822340  PMID: 24235786
Caliceal diverticula; Caliceal diverticular stones; percutaneous nephrolithotomy
2.  Single puncture percutaneous nephrolithomy for management of complex renal stones 
BMC Research Notes  2009;2:62.
The purpose of this report is to assess the safety and efficacy of single lower pole access for multiple and branched renal calculi. A prospective non randomized clinical study included 26 patients with complex renal stones (9 patients had branched renal stones and the other 17 had multiple renal stones) in the period from May 2003 to May 2004. Mean patient age was 42 years ± 13.2 (range 18 to 67 years). All patients underwent percutaneous nephrolithotomy (PCNL) via a single lower calyceal puncture. Small stones were intactly extracted by a range of stone graspers while large stones (smallest diameter more than 1 cm) were disintegrated using either the pneumatic EMS Swiss lithoclast or Holmium YAG laser. Flexible nephroscope was used for stones inaccessible by the rigid instruments.
Overall stone-free rate was 74.8%. Patients with residual stones were managed by one session of shock wave lithotripsy (SWL). Mean operative time was (80 minutes ± 27.4) for branched stones and (49.1 minutes ± 15.9) for multiple stones. No significant blood loss reported. Perforation of pelvicalyceal system occurred in 2 patients (11.5%) with no serious sequelae. Only 1 patient developed secondary hemorrhage which necessitated blood transfusion and selective angio-embolization.
In our hands, the efficacy and safety of single lower calyceal puncture PCNL in management of complex renal stones are comparable to those of the general procedure stated in literature.
PMCID: PMC2679047  PMID: 19379503
3.  Comparative evaluation of upper versus lower calyceal approach in percutaneous nephrolithotomy for managing complex renal calculi 
Urology Annals  2015;7(1):31-35.
Percutaneous nephrolithotomy (PCNL) is the treatment of choice for staghorn and large renal stones. The success of PCNL is highly related to optimal renal access. Upper calyceal puncture being more difficult and more demanding have relatively few studies presented.
Aims and Objectives:
This prospective study was carried out to evaluate the effectiveness and safety of upper calyceal versus lower calyceal puncture for the removal of complex renal stones through PCNL.
Materials and Methods:
A total of 94 patients underwent PCNL for complex renal stone in our institute. Fifty-one of them underwent lower calyceal, while 43 underwent upper calyceal puncture. The two approaches are compared as per total duration of surgery, intraoperative blood loss, infundibular/pelvic tear, rate of complete clearance and rate of postoperative complications (pulmonary, bleeding, fever and sepsis, etc.).
Observation and Results:
In our study, the success rate was 76.47% for those in the lower, 90.70% for those in the upper calyceal access group. Thoracic complications (hydrothorax) occurred to 1 patient in upper calyceal supracostal access group. Bleeding requiring blood transfusion happened to 5 patients in lower calyceal access and 1 in upper calyceal group.
In our study for the management of complex renal calculi, we conclude that in a previously unoperated kidney, upper calyceal puncture through subcostal or supra 12th rib is a feasible option minimizing lung/pleural rupture and gives a better clearance rate. We suggest that with due precautions, there should not be any hesitation for upper calyceal puncture in indicated patients.
PMCID: PMC4310113  PMID: 25657540
Percutaneous nephrolithotomy; staghorn; supracostal puncture
4.  Percutaneous Nephroscopic Surgery 
Korean Journal of Urology  2010;51(5):298-307.
With the development of techniques for percutaneous access and equipment to disintegrate calculi, percutaneous nephroscopic surgery is currently used by many urologists and is the procedure of choice for the removal of large renal calculi and the management of diverticula, intrarenal strictures, and urothelial cancer. Although it is more invasive than shock wave lithotripsy and retrograde ureteroscopic surgery, percutaneous nephroscopic surgery has been successfully performed with high efficiency and low morbidity in difficult renal anatomies and patient conditions. These advantages of minimal invasiveness were rapidly perceived and applied to the management of ureteropelvic junction obstruction, calyceal diverticulum, infundibular stenosis, and urothelial cancer. The basic principle of endopyelotomy is a full-thickness incision of the narrow segment followed by prolonged stenting and drainage to allow regeneration of an adequate caliber ureter. The preferred technique for a calyceal diverticulum continues to be debated. Excellent long-term success has been reported with percutaneous, ureteroscopic, and laparoscopic techniques. Each approach is based on the location and size of the diverticulum. So far, percutaneous ablation of the calyceal diverticulum is the most established minimally invasive technique. Infundibular stenosis is an acquired condition usually associated with inflammation or stones. Reported series of percutaneously treated infundibular stenosis are few. In contrast with a calyceal diverticulum, infundibular stenosis is a more difficult entity to treat with only a 50-76% success rate by percutaneous techniques. Currently, percutaneous nephroscopic resection of transitional cell carcinoma in the renal calyx can be applied in indicated cases.
PMCID: PMC2873882  PMID: 20495691
Diverticulum; Hydrocalycosis; Percutaneous nephrostomy; Transitional cell carcinoma; Urinary calculi
5.  Calyceal Diverticulum - a Mimic of Different Pathologies on Multiple Imaging Modalities 
Calyceal diverticula are outpouchings of a renal calyx. Often found incidentally on radiological imaging, they are generally benign and usually asymptomatic, although complications include infection and stone formation. More importantly, calyceal diverticula may mimic other potentially more serious pathology on imaging, such as renal tumour or abscess on ultrasound or computed tomography and even rib metastasis on bone scintigraphy. We present a case of a patient with a calyceal diverticulum found incidentally on imaging, in which the diverticulum is demonstrated on ultrasound, computed tomography, intravenous urogram and bone scintigraphy, and discuss the potential differential diagnoses that need to be excluded in this condition.
PMCID: PMC3558255  PMID: 23378883
Calyceal; diverticulum; renal calyx; IVU; intravenous urogram
6.  Clinical Manifestation of a Calyceal Diverticular Abscess in a Pregnant Woman 
Calyceal diverticula are congenital, nonsecretory abnormalities in which the transitional cell-lined cavity communicates with the renal collecting system. Here we present the case of a calyceal diverticular abscess during pregnancy. A 40-year-old primiparous woman developed the abscess at 23 weeks of gestation, with right flank pain and a 37.8°C fever. A transabdominal ultrasound revealed a 12 × 10 cm cystic mass in the right kidney. She was initially diagnosed with a simple renal cyst infection, and intravenous antibiotics were initiated. Percutaneous drainage was started at 26 weeks of gestation. When urine excretion from the cyst was confirmed by dye test using indigotindisulfonate sodium, the patient was diagnosed with a calyceal diverticular abscess. She gave birth to a 2,870 g healthy male at 38 weeks of gestation. Percutaneous drainage with low-dose antimicrobial therapy could thus allow for the continued pregnancy of women with a calyceal diverticular abscess until full term.
PMCID: PMC4265685  PMID: 25525537
7.  Percutaneous Endoscopic Holmium Laser Lithotripsy for Management of Complicated Biliary Calculi 
Background and Objectives:
Advances in endoscopic techniques have transformed the management of urolithiasis. We sought to evaluate the role of such urological interventions for the treatment of complex biliary calculi.
We conducted a retrospective review of all patients (n=9) undergoing percutaneous holmium laser lithotripsy for complicated biliary calculi over a 4-year period (12/2003 to 12/2007). All previously failed standard techniques include ERCP with sphincterotomy (n=6), PTHC (n=7), or both of these. Access to the biliary system was obtained via an existing percutaneous transhepatic catheter or T-tube tracts. Endoscopic holmium laser lithotripsy was performed via a flexible cystoscope or ureteroscope. Stone clearance was confirmed intra- and postoperatively. A percutaneous transhepatic drain was left indwelling for follow-up imaging.
Mean patient age was 65.6 years (range, 38 to 92). Total stone burden ranged from 1.7 cm to 5 cm. All 9 patients had stones located in the CBD, with 2 patients also having additional stones within the hepatic ducts. All 9 patients (100%) were visually stone-free after one endoscopic procedure. No major perioperative complications occurred. Mean length of stay was 2.4 days. At a mean radiological follow-up of 5.4 months (range, 0.5 to 21), no stone recurrence was noted.
Percutaneous endoscopic holmium laser lithotripsy is a minimally invasive alternative to open salvage surgery for complex biliary calculi refractory to standard approaches. This treatment is both safe and efficacious. Success depends on a multidisciplinary approach.
PMCID: PMC3015947  PMID: 19660213
Biliary calculi; Holmium laser; Endoscopic; Lithotripsy
8.  Flexible ureterorenoscopy: prospective analysis of the Guy's experience. 
OBJECTIVE: To report our outcomes with small diameter, actively deflectable flexible ureterorenoscopy from a prospective database. PATIENTS and METHODS: 114 flexible ureterorenoscopies were performed in 105 patients (mean age, 49.5 years; range, 19-85 years; 71 males, 34 females) over a 9-month period. Of these, 101 were for refractory stones following failed ESWL and 13 for diagnostic reasons. An Olympus URF P3 flexible ureteroscope with pressure irrigation was used. Electrohydraulic lithotripsy was used to fragment stones and the fragments were retrieved with Graspit, triradiate graspers or tipless baskets. RESULTS: Stents had previously been placed in 53% and dilatation of the ureteric orifice was necessary in 15%. In the stone group, the median operating time was 55 min (range, 15-210 min) and the median screening time 2.2 min (range, 0.3-9.1 min). Success was defined as complete stone clearance or good fragmentation to 2 mm or less. Overall success in this group was 72.3%. There was no statistically significant difference between lower and other calyces (P=0.83 Chi-square test). Successful outcome was achieved in 72% for stone size 10 mm or less, 80% for 11-20 mm and 50% for greater than 20 mm. Two or more procedures were needed in 8 patients. In the diagnostic group, the median operating time was 45 min (range, 20-60 min) and the median screening time 2 min (range, 0.3-8.3 min). The majority were for upper tract filling defects. Access and successful diagnosis was achieved in all cases. The major complication rate was 2.6%. The ureteroscope needed repair once during this series. CONCLUSIONS: Flexible ureterorenoscopy is an effective diagnostic and therapeutic tool in a select group of patients. It should be considered for ESWL-resistant upper tract stones but the results are poor in stones larger than 20 mm and percutaneous nephrolithotomy may be a better option in these patients.
PMCID: PMC1964230  PMID: 15333176
9.  Percutaneous nephrolithotomy for 1-2 cm lower-pole renal calculi 
The most appropriate management of patients with lower-pole calyceal (LC) stones remains controversial. In this review we discuss the role of percutaneous nephrolithotomy (PCNL) in the management of LC stones 1–2 cm in maximum dimension.
Materials and Methods:
A detailed literature review was performed to summarize the recent technical developments and controversies in PCNL. The results of PCNL for 1-2 cm LC calculi were reviewed.
PCNL is increasingly employed as a primary modality in the treatment of LC calculi. It has a high success rate and acceptably low percentage of major complications in experienced hands. Supine position is found to be as safe and effective as prone position. Urologist-acquired access is associated with fewer access-related complications and better stone-free rates. Ultrasound is increasingly employed as an imaging modality for obtaining access. There have been increasing reports of tubeless PCNL in the literature. Most patients undergoing tubeless PCNL do not need hemostatic agents as an adjuvant for hemostasis. Non-contrast computed tomography does not yield statistically valuable increase in the diagnosis of significant residual stones compared with that of plain X-ray and linear tomography. Comprehensive metabolic evaluation and aggressive medical management can control new stone recurrences and growth of residual fragments following PCNL.
PCNL is a highly effective procedure with consistently high stone-free rates when compared with extracorporeal shockwave lithotripsy or retrograde intrarenal surgery. The results also do not depend on anatomic factors and stone size. It is associated with low morbidity in experienced hands.
PMCID: PMC2684377  PMID: 19468514
Complications; lower calyx; management; percutaneous nephrolithotomy; renal calculi; technique
10.  Calyceal Diverticulum of the Kidney – Diagnostic Imaging Dilemma in Pediatric Patients – Case Report 
Calyceal diverticula are rarely diagnosed in children. They can mimic other renal cystic lesions and correct diagnosis can be difficult to establish. Connection between fluid collection and collecting system confirmed by imaging studies is the key diagnostic finding.
Case Report
In this report we present a case of pediatric patient with calyceal diverticulum, with initial ultrasonographic diagnosis of simple renal cyst. Final diagnosis was established after extended diagnostics following infection of a fluid collection.
1. Differential diagnosis of well-circumscribed solitary renal fluid collections in children should include particularly: simple cyst, calyceal diverticulum and the first demonstration of ADPKD. 2. Diagnosis of calyceal diverticulum should be confirmed by contrast studies. 3. Standard management of calyceal diverticula in children includes ultrasonographic follow-up and conservative treatment and rarely requires surgical intervention.
PMCID: PMC4298278  PMID: 25610511
Child; Nephrology; Pediatrics; Radiology; Urology
11.  Percutaneous Management of Caliceal Diverticuli 
Journal of Endourology  2009;23(10):1723-1729.
Background and Purpose
Caliceal diverticula are rare congenital abnormalities that can become symptomatic if associated with a calculus or infection. We review percutaneous management of caliceal diverticula.
Pathogenesis, clinical evaluation, management options, and recommended follow-up for symptomatic caliceal diverticula are reviewed. We present our single-stage and prepercutaneous nephrolithotomy opacification techniques for the management of caliceal diverticula. This involves complete extraction of all stone particles and ablation of the diverticular cavity without infundibular identification or dilation. Comparison of outcomes between our current ablative technique and our previous dilation technique is evaluated.
Percutaneous management of caliceal diverticula offers the highest symptomatic relief and stone-free rate of available management options. We identified 106 patients with caliceal diverticula who were treated with a percutaneous approach. Review of 85 of these patients demonstrated that most procedures can be performed with a small nephrostomy tube in place for 24 hours and an overnight hospital stay. Minimal complication and stone recurrence rates were observed. Patients treated with caliceal diverticular ablation experienced a shorter hospital stay, fewer complications, and a higher stone-free status than those patients who were treated with dilation of the diverticular infundibulum.
Percutaneous management of caliceal diverticula using cavity ablation is a minimally invasive technique that offers long-term symptomatic relief with minimal complications.
PMCID: PMC3744839  PMID: 19814580
12.  Laparoscopic Wedge Resection and Partial Nephrectomy - The Washington University Experience and Review of the Literature 
Open partial nephrectomy is an accepted form of treatment for a variety of benign conditions and for localized renal cell carcinoma. To date, there is limited experience with the clinical application of laparoscopic partial nephrectomy and wedge resection for benign and malignant disease of the kidney. Herein, we report our clinical experience with laparoscopic partial nephrectomy and a review of the current literature.
Twelve patients (27 - 81 years) have undergone laparoscopic wedge resection (3) or attempted polar partial nephrectomy (9) since 1993. In the group of 12 patients, 5 had a mass suspicious for a malignancy, 4 patients had symptomatic polar calyceal dilation with or without stone disease, and 3 patients had an atrophic or hydronephrotic upper pole moiety.
Among the patients in the polar nephrectomy group, a third were converted to an open procedure. The remaining 6 patients had a mean operative time of 6.5 hours (5.7 - 8.3 hours). These patients resumed their oral intake on average 0.8 days postoperatively. In the 2 patients with a mass, the final pathology was oncocytoma (1), and xanthogranulomatous reaction in a renal cyst (1). Postoperative complications included a nephrocutaneous fistula which was endoscopically fulgurated, a retroperitoneal urinoma which was percutaneously drained, and a two-day bout of ileus. The mean hospital stay was 5.3 days (2-9). Their full convalescence was completed in a mean of 4.2 weeks (2 - 8).
Three patients underwent a wedge resection for a superficial < 2 cm mass. The average operative time in this group was 3.5 hours (2 - 5.4). The mean time to resuming oral intake was 0.7 days (0.3 - 0.7). The final pathology was oncocytoma (1), oncocytic renal cell cancer (1), and old infarction (1); none of the patients had any complications. The mean hospital stay was 2.7 days (2- 4). Convalescence was completed in 4 weeks (range 1-8).
Laparoscopic wedge resection and polar partial nephrectomy are feasible, albeit currently tedious techniques. While wedge excision of a < 2 cm superficial lesion is relatively straightforward and efficient, laparoscopic polar partial nephrectomy remains a difficult technique and at present remains in evolution. Further development of instrumentation to provide for a reliable, expeditious, and hemostatic partial nephrectomy is needed.
PMCID: PMC3015259  PMID: 9876705
Partial nephrectomy; Laparoscopy; Kidney tumor
13.  The imaging appearances of calyceal diverticula complicated by uroliathasis 
The British Journal of Radiology  2010;83(994):888-894.
The presence of diverticula arising from the calyceal system is a relatively uncommon urological problem, occurring with an incidence of 2.1-4.5 per 1000 intravenous urogram (IVU) examinations. While the incidence of calyceal diverticula is low, the frequency of stone formation within them is high. We describe the aetiology and clinical presentation and describe the role of imaging with ultrasound, intravenous and retrograde pyelography and CT in diagnosis and planning treatment. We also describe the potential of fluid-sensitive magnetic resonance imaging techniques as a radiation-free alternative to the use of more conventional modalities, such as intravenous urography and retrograde pyelography, in delineating the anatomy of calyceal diverticula before surgical and radiological intervention especially in young patients and pregnant women.
PMCID: PMC3473751  PMID: 20846986
14.  Percutaneous nephrolithotomy in horseshoe Kidneys: is rigid nephroscopy sufficient tool for complete clearance? a case series study 
BMC Urology  2009;9:17.
this study represents a case series to evaluate how successful is the rigid percutaneous nephroscopy as a tool for clearance of all stones in various locations in horseshoe kidneys.
Between 2005 and 2009, we carried out PCNL (percutaneous nephrolithotomy) for calculi in horseshoe kidneys in 21 renal units (17 patients) in our department. The indications were large stone burden in 18 units and failed SWL(shock wave lithotripsy) in 3 renal units. All procedures were done under general anesthesia; using fluoroscopic guidance for localization and standard alkan dilatation followed by rigid nephroscopy and stone extraction with or without stone disintegration. We analyzed our results regarding the site and number of the required access, the intra and postoperative complications, the presence of any residual stones, as well as their location.
The procedure was completed, using a single access tract in 20 renal units, with the site of puncture being the upper calyx in nine units and the posterior middle calyx in eleven units. Only in one renal unit, two access tracts (an upper and a lower calyceal) were required for completion and a supracostal puncture was required in another case. There was no significant intraoperative bleeding and no blood transfusion was required in any patient. A pelvic perforation occurred in one case, requiring longer PCN (percutaneous nephrostomy) drainage. One patient with infection stones suffered urosepsis postoperatively which was successfully managed. Three cases had residual stones, all located in the renal isthmus, all residuals were un approachable with the rigid instrument; resulting in a overall stone-free rate of 85.7% at discharge.
Percutaneous nephrolithotomy is generally safe and successful in the management of stones in horseshoe kidneys. However, location of the stones in these patients is crucial to decide the proper tool for optimal stone clearance result.
PMCID: PMC2785831  PMID: 19917111
15.  Diverticulum of a Meckel's diverticulum containing a stone. 
Postgraduate Medical Journal  1991;67(789):692-694.
An 18 year old girl presented with acute abdominal pain and a calcified opacity in the pelvis. She proved to have a Meckel's diverticulum which had a secondary diverticulum at its apex, containing a stone. Meckel's stones are uncommon and diverticula of a Meckel's diverticulum exceedingly rare. This is only the second recorded case of such a diverticulum containing a stone, and the first to describe a calcified stone in this location.
PMCID: PMC2399063  PMID: 1924063
16.  Seoul National University Renal Stone Complexity Score for Predicting Stone-Free Rate after Percutaneous Nephrolithotomy 
PLoS ONE  2013;8(6):e65888.
Currently, no standardized method is available to predict success rate after percutaneous nephrolithotomy. We devised and validated the Seoul National University Renal Stone Complexity (S-ReSC) scoring system for predicting the stone-free rate after single-tract percutaneous nephrolithotomy (sPCNL).
Patients and Methods
The data of 155 consecutive patients who underwent sPCNL were retrospectively analyzed. Preoperative computed tomography images were reviewed. The S-ReSC score was assigned from 1 to 9 based on the number of sites involved in the renal pelvis (#1), superior and inferior major calyceal groups (#2–3), and anterior and posterior minor calyceal groups of the superior (#4–5), middle (#6–7), and inferior calyx (#8–9). The inter- and intra-observer agreements were accessed using the weighted kappa (κ). The stone-free rate and complication rate were evaluated according to the S-ReSC score. The predictive accuracy of the S-ReSC score was assessed using the area under the receiver operating characteristic curve (AUC).
The overall SFR was 72.3%. The mean S-ReSC score was 3.15±2.1. The weighted kappas for the inter- and intra-observer agreements were 0.832 and 0.982, respectively. The SFRs in low (1 and 2), medium (3 and 4), and high (5 or higher) S-ReSC scores were 96.0%, 69.0%, and 28.9%, respectively (p<0.001). The predictive accuracy was very high (AUC 0.860). After adjusting for other variables, the S-ReSC score was still a significant predictor of the SFR by multiple logistic regression. The complication rates were increased to low (18.7%), medium (28.6%), and high (34.2%) (p = 0.166).
The S-ReSC scoring system is easy to use and reproducible. This score accurately predicts the stone-free rate after sPCNL. Furthermore, this score represents the complexity of surgery.
PMCID: PMC3688830  PMID: 23824752
17.  Retrograde intrarenal surgery for lower pole renal calculi smaller than one centimeter 
Recently there has been an increasing interest in the application of retrograde intrarenal surgery (RIRS) for managing renal calculi. In this review we discuss its application for the management of lower calyceal (LC) stones less than 10 mm in maximum dimension.
Materials and Methods:
Literature was reviewed to summarize the technical development in flexible ureterorenoscopy and its accessories. Further, the indications, outcome and limitations of RIRS for LC calculi < 1 cm were reviewed.
Use of access sheath and displacement of LC stone to a more favorable location is increasingly employed during RIRS. Patients who are anticoagulated or obese; those with adverse stone composition and those with concomitant ureteral calculi are ideally suited for RIRS. It is used as a salvage therapy for shock wave lithotripsy (SWL) refractory calculi but with a lower success rate (46-62%). It is also increasingly being used as a primary modality for treating LC calculi, with a stone-free rate ranging from 50-90.9%. However, the criteria for defining stone-free status are not uniform in the literature. The impact of intrarenal anatomy on stone-free rates after RIRS is unclear; however, unfavorable lower calyceal anatomy may hamper the efficacy of the procedure. The durability of flexible ureteroscopes remains an important issue.
RIRS continues to undergo significant advancements and is emerging as a first-line procedure for challenging stone cases. The treatment of choice for LC calculi < 1 cm depends on patient's preference and the individual surgeon's preference and level of expertise.
PMCID: PMC2684415  PMID: 19468515
Flexible ureteroscopy; holmium laser lithotripsy; lower calyx; management; renal calculi; retrograde intrarenal surgery
18.  Kidney Access Device 
Percutaneous nephrolithotomy is the most complicated stone surgery technique to learn. The steep learning curve is related mainly to obtaining precise renal access by puncturing the targeted calyx. A minimally misaligned puncture may lead to torrential bleeding, failure of the surgery, and complications. Renal puncture can take a long time, and the increased fluoroscopic time is a hazard for the patient and surgeon.
To aid in renal puncture and overcome the learning curve associated with learning the renal puncture technique, we designed a kidney access device (KAD), which helps align the 3-dimensional targeted calyx under fluoroscopy for precise needle placement. The KAD allows access to calyces at all angles. A 3-step puncture technique was formulated for puncturing the kidney using the KAD in a porcine model (with comparable renal size and anatomy with humans). To evaluate the practicality of the KAD and its possible advantages and limitations, the KAD was used to puncture 3 targeted calyces of bilateral kidneys in 4 pigs. Guidewires were inserted into the renal collecting system through the placed needle.
Mean time per puncture was 4 ± 2 minutes (n = 24). Necropsy showed no retroperitoneal hematoma, visceral organ injury, or active bleeding from kidneys in any of the pigs. Kidneys were dissected and precise intrarenal placements of guidewires in relation to targeted calyces were noted at all 24 sites.
The KAD with the 3-step technique aids in the safe and accurate renal puncture, even in novice hands, while drastically reducing operative and fluoroscopy time. The KAD may also be used to access other organs and has potential applications in minimally invasive surgery.
PMCID: PMC4254481  PMID: 25489217
PCNL; Percutaneous nephrolithotomy; Kidney puncture; Kidney puncture device; Renal puncture
19.  Safety and efficacy of percutaneous nephrolithotomy for the treatment of paediatric urolithiasis 
Paediatric percutaneous nephrolithotomy (PCNL) has revolutionised the treatment of paediatric nephrolithiasis. Paediatric PCNL has been performed using both adult and paediatric instruments. Stone clearance rates and complications vary according to the technique used and surgeon experience. We present our experience with PCNL using adult instruments and a 28Fr access tract for large renal calculi in children under 18 years.
All patients undergoing PCNL at our institution between 2000 and 2009 were reviewed. Demographics, surgical details and post-operative follow-up information were obtained to identify stone clearance rates and complications.
PCNL was performed in 32 renal units in 31 patients (mean age: 10.8 years). The mean stone diameter was 19mm (range: 5–40mm). Twenty-six cases required single puncture and six required multiple tracts. Overall, 11 staghorn stones, 10 multiple calyceal stones and 11 single stones were treated. Twenty-seven patients (84%) were completely stone free following initial PCNL. Two cases had extracorporeal shock wave lithotripsy for residual fragments, giving an overall stone free rate of 91% following treatment. There was no significant bleeding or sepsis encountered either during the operation or in the post-operative setting. No patient required or received a blood transfusion.
Paediatric PCNL can be performed safely with minimal morbidity using adult instruments for large stone burden, enabling rapid and complete stone clearance.
PMCID: PMC3954287  PMID: 23131231
Percutaneous nephrolithotomy; Stones; Complications; Paediatrics
20.  In-Vitro Assessment of a New Portable Ballistic Lithotripter with Percutaneous and Ureteroscopic Models 
Journal of Endourology  2012;26(11):1500-1505.
Background and Purpose
The EMS Swiss LithoBreaker is a new, portable, electrokinetic lithotripter. We compared its tip velocity and displacement characteristics with a handheld, pneumatic lithotripter LMA StoneBreaker.™ We also evaluated fragmentation efficiency using in vitro models of percutaneous and ureteroscopic stone fragmentation.
Materials and Methods
Displacement and velocity profiles were measured for 1-mm and 2-mm probes using a laser beam aimed at a photo detector. For the percutaneous model, 2-mm probes fragmented 10-mm spherical BegoStone phantoms until the fragments passed through a 4-mm mesh sieve. The ureteroscopic model used 1-mm probes and compared the pneumatic and electrokinetic devices to a 200-μm holmium laser fiber. Cylindrical (4-mm diameter, 4-mm length) BegoStone phantoms were placed into silicone tubing to simulate the ureter; fragmented stones passed through a narrowing in the tubing.
For both 1-mm and 2-mm probes, the electrokinetic device had significantly higher tip displacement and slower tip velocity, P<0.01. In the percutaneous model, the electrokinetic device needed an average of 484 impulses over 430 seconds to fragment one BegoStone, while the pneumatic device needed 29 impulses over 122 seconds to fragment one stone. Both clearance times and number of impulses needed for percutaneous stone clearance were significantly different at P<0.01. Ureteroscopically, the mean clearance time was 97 seconds for the electrokinetic lithotripter, 145 seconds for the pneumatic lithotripter, and 304 seconds for the laser. Comparing the pneumatic device with the electrokinetic device ureteroscopically, there was no significant difference in clearance time, P=0.55. Both the pneumatic and electrokinetic lithotripters, however, demonstrated decreased clearance times compared with the laser, P=0.027.
The portable electrokinetic lithotripter may be better suited for ureteroscopy instead of percutaneous nephrolithotomy. It appears to be comparable to the portable pneumatic device in the ureter. Further clinical studies are needed to confirm these findings in vivo.
PMCID: PMC3613175  PMID: 22873666
21.  A Novel Technique of Ultra-Mini-Percutaneous Nephrolithotomy: Introduction and an Initial Experience for Treatment of Upper Urinary Calculi Less Than 2 cm 
BioMed Research International  2013;2013:490793.
Objectives. To describe our novel modified technique of ultra-mini-percutaneous nephrolithotomy (UMP) using of a novel 6 Fr mininephroscope through an 11–13 Fr metal sheath to perform holmium: YAG laser lithotripsy. Methods. The medical records of 36 patients with moderate-sized (<20 mm) kidney stones treated with UMP from April to July 2012 were retrospectively reviewed. Patients were assessed at the 1st day and 1st month postoperatively by KUB and US to assess stone-free status. Results. The mean stone size was 14.9 ± 4.1 mm (rang: 6–20). The average operative time was 59.8 ± 15.9 (30–90) min. The stone-free rate at postoperative 1st day and 1st month was 88.9% and 97.2%. The mean hospital stay was 3.0 ± 0.9 (2–5) days. Complications were noted in 6 (16.7%) cases according to the Clavien classification, including sepsis in 2 (5.6%) cases (grade II), urinary extravasations in 1 (2.8%) case (grade IIIa), and fever in 3 (8.3%) cases (grade II). No patients needed blood transfusion. Conclusions. UMP is technically feasible, safe, and efficacious for moderate-sized renal stones with an advantage of high stone-free rates and low complication rates. However, due to the limits of its current unexplored indications, UMP is therefore a supplement to, not a substitute for, the standard mini-PCNL technology.
PMCID: PMC3741699  PMID: 23984372
22.  Combined Minimally Invasive Percutaneous Nephrolithotomy and Retrograde Intrarenal Surgery for Staghorn Calculi in Patients with Solitary Kidney 
PLoS ONE  2012;7(10):e48435.
To present our experience with simultaneous combined minimally invasive percutaneous nephrolithotomy (MPCNL) and retrograde intrarenal surgery (RIRS) to manage patients with staghorn calculi in solitary kidney, and evaluate the safety, efficiency and feasibility of this approach.
Methodology/Principal Findings
The study included 20 patients with staghorn calculi in solitary kidney. Demographic characteristics, stone location and surface area were recorded. After informed consent, the patients underwent one stage MPCNL firstly. Combined second stage MPCNL and RIRS simultaneously were performed at postoperative 5–7 days. Operative parameters, stone-free rate (SFR), stone analyses and complications were evaluated. Serum creatinine (Scr), glomerular filtration rate (GFR) and chronic kidney disease (CKD) were measured preoperatively, postoperatively at 1 month, and each follow-up visit. All patients had staghorn stones involving multiple calyces. The mean stone burden was 1099.9±843.95 mm2. All patients had only one percutaneous access tract. The mean whole operative duration was 154.37±32.45 min. The mean blood loss was 64 (12–140) ml. The final SFR was 90%. During the 1-month follow-up study period, four patients improved in CKD stage. Two patients who had CKD (stage 5) still needed dialysis postoperatively. Mean Scr of the rest patients preoperatively was 187.16±94.12 compared to 140.99±57.92 umol/L by the end of 1-month follow-up period (p = 0.019). The same findings were observed in GFR in that preoperatively it was 43.80±24.74 ml/min and by the end of the 1-month follow-up it was 49.55±21.18 ml/min (p = 0.05).
Combined MPCNL and RIRS management effectively decrease the number and size of percutaneous access tracts, which is safe, feasible, and efficient for managing staghorn calculi in solitary kidney with satisfactory SFR and reducing blood loss, potential morbidity associated with multiple tracts. The approach did not adversely affect renal function at both short-term and long-term follow-up.
PMCID: PMC3484138  PMID: 23119016
23.  The feasibility of shockwave lithotripsy for treating solitary, lower calyceal stones over 1 cm in size 
Recently, few studies were reported about the treatment of large, solitary, renal calculi between shockwave lithotripsy (SWL) and percutaneous nephrolithotomy (PNL). We assess the feasibility of SWL for managing solitary, lower calyceal stones over 1 cm by comparing the results of lower pole calculi treatment between patients that underwent SWL or PNL.
We retrospectively reviewed clinical data for patients who had undergone PNL or SWL due to lower calyceal stones over 1 cm. Group 1 consisted of patients who underwent SWL to treat lower pole renal calculi from 2010 to 2011. Group 2 included patients who underwent PNL to manage lower pole renal calculi from 2008 to 2009. We compared patient age, gender, stone size, comorbidities, postoperative complications, additional interventions and anatomical parameters between the two groups.
A total of 55 patients were enrolled in this study. The mean ages (±SD) of groups 1 (n = 33) and 2 (n = 22) were 55.1 (±13.0) and 50.0 (±10.6) years (p = 0.133) and mean stone sizes were 1.6 (±0.7) and 1.9 (±0.8) cm (p = 0.135), respectively. There were no significant differences in gender distribution, comorbidities or stone laterality between the two groups. No significant differences in various parameters were observed between patients with stones 1 to 2 cm and ones with stones 2 cm or larger.
Our results demonstrated that SWL is a safe, feasible treatment for solitary, lower calyceal stones over 1 cm.
PMCID: PMC3612404  PMID: 23589749
24.  Predicting calyceal access for percutaneous nephrolithotomy with computed tomography multiplanar reconstruction 
Clinics  2013;68(6):892-895.
Objective parameters in computed tomography (CT) scans that could predict calyceal access during percutaneous nephrolithotomy have not been evaluated. These parameters could improve access planning for percutaneous nephrolithotomy. We aimed to determine which parameters extracted from a preoperative multiplanar reconstructed CT could predict renal calyceal access during a percutaneous nephrolithotomy.
From January 2009 through April 2011, 230 patients underwent 284 percutaneous nephrolithotomies at our institution. Sixteen patients presented with complete staghorn calculi, and 11 patients (13 renal units) were analyzed. Five parameters were extracted from a preoperative reconstructed CT and compared with the surgical results of percutaneous nephrolithotomy.
Fifty-eight calyces were studied, with an average of 4.4 calyces per procedure. A rigid nephroscope was used to access a particular calyx, and a univariate analysis showed that the entrance calyx had a smaller length (2.7 vs. 3.98 cm, p = 0.018). The particular calyx to be accessed should have a smaller length (2.22 vs. 3.19 cm, p = 0.012), larger angles (117.6 vs. 67.96, p<0.001) and larger infundibula (0.86 vs. 0.61 cm, p = 0.002). In the multivariate analysis, the only independent predictive factor for accessing a particular calyx was the angle between the entrance calyx and the calyx to be reached (OR 1.15, 95% confidence interval [CI], 1.053–1.256, p = 0.002).
The angle between calyces obtained by multiplanar CT reconstruction is the only predictor of calyx access.
PMCID: PMC3674302  PMID: 23778484
Computed Tomography; Kidney; Percutaneous Nephrolithotomy; Urinary Calculi
25.  A modified Rendezvous ERCP technique in duodenal diverticulum 
AIM: To postoperative endoscopic retrograde cholangiopancreatography (ERCP) failure, we describe a modified Rendezvous technique for an ERCP in patients operated on for common bile duct stone (CBDS) having a T-tube with retained CBDSs.
METHODS: Five cases operated on for CBDSs and having retained stones with a T-tube were referred from other hospitals located in or around Istanbul city to the ERCP unit at the Haydarpasa Numune Education and Research Hospital. Under sedation anesthesia, a sterile guide-wire was inserted via the T-tube into the common bile duct (CBD) then to the papilla. A guide-wire was held by a loop snare and removed through the mouth. The guide-wire was inserted into the sphincterotome via the duodenoscope from the tip to the handle. The duodenoscope was inserted down to the duodenum with a sphincterotome and a guide-wire in the working channel. With the guidance of a guide-wire, the ERCP and sphincterotomy were successfully performed, the guide-wire was removed from the T-tube, the stones were removed and the CBD was reexamined for retained stones by contrast.
RESULTS: An ERCP can be used either preoperatively or postoperatively. Although the success rate in an isolated ERCP treatment ranges from up to 87%-97%, 5%-10% of the patients require two or more ERCP treatments. If a secondary ERCP fails, the clinicians must be ready for a laparoscopic or open exploration. A duodenal diverticulum is one of the most common failures in an ERCP, especially in patients with an intradiverticular papilla. For this small group of patients, an antegrade cannulation via a T-tube can improve the success rate up to nearly 100%.
CONCLUSION: The modified Rendezvous technique is a very easy method and increases the success of postoperative ERCP, especially in patients with large duodenal diverticula and with intradiverticular papilla.
PMCID: PMC3831199  PMID: 24255749
Endoscopic retrograde cholangiopancreatography; Retained stones; Antegrade cannulation; Intradiverticular papilla; T-tube

Results 1-25 (207078)