Extracorporeal shock wave lithotripsy of calcified gallstones. Work in progress

Thirty-eight patients with calcific cholecystolithiasis underwent extracorporeal shock wave lithotripsy (ESWL) of the gallbladder on an outpatient basis. Twenty-two (60%) patients had fragments smaller than 3 mm on follow-up ultrasound (US) studies after an average of 13,450 shock waves and four lithotripsy sessions. Nineteen of these 22 patients were followed up for an average of 18 weeks, and only three were found to be free of residual fragments at US. The other three patients were lost to follow-up. Sixteen patients are still undergoing biliary ESWL. Comparison of calcified and noncalcified gallbladder calculi revealed that calcified stones required 50% more shock waves for successful fragmentation, fragments cleared considerably more slowly from the gallbladder, and patients had a higher frequency of acute pancreatitis (5% vs 2%) and transient hematuria (8% vs 3%). Stones with dense homogeneous calcification required significantly fewer shock waves for successful fragmentation than stones with calcific lamination. ESWL can be applied occasionally in patients with calcific cholecystolithiasis if an alternative to surgery is required, but success has been limited.     

Comparison of ultrasonography and oral cholecystography in lithotripsy. II. Determining retreatment

Both ultrasonography (US) and oral cholecystography (OCG) are being used to evaluate patients after extracorporeal shock wave lithotripsy (ESWL) for gallstones. Criteria for retreatment after the initial ESWL are usually related to the size of the residual fragments. This study examines the efficacy of ultrasound and OCG for determining both the size and number of stone fragments in the gallbladder in an in vitro model and in patients. Ultrasonography and OCG examinations using an in vitro ESWL phantom with ten groups of stones, and on 39 patients, were reviewed independently by three radiologists to determine both the size and number of stone fragments. For the in vitro study, the three readers estimated the correct number of fragments, or the next closest range, in 87% of observations by OCG and in 43% by US. The size of the largest fragment was measured within 1 mm of its actual size in 87% of observations by OCG and 20% by US. Correlation coefficients for the mean measurements of the three readers versus the actual fragment size and number were greater for OCG than for US. For the in vivo study, the three readers agreed in 47% of the OCG versus 32% of US examinations with respect to the number of fragments, and in 65% of OCG compared to 40% of US studies with respect to size of the largest fragment. Multiple statistical analyses demonstrate that these differences are statistically significant. A discrepancy among the readers concerning whether a patient was eligible for retreatment occurred in 15% of OCG as compared to 45% of US studies. Both the in vivo and in vitro studies indicate that there is more interobserver reproducibility for OCG than for US, and that OCG is more reliable in making the decision concerning patient eligibility for retreatment following lithotripsy.     

Renal stone disease treated with extracorporeal shock wave lithotripsy: short-term observations in 100 patients

The immediate posttreatment findings are described for 100 patients who underwent extracorporeal shock wave lithotripsy (ESWL) for renal stone disease. Excretory urography was performed both before and 24-72 hours after ESWL. In 21 patients, stones were completely disintegrated, and stone fragments were passed rapidly. Stones were fragmented but not passed entirely within 24-72 hours in 76 patients. There was no appreciable effect on stones in three patients. In nine of 27 patients who had mild to severe ureteral obstruction caused by stone fragments, relief procedures (retrograde ureteral manipulation or percutaneous stone extraction) were necessary. Overall, 70 patients experienced successful stone disintegration without complications. Continued investigation is needed to determine prevalence of residual calculi, reversibility of acute effects of ESWL on the kidney, and possible development of late hypertension.     

Complications of the treatment of renal calculi by extracorporeal lithotripsy. Prospective evaluation of 80 treated kidneys

The acute effects of extracorporeal shock wave lithotripsy (ESWL) on morphology and function of the kidney were prospectively evaluated by abdominal radiography, ultrasonography and contrast-enhanced computed tomography, in 80 treated kidneys. Two types of complications were demonstrated: 1. Obstruction of the ureter by stone fragments in 25% of cases. Relief procedures became necessary in 5 patients (6% of the 80 cases). 2. Limited injuries of the kidney and perirenal spaces in 44% of cases: parenchymatous abnormalities 17.5%; subcapsular hematoma 12.5%; perirenal fluid collection 24%. No treatment was necessary and morphologic abnormalities disappeared in one or two months post-ESWL. Severe ureteral obstruction after ESWL seems to be related to stone size. No definitive evidence that kidney's injury was related to the number of shock waves applied to the kidney was found.     

The value of extracorporeal shock-wave lithotripsy in the management of bile duct stones

We evaluated the role of biliary extracorporeal shock-wave lithotripsy in treating 70 symptomatic patients with bile duct stones in whom endoscopic or percutaneous radiologic attempts at basket extraction had failed. Forty-four patients had common bile and/or common hepatic duct stones, 21 patients had cystic duct stones, and five patients had intrahepatic duct stones. A total of 43 patients (61%) had complete elimination of stone fragments during the initial treatment period. If patients in whom stones were successfully fragmented yet not totally eliminated on initial hospital treatment but who were asymptomatic at follow-up times of 8-22 months are included, the overall successful treatment rate was 83%. Stones were cleared in 26 of 44 common bile/hepatic duct stone patients, spontaneously in seven patients and after endoscopic or percutaneous radiologic intervention in 19 patients. Fifteen (71%) of 21 patients had cystic duct stones successfully cleared. The fragments in two of five patients with intrahepatic duct stones also were cleared. Five patients (7%) had minor side effects. Seven (10%) of 70 patients went on to have surgery. Complications after 30 days occurred in five patients (7%); two required repeated endoscopy with fragment extraction, two required placement of an endoprosthesis, and one died. We conclude that biliary extracorporeal shock-wave lithotripsy is valuable as an adjuvant to standard interventional techniques for removing bile duct stones.     

Common bile duct and intrahepatic stones: results of transhepatic electrohydraulic lithotripsy in 50 patients

Percutaneous, transhepatic, intracorporeal, electrohydraulic shock wave lithotripsy was performed in 50 patients after failure of endoscopic treatment (n = 43) or directly in patients with a strictured hepaticojejunostomy (n = 7). Twenty-seven patients had common bile duct stones; 23, intrahepatic stones. Three steps were used: A transhepatic bilicutaneous fistula was created, a wide communication between the bile duct and the gut was established, and contact shock wave lithotripsy was performed under endoscopic guidance. Afterward, 46 patients were free of stones. In four patients with diffuse intrahepatic lithiasis, only 75% of stones could be cleared. Severe complications, seen in 11 patients (hemobilia necessitating transfusion [n = 6], bile duct perforation resulting in cholangitis [n = 3], acute pulmonary edema [n = 1], and hemothorax [n = 1]), were fatal in four patients; all occurred early in the study. The authors modified their technique by dilating the biliary tract in two sessions 3 days apart, waiting 6 days for the tract to mature, and then introducing the cholangioscope directly through the skin, significantly reducing complications and mortality (P less than .005).     

Biliary complications of gallstone lithotripsy detected by Tc-99m DISIDA scintigraphy

Extracorporeal shock wave lithotripsy (ESWL) has been reported to be a safe and relatively effective non-invasive treatment for radiolucent gallbladder calculi in selected patients. Ideally, the goal of successful treatment is the passage of all fragments from the gallbladder into the intestinal tract. Biliary colic has been reported in up to 35% of treated patients, although complications such as cholecystitis, cholangitis, common bile duct obstruction, and pancreatitis are surprisingly infrequent. Cholescintigraphy is the procedure of choice in patients with biliary colic and suspected acute cholecystitis. It has proven to be more sensitive than ultrasound in detecting acute common bile duct (CBD) obstruction, since functional obstruction precedes morphologic dilatation of the CBD. This report reviews two cases of post-lithotripsy cystic and common duct obstruction and discusses the role of Tc-DISIDA scintigraphy following gallstone ESWL.     

Cholecystolithiasis: Three years experience with ultrasound-guided electromagnetic shock-wave lithotripsy

In a three-year period, 207 patients with cholecystolithiasis were referred to an interdisciplinary team at our hospital to evaluate the possibility of non-surgical treatment. Fifty-eight patients were found eligible for extracorporeal shock-wave lithotripsy (ESWL); 50 of them underwent ESWL on an outpatient basis with adjuvant bile acid therapy. Thirty patients (60%) had single stones, 14 (28%) had two or three stones, and 6 (12%) had five-ten stones. The mean total stone volume of all patients was 2,5 cm³, equivalent to a single stone of 1.7 cm diameter; 6 patients (12%) had slightly calcified stones. Successful stone fragmentation (fragments <- 4 mm) was achieved in 45 patients (90%). In the remaining 5 patients (10%) with residual fragments > 4 mm, ESWL was considered a failure and elective cholecystectomy was eventually performed or recommended. All patients received adjuvant oral bile acid therapy. The stone clearance rates after 3, 6, 12 and 18 months were 29%, 50%, 83% and 95% in patients with single stones and 22%, 40%, 64% and 88%, respectively, in all patients. The duration of treatment in 32 patients who have cleared all their gallstone fragments to date, was 8.5 months (range: 0.4–20.4 months); all of these patients are also free of their initial symptoms. Sideeffects and complications of ESWL included biliary colic in 17 patients (34%), mild acute pancreatitis in 1 patient (2%) and acute cholecystitis requiring emergency cholecystectomy in another patient (2%). The electromagnetic device and the protocol we used is well suited for ambulatory treatment of patients with a limited stone volume. A fragment size <- 4 mm was usually achieved with 2 treatment sessions and appears to be a reasonable endpoint of ESWL. Although laparoscopic cholecystectomy is now a routine procedure in our hospital, we believe that ESWL remains a valid treatment option in selected patients.Presented at the ECR '91 Scientific Assembly, Vienna, Austria, 19 September 1991 Correspondence to: C. D. Becker     

Computed tomography density of gallbladder stones may aid in predicting the rate of stone fragmentation with extracorporeal lithotripsy

Thirty-six patients with gallbladder stone(s), 21 with solitary stone and 15 with multiple stones up to five in number, were treated by a single session of extracorporeal shock wave lithotripsy. In eight patients (group A), stones were gradually fragmented from the surface, producing fine powderlike fragments which made residual stones invisible, leading to reduced therapeutic efficacy. In 13 patients (group B), residual stones remained visible up to 2,400 shocks, though they showed similar fragments. Such fragments did not appear throughout treatment in 14 patients (group C). Computed tomography (CT) attenuation number, when the region of interest was settled on the whole stone, increased in the order of group A, B, and C. When the distribution of CT density on stones was analyzed, the density was diffusely lower than 50 HU in all patients in group A, higher than 50 HU only on the surface in all patients except for two in group B, and diffusely higher than 50 HU in all patients except for one in group C. CT findings may be useful for predicting the fragmentation mode of gallbladder stones by extracorporeal shock wave lithotripsy.     

Intact stones or fragments? Potential pitfalls in the imaging of patients after biliary extracorporeal shock wave lithotripsy

Ultrasound is used after extracorporeal shock wave lithotripsy of gallbladder stones to assess fragmentation. In many patients with apparently successful fragmentation, the posttreatment studies show an intraluminal, echogenic focus within the gallbladder, with posterior acoustic shadowing characteristic of an intact stone. Cholesterol gallstones were fragmented in vitro by means of lithotripsy, and the sonographic appearance of the fragmented stones was followed up over time to study factors that might affect the process. After lithotripsy, fragments settled and produced an echogenic focus with posterior shadowing indistinguishable from the appearance of an intact stone. These experimental observations led to the development of a clinical maneuver to overcome the diagnostic pitfalls posed by the reaggregation of stone fragments in situ. This rollover maneuver helps distinguish between intact stones and fragments, and prevents both diagnostic errors in follow-up and unnecessary retreatment.     

Treatment of bile duct stones by laser lithotripsy: results in 12 patients.

We used a pulsed tunable dye laser (operating at 60 mJ per pulse, 504-nm wavelength) to fragment large (0.8-4.5 cm) stones retained in the hepatic ducts or common bile duct in 12 patients after cholecystectomy. Attempts to extract stones via a T-tube or endoscope had been unsuccessful in all patients. In nine of 12 patients, all stone fragments were successfully eliminated during the initial treatment. In one patient, fragmentation occurred but debris remained, requiring endoscopic stenting. Pseudomonas sepsis developed in this patient 30 days after the procedure and was treated by extraction of the stone fragments. Fragments remaining after lithotripsy were cleared at the same sitting by using saline flushing or endoscopic or percutaneous basket extraction. In two of 12 patients, the treatment was unsuccessful because of laser malfunction. The treatment was performed without complications, except for clinically insignificant hyperamylasemia, which occurred in two patients. Our experience suggests that laser lithotripsy offers a safe alternative for nonsurgical treatment of large retained biliary stones for patients in whom traditional treatments have failed.     

Biliary lithotripsy: in vitro analysis of gallstone fragmentation for equivalent stone volumes

The relationship between gallstone fragmentation during extracorporeal shock wave lithotripsy (ESWL) and gallstone volume is poorly understood. Clinical results of ESWL show that the highest stone-free rate at 6 months occurs with radiolucent single gallstones 20 mm or less in diameter. In an in vitro study, individual gallstones from cholecystectomy specimens were divided by size and composition into nine single- and nine multiple-stone groups; the stones were then paired on the basis of similar volume. ESWL was performed in a phantom and the size of the largest fragment was measured at 500, 1,000, and 1,500 shock waves. At 1,500 shock waves, sandlike particles were present in six of nine single stones versus two of nine multiple stone groups; the mean size of the largest fragment at 1,500 shock waves was 2.1 mm (single) and 4.4 mm (multiple) in diameter. When corrected for volume, the authors' data suggest that single stones are more easily broken into fragments smaller than 5 mm in diameter than multiple gallstones. The implication, especially when spark-gap technology is used, is that more shock wave energy (ie, an increased number of shock waves at a higher kilovoltage) will be necessary to achieve the same results when treating patients with multiple stones versus a single gallstone with a similar stone volume.     

Extracorporeal cholecystolithotripsy without oral chemolitholysis

One hundred thirty-six patients completed extracorporeal biliary lithotripsy (EBL) for symptomatic cholecystolithiasis. Sonographic evidence of complete clearance of all stone fragments was the only criterion for treatment success, which occurred in 32 of the 71 patients (45%) followed up for 24 weeks and in 36 of the 59 patients (61%) followed up for 52 weeks. The authors' protocol varied from protocols of other researchers primarily in that no adjuvant chemolitholysis was used. However, the number of treatment sessions and total number of shock waves (a maximum of 4,000 shock waves per treatment session, 12,000 shock waves in a patient demonstrating no significant fragmentation, and 20,000 shock waves in a patient whose stones responded well to fragmentation) was higher than those in other reports. The results of treatment and complication rates in this study are comparable with those at centers using both shock-wave lithotripsy and chemotherapy. The authors conclude that EBL is developing into an important alternative to surgery, which was obviated in all patients with complete clearance of fragments from the gallbladder.     

Renal calculi: sensitivity for detection with US

The sensitivity of sonography in the detection of renal calculi was tested in a three-phase study in 100 patients. In phase 1, ultrasonographic (US) scanning was performed after review of abdominal radiographs and renal tomograms in 30 patients who had undergone extracorporeal shock wave lithotripsy (ESWL). In this group the sensitivity of US for detecting stones was 98%. In phase 2, scanning was performed in 30 post-ESWL patients without prior review of radiographs or tomograms. The sensitivity of US for stone detection in this group was 95%. In phase 3, sonography was performed in a blinded fashion on a random mix of post-ESWL patients and patients who had undergone urography for reasons unrelated to nephrolithiasis. The sensitivity of US for stone detection in this group of 40 patients was 91%. The overall sensitivity in all three groups was 96%, which was superior to the performance of abdominal radiography and slightly inferior to the combination of abdominal radiography and renal tomography. The ability to detect kidney stones with US depended on stone size but was independent of stone location or patient size. The study findings suggest that US is an effective means for detecting kidney stones in patients with suspected nephrolithiasis.     

Use of an electrohydraulic lithotripter in the percutaneous treatment of biliary tract calculi. The preliminary clinical experience in 4 cases

The results are reported of percutaneous transhepatic treatment with an electrohydraulic lithotripter in 4 cases of bile duct lithiasis. An electric discharge, generated by a bipolar electrode, gives origin to high-amplitude and low-frequency shock waves in the fluid medium which cause the stone to fragment. Complete resolution of lithiasis was obtained in 2 patients with intrahepatic calculosis. In the other 2 cases of massive lithiasis of intra and extrahepatic bile ducts the treatment, however incomplete, proved to be useful, as the biliary flux was rehabilitated and clinical symptoms disappeared. No relevant immediate side-effects were observed, except for well-tolerated pain during the discharges, and transitory hemobilia which solved spontaneously. No complications were observed in this series of patients. Electrohydraulic lithotripsy proves thus to be useful for supporting standard interventional radiology techniques in very complex cases of intra- and extrahepatic bile duct stones.     

Gallstone extracorporeal shock-wave lithotripsy: time and treatment considerations

We evaluated 30 gallstone lithotripsy procedures performed on 27 patients with the Dornier MPL-9000 Lithotripter to determine how time was spent in the lithotripsy suite and to evaluate the various technical reasons for interrupting the administration of shock waves during the treatment. The procedure averaged 98 +/- 32 min total time in the lithotripsy suite. This included an average of 22 +/- 6 min before the treatment, 70 +/- 28 min for administration of shock waves, and 6 +/- 2 min after the treatment. The time required to deliver the shock waves did not correlate with patient age, sex, or weight; the number of gallstones; or the number or date of the treatment. However, a trend was seen toward an association between shorter treatment times and larger stone volumes. On the average, the administration of shock waves was interrupted every 48 shock waves for various reasons. Electronically changing the imaging plane of the in-line sonographic transducer to retarget the stone in the focal zone was by far the most frequent reason for interrupting shock-wave delivery, averaging 56 shock waves between changes. We conclude that extracorporeal shock-wave lithotripsy of gallstones is a time consuming and technically demanding procedure that requires continuous monitoring and frequent interruption in order to optimize targeting and fragmentation of the stone(s) while maintaining the patient's comfort.     

Extracorporeal shock wave lithotripsy: interventional radiologic solutions to associated problems

Among 1,500 patients treated with extracorporeal shock wave lithotripsy, 1,300 had calculi less than 2.5 cm in diameter and 200 had calculi of 2.5 cm or larger. Although most patients did well and required no further radiologic intervention, 178 interventional radiologic procedures were performed. Urinary tract obstruction often developed in patients with large stones when the collecting system filled with stone fragments (steinstrasse). Nephrostomy was performed in 5.3% of the total patient population and in 29% of the patients with stones measuring 2.5 cm or more. Only 1.8% of the patients with calculi smaller than 2.5 cm required radiologic intervention. When the obstructed collecting system could not be crossed with conventional angiographic techniques, the stone fragments were removed through a percutaneous nephrostomy tract either by flushing or by suctioning with a pulsating water jet.     

Optimizing gallbladder stone lithotripsy: an international survey.

Rates of stone clearance with extracorporeal shock wave cholecystolithotripsy (biliary lithotripsy [BL]) initially reported by European groups were encouraging. An American multicenter BL study (the Dornier National Biliary Lithotripsy Study [DNBLS]) did not reproduce these results. The BL treatment strategies and 6-month stone clearance rates of six leading European and Japanese centers were compared with those of DNBLS. All foreign centers used adjuvant oral chemolitholysis and greater shock wave energies from the same lithotriptor as that in DNBLS. Six months after BL, the stone clearance rates at all six centers were higher than those of DNBLS. There were no significant differences in complication rates between centers. These findings suggest that the poor results of DNBLS were chiefly due to the use of low kilovoltage and few BL sessions. Increased energy levels and a fragment size end point of less than 5 mm optimize BL. Despite the popularity of laparoscopic cholecystectomy, BL can be recognized as a successful treatment alternative for patients with a low burden of radiolucent stones.     

经皮肾镜大功率钬激光碎石术治疗复杂性肾结石疗效分析

目的：观察对复杂性的肾结石患者予以微造瘘下经皮肾镜行钬激光碎石的临床效果。方法自2008年11月～2012年11月以来,治疗的136例复杂性的肾结石患者临床资料进行回顾性分析。结果118例患者一期行单通道的碎石取石：在术后的5-7天予以泌尿系平片的复查,其中108例结石达到一次取净,其一期清石率约为79.4％（108/136）,其余10例为残留的小结石,予以体外的震波碎石。4例行中转开放式手术：其中2例患者术中出血较明显,以致视野模糊,经剥皮鞘后压迫5 min即好转,而继续操作却仍见出血,遂决定予以二期手术,而患者家属则要求实施开放式手术取石;其中2例由于通道迷失予以再次穿刺,但失败后中转为开放式手术。14例由于结石残留的较多行二期的碎石或者取石。其手术时间为105～220 min,（119.8＆#177;40.5）min。其术后住院为8～13天,（11.5＆#177;1.8）天。全部患者均未予双通道以及多通道的取石,均未出现肠管损伤或者胸膜损伤等临床并发症,均未出现穿刺失败,均未出现术中以及术后的大出血,没有输血,并且无一例出现术后的感染。136例经随访6～30个月,（19.5＆#177;8.5）月,有6例出现结石复发,经体外的震波碎石后均治愈。结论对复杂性的肾结石患者予以微造瘘下经皮肾镜行钬激光碎石,不仅高效安全,而且具有创伤小,与出血少,以及恢复快,和结石的清除率高等优点。     

Visibility of gallstone fragments at US and fluoroscopy: implications for monitoring gallstone lithotripsy

To assess the value of ultrasound (US), fluoroscopy, and spot radiography in the detection, counting, and measurement of gallstone fragments during lithotripsy, in vitro visibility studies were conducted on fragments from 20 stones. Fluoroscopic visibility was evaluated during and after lithotripsy on 185 fragments placed in an anthropomorphic phantom. Three US experiments were performed on the fragments to study the visibility of fragments as a function of size, the accuracy of the count with large numbers of fragments, and the ability of observers to detect and count fragments larger than both 4 mm and 5 mm. With fluoroscopy, fragment detection rates ranged from 20% (fragments larger than 2.5 mm) to 80% (fragments larger than 4.5 mm). With US, all fragments larger than 1.5 mm were detected, and US was significantly better than fluoroscopy and spot radiography for detection of fragments 2.5 mm or smaller. US was also more accurate than fluoroscopy (11% vs 59% error) in the assessment of the number of fragments. When fragments larger than 4 mm or 5 mm were being counted with US, 92% of the fragments were visualized. The results suggest that US is more accurate for monitoring gallstone lithotripsy than fluoroscopy or spot radiography.