The Alternating Bidirectional Versus The Standard Approach During Shock Wave Lithotripsy For Renal And Upper Lumbar Ureteric Stones

The Alternating Bidirectional Versus The Standard Approach During Shock Wave Lithotripsy For Renal And Upper Lumbar Ureteric Stones. A Randomized Clinical Trial

compare the outcomes of SWL for renal and upper lumbar ureteric stones using the alternating bidirectional approach versus the standard approach.

Study Overview

• Status: Unknown
• Conditions: Urologic Diseases; Stones, Kidney; Stone, Urinary; Shock Wave Lithotripsy
• Intervention / Treatment: Procedure: Bidirectional Shock Wave Lithotripsy; Procedure: Standard Shock Wave Lithotripsy

Detailed Description

Shock wave lithotripsy (SWL) has been considered the preferred method for treating upper urinary tract stones since 1980s due to its minimally invasive characters and low morbidity. The overall stone free rates have been reported to be 80% to 90% .

In the presence of pregnancy, untreated urinary tract infection, decompensated coagulopathy, uncontrolled arrhythmia and abdominal aortic aneurysm, other treatment methods should be considered .

SWL is associated with some complications. The most common complications of SWL are renal colic (40%), gross hematuria (32%), urinary obstruction (30.9%), symptomatic bacteriuria (9.7%) and perirenal hematoma or subclinical subcapsular hematoma (4.6%).

There are many factors affecting the success of SWL as patient age, sex, body mass index (BMI), stone size, site and number, radiological renal features, congenital renal anomalies and presence of double-J (DJ) ureteric stent .

Regarding the renal stones, stones smaller than 10 mm had a success rate of 90%, while those larger than 10 mm had a success rate of 70%. Stones located in the renal pelvis and upper pole had a success rate of 87.3 and 88.5% respectively, while those located in the lower pole had a success rate of 69.5%. A single renal stone had a 78.3% success rate compared to 62.8% in multiple renal stones . Regarding the ureteric stones, stone size more than 10 mm was one of the strongest independent predictors of failure of SWL

Patients appear to have the best chance for successful SWL when they have small BMI and their stones are single and located in the renal pelvis . Skin to stone distance (SSD) measured by non-contrast computerized tomography scan (NCCT) has a significant role in the treatment of renal stones using SWL. Slow shock wave rate (60/min) is associated with increase in the success rate and decrease in pain, complication and number of session to achieve success when compared to rapid shock wave rate (120/min)

Some techniques were developed to increase the efficacy of SWL. In 1999, the bidirectional synchronous twin-pulse technique with variable angles between the shock wave reflectors was developed and it improved the quality and rate of stone disintegration in vitro and it was more effective than the traditional single generator and also it decreases the overall treatment times

The TWINHEADS 101 lithotripter comprises two identical under and over table reflectors to permit synchronous shock waves emission from two perpendicular directions to the same focal point. This technique intensifies and localizes the cavitations effects by the interacting focal zones of both reflectors, resulting in a better quality and rate of stone disintegration, especially with a right angle between the axes of the reflectors.

The first prospective clinical study was done in 2005 regarding synchronous twin-pulse SWL and it seems safe and effective for treating patients with renal and upper ureteric stones. The stone-free rate was 74% after one session and 100% after two sessions within a month

Based on the principle of the TWINHEADS lithotripter, we will use Dornier Gemini lithotripter to emit the shock waves from two different directions to the same focal point asynchronously for renal and upper lumbar ureteric stones.

• Study Type: Interventional
• Enrollment (Anticipated): 240
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Egypt
  • Mansoura, Egypt, 35516
    • Urology and nephrology center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Patient criteria:

  1. Ability to give informed consent.
  2. Normal laboratory profile as regarding serum creatinine, liver function, platelets count and prothrombin time.

• Stone criteria:

  1. Single renal stone less than two cm or upper lumbar ureteric stone less than one cm.
  2. Radio-opaque stones.

Exclusion Criteria:

1. Bleeding tendency.
2. Poor kidney function.
3. Pregnancy.
4. Abdominal aortic aneurysm.
5. Indwelling DJ ureteric stent or percutaneous nephrostomy tube (PCN).
6. Congenital anomalies of the urinary tract.
7. Untreated urinary tract infection.
8. Obstructed urinary tract distal to the stone.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Bidirectional Shock Wave Lithotripsy; alternating bidirectional (under and over table) approach	Procedure: Bidirectional Shock Wave Lithotripsy; the alternating bidirectional (under and over table) approach during SWL for renal and upper lumbar ureteric stones; Other Names: Bidirectional SWL
Active Comparator: Standard Shock Wave Lithotripsy; standard unidirectional approach	Procedure: Standard Shock Wave Lithotripsy; the standard unidirectional approach during SWL for renal and upper lumbar ureteric stones; Other Names: Standard SWL

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
stone free rate three months after the last session	residual less than 4 mm by non-contrast computerized tomography scan (NCCT)	18 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
severity of complications after SWL in both groups	Clavien-Dindo scale of surgical complications	18 months

Collaborators and Investigators

• Sponsor: Mansoura University

Publications and helpful links

General Publications

• Hegazy M, El-Assmy A, Ali-El-Dein B, Sheir KZ. The alternating bidirectional versus the standard approach during shock wave lithotripsy for upper lumbar ureteric stones: a randomized controlled trial. World J Urol. 2021 Jan;39(1):247-253. doi: 10.1007/s00345-020-03148-5. Epub 2020 Mar 23.

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2016
• Primary Completion (Anticipated): March 1, 2018
• Study Completion (Anticipated): March 1, 2018

Study Registration Dates

• First Submitted: July 29, 2017
• First Submitted That Met QC Criteria: August 7, 2017
• First Posted (Actual): August 9, 2017

Study Record Updates

• Last Update Posted (Actual): August 9, 2017
• Last Update Submitted That Met QC Criteria: August 7, 2017
• Last Verified: July 1, 2017

More Information

Terms related to this study

• Keywords: Bidirectional; Shock wave lithotripsy; Stones
• Additional Relevant MeSH Terms: Pathologic Processes; Kidney Diseases; Pathological Conditions, Anatomical; Ureteral Diseases; Urolithiasis; Shock; Urinary Calculi; Calculi; Kidney Calculi; Nephrolithiasis; Ureteral Calculi; Ureterolithiasis; Urologic Diseases
• Other Study ID Numbers: Bidirectional SWL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No