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Trial registered on ANZCTR


Registration number
ACTRN12616000865415
Ethics application status
Approved
Date submitted
28/04/2016
Date registered
1/07/2016
Date last updated
1/07/2016
Type of registration
Retrospectively registered

Titles & IDs
Public title
Does A Retropulsion Prevention Device Equalize The Surgical Success of Ho:YAG Laser and Pneumatic Lithotripters for Upper Ureteral Stones?
Scientific title
Does A Retropulsion Prevention Device Equalize The Surgical Success of Ho:YAG Laser and Pneumatic Lithotripters for Upper Ureteral Stones? A Prospective Randomized Study
Secondary ID [1] 289092 0
None
Universal Trial Number (UTN)
U1111-1182-3895
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Upper ureteral stones 298551 0
Condition category
Condition code
Renal and Urogenital 298634 298634 0 0
Other renal and urogenital disorders
Surgery 298830 298830 0 0
Surgical techniques

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients were treated with pneumatic(comparator) and Ho:YAG laser(intervention) lithotripters in group-1 and group-2, respectively. Pneumatic lithotripsy was performed in 130 patients and laser lithotripsy was performed in 130 patients. Two patients in group-2 were excluded due to inappropriate follow-up.
Ureteroscopy and lithotripsy were performed under spinal anesthesia for all patients. The surgeries were performed by the same surgical team (consultant urologist). Semi-rigid 7.5 or 9.5 Fr ureterorenoscopes (Richard Wolf, Knittlingen, Germany) were used for ureteroscopy under lithotomy position. Initially, a hydrophilic guidewire for safety was inserted into the ureter under fluoroscopy or direct vision. After that, a Stone-coneTM Nitinol Retrieval Coin (Boston Scientific, Marlborough, MA, USA) was placed for retropulsion prevention but not activated. Thereafter, the stone cone was opened under direct vision or fluoroscopy and lithotripsy was performed with Ho:YAG laser (Sphinx 30 Minimally Invasive Surgical Laser, LISA laser, Pleasanton, CA, USA) lithotripter for group-2. For group-2, 365 microm laser fibers were used and lithotripsy was performed with 1.0-2.0 Joule 5-10 Hz (5-20 Watt) settings. Treating surgeon decided the adjustments of energy setting on the basis of stone characteristics during the surgery. At the end of efficient fragmentation, extraction of the stone fragments was performed with stone forceps and the Stone-coneTM was closed and withdrawn. Approximate duration of surgery was 48 minutes. Flexible ureterorenoscopy was not performed in any of patients simultaneously. A double–J stent was inserted for two weeks in patients with residual stone fragments, bleeding and ureteral edema.
Intervention code [1] 294599 0
Treatment: Devices
Intervention code [2] 295133 0
Treatment: Surgery
Comparator / control treatment
Patients were treated with pneumatic(comparator) and Ho:YAG laser(intervention) lithotripters in group-1 and group-2, respectively. Pneumatic lithotripsy was performed in 130 patients and laser lithotripsy was performed in 130 patients. Two patients in group-2 were excluded due to inappropriate follow-up.
Ureteroscopy and lithotripsy were performed under spinal anesthesia for all patients. The surgeries were performed by the same surgical team (consultant urologist). Semi-rigid 7.5 or 9.5 Fr ureterorenoscopes (Richard Wolf, Knittlingen, Germany) were used for ureteroscopy under lithotomy position. Initially, a hydrophilic guidewire for safety was inserted into the ureter under fluoroscopy or direct vision. After that, a Stone-coneTM Nitinol Retrieval Coin (Boston Scientific, Marlborough, MA, USA) was placed for retropulsion prevention but not activated. Thereafter, the stone cone was opened under direct vision or fluoroscopy and lithotripsy was performed with pneumatic (Vibrolith Pneumatic Lithotripter, ELMED, Turkey) lithotripter for group-1. For group-1, lithotripsy was started with 4-5 bars and then the frequency of the lithotripter was increased if necessary. The frequency settings were 50-500 pulse/minute. Treating surgeon decided the adjustments of power setting on the basis of stone characteristics during the surgery. At the end of efficient fragmentation, extraction of the stone fragments was performed with stone forceps and the Stone-coneTM was closed and withdrawn. Approximate duration of surgery was 46 minutes. Flexible ureterorenoscopy was not performed in any of patients simultaneously. A double–J stent was inserted for two weeks in patients with residual stone fragments, bleeding and ureteral edema.
Control group
Active

Outcomes
Primary outcome [1] 298129 0
Patients were evaluated on the first postoperative day before discharge with plain x-ray and ultrasonography for residual stone fragments and hydronephrosis. Patients with residual fragments greater than or equal to 4mm were accepted as surgical failures. Patients with stone-free status or with residual fragments <4mm were accepted as surgical success.
Timepoint [1] 298129 0
Postoperative first day.
Secondary outcome [1] 323241 0
Requirement for auxiliary procedures one month after surgery, assessed by x-ray and ultrasonography. A decision was made one month after surgery for auxiliary procedures.
Timepoint [1] 323241 0
One month after surgery

Eligibility
Key inclusion criteria
Patients between 18 and 82 with obstructive, radioopaque and primary unilateral upper ureteral stones were included in this study.
Minimum age
18 Years
Maximum age
82 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Exclusion criterias were abnormal coagulation profile, previous SWL, bilateral ureteral stones, radiolucent stones, likelihood of spontaneous stone passage, and presence of a non-functioning kidney. Patients with narrow ureters that required stenting and with push-back of the stone before activation of the stone cone were excluded. Stone localization in the fluoroscopic stone immediately prior to the surgery was compared with preoperative stone localizations. Patients with changing stone localizations were excluded from the study.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation is not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Randomization was arranged with “=Rand( )” formula in Microsoft Office Excel 2007 (Microsoft Corporation, Redmond, WA, USA) software. Patients were randomly allocated with the use of a computer-generated schedule to receive pneumatic or Ho:YAG laser lithotripsy. Single-blinding was used for this study.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s


Intervention assignment
Parallel
Other design features
Phase
Type of endpoint/s
Statistical methods / analysis
For calculating a priori sample size, we could not find a similar study comparing two different energy sources with the use of a retropulsion prevention device for upper ureteral stones in the literature and decided to perform post hoc analysis. Power value was 96.4% for an effect size value (0.2343563) that was calculated for a surgical success rate of 81.5% in the pneumatic group and 90.6% in the laser group. With this power value it was found that the sample size was sufficient.
The normal distribution assumption was tested with Kolmogorov-Smirnov and Shapiro-Wilk tests. Kurtosis and skewness values were also examined. It was found that the data were normally distributed for both groups. Data are expressed as mean+/-SD for continuous variables and number and/or percentage for categorical variables.
In this study, Pearson’s Chi-square test was used for the categorical variables and independent t-test was used for continuous variables. In all tests, p<0.05 was considered to indicate statistical significance.
Statistical Package for Social Sciences version 21.0 Software for Windows (IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp. USA) was used for descriptive statistics, independent t-test and Chi-Square tests. G-power 3.1 (Department of Psychology, University of Düsseldorf, Germany) was used for post hoc power analysis.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
1/04/2014
Date of last participant enrolment
Anticipated
Actual
1/12/2015
Date of last data collection
Anticipated
Actual
8/03/2016
Sample size
Target
200
Accrual to date
Final
258
Recruitment outside Australia
Country [1] 7842 0
Turkey
State/province [1] 7842 0
Kirsehir

Funding & Sponsors
Funding source category [1] 293467 0
University
Name [1] 293467 0
Ahi Evran University
Country [1] 293467 0
Turkey
Primary sponsor type
University
Name
Ahi Evran University, Academical Researches Supporting Unit
Address
Ahi Evran University, Academical Researches Supporting Unit, Bagbasi Campus, 40100, Kirsehir/TURKEY
Country
Turkey
Secondary sponsor category [1] 292290 0
None
Name [1] 292290 0
Address [1] 292290 0
Country [1] 292290 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 294909 0
Kirikkale University Ethics committee
Ethics committee address [1] 294909 0
Kirikkale University Medicine Faculty, Ethics Committee, Ankara Street, 71100. Kirikkale/TURKEY.
Ethics committee country [1] 294909 0
Turkey
Date submitted for ethics approval [1] 294909 0
10/02/2013
Approval date [1] 294909 0
11/03/2013
Ethics approval number [1] 294909 0
06/02-11.03.2013

Summary
Brief summary
Purpose: To establish if a retropulsion prevention device for ureteral stones equalizes surgical success and push-back rates of Ho:YAG laser and pneumatic lithotripters for upper ureteral stones.
Materials and Methods: Patients with upper ureteral stones (n=267) were treated endoscopically at the Department of Urology between April 2014 and December 2015. Patients were randomly assigned to pneumatic and Ho:YAG laser lithotripters as group-1 and group-2, respectively. Among the 267 patients three and four patients were excluded due to changing stone localizations in group-1 and group-2, respectively. Pneumatic lithotripsy was performed in 130 patients and laser lithotripsy was performed in 130 patients. Two patients in group-2 were excluded due to inappropriate follow-up.Lithotripsy was performed with Stone-coneTM in both groups.

Results: The surgical success rate on the first postoperative day was 81.5% (n=106) and 90.6% (n=116) for group-1 and group-2, respectively, and the difference between the groups was statistically significant (p<0.05). The relation between stone size and surgical success was statistically significant for both groups (p<0.01). Surgical success for the stones closer than 2cm to the UPJ was 23.1% for the pneumatic group versus 64% for the laser group (p<0.01). Lithotripsy time was significantly longer in group-2 (16.48+/-4.74 min.) than group-1 (12.24+/-3.95 min.) (p<0.01).

Conclusions: Ho:YAG laser can fragment the stone in place in the low-power settings and this provides high success rates with the use of a push-back prevention device, especially for very high level upper ureteral stones. Many clinics may not have unlimited access to flexible ureteroscopy. Ho:YAG laser lithotripsy is more successful than pneumatic lithotripsy for upper ureteral stones, and a retropulsion prevention device does not equalize the surgical success of Ho:YAG laser and pneumatic lithotripters for upper ureteral stones.
Trial website
Trial related presentations / publications
.
Public notes

Contacts
Principal investigator
Name 65434 0
Dr Sahin Bagbanci
Address 65434 0
Department of Urology, Faculty of Medicine, Ahi Evran University, Bagbasi Campus, 40100. Kirsehir/TURKEY.
Country 65434 0
Turkey
Phone 65434 0
+903862134517
Fax 65434 0
Email 65434 0
[email protected]
Contact person for public queries
Name 65435 0
Dr Sahin Bagbanci
Address 65435 0
Department of Urology, Faculty of Medicine, Ahi Evran University, Bagbasi Campus, 40100. Kirsehir/TURKEY.
Country 65435 0
Turkey
Phone 65435 0
+903862134517
Fax 65435 0
Email 65435 0
[email protected]
Contact person for scientific queries
Name 65436 0
Dr Sahin Bagbanci
Address 65436 0
Department of Urology, Faculty of Medicine, Ahi Evran University, Bagbasi Campus, 40100. Kirsehir/TURKEY.
Country 65436 0
Turkey
Phone 65436 0
+90 505 445 00 75
Fax 65436 0
Email 65436 0
[email protected]

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