Rapid extracorporeal shock wave lithotripsy for proximal ureteral calculi in colic versus noncolic patients

OBJECTIVES: In delayed extracorporeal shock wave lithotripsy (ESWL) treatment, increasing stone impaction is associated with delayed stone clearance. Whether colic patients treated by rapid ESWL have the same time to stone clearance as noncolic patients, which supports the thesis that stones in both groups are nonimpacted, has not been investigated yet, and was the objective of this study. METHODS: A total of 82 patients were prospectively enrolled and treated with piezoelectric ESWL for a solitary proximal ureteral stone. Of these, 56 patients experienced at least one colic episode compared with 26 noncolic patients. Hydronephrosis has been assessed with the use of ultrasound and intravenous urography (IVU). Time to stone clearance after the first ESWL and stone-free rates after a follow-up period of 3 mo were recorded. RESULTS: In colic and noncolic patients, mean stone size was 7.8mm (p=0.7). Ultrasound-detected hydronephrosis was present in 88% versus 39% (p<0.0001), whereas IVU-detected hydronephrosis was present in 60% versus 7.7% (p=0.0001). Mean number of impulses applied was 8000+/-4000 versus 6700+/-3400 (p=0.1). Mean time to stone clearance was 9.5+/-12.1 d versus 4.6+/-3.8 d (p=0.1). Colic and noncolic patients were considered as treatment success in 83% and 81% after 3 mo of follow-up (p=0.9). CONCLUSIONS: Treatment outcome and time to stone clearance after rapid ESWL in colic patients compared with noncolic patients is comparable and independent of concomitant hydronephrosis. This finding suggests an absence of significant impaction in proximal ureteral stones treated within 24h after a first colic episode, enforcing the concept of performing rapid ESWL in patients harbouring proximal ureteral stones.     

Impact of the degree of hydronephrosis on the efficacy of in situ extracorporeal shock-wave lithotripsy for proximal ureteral calculi

OBJECTIVE: We conducted a prospective randomized study to investigate the relation between the degree of stone-induced hydronephrosis and the outcome of extracorporeal shock-wave lithotripsy (ESWL) in patients with lumbar ureter stones. MATERIAL AND METHODS: A total of 284 patients with solitary lumbar ureter stones with or without hydronephrosis were treated with ESWL. The degree of hydronephrosis was determined by means of renal ultrasound. Patients were divided into four groups according to the degree of stone-induced hydronephrosis. The results were analyzed by comparing stone-free rates, the number of shock waves, the number of sessions, the incidence of complications, secondary interventions and time to stone clearance. RESULTS: The mean stone size was 11.4+/-2.6 mm. In the hydronephrotic group, the stone-free rate was 80.3%, compared to 89.1% in patients without hydronephrosis (p=0.12). The mean time to stone clearance was 13.8+/-9.8 days. Differences among the four groups in terms of stone size and treatment outcome were not significant. However, the presence of hydronephrosis was highly associated with repeat treatment (2.4 vs 1.7 treatments; p<0.001) and prolonged clearance time (16.2 vs 11.6 days; p<0.001). CONCLUSIONS: In cases with solitary lumbar ureter stones, the degree of hydronephrosis caused by the stone does not affect the overall treatment success with ESWL. However, stones in obstructed systems are associated with a tendency for repeat treatment and a prolonged time for stone clearance.     

Extracorporeal Shock Wave Lithotripsy in the Treatment of Proximal Ureteral Stones: Does the Presence and Degree of Hydronephrosis Affect Success?

OBJECTIVES: We investigated the relation between the presence and degree of stone induced hydronephrosis and the outcome of extracorporeal shock wave lithotripsy (SWL) in patients with solitary proximal ureteral stones. METHODS: 130 patients with or without hydronephrosis were treated with SWL. The degree of hydronephrosis was defined by renal ultrasound. Patients were divided into four groups according to the degree of stone induced hydronephrosis. Group 0 (24%) had no urinary system dilatation, group 1 (31.2%) had a mild dilatation of the renal pelvis, group 2 (40%) had a moderate and group 3 (4.8%) a severe dilatation of the renal pelvis and calices. The stone size, number of shock waves applied and number of sessions required to achieve stone clearance were recorded. RESULTS: Mean stone size was 8.2 mm+/-2.5 mm. Mean time to stone clearance was 13.7 days+/-16.3. In 74.4% of patients stone clearance was observed. Additional 4.8% harbored residual fragments < or =3 mm after 3 months. Differences among the four groups in terms of stone size, time to stone clearance and treatment failure were not significant. CONCLUSIONS: The presence or degree of hydronephrosis caused by a proximal ureteral stone does not affect the time to stone clearance or success rate after SWL.     

Significance of age on prognosis in patients treated by extracorporeal shock wave lithotripsy

PURPOSE: To investigate the effect of patient age on the stone-free rate (SFR) in patients with urinary stones treated by extracorporeal shock wave lithotripsy (ESWL). PATIENTS AND METHOD: 138 patients with renal calculi and 463 patients with ureteral calculi were treated using the Siemens Lithostar Multiline. Multiple logistic regression was used to investigate the effect of age and other possible predicting factors, i.e., gender, location, size, side, grade of hydronephrosis, symptom at onset and history of urolithiasis, on the SFR at 3 months after treatment. RESULTS: The overall SFR was 77.2%. The SFRs of aged< = 39, 40-49, 50-59, 60-69 and 70 = < years were 87.4%, 84.4%, 75.0%, 71.1% and 66.3%, respectively. The elder patients complained less frequency of pain at onset and showed more frequency of hydronephrosis. Multiple logistic regression analysis revealed that patient age (younger) as well as stone location (middle and distal ureter), size (small), hydronephrosis (mild or less) and symptom (painful) at onset were a independent (better) prognostic factors determining stone clearance after ESWL of upper urinary tract stones. CONCLUSION: The SFR of elder patients showed lower than that of younger ones, however, the former less needed analgesia for ESWL session than the latter. ESWL is convenient, relatively useful for elder patients.     

Management of painful caliceal stones by extracorporeal shock wave lithotripsy

One hundred and seven patients with caliceal stones causing flank pain were treated by extracorporeal shock wave lithotripsy (ESWL), followed up and reviewed. The total stone-free rate 3 months after ESWL was 38.8%. The total pain-free rate was 50.5%. The pain-free rate was 85% in the stone-free group and 29% in the group with residual stones. No significant differences between the stone-free rate and the duration of pain or age was noted. Patients with abnormal intravenous pyelography (IVP) had a lower stone-free rate than patients with normal IVP (16 vs. 45%, p less than 0.05). The complications included: 6 cases of stone street formation with spontaneous passage; 1 case of stone street formation needing percutaneous nephrolithotomy for drainage; 1 perirenal hematoma; 9 cases of severe colic pain following ESWL; 3 cases of fever following ESWL, and 4 cases of hydronephrosis due to a stone in the ureterovesicle junction. These results show that ESWL is an effective, noninvasive treatment for painful caliceal stones.     

Outcome and safety of extracorporeal shock wave lithotripsy as first-line therapy of lower pole nephrolithiasis

INTRODUCTION: The aim of this study is to assess the efficiency of extracorporeal shock wave lithotripsy (ESWL) as initial therapy for isolated lower pole kidney stones smaller than 20 mm. PATIENTS AND METHODS: During a 24-month period 116 patients with previously untreated single stones under 20 mm in diameter were treated with a Dornier lithotripter S. They were analyzed with regard to stone site and size, number of ESWL sessions, auxiliary measures, retreatment rates, complications and the time taken for stone clearance. RESULTS: 76 patients (65.5%) became stone free, 50 of them (43.1%) within 3 months after ESWL. Depending on stone size the stone-free rates were 67.1% for patients with a stone diameter of <10 mm (59 of 88 patients), and 60.7% for stone diameters between 10 and 20 mm (17 of 28 patients). Complications during and after treatment were rare, i.e. the necessity of ureteral stent insertion due to colic (n = 10), endoscopic stone removal (n = 2), acute pyelonephritis (n = 1), stonestreet (n = 1) and 1 case of hematoma not requiring intervention. The recurrence rate during follow-up (13.2-36.9, mean 25.0 months) was low: 16 patients (13.8%) had recurrent or persistent stones, and 74 patients (63.8%) had no evidence of urolithiasis. CONCLUSIONS: ESWL is a safe and efficient first-line therapy for treatment of isolated small lower pole kidney stones with acceptable stone-free rates, low morbidity, few complications and a low stone recurrence rate.     

Impact of stone size, location, composition, impaction, and hydronephrosis on the efficacy of holmium:YAG-laser ureterolithotripsy

OBJECTIVES: The impact and outcome of holmium:YAG-laser (Ho:YAG) ureterolithotripsy in treating proximal and distal ureteral stones was investigated. METHODS: A total of 543 patients harbouring proximal (n=194) or distal (n=349) ureteral stones underwent semirigid Ho:YAG ureterolithotripsy. The degree of hydronephrosis; stone size, location, impaction, and composition; and complication and stone-free rates were recorded. RESULTS: Mean stone size for proximal and distal stones was 7.1+/-3.6 mm and 6.2+/-2.5 mm, respectively. The stone-free rate on the first postoperative day was 79.4% for proximal and 96.8% for distal stones (p<0.0001). For proximal stones <10mm and > or =10mm, respectively, the stone-free rate was 80.5% and 74.3% (p=0.4) and for distal stones 97.3% and 94.3% (p=0.2). Stone-free rates for radio-opaque versus radiolucent stones in proximal stones were 79.6% versus 77.9% (p=0.8) and 97.6% versus 96.2% in distal stones (p=0.5). Impaction correlated significantly with stone-free rates (p<0.0001). Stone-free rates for nonimpacted versus impacted proximal stones were 85.8% versus 67.2% (p=0.003) and for distal stones 99.2% versus 91.4% (p<0.003), respectively. The presence or degree of hydronephrosis did not correlate with treatment success (p=0.4, p=0.8). The presence of intraoperative complications correlated significantly with proximal compared to distal ureteral stone location (p=0.004). Auxiliary measures in proximal versus distal stones were performed in 20.6% versus 2.9% (p<0.0001). CONCLUSIONS: In this series, stone-free rates in Ho:YAG ureterolithotripsy were significantly higher in distal and nonimpacted stones but were independent of stone size and composition and the degree of hydronephrosis. Ureterolithotripsy in proximal stones was associated with higher intraoperative complication and retreatment rates compared to distal stones.     

Piezoelectric lithotripsy of radiopaque gallstones: results and six-month follow-up

Sixty-eight patients with radiopaque gallbladder stones (38 with a single stone, 30 with multiple stones) were treated with piezoelectric extracorporeal shock wave lithotripsy (ESWL) and results were compared with those of 69 patients with radiolucent stones (28 with a single stone, 41 with multiple stones). Stones were fragmented to 4 mm or less in 76.8% after 41,466 +/- 36,504 shock waves in the radiolucent stone group and 77.9% after 54,686 +/- 51,024 shock waves in the radiopaque stone group (p = 0.876 and 0.130, respectively). In 137 patients, ten patients were lost to follow-up. Average period of follow-up was 220 +/- 198 days. Six-month clearance rate of the radiolucent stone group was 43.5% and that of the radiopaque stone group was 16.4% (p less than 0.05) Figure 1. Six-month clearance rate of patients with single stones smaller than 2 cm was also significantly higher in the radiolucent stone group than in the radiopaque stone group (69.5% vs 18.6%; p less than 0.01). However, in patients with multiple stones, the presence of calcification did not affect rates of successful fragmentation or 6-month clearance. There was no statistically significant difference in incidence of complications between the radiolucent and radiopaque stone groups. Although the number of cases are small and the follow-up period is short, our results of ESWL on radiopaque gallstones are so far not satisfactory in terms of stone clearance. Strict patient selection is needed unless there is an improvement in the lithotripsy procedure or post-lithotripsy management.     

Emergency extracorporeal shock wave lithotripsy (ESWL) for obstructing ureteral stones

OBJECTIVE: To evaluate emergency treatment of obstructing ureteral stones by in situ extracorporeal shock wave lithotripsy (ESWL) during acute renal colic. PATIENTS AND METHODS: From January 1994 to February 2000, 200 patients (mean age: 42 years) were treated by ESWL (EDAP LT-02) for obstructing ureteral stones causing acute renal colic refractory to medical treatment or recurring within 24hours of such treatment. Stones were visualised by fluoroscopic imaging and/or ultrasound. Follow-up included radiological and/or ultrasound examinations and lasted three months. RESULTS: Mean stone size was 7mm (3-20mm). At three months, 164/200 (82%) patients were stone-free. This rate ranged from 79% to 83% according to the location of the stone, and from 75% to 86% according to the size of the stone. These differences in rate were not significant. Two or three ESWL sessions were required in 79 patients. ESWL was well tolerated in 90% of patients. The only complication was a case of pyelonephritis requiring the placement of a JJ stent, administration of antibiotics, and distant ureteroscopy. The 36 patients, in whom ESWL failed, underwent ureteroscopy (n=23) or lithotripsy with a Dornier machine (n=13). CONCLUSION: Non-deferred ESWL for acute renal colic secondary to obstructing ureteral stones has a satisfactory success rate and very low morbidity.     

Prospective randomized evaluation of emergency extracorporeal shock wave lithotripsy (ESWL) on the short-time outcome of symptomatic ureteral stones

OBJECTIVE: Here, we report the results of a randomized controlled trial (RCT) assessing the efficacy of emergency ESWL (eESWL) on the short-term outcome of symptomatic ureteral stones. MATERIAL: The trial enrolled 100 patients admitted in emergency room for renal colic caused by a ureteral radioopaque [corrected] stone. Patients were randomized to medical therapy alone or combined with eESWL. eESWL was performed within 6 hours of the onset of renal colic without specific analgesia on a Lithostar lithotripter (Siemens Medical, Munich, Germany). The primary endpoints were the proportion of patients stone free rate after 48 hours (SF-48) and the cumulative proportion of patients discharged from the hospital after 48 and 72 hours. RESULTS: Ureteral stone's location was proximal and distal in respectively 46% and 54% of the patients; stone's mean size was 5.5 mm (range 2-10 mm). Median hospital stay was 3 days, ranging from 1 to 14 days. SF-48 in the control group varied from 76% for distal stones <5 mm to 28.6% for proximal stones >5 mm, averaging at 61%. On average, eESWL increased SF-48 by 13% (p: 0.126), the gain strictly depending on stone size and location. SF-48 increase ranged from 40% for proximal stones >5 mm to 1.8% for distal stone <5 mm. On average, eESWL increased the median duration of hospital stay by one day. This mean negative impact results from ESWL increasing significantly the duration of hospital stay in case of distal stone, while slightly shortened it for stones located proximally. CONCLUSION: This study demonstrated for the first time that rapidly performed ESWL is a valuable therapeutic option to improve elimination of ureteral stones and shorten duration of hospital stay, proven that the stone is located proximally to the iliac vessels.     

输尿管结石行体外冲击波碎石治疗后发生输尿管狭窄的危险因素分析

目的探讨输尿管结石经体外冲击波碎石治疗后发生狭窄的危险因素。方法收集2006年7月至2011年7月就诊于我院首次行体外冲击波碎石治疗的输尿管结石患者的临床资料,先对所取临床指标进行单因素分析,然后进行Logistic多因素回归分析。结果共收集行体外冲击波碎石的输尿管结石患者174例,其中发生术后输尿管狭窄的患者15例,狭窄发生率为8.62%,单因素分析显示:结石长径、肾积水程度、结石嵌顿时间以及碎石次数与术后输尿管狭窄发生相关,多因素Logistic回归分析结果显示:结石长径、肾积水程度以及碎石次数是患者发生输尿管狭窄的独立危险因素。结论对于肾积水程度较重、结石长径较大、预期碎石次数较多的输尿管结石患者,行体外冲击波碎石后发生狭窄的可能性相对较高,在治疗选择上应更加慎重,提倡选择体外冲击波碎石之外更加安全有效的治疗方式。     

Treatment of painful caliceal stones

Nonmobile caliceal stones cause pain more often than previously appreciated. The character and intensity of the pain differs from typical renal colic. Twenty-six patients with caliceal stones and pain underwent attempted treatment for pain control via stone removal or disintegration: 15 were treated with percutaneous stone extraction (PSE), 10 with extracorporeal shock-wave lithotripsy (ESWL), and 1 required open surgery after failing PSE. One patient had persistent pain after ESWL and subsequently underwent PSE; 25 of 26 patients had complete relief of pain. Morbidity was minimal. Patients with painful caliceal stones should be offered ESWL, followed by PSE if pain persists.     

影响第二次冲击波碎石术治疗上尿路结石患者成功的因素分析

目的 探讨影响第二次冲击波碎石术（extracorporeal shock wave lithotripsy, ESWL）治疗上尿路结石患者成功的因素。方法 回顾性分析2008年1月至2012年12月来本院接受第二次ESWL治疗的上尿路结石患者120例。根据患者上尿路结石有无完全排出分为成功组（n=80）和失败组（n=40）。回顾性分析所有患者的病历资料,相关因素分析包括性别、年龄、病程、BMI、结石侧别、结石位置、结石长度、结石宽度、结石数目、肾绞痛、血尿、肾积水程度、非增强螺旋CT值、冲击次数、冲击能量等指标。应用单因素、多因素非条件Logistic回归分析上尿路结石患者第二次ESWL治疗成功与否的危险因素分析。结果 120例上尿路结石患者临床特征显示,两组在病程、BMI、结石长度、结石宽度、结石数量、肾绞痛、肾积水程度、CT值、冲击次数方面差异有统计学意义（P＜0.05）,在性别、年龄、结石侧别、结石位置、血尿、冲击能量方面差异无统计学意义（P＞0.05）。经单因素、多因素 Logistic 回归分析结果显示,BMI偏高、结石长度＞2 cm、存在肾绞痛、肾积水程度严重、CT值＞750 HU会增加上尿路结石患者第二次ESWL治疗失败的风险（P＜0.05）。结论 临床医师利用ESWL第二次治疗上尿路结石患者过程中,应格外注意患者BMI、结石长度、肾绞痛、肾积水程度、CT值等关键指标。     

Pelvi-calyceal height, a predictor of success when treating lower pole stones with extracorporeal shockwave lithotripsy

Extra corporeal shockwave lithotripsy (ESWL) is the treatment of choice for the majority of renal stones, however, it has the lowest success rate in complete clearance of stones located in the lower pole. We assess whether pelvi-calyceal height is a useful measurement in predicting successful stone clearance from the lower pole. A total of 105 patients with a solitary lower pole calculus of less than 20 mm treated with ESWL were reviewed. Stone size, location and pelvi-calyceal height were measured by intravenous urogram. Success was defined as complete stone clearance. Fifty-four patients (51.4%) had successful treatments, with the remaining 51 (48.6%) having incomplete stone clearance (including two patients in whom treatment had no effect). There was a statistically significant difference (P<0.0001) in pelvi-calyceal height between the two groups. Mean pelvi-calyceal height in patients with complete stone clearance was 15.1 mm (SD=3.9) compared with 22.9 mm (SD=5.2) for those with incomplete clearance. Pelvi-calyceal height is a useful predictor of success when treating lower pole renal stones with ESWL.     

急诊输尿管镜治疗输尿管结石并首次肾绞痛的疗效观察

目的 评价急诊输尿管镜治疗输尿管结石并首次肾绞痛的疗效.方法 本院2010年7月至2011年7月期间收治的140例输尿管结石患者纳入本研究范畴,其中60例输尿管结石患者首次肾绞痛时就诊,急诊行输尿管镜钬激光碎石,纳入第一组；80例患者对症处理后立即入院或肾绞痛再次发作入院并常规检查后再行输尿管镜钬激光碎石,纳入第2组.对两组患者的碎石效果、辅助治疗及相关并发症等指标进行比较,行统计学分析,得出结论.结果 140例患者均经输尿管镜检查,第1组结石大小0.80±0.31 cm,结石一次性清除率96.67％,无患者因结石疼痛再次就诊；第2组结石大小0.75±0.35 cm,结石一次性清除率95.00％,因结石疼痛再次就诊次数2.03±1.85,两组患者无严重并发症发生.结论 急诊输尿管镜治疗输尿管结石并首次肾绞痛安全可行,能及时解除疼痛.     

Cost effectiveness of extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy for medium-sized kidney stones. A randomised clinical trial.

To evaluate percutaneous nephrolithotomy (PNL) and extracorporeal shock wave lithotripsy (ESWL) for their clinical effects, their cost effectiveness, their complication rates, and the patients' experiences, 55 consecutive patients were randomised to have one or other operation between October 1986 and October 1988. Six patients were excluded, 21 were treated with PNL and 28 with ESWL as primary treatment. Mean hospital stay and length of treatment were longer for PNL than for ESWL. Since 1 July 1987 all patients having ESWL have been treated without anaesthesia (n = 15), whereas epidural anaesthesia was used for all PNL. Slightly more of the ESWL patients experienced some pain during treatment. Minor complications or pain were more common after ESWL during the first 10 days after discharge from hospital. If patients with stone fragments of 4 mm or less were regarded as having a successful outcome, the success rates after one year were 94% for PNL and 77% for ESWL. The overall total cost was lower for ESWL than for PNL, the cost per successfully treated patient being 2172 pounds for PNL and 1810 pounds for ESWL. Medium sized kidney stones (6-30 mm, or 2-3 stones of 20 mm or less) can be efficiently and cheaply treated by both PNL and ESWL, though the cost of ESWL is lower. Even if effects other than cost (such as complications and patients' experience) are borne in mind, ESWL was superior to PNL for this group of patients.     

Is ureteral stenting necessary after uncomplicated ureteroscopic lithotripsy? A prospective, randomized controlled trial

PURPOSE: We conducted a prospective, randomized controlled study to investigate the advantages and disadvantages of ureteral stenting after ureteroscopic lithotripsy. MATERIALS AND METHODS: A total of 60 patients who underwent ureteroscopic lithotripsy were equally randomized into a stented or a nonstented group. The inclusion criteria were stone 6 to 10 mm., absence of polyp or stricture in the ureter and no mucosal injury during ureteroscopy. The operation was performed with a 6Fr rigid ureteroscope without ureteral dilation and stones were fragmented with a 1.9Fr electrohydraulic lithotriptor without extraction. A 7Fr double pigtail stent was placed in the stented group for 3 days after ureteroscopy. Urinalysis, plain x-ray and renosonography were performed before and after lithotripsy in each patient. Subjective symptoms and pain score were recorded on admission to the hospital and 3 days postoperatively. RESULTS: The stone-free rate was 100% in each group and preoperative hydronephrosis equally resolved in both groups. Mean pain score plus or minus standard deviation improved significantly in the nonstented (6.33 +/- 1.81 preoperatively to 2.30 +/- 1.93 postoperatively, paired Student's t test p <0.0001) and stented (7.10 +/- 1.03 to 2.30 +/- 2.22, p < 0.0001) group. There was no statistical difference in pain reduction between the 2 groups (p = 0.18). The amount of extra parenteral analgesic used was similar in both groups. One patient in the nonstented group visited the emergency room for postoperative renal colic, 25 (83.3%) patients in the stented group complained of at least 1 irritative bladder symptom and only 4 (13.3%) in the nonstented group experienced bladder discomfort. CONCLUSIONS: After uncomplicated ureteroscopic electrohydraulic lithotripsy patients without ureteral stenting tend to have similar renal function recovery and satisfactory pain reduction with less irritative symptoms compared to those treated with a ureteral stent. We suggest that it is not necessary to place a ureteral stent routinely after uncomplicated ureteroscopic electrohydraulic lithotripsy for stones smaller than 1 cm.     

Noninvasive anesthesia,analgesia and radiation-free extracorporeal shock wave lithotripsy for stones in the most distal ureter: experience with 165 patients

PURPOSE: Spontaneous ureteral stone passage often causes severe renal colic, especially when the stone passes through the narrow ureteral orifice. In these situations noninvasive anesthesia-free, analgesia-free and radiation-free extracorporeal shock wave lithotripsy (ESWL) (Dornier Medical Systems, Marietta, Georgia) is a valuable tool. It can be performed at any time without needing any further patient preparation. MATERIALS AND METHODS: A total of 165 patients underwent ESWL using the Lithostar Ultra device (Siemens, Erlangen, Germany). Only ureteral calculi within 5 cm. of the ureterovesical junction were included in this study. Patients were treated while supine and stones were localized by ultrasound through the filled bladder without x-ray exposure. Treatment was started without anesthesia or analgesia and analgesics were administered only at patient request during treatment. RESULTS: Of the patients 93% were treated without anesthesia or analgesia and 7% required a single intravenous dose of 25 mg. pethidine. Postoperatively renal colic developed in 40 patients (24%). In 4 cases (2.4%) renal drainage was required for analgesia resistant pain or obstructive pyelonephritis. On day 1 after ESWL 90% of the patients were stone-free or had fragments 2 mm. or less, while 10% had residual fragments 3 mm. or greater. Of all patients 7% were re-treated once. At 3 months postoperatively 129 of the 130 evaluable patients (99%) were stone-free. CONCLUSIONS: ESWL of stones located in the most distal ureter using the Lithostar Ultra device is effective, safe and radiation-free. It is done without anesthesia and in most cases without analgesics. This simple and noninvasive procedure is an excellent first line treatment modality for prevesical stones and it represents a valid alternative to conservative management or invasive endoscopy.     

In situ extracorporeal shock wave lithotripsy for obstructing ureteral stones with acute renal colic.

In situ (no instrumentation) extracorporeal shock wave lithotripsy (ESWL*) was used to treat 49 patients with obstructing ureteral stones causing acute renal colic. Ureteral obstruction was diagnosed on the delayed films of an excretory urogram and was classified as severe (dilatation above and no contrast medium seen below the stone) in 17 patients and partial (dilatation above and contrast medium seen below the stone) in 32. Upper third ureteral stones were present in 41 patients (obstruction severe in 15 and partial in 26) and lower third ureteral stones were present in 8 (obstruction severe in 2 and partial in 6). ESWL was performed within 14 days of the onset of the acute renal colic because of persistent pain with an unmodified Dornier HM3 lithotriptor in 17 patients and a Medstone STS device in 32. With single stones the stone-free rate at 3 months, the repeat ESWL rate and the secondary procedure (stone basketing) rate were 92%, 6% and 8%, respectively, with severe obstruction, and 78%, 6% and 6%, respectively, with partial obstruction. No urinary drainage procedures for sepsis were required after ESWL. Obstructing ureteral stones, which presented mainly in the upper third of the ureter, were successfully treated with in situ ESWL without the need for either bypassing the stone with a ureteral stent or for pushing the stone back into the kidney before treatment with ESWL.     

The impact of radiological anatomy in clearance of lower calyceal stones after shock wave lithotripsy in paediatric patients

OBJECTIVE: To determine the factors affecting stone clearance after extracorporeal shock wave lithotripsy (ESWL) in children with lower calyceal stones. MATERIALS AND METHODS: Lower pole stone clearance was reviewed in 34 patients aged between 2 and 16 years (23 boys and 11 girls) treated with ESWL between 1989 and 2001 in our clinic. Renal anatomy was determined on standard intravenous urograms. The lower infundibulopelvic angle (IPA) was measured by two different methods based either on measuring the angle between vertical pelvis axis and vertical axis of lower infundibulum or finding the angle between the ureteropelvic axis and vertical axis of lower infundibulum. RESULTS: The mean age of the patients was 12.1+/-4.16 (2-16) years. The mean stone burden was found as 96.93+/-87.13 mm(2) and the mean shock wave number per session and power as 2631.4+/-593.1 and 17.57+/-1.1 kV, respectively. The stone-free rate was 55.9%. Fifteen (44.1%) cases had residual fragments retained in lower calices after lithotripsy and are still followed. The stone clearance was found to be unrelated to stone burden and infundibulum width (p=0.44 and p=0.34, respectively). However, a significant difference was present between mean lower pole infundibular length (p=0.0032) and lower IPA measurements according to both methods between stone-free cases and others. The most remarkable factor that had a significant influence on stone clearance was an acutely oriented infundibulum defined according to IPA-ureteropelvic axis angle determination method (p=0.00001) followed by Sampaio's pelvic axis method (p=0.0001). Only 1 (5%) patient was stone-free under 40 degrees and 1 (6%) case with an angle of 45 degrees had residual fragments in the former method. Similarly none of the cases had residual fragments over 90 degrees for Sampaio's method and 90% of the stone-free cases had a more obtuse angle. Thus, we determined that a cut-off point of 40 degrees for the IPA-ureteropelvic axis method and 90 degrees for Sampaio's method was most useful to determine the clearance of lower pole fragments. CONCLUSION: The factors affecting stone clearance in paediatric patients are similar to adults.