Larger Stone Size Research Articles

Transurethral cystolithotripsy with a novel special endoscope

To evaluate the safety and efficiency of the Aihua (AH)-1 stone removal system (SRS) to treat bladder stones. Thirty five patients with of bladder stones >2cm and with benign prostatic hyperplasia were treated by transurethral cystolithotripsy with the SRS and TURP. The results in these patients were compared with 14 patients treated with current devices. In the SRS group, 26 patients had a single stone. Average stone size was 3.34±1.03cm, total operating time was 55.12±19.95min, and stone removal time was 23.30±17.08min. In the control group, 12 patients had a single stone. The average stone size was 2.46±0.45cm (larger stone size in SRS group, P<0.05), total operating time was 79.85±24.63min (shorter operating time in SRS group, P<0.05) and stone removal time was 43.28±24.18min the control group (shorter removal time in SRS group, P<0.05). Mean stone size was 2.37±1.18cm and mean time to remove one stone was 12.57±12.99min in the SRS group. Mean stone size was 2.40±0.48cm (no significant difference between groups, P>0.05) and mean time to remove one stone was 33.23±25.26min in the control group (shorter time in the SRA group, P<0.001). No significant complication was found in the SRS group. This study suggests that multiple functions of SRS can be expected in transurethral cystolithotripsy. It can be used to fix stones during lithotripsy, and automatically collect stones and extract more stones through the sheath at one time during lithoextraction, which can reduce surgical time and damage to the bladder and urethra. This surgical procedure appears to be safe and efficient, and operating indications for transurethral cystolithotripsy could be expanded with this surgical procedure.

Giant choledocholithiasis treated by mechanical lithotripsy using a gastric bezoar basket.

Mechanical lithotripsy (ML) is usually considered as a standard treatment option for large bile duct stones. However, it is impossible to retrieve oversized stones because the conventional lithotripsy basket may not be able to grasp the stone. However, there is no established endoscopic extraction method for such giant stone removal. We describe a case of successful extraction of a 4-cm large stone using a gastric bezoar basket. A 78-year-old woman had suffered from upper abdominal pain for 20 d. Contrast-enhanced computed tomogram revealed a 4-cm single stone in the distal common bile duct (CBD). Endoscopic stone retraction was decided upon and endoscopic papillary balloon dilation was performed using a large balloon. An attempt to capture the stone using a standard lithotripsy basket failed due to the large stone size. Subsequently, we used a gastric bezoar basket to successfully capture the stone. The stone was fragmented into small pieces and extracted. The stone was completely removed after two sessions of endoscopic retrograde cholangiopancreatography; each of which took 30 min. No complications occurred during or after the procedure. The patient was fully recovered and discharged on day 11 of hospitalization. ML using a gastric bezoar basket is a safe and effective retrieval method in select cases, and is considered as an alternative nonoperative option for the management of difficult CBD stones.

The relationship between ureteral stone characteristics and secondary signs in renal colic

PurposeTo assess correlations between stone size/location and severity of secondary signs for ureteral obstruction. MethodsUnenhanced multi-detector computed tomography examinations of 150 patients with acute renal colic were reviewed. Stone size, location in the ureter, kidney size and Hounsfield unit values, perinephric edema, and degree of hydronephrosis were assessed. ResultsPale kidney sign was detected in 36%. Hydronephrosis was mild in 63% and severe in 21%; severe hydronephrosis was associated with larger stones. Mid-ureter and ureteropelvic junction stones were more likely to cause hydronephrosis. Perinephric edema (56%) was not correlated with stone size/location. ConclusionOnly severe hydronephrosis was significantly associated with larger stone size.

Risk reduction strategy for radiation exposure during percutaneous nephrolithotomy

To discuss the risk of radiation exposure to patients with nephrolithiasis. To review the risk factors for increased radiation exposure to patients during percutaneous nephrolithotomy (PNL) from fluoroscopy. To review the techniques to reduce patient radiation doses during PNL. Patients with nephrolithiasis are at risk for significant radiation exposure from diagnostic imaging. Fluoroscopy used during surgical treatment of nephrolithiasis also contributes to patient radiation exposure. On average, PNL with fluoroscopy exposes patients to more radiation than a noncontrast computed tomography of the abdomen and pelvis. Risk factors for increased radiation during PNL include obesity, larger stone size and increased access tracts. Following the principles of As Low As Reasonably Achievable, use of air instead of contrast for retrograde pyelogram and use of ultrasound all reduce radiation exposure during PNL. It is important to be aware of the amount of radiation patients with nephrolithiasis receive. These patients are at risk for multiple imaging studies and multiple procedures during their lifetime. Whenever possible, the techniques outlined in this review should be implemented to reduce the amount of radiation to which patients are exposed during PNL.

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.

Acute Postoperative Pain after Ureteroscopic Removal of Stone: Incidence and Risk Factors

PurposeUreteroscopic removal of stones (URS) has been widely used to treat ureteral stones because it is comparatively safe, has a high success rate, and enables patients to rapidly return to their daily routines. However, some patients experience pain after URS, but the incidence of acute post-URS pain remains largely unknown. This study aimed to investigate the incidence of acute postoperative pain after URS and the associated risk factors.Materials and MethodsData for 143 consecutive patients who underwent URS from June 2008 to December 2010 were collected. After excluding 8 patients who developed intraoperative complications, the patients were divided into two groups according to postoperative pain on the first postoperative day. Acute postoperative pain was defined as a pain score greater than 4 on a visual analogue pain scale (normal range, 0 to 10). Various factors were analyzed to identify the risk factors that could predict acute postoperative pain after URS.ResultsThe stone-free rate without URS intraoperative complications was 95.5%. A total of 21 (14.6%) patients experienced postoperative pain on the first postoperative day. Young age, psychiatric illness, history of urinary tract infection, use of a stone basket, large stone size, and prolonged operation time were identified as risk factors for acute postoperative pain.ConclusionsThe incidence of acute postoperative pain is not that low and should not be overlooked, because it is associated with postoperative complications that could result in an unscheduled hospital admission or visit. Active pain control should be contemplated after URS in young patients and in those with a history of urinary tract infection, psychiatric illness, large stone size, and prolonged operation time.

Segmental Adenomyomatosis of Gallbladder: CT Assessment of the Patterns of Cholecystolithiasis

Purpose: To clarify the relationship between the pattern of cholecystolithiasis and the gross features of segmental adenomyomatosis of the gallbladder. Materials and Methods: Fifty-five consecutive patients with segmental adenomyomatosis with calcified gallbladder stones defined on CT were retrospectively analyzed in terms of (i) stone location (fundal vs. neck compartment) and (ii) size of the largest stone as a function of the extent of segmental mural thickening (type A, limited at the narrow segment; type B, partially extended in the fundal direction; type C, involving the entire fundal compartment). The extent of segmental mural thickening in patients with cholecystolithiasis was compared with a control group (n = 48) lacking stones. Results: Stones were found more frequently in the fundal compartment in 48 patients compared to the neck compartment in 12 patients (p<0.001). The mean size of the largest stone in type C (5.4 ± 4.9 mm) was larger than in type A (2.3 ± 2.2 mm) (p=0.033). In patients with cholecystolithiasis, type C segmental thickening was predominant (69%) compared to the control group (42%) (p=0.012). Conclusion: In addition to a higher prevalence of stones, a wide extent of mural thickening combined with large stone size in the fundal compartment suggests the contribution of segmental adenomyomatosis to stone formation and chronic inflammation.

Laparoscopic ureterolithotomy: minimally invasive second line treatment

To describe our experience of 33 laparoscopic ureterolithotomies for large ureteral stones. Since February 2004, in our department, 33 patients had undergone laparoscopic ureterolithotomy. Inclusion criteria were failure of SWL and\or ureteroscopic treatment. Stones were located in the lower ureter in 9 patients, in the mid ureter in 16 patients, and in the upper ureter in 8 patients. Mean age of the patients was 47 years (range 37-51). The mean stone size, at preoperative IVP, was 34 mm (range 18-55). All stones were impacted from 4 to 36 months before procedure. Successful rates were 100%. No conversion to open surgery occurred. No intraoperative and postoperative complications occurred. Mean operating time was 85 min (range 60-160). Mean intraoperative blood loss was 70 ml (range 30-120). Mean hospital stay was 3.4 days (range 2-7). Mean follow-up was 24 months (range 6-44). During follow-up, no major complications were observed in any patients. In our hand, first-line treatment after failure of SWL and\ or ureteroscopy is laparoscopic ureterolithotomy. Large stone size and previous open surgery did not affect the successful rates of laparoscopic ureterolithotomy.

A Prospective Randomized Study Comparing Shock Wave Lithotripsy and Semirigid Ureteroscopy for the Management of Proximal Ureteral Calculi

To conduct a prospective randomized study comparing both techniques for the management of solitary radio-opaque upper ureteral stones < 2 cm in diameter. The ideal treatment for upper ureteral stones > 1 cm size remains to be determined with shock wave lithotripsy (SWL) and ureteroscopy (URS) being acceptable options. A total of 200 patients were included in the study. They were randomized into 2 equal groups. Group A underwent in situ SWL as a primary therapy. Group B underwent URS, using semirigid URS with intracorporeal lithotripsy. Efficiency quotient (EQ), cost analysis, and predictors of failure were estimated for both techniques. For stones of size > or = 1 cm, the initial stone-free rate for URS and SWL was 88% and 60%, respectively. The estimated EQ was 0.79 and 0.43 for both techniques respectively. For stones < 1 cm, the initial stone-free rate for URS and SWL was 100% and 80%, respectively. The estimated EQ was 0.88 and 0.70 for both techniques, respectively. The mean cumulative costs were significantly more in SWL group (P <.05). Predictors of URS failure included; male gender, failure to pass guidewire beyond the stone, and extravasation. Predictors of SWL failure included large stone size > 1 cm, calcium oxalate monohydrate stone, and higher degrees of hydronephrosis. URS with intracorporeal lithotripsy is an acceptable treatment modality for all proximal ureteral calculi, particularly stones > 1 cm. SWL should remain the first-line therapy for proximal ureteral calculi < or = 1 cm because of the less invasive nature and lower anesthesia (i.v. sedation).

On the unusual characteristics of the diamonds from Letšeng-la-Terae kimberlites, Lesotho

The Letšeng-la-Terae kimberlites are situated 3100 m above sea level in the Maloti Mountains of Lesotho, southern Africa. The principal economic bodies are two Late Cretaceous, low grade, 1–3.5 carats/hundred ton (cpht), kimberlite pipes that host high-value diamonds realising US$ 2000–2500/carat ($/ct) in 2008 terms. Locally, the larger kimberlite body is referred to as the Main Pipe (17.2 ha) and the smaller one is called the Satellite Pipe (5.2 ha). These pipes, and their associated eluvial and proximal alluvial deposits, are renowned for yielding large, “D” colour, gem quality diamonds, including + 100 carat (ct) stones. Earlier artisanal effort (1959–1977) and formal mining (1977–1982) produced 335,000 carats (cts), including the 601 ct Lesotho Brown in 1968. In 2003, Letšeng Diamonds Limited re-commenced mining operations and had produced 265,000 cts by the end of July 2008, including 24 + 100 ct diamonds, the largest of which was the 603 ct Lesotho Promise. We report here on the unusual characteristics of the Letšeng diamond population that include: i. 75% gem quality that is more commonly associated with alluvial diamond deposits, ii. large average stone size of ca. 1 carat/stone (ct/stn) that is also more typical of certain alluvial diamond placers, iii. high-yielding, rounded to flattened irregular, resorbed dodecahedral shapes (Main Pipe 67% and Satellite Pipe 87%) with subordinate dodecahedral macle (Main Pipe 32% and Satellite Pipe 12%) and broken (ca. 1%) forms. In both pipes the octahedral component is virtually absent (< 0.1%), iv. economically favourable colour mix (ca. 33% white colour diamonds in both pipes), v. abundance of nitrogen-free, “D” colour, Type IIa diamonds that dominate the internationally recognised “special” stone size fraction which covers all diamonds larger than + 10.8 cts (Main Pipe 32% and Satellite Pipe 51%). During 2008, these larger, “special” diamonds commanded prices in excess of US$ 15,000/ct, contributing ca. 75% of the revenue generated by the Letšeng mine. Furthermore, of the 24 + 100 ct diamonds recovered between November 2003 and July 2008, 18 (75%) were Type IIa “D” colour diamonds that also fetched prices mostly in excess of US$ 25,000/ct. Therefore the Type IIa diamonds boost significantly the revenue per unit measure (in this case, the US$/ton) of the Letšeng-la-Terae pipes, making these low grade kimberlites economic to mine.

Scattered Radiation Doses to the Patients and Medical Practitioneer from Extracorporeal Shock Wave Lithotripsy

Purpose: We estimated scattered radiation doses to the patients and medical practitioneer and revealed risk factors associated with increasing radiation doses during extracorporeal shock wave lithotripsy (ESWL). Materials and Methods: At first, we measured radiation doses 2 times using thermoluminescence dosimeter to simulative patients and medical practitioneer without any shield during 10 minutes of ESWL and determined mean radiation dose/minute. From June to August 2007 at our institution, we prospectively measured radiation exposured time during respective ESWL for treatment of urinary stones. Thereafter, we calculated practical radiation doses to patients and medical practitioneer from respective mean radiation dose/minute. We also analyzed which factors were associated with increasing radiation doses. Results: A total of 50 ESWL were analyzed from 38 patients. Mean radiation dose/minute to simulative patients and medical practitioneer was 16.20, 0.006mSv respectively. At 1 time ESWL, median radiation exposured time was 360 seconds (130-980), therefore, median radiation dose to patients and medical practitioneer was calculated as 97.20mSv (35.10-264.60), and 0.04mSv (0.01-0.08) respectively. Larger stone size had a correlation with increasing radiation dose and additional pain control group had higher radiation dose than otherwise. Conclusions: During ESWL, patients were relatively exposed to high radiation which were roughly corresponded to that of 3 times of computed tomography. But the radiation dose to medical practitioneer was insignificant consider international guideline. Medical practitioneer should be aware of radiation hazard and try to minimize radiation dose to the patients at the time of ESWL. (Korean J Urol 2008;49:155-159) 󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏󰠏

Sphinterotomy Plus Large Balloon Papillary Dilatation for Large Bile Duct Stones

Backgraound: One of the main problems in removing CBD stone is large stone size (>15 mm). It requires prolonged time and repeated procedure to remove large CBD stone. And there is higher risk of bleeding during wide EST. The aim of this study was to determine the utility of paillary dilatation with large balloon after EST. Method: Seventy patients with large (>15 mm) CBD stone were enrolled for this study. The patients underwent papillary dilatation with a 15 mm or 20 mm diameter balloon after EST (mid-incisoin). Then, stones were extracted by basket. And additional mechanical lithotripsy was done when stone removal was unsuccessful. Result: The maximum stone diameter was 21.5 mm. Average number of stones was 1.4. Periampullary diverticulum was found in 16 patient. Complete stone removal was achieved in all patient. We used 15 mm balloon in 25 patient, 20 mm balloon in 45 patient. And we needed mechanical lithotripsy in 11 patients in whom stone removal was unsuccessful by basket extraction. After the procedure, the serum amylase and/or lipase levels were elevated in 9 patients (12%). But, true pancreatitis was noted in only three patient (4%). Minor bleeding was encountered in 10 patients (14%) and was controlled spontaneously or by balloon compression. There was no critical complication such as perforation, severe pancreatitis, active bleeding or death. Conclusion: Large balloon papillary dilatation after EST is safe and effective method for treatment of large CBD stones. And this method can reduce the procedure time or repeated ERCP.

Biliary sphincterotomy plus dilation with a large balloon for bile duct stones that are difficult to extract

Bile duct stones are still present in 10% to 15% of patients after the application of conventional endoscopic extraction techniques and require additional procedures for duct clearance. In the vast majority of these cases, there are 2 main problems: large stone size (>15 mm) and tapering of distal bile duct. Fifty-eight patients in whom endoscopic sphincterotomy and standard basket/balloon extraction were unsuccessful in the removal of bile duct stones underwent dilation with a 10- to 20-mm diameter (esophageal/pyloric type) balloon at the same session. In 18 patients with tapered distal bile ducts (Group 1), 12- to 18-mm diameter balloon catheters were used to enlarge the orifice. In 40 patients with square, barrel shaped and/or large (>15mm) stones (Group 2), the sphincterotomy orifice was enlarged with 15- to 20-mm diameter balloon catheters. After dilatation, standard basket/balloon extraction techniques were used to remove the stone(s). Stone clearance was successful in 16 patients (89%) in Group 1 and 35 (95%) in Group 2. Complications occurred in 9 (15.5%) patients. Dilation with a large-diameter balloon after endoscopic sphincterotomy is a useful alternative technique in patients with bile duct stones that are difficult to remove with standard methods.

Comparison of outcomes of ureteroscopy for ureteral calculi located above and below the pelvic brim

Objectives. To compare the safety and efficacy of ureteroscopy performed for proximal and distal ureteral calculi in a contemporary cohort. Ureteroscopy has been used most often for distal ureteral calculi. However, advances in endoscopic equipment have facilitated access to the proximal urinary tract and have broadened the indications for ureteroscopy. Methods. One hundred ninety-one patients underwent rigid and/or flexible ureteroscopy for ureteral calculi at the University of Michigan between January 1, 1997 and September 30, 1999. Only 7 patients with either bilateral calculi or steinstrasse were excluded. The final cohort consisted of 184 patients who underwent ureteroscopy for distal stones (n = 103) or middle/upper ureteral stones (n = 81). Results. Bivariate analyses of pretreatment and perioperative characteristics were used to assess the sample population. The initial success rate for the distal and proximal ureteral calculi was 96% and 78%, respectively ( P = 0.0008). After a “second-look” procedure in 4 and 7 patients with distal and proximal calculi, respectively, the success rate improved to 99% and 88%, respectively ( P = 0.004). No differences were noted between groups regarding the intraoperative ( P = 0.51) or postoperative ( P = 0.85) complication rates. Multivariate logistic regression analysis confirmed that larger stone size (odds ratio 1.2, P = 0.0006) and proximal ureteral location (odds ratio 4.8, P = 0.01) are independent predictors of treatment failure. Conclusions. Ureteroscopic management of proximal and distal ureteral calculi is highly successful, and the difference in success rates has narrowed substantially. Currently, no greater risk is conferred to the patient for endoscopy of more proximal ureteral calculi.

Fluid characteristics of the diamondiferous Droogeveldt Gravels, Vaal Valley, South Africa

The Late Cretaceous to early Tertiary Droogeveldt gravels, one of the more famous alluvial diamond diggings in the Vaal basin of South Africa for both grade and large stone size, were totally exploited in the earlier part of this century. The best recoveries were obtained from high elevation (1,100- to 1,130-m elev) bimodal gravels situated in narrow (2- to 20-m wide), straight-sided, bedrock depressions <1 km long, some 5 to 10 km from the current Vaal River (1,000-m elev). These gravels, forming a fining-upward profile, comprise cobble to pebble, silica-rich clasts characteristic of the current Vaal drainage basin set among now-weathered bedrock boulders derived locally from the underlying Archean Ventersdorp volcanic rocks. The gravel-filled depressions, known by the early mining community as sluits, coincide with major structural lineaments in the Ventersdorp bedrock. Although the now rare, remnant weathered profiles resemble colluvium or debris flow-type deposits, the presence of potholed and smooth, polished, but irregular bedrock footwall in the sluits as well as rounded and percussion-scarred silica clasts points to a more energetic fluvial influence. The well-jointed bedrock sidewalls of the sluits provided readily accessible boulders (oversize clasts) to these gully-like features. Thus, the exceptional diamond concentrations and large stone size in the Droogeveldt gravels are attributed to a combination of primary, fixed turbulent zones formed by the narrow bedrock gullies with attendant pothole and scour trapsites, and secondary, quasi-fixed turbulent zones associated with the locally derived boulders (oversize clasts) in a paleo-Vaal River drainage. The sluits are not eroded kimberlite dikes and the bulk of their diamonds are likely to be sourced from the Cretaceous kimberlites in the greater Kimberley area.

The Role of Percutaneous Nephrolithotomy in the Management of Pediatric Renal Calculi

Purpose Minimally invasive techniques for the treatment of urinary calculi in children are recommended due to an increased probability of recurrence. Percutaneous nephrolithotomy is well established in adults but to our knowledge this procedure has not been reported previously in a large series of children. We review our experience with percutaneous nephrolithotomy in children. Materials and Methods From 1987 to 1995 percutaneous nephrolithotomy was performed in 25 children 3 to 16 years old (median age 8). Indications for percutaneous nephrolithotomy were an obstructed kidney in 10 cases, large stone size or staghorn calculus in 8, failed extracorporeal shock wave lithotripsy in 4 and residual stones after open surgery in 3. There were 15 solitary renal, 4 staghorn and 2 upper ureteral stones, and 5 children had multiple renal calculi. Results Percutaneous nephrolithotomy was performed once in 22 patients, and 2, 3 or 5 times in the remainder. Of the 25 patients 17 (68%) were stone-free at hospital discharge or shortly thereafter following a single session of percutaneous nephrolithotomy. Retained calculi after a single percutaneous nephrolithotomy treatment were much more common with staghorn stones (2 of 4 cases or 50%) and multiple stones (3 of 5 or 60%) compared to solitary renal stones (2 of 15 or 13.3%). With subsequent extracorporeal shock wave lithotripsy or repeat percutaneous nephrolithotomy the stone clearance rate was as high as 92%. At a 2 to 66-month followup (average 23) no late complications were noted. Radioisotope scans available in 10 cases before and after percutaneous nephrolithotomy revealed unchanged differential function and evidence of significant renal scars in only 1. Conclusions Percutaneous nephrolithotomy is a suitable and safe procedure for treating renal stones in children.

The role of percutaneous nephrolithotomy in the management of pediatric renal calculi.

Minimally invasive techniques for the treatment of urinary calculi in children are recommended due to an increased probability of recurrence. Percutaneous nephrolithotomy is well established in adults but to our knowledge this procedure has not been reported previously in a large series of children. We review our experience with percutaneous nephrolithotomy in children. From 1987 to 1995 percutaneous nephrolithotomy was performed in 25 children 3 to 16 years old (median age 8). Indications for percutaneous nephrolithotomy were an obstructed kidney in 10 cases, large stone size or staghorn calculus in 8, failed extracorporeal shock wave lithotripsy in 4 and residual stones after open surgery in 3. There were 15 solitary renal, 4 staghorn and 2 upper ureteral stones, and 5 children had multiple renal calculi. Percutaneous nephrolithotomy was performed once in 22 patients, and 2, 3 or 5 times in the remainder. Of the 25 patients 17 (68%) were stone-free at hospital discharge or shortly thereafter following a single session of percutaneous nephrolithotomy. Retained calculi after a single percutaneous nephrolithotomy treatment were much more common with staghorn stones (2 of 4 cases or 50%) and multiple stones (3 of 5 or 60%) compared to solitary renal stones (2 of 15 or 13.3%). With subsequent extracorporeal shock wave lithotripsy or repeat percutaneous nephrolithotomy the stone clearance rate was as high as 92%. At a 2 to 66-month followup (average 23) no late complications were noted. Radioisotope scans available in 10 cases before and after percutaneous nephrolithotomy revealed unchanged differential function and evidence of significant renal scars in only 1. Percutaneous nephrolithotomy is a suitable and safe procedure for treating renal stones in children.

Endoscopic balloon sphincteroplasty (papillary dilation) for bile duct stones: Efficacy, safety, and follow-up in 100 patients

Background: Because sphincterotomy accounts for a major portion of the morbidity and mortality associated with ERCP, we have proposed endoscopic balloon papillary dilation or sphincteroplasty as an alternative. Methods: We report the outcome in a series of 100 patients in whom balloon sphincteroplasty was attempted for bile duct stones up to 20 mm in diameter, with a median follow-up of 16 months (range 6 to 30). Results: During one ERCP session using sphincteroplasty alone, the bile duct was cleared in 78%, mechanical lithotripsy being required in 10% for stones greater than 12 mm in diameter. Incomplete duct clearance was achieved in a further 4%, all of whom underwent repeat ERCP with successful duct clearance without recourse to sphincterotomy. Failure to clear the bile duct with sphincteroplasty in the remaining 18% was primarily related to large stone size (> 15 mm). Sphincterotomy was required to clear the duct in 7%. Another 6% comprised elderly high-risk patients with multiple large stones greater than 15 mm who were treated by stent insertion plus ursodeoxycholic acid. No papillary hemorrhage was observed; uncomplicated pancreatitis occurred in 5%. During a median follow-up of 16 months, 2% had recurrent symptomatic bile duct stones considered to have been unrecognized following the initial ERCP; these were removed after repeat sphincteroplasty. No clinical evidence of papillary stenosis was observed during follow-up. Conclusions: Endoscopic balloon papillary dilation or sphincteroplasty is a safe and effective alternative to sphincterotomy in the management of bile duct stones less than 12 mm; larger stones may require mechanical lithotripsy to facilitate duct clearance. (Gastrointest Endosc 1995;42:468-74.)

Risk factors for urinary lithotripsy-associated sepsis.

To identify risk factors for sepsis following urinary extracorporeal shock wave lithotripsy (ESWL). Retrospective case-control study with two control groups. A rural, 570-bed, regional referral center. Six cases (four bacteremias and two fungemias) were compared with two sets of 18 controls. Cases had a higher frequency and number of urinary tract infections prior to the procedure and tended to have larger stone size. Patients undergoing ESWL who are at high risk for infectious complications may be identified by preprocedure evaluation. Such patients may require alternative prophylactic regimens and close postprocedure follow-up.

Evolution of the Technique of Combination Therapy for Staghorn Calculi: A Decreasing Role for Extracorporeal Shock Wave Lithotripsy

Percutaneous nephrostolithotomy with or without extracorporeal shock wave lithotripsy (ESWL*) has been extensively used in the management of staghorn calculi, with stone-free rates varying from 23 to 86%. Explanations for the variability of such results include differences in stone burden, differences in percutaneous techniques and an overreliance on ESWL. The results and changing trends in the relative roles of percutaneous nephrostolithotomy and ESWL in the management of staghorn calculi at the Methodist Hospital of Indiana were examined. We reviewed 343 cases of staghorn calculi (partial and complete) with adequate followup data, which were managed with initial percutaneous nephrostolithotomy. Cases were divided into 2 groups: group 1 (252 cases) from 1984 to 1987 when access was performed by a radiologist and group 2 (91 cases) from 1988 to 1990 when access was performed by a urologist.Although stones in group 2 tended to be larger, a decreasing dependence on ESWL was noted (64.7% in group 1 compared to 35.2% in group 2, p <0.001). Despite the larger stone size in group 2, stone-free rates were similar (83.3% in group 1, 86.8% in group 2). In groups 1 and 2 percutaneous nephrostolithotomy alone achieved stone-free rates of 91% and 91.5%, respectively. The stone-free rate with the combination approach was 79.1% and 78.1% in groups 1 and 2, respectively. Technical refinements with percutaneous nephrostolithotomy in group 2 include accurate and carefully selected accesses (superior pole in 36.3%) for best approach to the stone, multiple accesses (13.3%) and improved skills in flexible nephroscopy. Blood transfusion has not been required in group 2 compared with 11.1% in group 1. Mean hospital stay was 12.4 days in group 1 and 10.3 days in group 2 (percutaneous nephrostolithotomy alone, 7.2 days).With careful attention to percutaneous nephrostolithotomy techniques, complex renal stones can be successfully managed endourologically, reducing the need for combination ESWL. Complications previously associated with percutaneous nephrostolithotomy have decreased.