Introduction and Methods

PCNL indications and techniques are evolving. BAUS developed an online data registry in January 2010 that now includes >9500 procedures. We evaluate outcomes and practices in PCNL and compare with previous analyses of the registry at 1K and 5K procedures to highlight significant changes in PCNL practice in the UK.

Results

9536 procedures were analysed and compared with previous analyses of 1028 cases (2011-1K) and 5191 cases (2015-5k). Submission of cases has stabilised at ~2,200 cases per year. Most PCNL is still prone, but supine continues to significantly increase from 5K analysis (22.4%vs.16.2,p=0.0001). Access by interventional radiologist showed a small but significant decrease from 5K analysis (63.3%vs.66.3%,p=0.0004), but not significantly different from 1K analysis. No significant changes in tract dilatation methods are seen, with balloon dilatation most popular (64.3%). Consultants increasingly perform PCNL themselves rather than their trainees (96.5%vs.84.4%(5K) vs. 79.0%(1k), p=0.0001). Laser fragmentation usage has significantly increased (9.4%vs.7.0%(5K) vs.5.8%(1k), p=0.0001), with similar usage of ultrasound/ lithoclast/lift out. Sub-analysis of 4490 cases showed 25.8% of cases used multiple stone fragmentation modalities. Nephrostomy tube usage postoperatively is significantly reduced (72.6%vs.75.6% (5k), p=0.0001). Intraoperatively 78.5% of patients were recorded as stone free, which was confirmed in 69.1% on postoperative imaging, similar to previous analyses. Complication rates are shown in Table 1.


Conclusions

PCNL practices continue to evolve in the UK. Continued contribution of data and subsequent careful analysis of the registry allows us a better understanding of PCNL in the UK.

Introduction and Objective

There is heterogeneous methodology for recording stone-free rate (SFR) within a national registry. Intra-operatively, can “further planned stone treatment” be used as a surrogate marker of SFR and treatment success?

Methods

9084 cases from the BAUS PCNL registry record SFR intraoperatively and were analysed for SFR records post-op day-1 and at 3-months follow-up (FU). SFR records were compared with intention for “further planned stone treatment”. Subgroup analysis was performed for variation with stone size and stone complexity measured by Guys stone score (GSS).

Results

Of the 9084 cases recording intraoperative SFR, 78.4% had records for SFR on post-op day-1, 37.3% at 3-months FU and 60.6% recorded intention for “further planned stone treatment” intraoperatively. X-ray KUB was most frequent imaging modality used (67.9%), then CT and USS (16.1% and 6.1% respectively). Using intention for “further planned stone treatment” as a marker of success compared to complete clearance on fluoroscopy intraoperatively had a sensitivity of 92.7% (95% CI 91.81-93.53) and specificity of 72.6% (95% CI 70.48-74.67). When compared to clearance on post-op day 1 imaging the sensitivity was 97.6% (95% CI 96.91- 98.23) and specificity 63.08% (95% CI 61.02-65.10). Subgroup analysis of stone diameter and GSS revealed no statistically significant differences.

Conclusions

Using intention for “further planned stone treatment”, does show correlation with reported SFR intraoperatively and post-op day 1. Accurate recording of SFR to measure treatment success within a national registry requires enhanced submission of FU data and a consistent approach to the timing and imaging modality used.

Introduction
Supine percutaneous nephrolithotomy (sPCNL) offers advantages, in terms of ease of positioning, operative time and anaesthetic safety, without compromising stone clearance. We report our experience of sPCNL over 10 years.
Patients and Methods
All sPCNL performed at our hospital from February 2007-June 2017 were recorded prospectively. Demographics, stone information (size, number, position and Guy’s Stone Score), and comorbidity were entered, followed by operative detail, stone clearance following CTKUB (<3months) and complications (Clavien-Dindo).
Results
420 sPCNL procedures were recorded from2007-2017, including 261(62%) male and 159(38%) female patients, of median age 54(18-90) and median BMI 28(18-70).
Median operative time was 70minutes(25-240). 72staghorns were treated (58complete, 14partial). Median stone diameter was 16mm(6-54). Puncture sites were lower pole in 248(59%), interpolar in 100(24%), upper pole in 54(13%), and multiple in 17(4%) procedures.
89(21%) procedures incorporated simultaneous ureteroscopy for ureteric stones or renal stone manipulation.
282(67%) were totally stone-free. A further 79(19%) had residual fragments <2mm. 12(3%) cases had failed access.
28 Clavien Grade II, 11 Grade IIIa, 11 Grade IIIb and 2 Grade IVa were recorded. These included 5(1%) pseudoaneuryms requiring embolisation, 25(6%). UTI/sepsis, 8(2%) transfusion. One pneumothorax was recorded, requiring emergency chest drain. One bowel injury was recorded, requiring primary repair. Median length of stay was 3(1-16) days.
Conclusions
Supine PCNL can be adopted as the standard approach in all patients and all stones. From this large series of sPCNL, we demonstrate favourable stone free rates, with serious but rare complications.

Introduction

Stone diesease in the paediatric population in the UK is rare and managed in a few centres. We run a service with a paediatric surgeon and an adult stone surgeon, offering all modalities of treatment from a joint clinic. We have reviewed 9 years of percutaneous surgery in this paediatric population.

Objectives

To evaluate the outcomes of PCNL in the management of renal stones in children in our centre over a 9 year period.

Methods

All patients under 16 years old who underwent a PCNL at our institution between 2008 and 2017 were retrospectively reviewed. We collected demographic information, comorbidities and surgical details; stone complexity and follow up information to identify complications were also recorded.

Results

PCNL was performed by one surgeon, performing 30 procedures in 28 patients. The mean age was 7.3 years (Range 11months to 16 years). The mean stone diameter was 19.2mm. The Guy’s Stone Score (GSS) was as follows. GSS 1 = 3; GSS 2 = 9; GSS 3 = 3; GSS 4 = 13) The minor complication rate (Clavien Dindo 1-2) was 10.3%, and major complication (Clavien Dindo 3-4) rate was occurred in 10.3. No patients required a blood transfusion.

Conclusions

PCNL is a safe procedure even in the extremely young. We believe the combined clinic with a paediatric urologist and adult stone surgeon allows modern approaches to stone disease to be offered to the very young.

Introduction
Constantly increasing patient numbers created severe pressure on outpatient clinics. New patient care pathways are needed that can reduce those pressures and improve patient overall care. We set up a weekly virtual stone clinic whose aim was to ensure that all stone patients were reviewed by the stone team and triaged to the appropriate stream. All stone referrals were captured by the Stone Coordinator and reviewed in the VSC by the Stone Consultant(s), SpR, Stone Nurse and Research Nurse.
Aim and Methods
We aimed to assess the effectiveness of our virtual stone clinic in saving outpatient appointments, diverting consultant clinic appointments to nurse led consultations (in person or via telephone) and expediting patient care pathways to meet treatment target pressures. Data were collected prospectively for 5 months from 12/12/16 to 17/5/17
Results
The VSC reviewed 300 clinic appointment requests. Of those 65 appointments were avoided completely, 45 were changed to telephone appointments and 127 to specialist nurse appointments. In addition 178 patients were referred for opinion. In 24 the management decision was altered avoiding last minute cancellations after re-discussion with the patients. Clinic appointments were expedited in 17 cases for clinical reasons and 6 patients were admitted for urgent intervention.
Conclusion
We found that utilizing a 90 minute VSC every week has significantly reduced outpatient clinic pressures, expedited patient care in appropriate cases and prevented last minute changes to procedures or cancellations. Overall it improved patient management while saving significant resources in terms of time and money.

Introduction
Virtual clinics have been used in several specialities in order to decrease face to face clinic appointments (FTF), saving patient and clinician time. We sought to assess recurrent stone clinic attenders’ quality of life and satisfaction with being followed up in a novel virtual stone clinic as well as financial implications

Methods
A Symptom questionnaire and two validated quality of life questionnaires (EQ -5D, general QOL) and (WIS-QOL, stone specific QOL) were posted to all patients due annual stone follow up. They were given a 2-week window to attend for XRKUB. Subsequently they received a letter from the consultant urologist following review of symptom scores and imaging.

Results

The initial forty six patients were included in this pilot. 85% of patients found the flexibility of XRKUB timing as very or extremely helpful and 59% were able to avoid time off work. 96% of patients would be happy to have ongoing follow up using this clinic format. Costing analysis showed a decrease in direct costs per patient to £7.92 versus £24.74 in the FTF clinic. WISQOL scores varied significantly between symptomatic and non symptomatic patients (79.2 vs 87.6, p 0.03, ttest) whilst the EQ5D failed to differentiate between groups (0.80 vs 83.8, p=0.13 ttest).

Conclusions
The virtual clinic provides time and financial benefits and is widely acceptable to patients. In this cohort the WISQOL, a relatively new stone specific QOL questionnaire is able to detect patient perspectives in symptomatic versus non symptomatic patients where the generic EQ5D tool cannot.

Objective
We followed a cohort of patients who presented in June 2015 to provide a “snapshot” of UK practice for the management of patients with acute loin pain.
Methods
827 patients had an emergency CTKUB across ten UK hospitals in June 2015, of whom 408 (49.3%) had urolithiasis confirmed. Their records were analysed at 6 weeks, 6 months and one year to provide insight into their status over the year following their acute presentation.
Results
62.9% of the patients with urolithiasis had ureteric colic (42.6% in the distal ureter and 16.7% in the proximal ureter). 25.9% (n=106) had renal stones only. 84% were managed conservatively: 56.8% were not admitted, and of those that were, 57.7% did not require active intervention. The use of MET was already in decline with just 31% prescribed it. Patients who required acute intervention had larger stones than those not admitted (median 7.7mm; mean 9.5mm vs median 4mm; mean 4.5mm). Stone size also predicted the likelihood of early re-presentation ranging from 4.1% for stones 1-4mm to 15.3% for stones 7-10mm during the first six weeks post presentation.
Discussion / Conclusion
This study has shown that patients with larger stones were more likely to be admitted, require intervention (especially emergency drainage), re-present to emergency services and take longer to be stone and tube free than patients with smaller stones. The definitive management of patients with larger stones (i.e. >7mm) should be therefore be planned as soon as feasible to reduce patient uncertainty and tube-related morbidity.

Introduction
Cranberry supplements are commonly used as a natural deterrent to urinary tract infection. However, one small study (Terris et al. Urology 2001) found an increase in urinary oxalate levels following cranberry supplementation. This has led to its use with caution in patients susceptible to nephrolithiasis. Furthermore, most commonly available cranberry tablet preparations contain Vitamin C, which has been independently shown to increase urinary oxalate excretion.

The aim of this study is to investigate the influence of cranberry supplementation on urinary oxalate levels.

Methods
Fourteen healthy volunteers (8 male, 6 female), were randomised to receive cranberry tablets alone or cranberry tablets containing Vitamin C. Tablets were taken at the manufacturers recommended dosage for a period of 14 days. Participants provided a 24hr urine collection at trial entry and day 14. Urinary variables were compared to assess for changes in oxalate levels.

Results
The mean age was 27 years (21-43). There was no difference in the 24hr urine volume pre or post commencement of cranberry tablets (2.17L ±1.24 vs 2.57L ±1.43). An increase in urinary oxalate levels compared to baseline values was observed both in those taking cranberry only tablets (mean increase: 143.2±160.3µmol/24hours) and those taking cranberry tablets containing Vitamin C (mean increase: 226.78±242.6µmol/24 hours). The type of cranberry preparation did not significantly impact the degree of oxalate excretion observed (p=0.45).

Conclusion
Cranberry tablets increase urinary oxalate excretion. Patients should be counselled regarding the potential nephrolithic effects of taking these supplements, particularly those with a propensity towards kidney stone formation.

ntroduction
Diagnostic pressure on endoscopy suites can result in stent removal not receiving the required priority andunnecessary morbidity for patients. As well as using stents with extraction strings, the introduction of a portable single-use flexible cystoscope for ureteric stent removal (IsirisTM), offered an opportunity to negotiate these issues by relocating stent removal to the office/clinic. This study aimed to determine whether such flexibility reduced stent dwell time with the assumption this would improve patient experience and decrease associated complications.

Methods
A retrospective review of ureteric stents placed during stone procedures was undertaken. Data collection included; patient demographics; stent dwell times; the number of emergency department (ED) attendances and hospital readmissions; procedure cancellation rates and the number of urinary tract infections

Results
In total, 162 stents were removed (113 Standard, 34 IsirisTM, 15 via strings). Excess dwell time was reduced in both IsirisTM (median 1 day, mean 1.37 days, p=0.0009) and Strings Groups (median 0.96 days, mean 0.96 days, p=0.022) compared with the Standard Group (median 8 days, mean 15.34 days). ED attendances and readmissions were reduced by 33.5% and 22% respectively in the IsirisTM Group compared with the Standard Group. There were no ED attendances in the Strings Group. Reductions in length of stay, urine infections and cancellation on the day of procedures were also observed.

Conclusion
The clinical flexibility provided by IsirisTM and ‘stents on strings’ has objectively improved patient experience and is associated with a reduction in complications as well as increasing diagnostic capacity and cost efficacy.

Aims:
To describe our first 12 month experience of using covered ureteric stents for managing ureteric strictures and leak.
Methods:
Covered, self-expanding, large calibre ureteric stents (Allium™ and Uventa™) were introduced in September 2015 and scrutinised with prospective audit to assess efficacy and outcome. Insertion was performed after balloon dilatation, if necessary. Follow up included routine biochemistry, radiological imaging and clinical review. Median follow-up is 7 Months.
Results:
21 patients had 26 stents inserted. 24 Stents were placed retrogradely while 2 were placed antegradely, all with interventional radiology. 14 ureters had benign disease and 12 malignancy. 8 patients had postoperative ureteric injuries. All 5 ureteric leaks were successfully treated without the need for nephrostomy. 20 Renal units had previous JJ stents that failed of which18 were salvaged.
Two patients obstructed with covered stents in-situ due to ureteric reaction just distal to the stent. The stent itself remained patent in all cases. 2 stents migrated requiring re-intervention.Ten cases were performed as emergencies and median length of stay for elective cases was 1 day. The complication rate was minimal with one 30 day clavien II (sepsis).
Conclusion:
To the best of our knowledge very few UK centres utilise these novel covered metal stents. They provide good renal tract drainage and are a useful addition to the armamentarium for the endo-urological management of complex ureteric pathologies. Reduced nephrostomy and stent symptoms/changes improve quality of life. Long-term follow-up data and cost-benefit analysis is clearly required.