Proximal Stone Migration Research Articles

The Ureteral Stone Cone is A Useful Device for the Prevention of Calculi Retropulsion during Holmium Laser Lithotripsy for Proximal and Mid-Ureteric Stones. A Nigerian Experience

Background: Retropulsion and stone fragment migration is a problem with lithotripsy especially for proximal and mid-ureteric calculi during ureteroscopy, leading to increased operative time, costs, and additional procedures. To overcome this drawback, many strategies have been developed, one of which is the use of anti-retropulsion devices like the stone cone. Objective: To describe our initial experience with the use of the stone cone during holmium laser lithotripsy in a patient with proximal and mid-ureteric stone for preventing retropulsion. Method: This is a retrospective study carried out on six consecutive patients with proximal with uncommon proximal ureteric stone over a 2year period ureteric stone. TPatients with distal ureteric stone were excluded. The Boston Scientific Stone Cone Nitinol Retrieval Coil was passed beyond the stone and deployed under fluoroscopy to prevent proximal stone and fragment migration. Holmium laser lithotripsy was then carried out. The fragments were removed with graspers and the stone cone was then removed. A double J stent was passed in all cases for about two to a month week and removed. The total operating time was noted. The data on the patient’s age, sex, stone size, Hounsfield, and stone clearance was analyzed using SPSS version 20. Results: There were six patients, five male, and one female with a mean age of 37.5years with an age range between 27 – 54years. The stone sizes ranged from 7-15mm with a mean dimension of 11.17mm. The Hounsfield of the stones ranged from 539 to 1171HU with a mean of 765.5HU. The operating time ranged from 55 – 90minutes with a mean of 67.5minutes. None had retropulsion with 100% stone clearance. Conclusion: The stone cone is a safe device and is useful during ureteroscopy and lithotripsy for mid-and proximal ureteric stone in preventing retropulsion and improving stone clearance.

Study of the outcome on ureteroscopic lithotripsy in patients with upper ureteric calculi: a descriptive study

Background: Ureteric calculi are one of the most common cause of abdominal pain in the emergency room. There are several options for the management of ureteric stones. Ureterorenoscopy and lithotripsy is the commonly used modality because it is less morbid and invasive, but the drawback is proximal stone migration which leads to persisting symptoms and increased costs. The aim of this study is to use an anti-retropulsion device to reduce the rate of proximal stone migration.Methods: This description study was conducted in Sree Gokulam Medical college from December 2014 to December 2015, on 75 consecutive patients who had ureteric stones, of ages 20-60 who were willing to give consent. All patients underwent ureteroscopy and lithotripsy and in those patients from who anti-retropulsion device could not be manipulated proximal to the stone lithotripsy alone was done. Both groups were compared for procedure time, post-operative symptoms and stone free rates.Results: The average time taken for the procedure with anti-retropulsion device was 45 minutes whereas in the other group was 72 minutes. 48 (96%) of patients using the device were symptom free and 48 (96%) patients had no symptoms after the procedure.Conclusions: The use of a anti retropulsion device can significantly reduce proximal stone migration, so thereby reducing further procedures and costs.

Prevention of stone retropulsion during ureteroscopy: Limitations in resources invites revival of old techniques

ABSTRACT Objective To compare a modified technique using the Dormia basket vs Stone Cone for stone entrapment to avoid proximal stone migration during ureteroscopic pneumatic lithotripsy of ureteric stones. Patients and methods Our study included all patients with ureteric stones of <15 mm who underwent ureteroscopic pneumatic lithotripsy from January 2015 to September 2018. The study had two arms that were conducted over two consecutive periods; the first included 72 patients in whom we used the Stone Cone (Group 1) and the second included 86 patients in whom we started to use a Dormia basket with a modification (Group 2) to guard against proximal stone migration. Results Both groups were comparable for gender, age, and stone characteristics. Lower ureteric stones were the most prevalent as they represented 62.5% and 60.5% in groups 1 and 2, respectively; while upper ureteric stones were respectively found in 16.7% and 17.4%. Chemical stone analysis revealed that calcium oxalate stones were most predominant accounting for 51.3% and 51.1% in groups 1 and 2, respectively. Most of the stones were radio-opaque stones representing 57% and 58.1% in groups 1 and 2, respectively. There was a significant difference in operative time, with a mean (SD) operative time was 50.9 (11.2) in Group 1 vs 58.3 (12.4) min in Group 2 (P < 0.001). The success rate, defined as no retropulsion of stone fragments, was 97.7% in Group 2 vs 91.7% in Group 1 (P < 0.01). Complications were minor and comparable between the groups. There was no difference in hospital stay between the groups, but the cost assessment favoured Group 2. Conclusion We found that our modified-basket stone entrapment technique compared favourably with the Stone Cone to guard against stone retropulsion during ureteroscopic pneumatic lithotripsy. Our modification to the basket was found to be feasible, efficient, safe, reproducible and cost-effective in preventing proximal stone migration. This procedure is particularly suitable in cost-limited environments.

106 - Antegrade irrigation during retrograde ureteroscopy – an efficient method to prevent proximal stone migration

106 - Antegrade irrigation during retrograde ureteroscopy – an efficient method to prevent proximal stone migration

The \u201cGuidewire-Coil\u201d-Technique to prevent retrograde stone migration of ureteric calculi during intracorporeal lithothripsy

BackgroundStone retropulsion represents a challenge for intracorporeal lithotripsy of ureteral calculi. The consequences are an increased duration and cost of surgery as well as decreased stone-free rates. The use of additional tools to prevent proximal stone migration entails further costs and risks for ureteral injuries. We present the simple technique of using a coil of the routinely used guidewire to prevent stone retropulsion.MethodsWe retrospectively evaluated all patients with mid-to-proximal ureteral stones in 2014, which were treated by ureteroscopic lithotripsy (Ho: YAG and/or pneumatic lithotripsy). The preoperative stone burden was routinely assessed using low dose CT scan (if available) and/or intravenous pyelogram.ResultsThe study population consisted of 55 patients with 61 mid-to-proximal calculi. Twentyseven patients underwent semirigid ureterorenoscopy using the “Guidewire-Coil-Technique”, the second group (n = 28) served as control group using the guidewire as usual. There has been a statistically significant reduction of accidental stone retropulsion (2/27 vs. 8/28, p < 0.05) as well as a decreased use of auxiliary procedures (p < 0.05) compared to the control group. No difference was observed in operative time. One ureteral injury in the control group required a prolonged ureteral stenting.ConclusionThe “Guidewire-Coil-Technique” is a simple and safe procedure that may help to prevent proximal calculus migration and therefore may increase stone-free rates without causing additional costs.

Ureteroscopic Lithotripsy; Retrospective Review of Mid and Lower Ureteric Stones- its Results and Complications

Purpose: To observe efficacy and complications of ureteroscopic lithotripsy in the treatment of mid and lower ureteric stones. The placement of DJ Stent was also compared for their beneficial role or otherwise. Materials and Methods: The medical records of 268 patients who underwent ureteroscopic lithotripsy (URSL) by a single surgeon from January 2010 December 2013 were reviewed retrospectively. All adult patients of mid and lower ureteric stones (10-22mm) were included in this study. Group I (n=98) patients had no DJ stent while Group II (n=96) patients had DJ stent due to prolong procedure. Group III (n=74) patients had DJ stent placed due to complications during the procedure or due to large volume of fragments that are left without retrieval after fragmentation. 28 patients required extracorporeal shockwave lithotripsy as during the procedure these patients had proximal stone migration. Results: The results were analyzed on aspects of stone clearance, hospital stay, complications and patient compliance. 80 patients in Group I, 82 patients in Group II and 42 patients in Group III completed the procedure in single session. The stone clearance at one week for mid ureteric stones in Group I (89.78%), Group II (91.67%), and Group III (91.89%) and in lower ureteric stones clearance was in Group I (97.96%), Group II (96.88%) and in Group III (95.95%). At one month 100% stone clearance was seen in all the three groups. The stented group had more complications than the non stented group. Conclusion: Ureteroscopic lithotripsy has gained wide acceptance worldwide and is an established technique for lower and mid ureteric calculi when patient demands single session removal of stone and alleviation of symptoms. Routine placement of DJ stent should be discouraged which has more complications as compared to non-stented patients.

Effect of ureteric stone location on the success rate of ureteroscopic Holmium laser lithotripsy

Background: Ureteral stone can cause obstructive uropathy and subsequent deterioration of renal function. There are four treatment options for ureteral calculi: lithotripsy, ureteroscopy, laparoscopic ureterolithotomy, and open stone surgery. Holmium YAG laser is an excellent intracorporial lithotripter for all kinds of stones. Accordingly, there is steady increase in number of ureteroscopic laser lithotripsy operations in the managmant of Ureteral stone.&#x0D; Objectives: this study was designed to demonstrate the effect of ureteric stone location on the success rate of ureteroscopic Holmium laser lithotripsy in the management of ureteric stones.&#x0D; Patients and Methods: Ninety middle-aged patients of either sex (35.9 ± 10.8 years) with ureteric stone (9.5 ± 3 mm) were treated with semiregid ureteroscopy using Holmuim: YAG laser as an intracorporial lithotripter. In 32 patients (35%) the stone were located in the lower ureter, 22 patients (24%) in middle ureter and in 36 patients (40%) in the upper ureter. Then all the patients were followed up on day 1 and 4 weeks for clearance of stone by plain abdominal radiography and abdominal ultrasonography.&#x0D; Results: the stone free rates 4 weeks after the treatment were 66% for upper, 75 % for middle and 87.5% for lower ureteric stones. In 12 patients (13%)cannot be possible to reach the stone, six patients (6.6 %) had proximal stone migration and treated later on by extracorporeal lithotripsy after double-J stent placement. Ureteral perforation occurred in 7 patients (7.7%), all managed by double-J stent placement except 1patient needed an open surgical treatment..&#x0D; Conclusion: YAG laser lithotripsy is efficacious modality of treatment for ureteric stones especially in lower ureter and it is a safe and technically feasible and in early experience, it is preferred to start with more distal stones.

Categorization of intraoperative ureteroscopy complications using modified Satava classification system

To review our experience with ureteroscopy (URS) in the treatment of ureteral calculi and stratify intraoperative complications of URS according to the modified Satava classification system. We performed a retrospective analysis of 1,208 patients (672 males and 536 females), with a mean age of 43.1 years (range 1-78), who underwent ureteroscopic procedures for removal of ureteral stones. Intraoperative complications were recorded according to modified Satava classification system. Grade 1 complications included incidents without consequences for the patient; grade 2 complications, which are treated intraoperatively with endoscopic surgery (grade 2a) or required endoscopic re-treatment (grade 2b); and grade 3 complications included incidents requiring open or laparoscopic surgery. The stones were completely removed in 1,067 (88.3%) patients after primary procedure by either simple extraction or after fragmentation. The overall incidence of intraoperative complications was 12.6%. The most common complications were proximal stone migration (3.9%), mucosal injury (2.8%), bleeding (1.9%), inability to reach stone (1.8%), malfunctioning or breakage of instruments (0.8%), ureteral perforation (0.8%) and ureteral avulsion (0.16%). According to modified Satava classification system, there were 4.5% grade 1; 4.4% grade 2a; 3.2% grade 2b; and 0.57% grade 3 complications. We think that modified Satava classification is a quick and simple system for describing the severity of intraoperative URS complications and this grading system will facilitate a better comparison for the surgical outcomes obtained from different centers.

Simultaneous saline irrigation during retrograde rigid ureteroscopic lasertripsy for the prevention of proximal calculus migration.

In this paper, we analyze the clinical efficacy of a simultaneous saline irrigation method in treating upper-mid ureteral stone migration and evaluate its effectiveness during ureteroscopic lasertripsy. We prospectively evaluated 78 patients with a total of 95 upper-mid ureteral stones, which were treated with holmium:YAG lasertripsy. These patients were randomized into 2 groups. In Group 1 (39 cases with 44 ureteral stones), conventional ureteroscopic lasertripsy was performed. In Group 2, (39 cases with 51 ureteral stones), the simultaneous saline irrigation method was used during lasertripsy. There was no significant difference between the groups with regards to stone site, size or state of the upper urinary tract by spiral computed tomography or excretory urography. Data were analyzed regarding stone migration, lengths of time, and ureteral clearing for various stages of each procedure. One patient in Group 2 (2%) experienced upward stone migration, while this occurred in 8 patients in Group 1 (20%). The operative time in Group 1 ranged from 35 to 55 minutes (mean: 44.8 ± 5.3), while in Group 2 it ranged from 40 to 69 minutes (mean: 50.4±3). There was no significant different in the operative times between the two groups (p < 0.05). Ureteral perforation, urinoma and urosepsis were not seen in both groups. The simultaneous saline irrigation method demonstrated a statistically significant advantage over conventional methods. The operation can be performed persistently under clear vision, and since the stones cannot move upward, fragmented portions are easily flushed out. Our data suggest that this method is simple, safe and effective in preventing proximal stone migration during ureteroscopic lasertripsy.

A comparison of Stone Cone versus lidocaine jelly in the prevention of ureteral stone migration during ureteroscopic lithotripsy.

Intracorporeal lithotripsy modalities and stone removal devices have been created to facilitate endoscopic management of ureteral stones. These devices, along with improved techniques, have resulted in stone-free rates greater than 95% with low morbidity. However, problems remain that preclude consistent 100% stone-free rates with endoscopic treatment of ureteral calculi. Retrograde migration during ureteroscopic procedures remains a significant problem. The aim of this study was to compare the Stone Cone device and instillation of lubricating lidocaine jelly as two methods to prevent retrograde stone migration during ureteroscopic lithotripsy. This study included patients suffering from ureteral stones that were treated with intracorporeal lithotripsy using the pneumatic Lithoclast. These patients were divided into two groups. In group I, the Stone Cone device was used, while in group II, lidocaine jelly 2% concentration was used. This study included 40 patients with a mean age of 38.6 ± 9.3 years (20 patients in each group). There was no significant difference between the groups with regards to stone site, size or state of the upper urinary tract by excretory urography. The pneumatic Lithoclast allowed successful fragmentation of all calculi into small fragments. Upward stone migration did not occur in patients in the Stone Cone group, while in the lidocaine jelly group it occurred in three patients (15%). The operative time in the Stone Cone group ranged between 30 and 55 minutes (mean, 41.8 ± 5.3), while in the lidocaine jelly group it ranged between 40 and 71 minutes (mean, 51.4 ± 3.4), and this difference was statistically significant (p < 0.05). The Stone Cone is safe and efficient in preventing proximal stone migration during ureteroscopic pneumatic lithotripsy. It maintained continuous ureteral access and demonstrated a statistically significant advantage over the lidocaine jelly in terms of proximal stone migration, operative time, and the need for auxiliary procedures.

A Randomized Prospective Controlled Study for Assessment of Different Ureteral Occlusion Devices in Prevention of Stone Migration During Pneumatic Lithotripsy

To compare the safety and efficacy of two different ureteral occlusion devices (stone cone and entrapment net) in preventing retrograde stone migration during ureteroscopic pneumatic lithotripsy. Proximal migration of stone fragments during ureteroscopic lithotripsy is a common problem, especially when the pneumatic lithotripter is used for stone fragmentation. A total of 195 patients with proximal ureteric stones were prospectively randomized into one of three groups in this study, with 65 patients in each group. In group I, the Stone Cone was used as a ureteral occlusive device; in group II, the N-Trap was used; and in group III (control group), the patients underwent pneumatic lithotripsy without any ureteral occlusive device. The ureteroscopic procedure was completed successfully in 180 patients; 63 patients in group I, 59 patients in group II, and 58 patients in group III. Patients in group I showed significantly lower incidence of stone migration compared with the other 2 groups (P <.05). Both ureteral occlusive devices significantly lowered the incidence of residual fragments (>3 mm), ureteral trauma, operative time, and the need for ureteral stenting compared with control group. The stone-free rate at 3 weeks was 95.24%, 83.05%, and 72.41% in groups I, II, and III, respectively. The patients in group I had a statistically significant stone-free rate compared with the other two groups (P <.05). Auxiliary procedures were required in 3 (4.76%), 10 (16.94%), and 16 cases (27.58%) in groups I, II, and III, respectively. The use of Stone Cone or N-Trap is valuable during ureteroscopic pneumatic lithotripsy for treatment of proximal ureteral stones. Both devices significantly diminish residual fragments, the incidence of ureteral wall trauma, and the need for the auxiliary procedure. However, the stone cone was more effective in preventing proximal stone migration and the subsequent stone-free rate.

Systematic Evaluation of Ureteral Occlusion Devices: Insertion, Deployment, Stone Migration, and Extraction

To compare 4 ureteral occlusion devices in terms of insertion force, maneuverability, radial dilation and extraction forces, ability to prevent stone migration, and tip stiffness. The devices tested were the PercSys Accordion, Microvasive Stone Cone (7 and 10 mm), and Cook N-Trap. Using a ureteral model with an artificial stone in place, the insertion force, number of attempts, and time to pass the impacted stone were measured. Using a Teflon block model, radial dilation and extraction and axial extraction force were measured with a load cell. Holmium lithotripsy was performed in the ureteral model with a canine stone in place to test the ability of the devices to prevent stone migration. In a similar model, the force applied to retrieve the canine stone was measured. The stiffness of the tip was measured as the force to compress a 5-mm length of the tip in a clamp-clamp configuration on a linear motion stage driven by a stepper motor with a resolution of 8-mum/step. The devices were significantly different statistically from each other in terms of insertion force, number of attempts and time to pass the impacted stone, radial dilation, radial extraction, and axial extraction force in the Teflon block model. No proximal migration of the stones occurred with any of the devices. The devices were similar in terms of preventing proximal stone migration, force applied to retrieve stones, and tip stiffness. The differences in the physical characteristics of stone migration devices might help to predict their safety and efficacy in clinical use.

Evaluation of a Novel Temperature-Sensitive Polymer for Temporary Ureteral Occlusion

Proximal stone migration during ureteroscopic procedures increases operative time and risk. This study was designed to evaluate the ability of a new temperature-sensitive polymer to prevent proximal stone migration during ureteroscopic procedures. Porcine urinary systems were harvested en bloc. The volume of gel needed to occlude the ureter, time to achieve a solid state, length of ureter filled, and pressure needed to dislodge the gel from the ureter were recorded. Radio opacity of the polymer was evaluated. Endoscopic laser lithotripsy was the performed after deploying the urologic polymer, and, after gel application and stone manipulation, all ureters were examined for histologic changes. At 36.7 degrees C, 0.5 mL and 1 mL of polymer sufficiently occluded the ureter. Both amounts solidified in 25 to 40 seconds. The mean length of ureter occluded was 56.3 mm, and the mean pressure needed to dislodge the polymer was 159.2 mm Hg. The polymer was radiopaque and did not cause histologic alterations in the ureter. Proximal migration of stone fragments was not observed during any of the procedures performed. Our in vitro study indicates that this radiopaque, thermosensitive polymer is able to transiently occlude the ureter without damaging the urothelium while withstanding the pressure of ureteroscopic irrigation, stone motion, and laser energy.

Does stone dimension affect the effectiveness of ureteroscopic lithotripsy in distal ureteral stones?

To investigate whether stone dimension is a restrictive factor for ureterorenoscopic procedures. A group of 416 patients who had undergone ureterorenoscopic pneumatic lithotripsy (URS-PL) for lower ureteral stones between January 1999 and June 2006 in our clinic had been evaluated retrospectively. Two hundred and seventy (270, 64.9%) patients were men and 146 (35.1%) were women. The mean age of the patients was 36.61 (+/- 12.43) years. Patients were grouped according to stone dimension; 193 patients with stones smaller than 1 cm being group 1 and 223 patients with stones > or = 1 cm in dimension being group 2. Stone-free rate, operative time and rate of complications of the groups were compared. Pearson's correlation test, chi2 test, Fischer's exact test and Student's t-test were used for the statistical analysis. The p value was accepted as being meaningful if p < 0.05. For group 1, the mean operative time was 39.19 (+/- 18.33) min. Proximal stone migration in five and false passage formation in three patients was observed. Three patients were stone-free after a second session of URS-PL. The cumulative stone-free rate was 97.4% (188/193). For group 2, the mean operative time was 48.5 (+/- 11.31) min. About 208 (93.27%) patients were stone-free after the first session and an additional eight patients became stone-free after the second session of URS-PL. False passage, ureteral perforation, ureteral avulsion and stricture were observed in four, six, one and one patients, respectively. No proximal stone migration was observed. The cumulative stone-free rate was 96.86% (216/223). The effectiveness of ureterorenoscopy (URS) in the treatment of distal ureteral stones was independent of stone dimension. However, the operative time was longer and the rate of perforation was higher in stones with a diameter > or = 1 cm. On the other hand, the migration rate was higher in stones < 1 cm in diameter. Generally speaking, there was no meaningful effect of stone dimension on complication rates.

Ureteroscopic Holmium Lasertripsy for Treatment of Impacted Ureteral Calculi

Objective: To evaluate the effi cacy and safety of Holmium: YAG laser lithotripsy for the treatment of impacted ureteral stones. Patients and Methods: From January 2000 to January 2007, 150 patients (105 males and 45 females) with impacted ureteral stones were treated at the Urology Department of the Assiut University Hospital, Assiut, Egypt. Their mean age was 36 years (range 20 to 66 years). The mean duration of stone impaction was 4.6 months. The patients were managed via the retrograde endoscopic approach using small caliber (6.9 F rigid and 7.5 F fl exible) ureteroscopes and the Holmium:YAG laser lithotriptor. Results: Out of 150 ureteral stones, 144 (96%) were completely fragmented with a single endoscopic procedure. Proximal stone migration occurred in two cases, and the stones were treated by extracorporeal shock wave lithotripsy (ESWL). Intra-operative ureteral perforation occurred in 4 cases and was managed by open surgical treatment. Endoscopic observation revealed infl ammatory polyps at the site of impaction in 75 patients and a stricture adjacent to the stone in 20 cases. Conclusion: Holmium: YAG laser lithotripsy may be considered an effective fi rst-line therapy for chronically impacted ureteral stones, which are frequently associated with chronic infl ammation, polyps and strictures. It is quite safe and it avoids the futile repetition of ESWL and problems caused by a prolonged passage of stone fragments. Keywords : Ureteroscopy, holmium laser, impacted ureteral stone African Journal of Urology Vol. 13 (4) 2007: pp. 262-266

Efficacy of Dretler Stone Cone in the Treatment of Ureteral Stones with Pneumatic Lithotripsy

Introduction: Ureteroscopic pneumatic lithotripsy has been used to treat ureteral calculi for more than 10 years. Owing to its low price and high degree of effectiveness, it has become the most popular ureteroscopic lithotripsy device in use worldwide. The major limitation of the technique is the occurrence of proximal fragment migration during intracorporeal lithotripsy. The Dretler Stone Cone is a new device developed to prevent stone migration during ureteroscopic lithotripsy. The aim of this study was to assess the efficacy and safety of this device during ureteroscopic pneumatic lithotripsy. Patients and Methods: Twenty-three consecutive patients having ureteral stones were treated with a 10-Fr semirigid ureteroscope, a Stone Cone™ Nitinol Retrieval Device, and a pneumatic lithotriptor. In all patients Stone Cones were placed under visual guidance through the working channel of the ureteroscope. Outcomes of this device were then compared with the outcomes of 23 previous patients with stones of similar sizes and locations who had undergone ureteroscopic pneumatic lithotripsy prior to the Stone Cone being available at our clinic. Results: All patients in the study group were stone-free after the procedure. No stone fragments were noted to migrate to proximal segments. Conclusions: The Dretler Stone Cone effectively prevents proximal stone migration and facilitates stone fragmentation during pneumatic lithotripsy with no risk of ureteral injury. It has only a small extra cost.

Extracorporeal Shockwave Lithotripsy and Intracorporeal Lithotripsy for Proximal Ureteric Calculi – A Comparative Assessment of Efficacy and Safety

Introduction: Extracorporeal shockwave lithotripsy (ESWL) is the treatment modality of choice of many urologists for proximal ureteric calculi. In this study, we compared the efficacy and safety of ESWL versus ureteroscopy with holmium laser lithotripsy for the treatment of this group of stones. Materials and Methods: Between May 1999 and October 2000, 50 patients had ESWL and another 51 patients underwent ureteroscopy with holmium laser lithotripsy for proximal ureteric calculi. The two groups were similar in age, sex ratio and stone size. ESWL was performed with the Dornier Compact lithotriptor whereas holmium laser lithotripsy was performed via retrograde ureteric access with a Wolf 7.5 Fr semirigid ureteroscope. Results: Ureteroscopy with holmium laser lithotripsy was significantly better in terms of the mean procedure time (56 min in ESWL; 25 min in ureteroscopy; P &lt;0.001) and the 1-month stone free rate (50% in ESWL; 80% in ureteroscopy; P = 0.001). The 3-month stone free rate was also higher for ureteroscopy (78% in ESWL; 90% in ureteroscopy) but this difference was not statistically significant (P = 0.09). Minor complications of steinstrasse (6%) occurred in ESWL and proximal stone migration (8%) occurred during ureteroscopy. Conclusion: Ureteroscopy with holmium laser lithotripsy is a viable and safe alternative to ESWL for the management of proximal ureteric calculi.

Open mini-access ureterolithotomy: the treatment of choice for the refractory ureteric stone?

To report the experience in one centre of the efficacy and safety of open mini-access ureterolithotomy (MAU) and to discuss relevant current indications. MAU was undertaken in 112 patients (mean age 38 years, range 26-57) between 1991 and 2001; the details and outcomes are reviewed. The mean (range) stone size was 12 (8-22) mm, with 30 stones in the upper, 69 in the mid- and 13 in the lower ureter. In 15 cases the stones were impacted and there were signs of infection in the proximal ureter. MAU was successful in 111 patients; the one failure was caused by proximal stone migration early in the series. The mean (range) operative duration was 28 (10-44) min and the hospital stay 42 (24-72) h; 33 patients were in hospital for 24 h, 72 for 48 h and seven for 72 h. The blood loss was minimal, at 50 (30-150) mL. The drain was removed after 5 (5-7) days. Patients reported using opioid or nonsteroidal anti-inflammatory analgesia for a mean of 4 (1-7) days after surgery. The mean time to resumption of work was 16 (8-35) days. MAU is a safe and reliable minimally invasive procedure; its role is mainly confined to salvage for failed first-line stone treatments but in selected cases, where a poor outcome can be predicted from other methods, it is an excellent first-line treatment.

The Dretler Stone Cone: A Device to Prevent Ureteral Stone Migration—The Initial Clinical Experience

Retrograde stone migration during ureteroscopic lithotripsy occurs in 5% to 40% of proximal and distal ureteral stone cases. This migration increases morbidity and the need for auxiliary procedures. The Dretler stone cone (Medsource, Norwell, Massachusetts) is a novel device to prevent proximal stone migration and facilitate fragment extraction during ureteroscopic lithotripsy. We assessed the safety and efficacy of the Dretler stone cone in the clinical setting and compared it prospectively with a conventional flat wire basket during ureteroscopy for ureteral calculi. To our knowledge we report the initial clinical use of the Dretler stone cone in 50 consecutive patients with ureteral calculi undergoing ureteroscopic extraction. Calculi were situated above the sacroiliac joint in 24 cases, over the sacroiliac joint in 15 and below the sacroiliac joint in 11. Pneumatic lithotripsy was done in 42 cases. In the remaining 8 cases ureteroscopic (3) or fluoroscopic (5) intact stone extraction was performed. The later 23 cases using the Dretler stone cone were prospectively compared with 20 of ureteroscopic intracorporeal lithotripsy using a standard flat wire basket. The Dretler stone cone was successfully placed in all 50 cases. In 41 patients it was placed via cystoscopy under fluoroscopic guidance, while 9 impacted stones required ureteroscopic placement. Six patients in whom the Dretler stone cone was used had residual fragments less than 3 mm. No patient required auxiliary procedures. In the prospective trial no patients in Dretler stone cone group had residual fragments greater than 3 mm. or required auxiliary procedures. However, in the flat wire basket group residual stones greater than 3 mm. were present in 6 cases (30%, p <0.001), while auxiliary procedures were required in 4 (20%, p <0.01). The Dretler stone cone represents a new generation of basketry that minimizes proximal ureteral stone migration and allows safe extraction of fragments during ureteroscopic lithotripsy. In our experience it is associated with a lower incidence of significant residual fragments and fewer auxiliary procedures than conventional flat wire baskets.