










































This is an open access article under the terms of a license that permits non-commercial use, provided the original work is properly cited.  
© 2021 The Authors. Société Internationale d'Urologie Journal, published by the Société Internationale d'Urologie, Canada.

A Global Perspective of Stenting After Ureteroscopy:  
An Observational Multicenter Cohort Study
Ranan Dasgupta,1 Teng Aik Ong,2 Jasmine Lim,2 Retnagowri Rajandram,2 Xiaofeng Gao,3 
Lukman Hakim,4 Patrick Mburugu,5 Rohit Ajmera,6 Emrah Yuruk,7 Yeong-Shiau Pu,8 
Petrisor Geavlete,9 Raed A. Azhar,10 Shingai Mutambirwa,11 Joyce Baard 12

1 Imperial Urology, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, United Kingdom 2 Department of Surgery, Faculty of Medicine, University of 
Malaya, Kuala Lumpur, Malaysia 3 Department of Urology, Changhai Hospital, Second Military Medical University, Shanghai, China 4 Department of Urology, Airlangga 
University, Dr Soetomo Hospital, Surabaya, Indonesia 5 Department of Urology, Kenyatta National Hospital, Nairobi, Kenya 6 Jawahar Lal Nehru (JLN) Medical College, 
Rajasthan, India 7 Department of Urology, Bağcılar Training and Research Hospital, 

.
Istanbul, Turkey 8 Department of Urology, College of Medicine, National Taiwan 

University, Taipei, Taiwan 9 Department of Urology, Saint John Emergency Clinical Hospital, Bucharest, Romania 10 Department of Urology, King Abdulaziz University, 
Jeddah, Saudi Arabia 11 Department of Nuclear Medicine, Sefako Makgatho University, Pretoria, South Africa 12 Department of Urology, Amsterdam UMC, University of 
Amsterdam, the Netherlands

Abstract

Objectives With an increasing number of patients undergoing ureteroscopic surgery worldwide for stone disease, 
and the concomitant pressures on health care resources, we aimed to review global patterns for ureteric stenting 
following ureteroscopy. With a centralized electronic database, a longitudinal cohort study was designed to help define 
the indications for stenting, type of drainage, and methods of stent removal.

Methods This multicenter study was conducted prospectively, with centralized data acquisition by uCARE (research 
arm of the Société Internationale d'Urologie), and registered at ClinicalTrials.gov (NCT03567421). Along with baseline 
demographic data, details were entered for stone imaging characteristics, intraoperative information, including urine 
culture, and exit strategy for stent removal. An independent audit was undertaken to sample the accuracy of data 
entered across the sites.

Results In total, 2544 patients were included from 50 centers in 15 countries. There  were 1969 patients with ureteric 
stones, and 942 with renal stones. While 41% ureteric stones were distal (median length 10mm), 52% renal stones 
were in the lower pole (median diameter 11 mm). The majority of patients (68.8%) were given antibiotics at induction; 
20.6% were “pre-stented” before the ureteroscopy, and a high percentage were stented following ureteroscopy (91%). 
The majority of the stents (85.1%) were polyurethane, mean duration of stent after surgery was 27 days, and 80% of 
stent removals were undertaken in the operating room.

Conclusion This is one of the largest prospective global cohort studies, reflecting widespread usage of stenting, 
despite emerging evidence to the contrary. Stent removals may also be modified with time, as the pressure on health 
care resources mounts.

Introduction

Globally, the past decade has witnessed the increasing trend towards ureterorenoscopic treatment of stone 
disease[1–3]. These procedures may involve use of semi-rigid or flexible instruments, and either digital or fiber optic 
technology. The miniaturization of the scopes, along with the availability of tools (laser fibers, guidewires, baskets), 
has led to ureterorenoscopy (URS) overtaking extracorporeal shockwave lithotripsy (ESWL) in terms of numbers of 

Key Words Competing Interests Article Information

Ureteral stent, urolithiasis, ureteroscopy, stent None declared. Received on October 2, 2020 
Accepted on December 1, 2020

Soc Int Urol J. 2021;2(2):96–105

DOI: https://10.48083/HRLS8587

96 SIUJ  •  Volume 2, Number 2  •  March 2021 SIUJ.ORG

ORIGINAL RESEARCH

mailto:joyce.baard%40siu-urology.org?subject=SIUJ
ClinicalTrials.gov
https://10.48083/HRLS8587
http://www.siuj.org


procedures for upper tract stone disease[4]. It is accepted 
that patients will sometimes need a ureteric stent at 
the end of a URS procedure, although debate remains 
about the indications for this[5]. The use of a stent has 
associated morbidity and is often the aspect of a URS 
procedure that a patient remembers most vividly.

W hi le dif ferent g uidelines and rev iews have 
attempted to offer broad outlines on the appropriate use 
of stents, there remains much variation in practice with 
respect to their usage. Data from 11 885 URS procedures 
in the Clinical Research Office of the Endourological 
Society (CROES) study gave an insight into the 
frequency of use of stents (84.1% for all procedures, 60% 
after ureteric stone treatment, 80% after renal stone 
treatment), highlighting the need for further detail on 
the indications and features of these stent insertions[6].

The importance of this common aspect of stone 
treatment, with implications for health care costs and 
delivery worldwide, led to the current longitudinal 
cohort study with centra lized independent data 
acquisition, allowing us to analyze the practice patterns 
across the globe and address the key questions of 
indication for stent insertion, the type and duration of 
drainage, and patterns for stent removal techniques.

Methods
This is a prospective multicenter observational longi-
tudinal cohort study of patients with ureteric or renal 
stones treated by ureterorenoscopy. The study was 
executed by uCARE, the Office of Research of the 
Société Internationale d’Urologie (SIU).

To meet the inclusion criteria, patients had to be ≥18 
years old, able to give written consent, and suitable for 
treatment of a ureteric or renal stone by ureteroscopy. 
The estimated enrollment for this registry was at least 
30 patients from 50 participating centers worldwide. 
All participating centers obtained ethical approval or 
a waiver from their local Institutional Review Board 
(IRB).

Patient data were anonymized, stored in a centralized 
database, and audited at the conclusion of the study 
period. This study was registered at ClinicalTrials.gov 
(NCT03567421) on June 25, 2018.

Study assessments: Data entry was undertaken at 3 
timepoints: T1 (baseline, on the day of the URS), T2a 
(day of stent removal for stented patients) or T2b (first 
outpatient clinic, for unstented patients). The study 
scheme is outlined in Figure 1. The data collected were

Baseline characteristics: age, gender, American Society 
of Anesthesiologists physical status classification system 
(ASA I-IV), body mass index, urinary tract infection 
(UTI), prior stent use, previous stone treatment, and 
other morbidity.

Stone characteristics: location, number of stones, 
largest dimension (stone burden, surface area = length × 
width × 0.25 × 3.14159).

Abbreviations 
ASA American Society of Anesthesiologists

ESWL Extracorporeal shockwave lithotripsy

IQR Interquartile range

PCNL Percutaneous nephrolithotomy

SIU Société Internationale d’Urologie

UAS Ureteral access sheath

URS Ureteroscopy ureterorenoscopy

UTI Urinary tract infection

Patient Selection

1. Aged ≥ 18 years old with a ureter or renal stone
2. Plan for ureteroscopic (URS) treatment

Day of Surgery (T1)

Postoperative Visit (T2)

Stented
Patients

Non-Stented 
Patients

Day of Stent 
Removal (T2a)

Day of First Outpatient 
Clinic (T2b)

Post-URS

Data collected: baseline characteristics, stone characteristics, 
intraoperative data and exit strategy (stending status)

Data collected: 
stent removal setting and 
postoperative details

Data collected: 
postoperative details

FIGURE 1. 
Study scheme

97SIUJ.ORG SIUJ  •  Volume 2, Number 2  •  March 2021

A Global Perspective of Stenting After Ureteroscopy: An Observational Multicenter Cohort Study

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Intraoperative information: use of antibiotics, use 
of anesthesia, whether pre-stented (and indication for 
pre-stenting), need for ureteric dilatation, whether 
semi-rigid and/or flexible ureteroscopy, use of ureteral 
access sheath (UAS), type of lithotripsy energy, duration 
of surgery (defined as from passage of transurethral 
instruments to insertion of stent or ureteric drainage 
catheter), stone-free status assessed endoscopically.

Exit strategy: ureteric drainage (stent or ureter catheter), 
type of stent, indication, and indwelling time.

Stent removal: actual indwelling time, type of anes-
thesia for stent removal. 

Data are presented as descriptive information, 
reporting mean (with standard deviation) or median 
(i nterqua r t i le ra nge) for nor ma l ly d ist r ibuted 
and skewed (continuous) variables, respectively. 
Dichotomous or categorial numbers are reported as 
absolute numbers or as percentages.

Results
The study was launched on June 1, 2018, and data 
collected until end of August 2019. A total of 2544 
patients were included from 50 centers from 15 
countries (Figure 2 and Appendix 1 for an overview of 
participating centers).

APPENDIX 1. 
Participating research centres

FIGURE 2. 
Inclusion per country

0

8

41

42

48

65

91

102

179

186

202

224

493

855

United States

Iraq

Greece

Saudi Arabia

Kenya

Iran

Romania

India

Indonesia

Taiwan

Malaysia

China

Turkey

200 400 600 800700500300100 900

3

5

South Korea

South Africa

Baseline Characteristics
Of a total of 2544 patients, 2540 with complete case 
records were included. Baseline characteristics at 
inclusion are described in Table 1.

Our cohort had a mean age of 49.0 years (range 18 to 
93 years), 64.3% were male, and the majority had an 
ASA classification 1 (51.5%) or ASA 2 (40.4%). Diabetes 
mellitus (13.9%) and previous urinary tract infection 
(16%) were frequently reported comorbidities.

Of the 671 patients (26.4% of total) who had under-
gone previous stone surgery, 362 (53.9%) had experience 
of previous ureteroscopy, 272 (40.5%) previous ESWL, 
and 114 (17.0%) PCNL. Renal anomalies were infrequent 
(3.6%), and only 36 patients had a solitary functioning 
kidney.

Stone Characteristics
In total, 1969 stones were reported in the ureter and 942 
stones in the renal system. The distribution of ureteric 
and renal stone location is shown in Figure 3. Ureteric 
stones were most often located in the distal ureter 
(40.8%), and just over half of the renal stones (52.1%) 
were in the lower pole. The median stone burden for 
ureteral stones was 47.1 mm3 (IQR 27.5 to 75.4) with a 
median length of 11.0 mm (IQR 7.0 to 12.0) and median 
width 6 mm (IQR 5.0 to 8.0). The renal stones in this 
cohort were larger with a median stone burden of 66.0 
mm3 (IQR 28.4 to 117.8) with a median length of 10.0 
mm (IQR 7.1 to 15.0) and median width 8.0 mm (IQR 
5.0 to 10.0).

Intraoperative Details
Of those patients given antibiotics, the majority (68.8%) 
were administered a prophylactic dose, whereas 30.8% 
had a therapeutic course after the procedure.

Just over 20.6% (n = 524) had a stent inserted before 
the definitive ureteroscopy procedure.

Reasons for these stent insertions included tight 
ureter (16.2%) and ureteric narrowing/stenosis (17.2%). 
Interestingly, the main indication for pre-stenting was 
the surgeons’ preference (23.3%). The median indwelling 
time in these patients was 30 days (IQR 20 to 60 days).

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In 81.7% of procedures, a semi-rigid ureteroscope was 
used; the dimensions of semi-rigid ureteroscopes used 
ranged from 4.5Fr to 13Fr, with the commonest being 
6 to 8 Fr as expected. In 30.8% a flexible ureteroscope 
was used, mainly fiber optic (66.2%). The variety of 
instruments together with the other intraoperative 
details are shown in Table 2 and Figure 4.

In 27.9% of procedures a UAS was used. In almost 
half of these cases, the preferred UAS was sized 12 
or 14 Fr (47.7%). In the majority of cases (76%), laser 
stone fragmentation was used, and in 24%, pneumatic 
lithotripsy was used.

Stent Details
In the vast majority (n = 2332; 91.3%) of the 2429 patients 
undergoing insertion of a ureteric drainage tube, a 
double J stent was used, rather than a ureteric stent. The 
reasons for stent insertion were concern about ureteric 
edema (54.9%), lengthy procedure (4.9%), difficult access 
(5.3%), residual stones (23.6%), use of a UAS (15.8%), 
ureteric stricture (12.6%) or lesion (12.0%), solitary 
kidney (1.0%), or surgical preference (29.8%).

The majority were polyurethane (85.1%%) versus 
silicone (6.1%) or other (5.1%) materials.

Whereas 759 patients (31.2%) had a multi-length stent, 
the remaining 1668 had a specific size; the commonest 
being 24cm (18%), 26cm (43.5%) or 28cm (32.5%). The 
most commonly used double J stent diameters were 6 Fr 
(54.5%) and 4.7 Fr  (34.9%).

In terms of stent removal, with median duration 
being 27 days (IQR 15.0 to 37.0), the majority were 
undertaken in the operating room (80.0%), with very few 
favoring self-removal by string (1.9%) and a few opting 
for removal in the office setting (19.9%). The operating 
room removals were mostly by rigid cystoscopy (61.6%), 
followed by ureteroscopy (25.1%) and flexible cystoscopy 
(13.3%)

Discussion
The morbidity associated with ureteric stenting is the 
aspect of stone treatment that patients tend to remember 
most vividly. Yet there remains a well-documented wide 
variation in practice. A recent systematic Cochrane 
review found it difficult to make firm conclusions about 
the practice because of what the authors described 
as moderate to low “certainty of evidence.” Indeed, 
the review confirmed that there is no agreed-upon 
definition of an “uncomplicated” ureteroscopy. This 
being a global issue, we aimed to analyze this practice 
in an inter-continenta l study, w it h prospective 
data acquisition, and identify stenting patterns and 
preferences across the world[5]. This study allows some 
key conclusions, namely the types of stenting, duration 
of stent, antibiotic usage, and differences in management 

TABLE 1. 

Demographics

Variable n (%)

Patients included 2544

Gender

Male 1635 (64.3)

Female 904 (35.5)

NA 5 (0.2)

Age mean (range) 49.0 (18.0–93.0)

BMI median (IQR) 25.5 (23.3-28.4)

ASA

I 1310 (51.5)

II 1026 (40.3)

III 188 (7.4)

IV 11 (0.4)

V 1 (0.0)

NA 8 (0.3)

Medical history

OAB 31 (1.2)

UTI 406 (16.0)

DM 353 (13.9)

Chronic prednisolone use 27 (1.1)

UPJ stenosis 42 (1.7)

Longstanding immobilization 17 (0.7)

Previous surgery

UPJ-plasty 19 (0.7)

Stone treatment 671 (26.4)

ESWL 272 (40.5)

URS 362 (53.9)

PCNL 114 (17.0)

Other 49 (7.3)

Ureter dilatation 131 (5.1)

Other urological surgery 113 (4.4)

Renal anomaly 91 (3.6)

Ectopic kidney 4 (4.4)

Horseshoe kidney 10 (11.0)

Solitary kidney 36 (39.6)

Other 41 (45.1)

ASA: American Society of Anesthesiologists;  
BMI: body mass index; DM: diabetes mellitus;  
ESWL: extracorporeal shockwave lithotripsy;   
NA: not available/specified; OAB: overactive bladder;  
OAC: oral anticoagulation; PCNL: percutaneous nephrolithotomy;  
UPJ: ureteropelvic junction; UTI: urinary tract infection;  
URS: ureteroscopy. 

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for proximal stones. These findings are of relevance both 
for urologists and for those responsible for delivery of 
health care systems, and for the design of elective and 
emergency pathways.

With the benefit of a central online database, records 
were uploaded prospectively by the host centers in 
real time, and data entries could thus be audited both 
during and at the conclusion of the study period. Over 
2500 records were thus collated, of which 10% were 
sampled for verification and validation of data entry. 
The global distribution is shown in Figure 2 and 
Appendix 1, highlighting the geographical spread of 
the centers contributing information to this study, with 
representation from Asia, the Middle East, Europe, and 

Africa. This covers a range of health care systems, thus 
reducing any bias related to financial remuneration, for 
instance.

The high rate of ureteric stenting after ureteroscopy 
in this global cohort study (2331/2540; 91.8%) is in line 
with previous reports, with the commonest justification 
being concern about ureteric edema leading to pain and/
or obstruction[6]. Although various guidelines have 
proposed that uncomplicated ureteroscopy can avoid 
routine stenting post-URS, there remains uncertainty 
about the zone that lies between “complicated” and 
“uncomplicated,” and this is ref lected in the high 
stenting rates worldwide[2,3,7–10]. The consistent high 
rates, regardless of country as per our study, suggest 
that this is a universal clinical concern and is unrelated 
to health care system. Nevertheless, almost 40% of the 
cases were for distal stones, and therefore one might 
expect a slightly lower propensity for stenting in these 
cases, compared with the 35% proximal stones for which 
a stent may be somewhat expected. It is possible to 
speculate that the reason for this high rate of stenting for 
distal stones is related to the concern about the higher 
rate of hospital readmission for unstented patients 
post-URS. However, this is not captured in the dataset 
as “surgical preference,” which is listed as the reason in 
only 30.0% of cases. While there would undoubtedly be 
overlap with those reporting ureteric edema as the cause, 
one would expect “surgical preference” to be higher if 
listed.

The high proportion of stent removals that were 
undertaken in the operating room, as opposed to the 
office, was somewhat surprising, especially with the 
widespread availability of f lexible cystoscopy and 
indeed a novel cystoscope with the grasper inbuilt[11]. 
Furthermore, the number of stents-on-string was 
surprisingly low, and this may be further developed, 
particularly following the coronavirus pandemic and 
the move to reducing unnecessary hospital visits. There 
remains uncertainty about the optimal timing for such 
stent removal—24 to 48 hours, > 72 hours, etc—and 
this relates to the questions about duration of ureteric 
edema after ureteroscopy. Indeed, this is likely to be 
one of the factors that drives surgical preference for 
stenting. The pilot study by Paul et al., although it had 
a small sample size and retrospective design, suggested 
a higher proportion of postoperative issues for those 
with stent removal on day 3 versus on day 7[12]. This 
study also found that almost 50% of patients preferred 
to avoid stent-on-string removal. Again, this is an 
area that warrants review through a validated patient 
reported outcome measure. Whether a local anesthetic 
office-based stent removal, or stent-on-string removal, 
it will be interesting to review whether the effects of the 
pandemic change the current global practice patterns.

TABLE 2. 

Intraoperative details

Variable n (%)

Antibiotic regimen

Prophylactic 1749 (68.8)

Therapeutic   784 (30.8)

Pre-stented  524 (20.6)

Reason for pre-stentinga

Surgeons’ preference  122 (23.3)

Tight ureter  85 (16.2)

Ureter stenosis  90 (17.2)

Solitary kidney  17 (3.2)

Otherb  264 (50.4)

Indwelling time when pre-stented 
(days), median (IQR)

               30.0 (20.0–60.0)

Ureter dilatation performed          208 (8.2)

UAS            710 (27.9)

10/12            226 (31.8)

11/13              85 (12.0)

12/14          339 (47.7)

Other          60 (8.5)

Type lithotripter

Laser   1929 (75.8)

Pneumatic         608 (4.3)

Ballistic            25 (0.1)

Other  83 (3.3)

Duration surgery (min), median (IQR)        45.0 (30.0-60.0)

Impacted stone             924 (36.3)

Stone free             13 (0.5)

UAS: ureteral access sheath, a Multiple answers possible,  
b Including obstructing stone.

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URETER Proximal Distal Upper 
Pole

Interpolar Lower 
Pole

RENAL Renal
Pelvis

UPJMID

8,8

29,3

52,1

26

21,4

40,8

24,1

38,1

URETER Proximal Distal Upper 
Pole

Interpolar Lower 
Pole

RENAL Renal
Pelvis

UPJMID

8,8

29,3

52,1

26

21,4

40,8

24,1

38,1

One of the key questions for ureteroscopic stone 
treatment is whether primary URS is feasible or whether 
a period of pre-stenting is required. This is likely to differ 
between the treatment of ureteric stones (in which the 
majority, though not all, of even proximal stones may 
be accessible at the initial procedure) and renal stones 
(in which safe practice, even with availability of access 
sheaths, may preclude reaching a stone in the case of 
a tight ureter). Our relatively low figure of 20.6% pre-
stented patients is consistent with other reports: 11.9% 
preoperative placement for ureteric stones, 36.4% for 
renal stones[13]. This likely reflects the fact that most 
upper tracts are accessible by the miniaturization of 
the technology (with use of access sheaths and flexible 
ureterorenoscopes) but that some ureters will naturally 
remain too tight to permit safe retrograde passage 
without a period of passive dilation. This figure may 
also help with decision-making when the alternatives of 
ESWL and PCNL may be considered in terms of stone-
free rates and choice of primary procedure. With the 
increasing recognition of mini-PCNL, the boundaries 
between URS and PCNL for renal stones have shifted 
over the past decade.

A further area of variability in practice is the 
prophylactic use of antibiotics and the prescription of 
antibiotics following the procedure. It remains fairly 
standard to use antibiotics at the time of URS, with 
approximately 2/3 giving a dose at induction, though 
a relatively high proportion (almost 1/3) continued a 
course of antibiotics after the procedure. While the 
latter practice would certainly be advisable when 
there may be a risk of ongoing infection (eg, recent 

preoperative UTI, colonized stent, neuropat hic 
patients, etc), the unquestionable global problem of 
antimicrobial resistance should lead to more judicious 
use of antibiotics. This should be reflected in guidelines, 
which have generally deferred to “local practice,” with 
the lack of high-quality evidence being cited as a reason 
for the lack of a universal standard[2,3,7,8]. Of course, 
the other challenge is establishing the optimal type and 
dose of antibiotic (eg, an aminoglycoside, a penicillin, a 
cephalosporin, a quinolone, or a combination).

Urinary tract infections, hematuria, and stent-related 
symptoms are known postoperative problems associated 
with both the procedure as with stenting and may also 
be related to the duration of stenting. Whether reducing 
this stent indwell time (eg, by greater use of stent-on-
string) would impact on the postoperative UTI rate, 
further research into optimal ureteric drainage would 
ideally incorporate such infection data.

In a global study such as this, one would expect to 
observe variations in the use of UAS; with 710 cases 
(27.9%) using this, this figure is broadly as expected, 
especially for the number of proximal ureteric and renal 
stones. The proliferation of endourology expertise and 
technology would appear to have translated into use 
of this disposable. Although a higher rate would be 
expected in a renal stone rather than a ureteric stone 
study alone, the current figure illustrates familiarity with 
these sheaths globally; the relatively similar numbers for 
the 10/12 Fr size (31.8%) and 12/14 Fr (47.7%) may reflect 
local availability and experience. This may well also have 
an impact on stenting, as some who favor use of access 

FIGURE 3. 
Stone location
Ureter n = 1969   Renal n = 942

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sheath may argue for the benefits of stenting due to 
theoretical issues about edema associated with UAS.

Limitations of this study include those of any study in 
which the data entry is by the individual center, but it has 
2 advantages over other studies of practice (eg, online 
surveys, snapshot audits): (1) the centralized database 
was hosted by an independent organization, and (2) real-
time entry meant that recall bias could be minimized, 
while the completion of datasets was maximized, and 
spurious or outlying data could be followed up. Data 
quality was assessed by an appointed audit committee, 

who were able to interrogate 10% of all cases, and 
confirmation of consent, imaging, and patholog y 
reports were all accessed, and operative details were also 
verified. This process revealed that some centers kept 
original data in print form while others had moved to 
electronic data, and some used a combination.

While the questionnaire was designed in English, 
the consent process relied on translation locally, and the 
governance of informed consent relied on robust local 
Institutional Review Board approval at each center.

Finally, the listing of stent indication under “surgeon 
preference” was a broad variable without any qualitative 
description (ie, how this differed from concern about 
edema, residual fragments, etc).

Conclusion
This large multicenter cohort study reflects the current 
practice of stenting following ureteroscopy for stone 
disease and reveals widespread use of stenting despite 
an increase in suggestions that for certain cases, this 
morbid aspect of the surgery can be avoided. Where 
stents are used, the practice of stent-on-string remains 
underused, again reflecting current surgical preference. 
Future studies should address the indications for 
stenting in greater detail and help improve stent-related 
morbidity in the future

Acknowledgments
The authors would like to thank the following for their 
help.

Research Council Representatives: Rui Chen, Chinese 
Urological Association; Prodromos Philippou, Cyprus 
Urological Association; Yasser Farahat, Emirates 
Urological Society; Selcuk Guven, Eurasian Uro-
oncological Association; Bernhard Ralla, German 
Society of Residents in Urology; Athanasios Papatsoris, 
Hellenic Urological Association; Lukman Hakim, 
Indonesian Urological Association; 

Moha mmad Hadi Radfar, Iranian Urologica l 
Association; Yoshihiko Tomita, Japanese Urological 
Association; Patrick Mburugu, Kenya Association of 
Urological Surgeons; Jae Young Park, Korean Urological 
Association; Teng Aik Ong, Malaysian Urological 
Association; Paul Villanti, Movember Foundation; Raed 
A. Azhar, Saudi Urological Association; André van der 
Merwe, South African Urological Association; Yeong-
Shiau Pu, Taiwan Urological Association.

Audit Committee members (for patient data audit): 
Yigit Akin, Samuel Yee.

SIU Central Office (for study coordination and 
database management): Christine Albino, Brittany 
Scarfo.

FIGURE 4. 

Instrumentation (%)

SEMIRIGID
SCOPE

< 6 8 9 >9

1,3
3,5

22,1

27,9

6

22,1

7

23,1

FLEXIBLE
SCOPE

Digital Fiber-
optic

Single-
use

Other

21,3

66,2

10,6

2,3

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This research study would not have been possible 
without the support from the Société Internationale 
d’Urologie.

We would like to thank the study team and all 
the research investigators who participated in the 
enrollment of patients for this study. See Appendix 1 for 
a complete list of participating centers.

Author Contributions
Ranan Dasgupta: drafting of the manuscript, acquisition 
of data, reviewing of the manuscript.

Teng Aik Ong, Jasmine Lim, Xiaofeng Gao,  Lukman 
Hakim, Patrick Mburugu, Rohit Ajmera, Emrah Yuruk, 

Yeong-Shiau Pu,  Petrisor Geavlete, Raed A. Azhar, 
Shingai Mutambirwa: acquisition of data, critical 
revision of the manuscript for important intellectual 
content

Joyce Baard: study concept and design, critical revision 
of the manuscript for important intellectual content

Source of funding: This registry is funded by the Société 
Internationale d’Urologie (SIU), 1155 Robert-Bourassa 
Blvd, Suite 1012, Montréal, Québec, Canada.

Ethics approval: Regional Medical Research Ethics 
Committee, Institutional Review Board (IRB) or a 
waiver for consent was obtained at each participating 
center prior to subject enrollment.

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103SIUJ.ORG SIUJ  •  Volume 2, Number 2  •  March 2021

A Global Perspective of Stenting After Ureteroscopy: An Observational Multicenter Cohort Study

http://dx.doi.org/10.1016/j.euf.2017.04.001
http://dx.doi.org/10.1016/j.euf.2017.04.001
http://www.siuj.org


APPENDIX 1. 
Participating research centres

Institute Country Principal Investigator

1. Shanghai Changhai Hospital, Second Military Medical University China Yinghao Sun

2. Ningbo First Hospital, The Affiliated Hospital of Ningbo University China Yue Cheng

3. The First Affiliated Hospital of Guangzhou Medical University and G 
uangdong Key Laboratory of Urology

China Guohua Zeng

4. Renji Hospital, School of Medicine, Shanghai Jiao Tong University China Wei Xue

5. Tongji Hospital, Tongji Medical College, Huazhong University of Science and 
Technology

China Lei Cui

6. Guangdong Second Provincial General Hospital, The Third Clinical  
Medical College of Southern Medical University.

China Guosheng Yang

7. Sismanoglio General Hospital Greece Athanasios Papatsoris

8. Aretaieion Academic Hospital Greece Athanasios Dellis

9. Aristotle University, 1st Department of Urology, Thessaloniki Greece Anastasios Anastasiadis

10. University of Crete, Department of Urology Greece Charalampos Mamoulakis

11. University Hospital of Larissa, Department of Urology Greece Stavros Gravas

12. Jawahar Lal Nehru (JLN) Medical College India Rohit Ajmera

13. Kulkarni Reconstructive Urology Center India Sanjay Kulkarni

14. Sanglah Hospital, Department of Urology, Udayana University Indonesia Kadek Budi Santosa

15. Sardjito Hospital, Gadjah Mada University, Department of Urology, Jogjakarta Indonesia Indrawarman Soeroharjo

16. Cipto Mangunkusumo Hospital, Department of Urology, University of Indonesia Indonesia Nur Rasyid

17. Dr. Soetomo Hospital, Department of Urology, Airlangga University Indonesia Johan Renaldo

18. Hasan Sadikin Hospital, Department of Urology, Padjajaran University Indonesia Safendra Siregar

19. Saiful Anwar Hospital, Department of Urology, Brawijaya University Indonesia Taufiq Nur Budaya

20. Shahid Beheshti Hospital, Hamadan University of Medical Sciences Iran Seyed Habibollah Mousavibahar

21. University of Basra - College of Medicine, Department of Urology Iraq Murtadha Almusafer

22. Pandya Memorial Hospital Kenya Sundeep Chavda

23. University of Malaya Medical Centre Malaysia Teng Aik Ong

24. Selayang Hospital Malaysia Rohan Malek

25. Sarawak General Hospital Malaysia Guan Chou Teh

continued on page 105

104 SIUJ  •  Volume 2, Number 2  •  March 2021 SIUJ.ORG

ORIGINAL RESEARCH

http://www.siuj.org


APPENDIX 1. 
Participating research centres

Institute Country Principal Investigator

26. Kuala Lumpur Hospital Malaysia Vijayan Manogran

27. Serdang Hospital Malaysia Saiful Azli

28. St. John Clinical Hospital of Emergency, Department of Urology Romania Petrisor Geavlete

29. International Medical Center Saudi Arabia Raed A. Azhar

30. King Abdulaziz University Saudi Arabia Raed A. Azhar

31. Prince Sultan Military Medical City - Scientific Research Center Saudi Arabia Ali Obied

32. Sefako Makgatho Health Sciences University South Africa Shingai Mutambirwa

33. SMG-SNU Boramae Medical Center South Korea Sung Yong Cho

34. National Taiwan University Hospital, Department of Urology Taiwan Yeong-Shiau Pu

35. En Chu Kong Hospital, Department of Urology Taiwan Chung-Cheng Wang

36. Cardinal Tien Hospital, Department of Urology Taiwan Hsu-Che Huang

37. Kaohsiung Veterans General Hospital, Division of Urology,  
Department of Surgery

Taiwan Chia-Cheng Yu

38. University of Health Sciences, Dept of Urology, Bagcilar Hospital Turkey Emrah Yuruk

39. 9 Eylul University, Department of Urology Turkey Guven Aslan

40. Gazi University School of Medicine, Department of Urology, Ankara Turkey Bora Küpeli

41. Baskent University, Faculty of Medicine, Department of Urology Turkey M. Ilteris Tekin

42. Hacettepe University, Department of Urology, Ankara Turkey Cenk Y. Bilen

43. Istanbul Medipol University, Department of Urology Turkey Selcuk Guven

44. Cerrahpasa School of Medicine, Istanbul University Turkey Bulent Onal

45. Necmettin Erbakan University, Meram Medical School Turkey Mehmet Balasar

46. University of Çukurova, Department of Urology, Adana Turkey Ibrahim Atilla Aridogan

47. Konya Meram Education & Research Hospital Turkey Mahmud Zahid Ünlü

48. Bulent Ecevit University, Department of Urology Turkey N. Aydin Mungan

49. Selcuk University Selcuklu Medical School Turkey Mehmet Kaynar

50. University of Minnesota, Department of Urology United States Michael Borofsky

, Cont’d

105SIUJ.ORG SIUJ  •  Volume 2, Number 2  •  March 2021

A Global Perspective of Stenting After Ureteroscopy: An Observational Multicenter Cohort Study

http://www.siuj.org

