Safety of percutaneous renal cryoablation: an international multicentre experience from the EuRECA retrospective percutaneous database.

OBJECTIVE: To investigate the safety profile of percutaneous cryoablation of renal tumours < 7 cm, utilising data extracted from an international multicentre registry. MATERIALS AND METHODS: A retrospective review of all immediate and delayed complications from a multicentre database was performed and was categorised according to the Clavien-Dindo classification. Statistical analysis was performed for both overall complications (all Clavien-Dindo) and major complications (Clavien-Dindo 3 to 5). The following criteria were identified as potential predictive factors for complications: centre number, modality of image guidance, tumour size (≤ 4 cm vs. > 4 cm), number of tumours treated in the same session (1 vs. > 1) and tumour histology. RESULTS: A total of 713 renal tumours underwent ablation in 647 individual sessions. In 596 of the cases, one tumour was treated; in the remaining 51 cases, several tumours were treated per session. Mean lesion size was 2.8 cm. Fifty-four complications (Clavien-Dindo 1 to 5) occurred as a result of the 647 procedures, corresponding to an overall complication rate of 8.3%. The most frequent complication was bleeding (3.2%), with 9 cases (1.4%) requiring subsequent treatment. The rate of major complication was 3.4%. The only statistically significant prognostic factor for a major complication was a tumour size > 4 cm. CONCLUSION: Percutaneous renal cryoablation is associated with a low rate of complications. Tumours measuring more than 4 cm are associated with a higher risk of major complications. KEY POINTS: • Percutaneous kidney cryoablation has a low rate of complications. • Bleeding is the most frequent complication. • A tumour size superior to 4 cm is a predictive factor of major complication.

The effect of consultant outcome publication on surgeon behaviour: a systematic review and narrative synthesis.

Introduction Surgeon-specific outcome data, or consultant outcome publication, refers to public access to named surgeon procedural outcomes. Consultant outcome publication originates from cardiothoracic surgery, having been introduced to US and UK surgery in 1991 and 2005, respectively. It has been associated with an improvement in patient outcomes. However, there is concern that it may also have led to changes in surgeon behaviour. This review assesses the literature for evidence of risk-averse behaviour, upgrading of patient risk factors and cessation of low-volume or poorly performing surgeons. Materials and methods A systematic literature review of Embase and Medline databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Original studies including data on consultant outcome publication and its potential effect on surgeon behaviour were included. Results Twenty-five studies were identified from the literature search. Studies suggesting the presence of risk-averse behaviour and upgrading of risk factors tended to be survey based, with studies contrary to these findings using recognised regional and national databases. Discussion and conclusion Our review includes instances of consultant outcome publication leading to risk-averse behaviour, upgrading of risk factors and cessation of low-volume or poorly performing surgeons. As UK data on consultant outcome publication matures, further research is essential to ensure that high-risk patients are not inappropriately turned down for surgery.

Patient and disease factors predictive of adverse perioperative outcomes after nephrectomy.

INTRODUCTION: The aim of this study was to determine the patient and disease factors predictive of adverse perioperative outcomes after nephrectomy using the British Association of Urological Surgeons (BAUS) audit database. METHODS: All nephrectomies entered on the BAUS database for the year 2012 were included and ten patient or disease factors were selected for analysis. Logistic regression was used to calculate the area under the receiver operating characteristic curve (AUC) (0.5 = no better than chance, 1.0 = perfect prediction) for each variable and 500 bootstrap samples were used to determine variable selection. RESULTS: Data were captured for 6,031 nephrectomies in 2012. World Health Organization performance status (WHO-PS) (AUC: 0.733) and anaemia (AUC: 0.696) were the most significant predictors of 30-day mortality in univariate analysis. WHO-PS (AUC: 0.626) and anaemia (AUC: 0.590) also predicted complications classified as Clavien-Dindo grades III-V. Anaemia (AUC: 0.722) and clinical T stage (AUC: 0.713) predicted need for transfusion. CONCLUSIONS: Adverse perioperative outcomes after nephrectomy are predicted by clinical presentation with haematuria, poor WHO-PS and higher TNM (tumour, lymph nodes, metastasis) stage. This study used surgeon collected data as opposed to an administrative database, which may have advantages in terms of accuracy and breadth of data fields. These data form a basis for preoperative patient counselling and informed consent for nephrectomy. They can also be used as a standard against which surgeons and hospitals can compare their own results.

[The French linguistic validation of the Ureteric Stent Symptom Questionnaire (USSQ)]. / Validation en langue française du questionnaire << Ureteric Stent Symptom Questionnaire >> (USSQ).

PURPOSE: Translation and linguistic validation of the French version of the Ureteral Stent Symptom Questionnaire (USSQ). MATERIALS AND METHODS: A double-back translation of the original Ureteral Stent Symptom Questionnaire was performed. First, two urologists translated the English version in French. Then a first consensus meeting between the translators and a group composed with three urologists, one general practitioner and two nurses was achieved. Back-translation of this version was then done by professional translators (Nagpal, Paris) to ensure that no distortion was detected between the two questionnaires. Finally, a pilot test followed by an interview was carried out among two men and two women who had an indwelling ureteral stent. RESULTS: The consensus version is attached to the article. No difficulties were reported by the pilot population to comprehend or to complete this USSQ French version. CONCLUSION: This USSQ version - attached to the article - makes it possible for researchers among a French population to use this validated and internationally recognized tool that provides reproducible and measurable endpoints on tolerance of ureteral stents.

Extra-corporeal shock wave lithotripsy (ESWL) versus ureteroscopic management for ureteric calculi.

BACKGROUND: Ureteral stones frequently cause renal colic and if left untreated can cause obstructive uropathy. Extracorporeal Shock Wave Lithotripsy (ESWL) and ureteroscopy, with or without intracorporeal lithotripsy, are the two most commonly offered interventional procedures in these patients. ESWL treatment is less invasive but has some limitations such as a high retreatment rate and lack of availability in many centres. Advances in ureteroscopy over the past decade have increased the success rate and reduced complication rates. OBJECTIVES: To examine evidence from randomised controlled trials (RCTs) on the outcomes of ESWL or ureteroscopy in the treatment of ureteric calculi. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL in The Cochrane Library Issue 2, 2006), MEDLINE (1966 - March 2006), EMBASE (1980 - March 2006), reference lists of articles and abstracts from conference proceedings without language restriction. SELECTION CRITERIA: RCTs comparing ESWL with ureteroscopic retrieval of ureteric stones were included. Participants were adults with ureteric stones requiring intervention. Published and unpublished sources were considered. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data. Statistical analyses were performed using the random effects model and the results expressed as relative risk (RR) for dichotomous outcomes or weighted mean difference (MD) for continuous data with 95% confidence intervals (CI). MAIN RESULTS: Six RCTs (833 patients) were included. The stone-free rates were lower in the ESWL group (RR 0.84 95% CI 0.73 to 0.96). The retreatment rates were lower but not significant in the ureteroscopy group (RR 3.34 95% CI 0.82 to 13.62). The rate of complications was lower in the ESWL group (RR 0.48 95% CI 0.26 to 0.91). Length of hospital stay was less for ESWL treatment (MD -2.10 95% CI -2.55 to -1.64). AUTHORS' CONCLUSIONS: Ureteroscopic removal of ureteral stones achieves a higher stone-free state but with a higher complication rate and a longer hospital stay.

Microstructural and tensile properties of elastin-based polypeptides crosslinked with genipin and pyrroloquinoline quinone.

Elastin is an elastomeric, self-assembling extracellular matrix protein with potential for use in biomaterials applications. Here, we compare the microstructural and tensile properties of the elastin-based recombinant polypeptide (EP) EP20-244 crosslinked with either genipin (GP) or pyrroloquinoline quinone (PQQ). Recombinant EP-based sheets were produced via coacervation and subsequent crosslinking. The micron-scale topography of the GP-crosslinked sheets examined with atomic force microscopy revealed the presence of extensive mottling compared with that of the PQQ-crosslinked sheets, which were comparatively smoother. Confocal microscopy showed that the subsurface porosity in the GP-crosslinked sheets was much more open. GP-crosslinked EP-based sheets exhibited significantly greater tensile strength (P < or = 0.05). Mechanistically, GP appears to yield a higher crosslink density than PQQ, likely due to its capacity to form short-range and long-range crosslinks. In conclusion, GP is able to strongly modulate the microstructural and mechanical properties of elastin-based polypeptide biomaterials forming membranes with mechanical properties similar to native insoluble elastin.

Differential expression of two tropoelastin genes in zebrafish.

Elastin is the extracellular matrix protein responsible for properties of extensibility and elastic recoil in large blood vessels, lung and skin of most vertebrates. Elastin is synthesized as a monomer, tropoelastin, but is rapidly transformed into its final polymeric form in the extracellular matrix. Until recently information on sequence and developmental expression of tropoelastins was limited to mammalian and avian species. We have recently identified and characterized two expressed tropoelastin genes in zebrafish. This was the first example of a species with multiple tropoelastin genes, raising the possibility of differential expression and function of these tropoelastins in elastic tissues of the zebrafish. Here we have investigated the temporal expression and tissue distribution of the two tropoelastin genes in developing and adult zebrafish. Expression was detected early in skeletal cartilage structures of the head, in the developing outflow tract of the heart, including the bulbus arteriosus and the ventral aorta, and in the wall of the swim bladder. While the temporal pattern of expression was similar for both genes, the upregulation of eln2 was much stronger than that of eln1. In general, both genes were expressed and their gene products deposited in most of the elastic tissues examined, with the notable exception of the bulbus arteriosus in which eln2 expression and its gene product was predominant. This finding may represent a sub-specialization of eln2 to provide the unique architecture of elastin and the specific mechanical properties required by this organ.

Patterns of proopiomelanotropin and proopiocortin gene expression and of immunohistochemistry for gonadotropin-releasing hormones (lGnRH-I and III) during the life cycle of a nonparasitic lamprey: relationship to this adult life history type.

There are two adult life history types among lamprey species, nonparasitic and parasitic, with the former commencing the final interval of sexual maturation immediately after metamorphosis. There are no extensive studies that directly compare hormone profiles during the life cycles of nonparasitic and parasitic lamprey species, yet such data may explain differences in development, reproductive maturation, and feeding status. The present study uses immunohistochemistry to show the life cycle profiles for gonadotropin-releasing hormones (GnRH-I and -III) in the brain of the nonparasitic species, the American brook lamprey, Lampetra appendix, for comparison with the extensive, published, immunohistochemical data on these hormones in the parasitic species, the sea lamprey, Petromyzon marinus. The complete cDNAs for the two lamprey prohormones, proopiocortin (POC), and proopiomelanotropin (POM), were cloned for L. appendix and both nucleotide and deduced amino acid sequences were compared with those previously published for P. marinus. The POC and POM cDNAs for both species were used in expression studies, with Northern blotting, throughout their life cycles. Although GnRH-I and -III immunohistochemistry revealed a similar distribution of immunoreactive cells and fibers in the two species during the life cycles, a qualitative evaluation of staining intensity in L. appendix, implied early activity in the brains of metamorphosis of this species, particularly in GnRH-I. GnRH-III seems to be important in larval life and early metamorphosis in both species. A novel feature of this immunohistochemical study is the monthly observations of the distribution and relative intensity of the two GnRHs during the critical period of final sexual maturation that lead to spawning and then the spent animal. L. appendix POC and POM nucleotide sequences had 92.9 and 94.6% identity, respectively, with P. marinus POC and POM and there was an earlier increase in their expression during metamorphosis and postmetamorphic life. Since there was some correlation between the timing of metamorphic development, gonad maturation, and brain irGnRH intensity with POC and POM expression in L. appendix, it was concluded that these prohormones yield posttranslational products that likely play a substantial role in development and maturation events that lead to the nonparasitic adult life history of this species.

Our experience with retroperitoneal and transperitoneal laparoscopic pyeloplasty for pelvi-ureteric junction obstruction.

OBJECTIVE: Laparoscopic dismembered pyeloplasty has been quoted to have equivalent success rates to the traditional open procedure in the treatment of pelvi-ureteric junction obstruction (PUJO). The aim of this study was to report our experience with laparoscopic pyeloplasty. PATIENTS AND METHODS: All patients with PUJO are entered into a database to record patient, operative and post-operative details. Over an eleven-year period, 176 procedures were performed. Eighty-three procedures were dismembered laparoscopic pyeloplasties, of which two retroperitoneal procedures were converted to open. The first 17 procedures were performed via the retroperitoneal approach and the following 66 via the transperitoneal route. Thirty-one procedures were open pyeloplasty. RESULTS: The retroperitoneal group had a mean follow up of 35 (16-66) months. Five patients (33%) developed recurrent symptoms with evidence of obstruction seen on the renogram within 4 months and required further surgery. The transperitoneal group had a mean follow up of 15 (3-38) months. Five patients were classified as failures (mean time to failure 4.6 months) resulting in a success rate of 92% for the transperitoneal route. Both groups had a mean post-operative hospital stay of 3.6 days. Open pyeloplasty at our institution has a success rate of 88% at a mean follow up of 85 months (range 3-260 months) and a mean length of post-operative stay of 6 days. CONCLUSION: Overall our success rate following laparoscopic pyeloplasty is 88%. However, our preferred approach is transperitoneal, which is associated with a success rate of 92%. This is equivalent, if not better than that seen following open pyeloplasty with the additional benefits of reduced hospital stay and time to recovery. There are many possible explanations for this difference in success rates between approaches, however equivalent results are reported in the literature and therefore the learning curve is likely to be the major factor in this series.

Evidence for the use of silver-alloy-coated urethral catheters.

Catheter-associated urinary tract infections (CAUTIs) are a common occurrence and are associated with increased patient morbidity and mortality. In addition, they delay patient discharge from hospital, substantially increase hospital costs and promote the emergence of resistant organisms. Any intervention resulting in a decrease in the incidence of CAUTIs would have a significant impact on patient quality of life and hospital costs. By reviewing the current literature, it can be seen that the use of silver-alloy-coated hydrogel catheters can reduce CAUTIs by up to 45%. Despite reducing CAUTIs in most hospital situations, the greatest reduction is seen in postoperative patients, intensive care unit patients and burns patients.

Cost analysis of flexible ureterorenoscopy.

OBJECTIVE: To assess the costs of flexible ureterorenoscopy. MATERIALS AND METHODS: Data were collected prospectively for 100 cases using a new flexible ureteroscope (DUR8, Circon ACMI, Stamford, USA), including the indications for flexible ureterorenoscopy, use of laser probes, disposable instrumentation, and the cost and timing of ureteroscope repair. RESULTS: Of the 100 procedures 68 were for stone disease, 21 for known or suspected transitional cell carcinoma (TCC), six were diagnostic only and five were for pelvi-ureteric junction obstruction. The ureteroscope was repaired after the 29th and 88th cases. The ability of the ureteroscope to deflect was maintained throughout. At the time of purchase the ureteroscope was listed at pound 15 000 and each repair/exchange currently costs pound 4200, thus the total expenditure on the ureteroscope was pound 23 400. Total expenditure on ancillary equipment was pound 28 727, of which pound 22 927 was on disposables and pound 5800 on 10 laser probes. CONCLUSION: In this series the costs of the ancillary equipment exceeded the purchase and maintenance of the ureteroscope, and we expect this trend to continue in the long term. The advent of more durable ureteroscopes may ultimately reduce the frequency of costly repairs. The cost of disposables should be considered in planning the budget.

A comparison of aspiration and sclerotherapy with laparoscopic de-roofing in the management of symptomatic simple renal cysts.

OBJECTIVES: To present the results of a minimally invasive treatment of symptomatic simple renal cysts, and to propose an algorithm for their management. PATIENTS AND METHODS: Seventeen patients presenting with suspected symptomatic simple renal cysts were referred for trial aspiration; 16 presented with loin pain and one with a flank mass. If the cyst and symptoms recurred after a temporary response, they were managed by re-aspiration with sclerotherapy using 95% ethanol, or by laparoscopic de-roofing of the cyst. RESULTS: Of the 17 patients referred, one failed to respond to aspiration and was excluded from further analysis. Three patients had sustained pain relief from simple aspiration alone, 13 required further treatment for symptom relapse, of whom six had aspiration and sclerotherapy, and seven had laparoscopic de-roofing. After a mean follow-up of 17 months, pain had recurred in all five patients originally presenting with pain and managed by sclerotherapy, and the patient who presented with a painless mass from a large cyst also developed pain after sclerotherapy. In contrast, the subsequent seven patients managed by laparoscopic treatment are pain-free at a mean follow-up of 17.7 months. CONCLUSION: Evaluation including a diagnostic aspiration is essential to diagnose a symptomatic cyst. When treatment is indicated, laparoscopic de-roofing appears to be more effective than sclerotherapy.

Endoluminal ultrasonography before retrograde endopyelotomy: can the results match laparoscopic pyeloplasty?

OBJECTIVE: To present the results of endopyelotomy using endoluminal ultrasonography (EUS) to identify crossing vessels, as the success rates of endopyelotomy are generally lower than pyeloplasty, especially in patients with crossing vessels. PATIENTS AND METHODS: Forty-one consecutive patients who underwent EUS before a planned retrograde endopyelotomy were analysed retrospectively. EUS was used to direct the endopyelotomy incision for patients with crossing vessels. Treatment was considered successful if the patient was asymptomatic and unobstructed or improved on renography. The results were compared to those from 18 patients treated by laparoscopic pyeloplasty, some of whom had undergone EUS. RESULTS: Crossing vessels were identified in 27 of the 41 patients (66%). Primary treatment consisted of endopyelotomy for 26 patients and laparoscopic pyeloplasty for 15. The overall success rate for 24 endopyelotomy patients with an adequate follow-up (mean 19 months) was 71%, with more success in patients with no crossing vessels (11 of 13 (85%) vs six of 11 (55%)). Of the 18 patients treated by laparoscopic pyeloplasty (mean follow-up 15.1 months) 17 were successful. CONCLUSION: The results for endopyelotomy were disappointing in patients with crossing vessels, despite using EUS. The results suggest that patients with crossing vessels should be treated by laparoscopic pyeloplasty. More data are needed to compare endopyelotomy with laparoscopic pyeloplasty in patients with no crossing vessels.

Ureteral stent symptom questionnaire: development and validation of a multidimensional quality of life measure.

PURPOSE: We developed the ureteral stent symptom questionnaire (USSQ), a psychometrically valid measure to evaluate symptoms and impact on quality of life of ureteral stents. MATERIALS AND METHODS: A total of 309 patients were asked to participate during different phases of our study. In phase 1 a structured literature search, 9 patient interviews and studies of 90 patients using existing instruments formed the foundation for the initial draft of our new questionnaire. In phase 2 the USSQ was pilot tested, reviewed by experts and field tested in 40 patients to produce a final 38-item draft. In phase 3 formal validation studies were performed in 55 patients to assess validity, reliability and sensitivity to change. Discriminant validation was performed by administering the questionnaire to 3 groups of patients without stents. RESULTS: The final draft addressed various domains of health (6 sections and 38 items) affected by stents covering urinary symptoms, pain, general health, work performance, sexual matters and additional problems. The validation studies showed the questionnaire to be internally consistent (Cronbach's alpha > 0.7) with good test-retest reliability (Pearson's coefficient > 0.84). The questionnaire demonstrated good construct validity and sensitivity to change shown by significant changes in the score with and after removal of stents. The new USSQ discriminated patients with stents from healthy controls (p < 0.001) and patients with urinary calculi without stents and lower urinary tract symptoms. CONCLUSIONS: Indwelling ureteral stents have a significant impact on health related quality of life. The new USSQ is a valid and reliable instrument that is expected to become a standard outcome measure to evaluate the impact and compare different types of stents.

Indwelling ureteral stents: evaluation of symptoms, quality of life and utility.

PURPOSE: We report the prevalence of symptoms associated with ureteral stents, their impact on health related quality of life and utility analysis based on the validation studies of the new ureteral stent symptom questionnaire (USSQ). MATERIALS AND METHODS: A total of 85 consecutive adult patients with unilateral indwelling ureteral stents who were asked to participate during the validation phases of the USSQ were considered for this analysis. They were asked to complete the USSQ and the EuroQol, a weighted utility instrument, 4 weeks after stent insertion and removal. In addition, 40 patients were asked to complete these questionnaires 1 week after stent insertion to assess the prevalence of symptoms and utility values at different times. RESULTS: Of the 85 patients 62 (73%) with a mean age of 50 years completed the necessary questionnaires. Urinary symptoms and pain that affected work performance and general health were important stent related problems. Of the patients 78% reported bothersome urinary symptoms that included storage symptoms, incontinence and hematuria. More than 80% of patients experienced stent related pain affecting daily activities, 32% reported sexual dysfunction, and 58% reported reduced work capacity and negative economic impact. The mean EuroQol utility values, which indicate patient satisfaction with treatment, were significantly reduced following stent insertion. CONCLUSION: Urinary symptoms and pain associated with indwelling ureteral stents interfere with daily activities and result in reduced quality of life in up to 80% of patients. Stents are associated with negative functional capacity and reduced utility values. The results have implications in terms of routine clinical practice, patient counseling and future stent research.

Flexible ureteroscopes: a user's guide.

OBJECTIVE: To compare, quantitatively and qualitatively, four small-diameter flexible ureteroscopes. MATERIALS AND METHODS: Four flexible ureteroscopes from different manufacturers, i.e. the DUR-8 (ACMI, Southborough, MA, USA), Olympus UPF-3 (Keymed, Southend-on-Sea, UK), Storz 11274AA (Karl Storz GmbH, Tuttlingen, Germany) and the Wolf 9 F (Henke Sass Wolf GmbH, Tuttlingen, Germany), were assessed quantitatively by measuring the active tip deflection and irrigation flow rate with laser fibres (200 micro m, 365 micro m), an electrohydraulic lithotripter (1.9 F) and grasping forceps (3 F) in position. They were then assessed subjectively by two endourologists who scored them, using a visual analogue scale (maximum 10), for insertion, deflection mechanism, manoeuvrability, rigidity, image quality and overall satisfaction. RESULTS: All the endoscopes are < 9 F at the tip, although the length of the smallest diameter (bevelled tip vs section of shaft) was variable. Tip deflection was 87-100% of the manufacturers' specifications and decreased by similar percentages with instruments in the working channel. The irrigation flow rate was comparable for instruments with a 3.6 F working channel (72-88 mL/min with an empty working channel), although much greater for the Wolf, which has a 4 F channel (116 mL/min). Direction and image size were nearly identical, as was the field of view, apart from the Wolf (60 degrees vs 90 degrees ). There was agreement in the user assessment for three instruments, with overall satisfaction scores being Storz (4), ACMI (7.5) and Olympus (8.6), but disagreement in scores for Wolf (1.9 vs 5.3). CONCLUSIONS: Whilst there were considerable similarities in the objective assessment among the instruments, the user assessment showed qualitative variability. Thus it is important to try the different instruments before selecting one. Additional variables to consider include durability, cost and service/warranty, which vary considerably among instruments.

Hand-assisted laparoscopic nephrectomy: complications related to the hand-port site.

OBJECTIVE: To evaluate the early results of hand-assisted radical nephrectomy and nephroureterectomy in our institution. PATIENTS AND METHODS: The records of 13 patients with malignant disease of the kidney who underwent hand-assisted laparoscopic radical nephrectomy and nephroureterectomy were reviewed retrospectively. Clinical outcomes were compared with a series of 16 patients who underwent similar procedures via a standard laparoscopic approach. RESULTS: There were three major hand-port wound complications in those who underwent hand-assisted procedures, while one other patient required conversion because of technical failure of the device. The operative duration, length of hospital stay, estimated blood loss, transfusion rate, analgesic requirement, conversion rates, and minor complications were similar between the hand-assisted and standard laparoscopy groups. CONCLUSION: There was little difference between hand-assisted and standard laparoscopy in operative duration or recovery, but there were problems with wound complications which may be related to the hand-assisted approach. We have consequently abandoned the technique in favour of a standard laparoscopic approach.

Re-auditing a regional lithotripsy service.

OBJECTIVE: To assess, in a repeat audit of a regional lithotripsy service, whether changes implemented after a regional audit in 1994 (which showed disappointing results from shock wave lithotripsy, attributable to both poor patient selection and an inadequate fixed-site lithotripter) have had any effect. PATIENTS AND METHODS: A data-collection sheet was devised to gather information on the site, size and number of stones treated, together with information on the lithotripsy treatment and outcome. Patients selected for the audit were the first 50 new patients treated with lithotripsy at each centre in 1999. As only one hospital has a fixed-site lithotripsy machine, the results of mobile lithotripsy were grouped by machine for analysis. RESULTS: There was an overall improvement in patient selection from the previous audits. Few stones of > 16 mm or < 4 mm were treated. Two units treated more ureteric stones, thought to reflect first the influence of a fixed-site lithotripter, and second a willingness to insert a ureteric stent and await the next mobile lithotripter visit. The stone free rates were all disappointingly low (16.7-26.7%) but the results improved when fragments of < 4 mm were included as "successful" giving an "overall success rate" of 45.9-66.7%. The unit with a fixed-site lithotripter appeared to perform better (two-thirds successful) than the mobile machines (Modulith SLX, 51%; Modulith SLK, 46%). One centre visited by both mobile machines had a success rate of 65% but a high rate of auxiliary procedures (35% vs 16-19% vs the fixed-site). CONCLUSION: Although these results show some improvement in patient selection for our regional lithotripsy service, stone-free and success rates are poorer than those reported elsewhere. This may reflect the modern lithotripsy machines that allow day-case treatment with minimal analgesia, and confirms reports by other authors who encourage a re-examination of success rates of shock wave lithotripsy.