Use of Antiretropulsion Device in Laser Lithotripsy

Kidney Stones Clinical Trial

Official title:

Use of the Accordion Stone Management Device in Laser Lithotripsy

Clinical Trial Details — Status: Terminated

Administrative data

• NCT number: NCT00859170
• Other study ID #: 08-001
• Status: Terminated
• Phase: N/A
• First received: March 5, 2009
• Last updated: January 6, 2010
• Start date: February 2009
• Est. completion date: August 2009

Study information

• Verified date: January 2010
• Source: Percutaneous Systems, Inc.
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

The objectives of this post-market evaluation are

1. to assess the capacity of the procedure to be completed with use of only a semi-rigid ureteroscope, without requiring use of a flexible ureteroscope

2. to compare the rate of retropulsion and the time required to complete the lithotripsy in patients in which the Accordion device is used in contrast to when such a device is not employed.

Description:

In North America, ureteroscopic-guided lithotripsy with the holmium:yttrium-aluminum-garnet (Ho:YAG) laser has increased in clinical utility owing to its capacity to fragment stones of all compositions. However, with the application of the light energy, retropulsion of the stone is possible due to the combined effects of fragment ejection, water vaporization, and cavitation bubble expansion then collapse. Reducing the laser energy and using laser fibers with small diameters are options to address such a consequence, but these changes have the potential to reduce the efficacy of the laser treatment.

Movement of stones and stone fragments during laser lithotripsy also can be caused by the application of irrigation during the procedure. Irrigation is necessary in order to maintain clear visualization of the targeted stone during lithotripsy, and yet irrigation flow pressure can push stones away from the laser tip, requiring repositioning of the laser, and, in the presence of hydrodilation of the ureter, cause the stone to float up to the renal pelvis or into the kidney itself. In such a situation the physician may be required to use more specialized instruments, adding to the complexity and cost of the procedure. As a result, physicians monitor irrigation closely and will reduce the flow if retropulsion of the stone or fragments occurs.

Retropulsion of stones and stone fragments during laser lithotripsy has been reported in up to 24% of patients and can cause prolonged operative times due to near-constant repositioning of the laser fiber between firings, and as well as result in additional treatment methods, making available a flexible ureteroscope, with its associated costs, and additional cost associated with an extended procedure.

A novel occluding guidewire, the Accordion Stone Management Device, has been developed that can be advanced up the ureter and past the stone. Once past the stone, an occlusion film is engaged within the lumen of the ureter in order to limit retropulsion of the stone and its fragments, irrespective of the laser energy, flow rate of irrigation, or dilation of the ureter. Reduction of stone fragment movement has the potential to reduce operative time and increase stone-free rates within this population.

Recruitment information / eligibility

• Status: Terminated
• Enrollment: 100
• Est. completion date: August 2009
• Est. primary completion date: June 2009
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years to 90 Years

Eligibility

Inclusion Criteria:

• Solitary ureteral stone in the distal or medial ureter, 10 mm in diameter or less, as demonstrated by preoperative CT or IVP imaging and are 18 years of age or older.

Exclusion Criteria:

• Patients will be excluded from this study if they have active urinary tract infection, or, if female, pregnant, or has clinical evidence of sepsis, or a single or nonfunctioning kidney, or coagulopathy, or congenital ureteral abnormality, or previous ureteral reimplantation, or presence of any degree of ureteral stricture distal to the stone, as determined before or during the procedure, or inability to sign informed consent.

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Single Blind (Subject), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Kidney Calculi
• Kidney Stones
• Nephrolithiasis

Intervention

Device:
• Accordion device
an antiretropulsion device

Locations

Country	Name	City	State
United States	USMD Hospital	Arlington	Texas
United States	Kaiser Permanente Bellflower Hospital	Downey	California
United States	New York University Medical Center	New York	New York

Sponsors (1)

Lead Sponsor	Collaborator
Percutaneous Systems, Inc.

Country where clinical trial is conducted

United States, 

References & Publications (4)

Bapat SS, Pai KV, Purnapatre SS, Yadav PB, Padye AS. Comparison of holmium laser and pneumatic lithotripsy in managing upper-ureteral stones. J Endourol. 2007 Dec;21(12):1425-7. doi: 10.1089/end.2006.0350. — View Citation

Ilker Y, Ozgür A, Yazici C. Treatment of ureteral stones using Holmium:YAG laser. Int Urol Nephrol. 2005;37(1):31-4. — View Citation

Maislos SD, Volpe M, Albert PS, Raboy A. Efficacy of the Stone Cone for treatment of proximal ureteral stones. J Endourol. 2004 Nov;18(9):862-4. — View Citation

Manohar T, Ganpule A, Desai M. Comparative evaluation of Swiss LithoClast 2 and holmium:YAG laser lithotripsy for impacted upper-ureteral stones. J Endourol. 2008 Mar;22(3):443-6. doi: 10.1089/end.2007.0288. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Incidence of retropulsion or migration of the stone or fragments		Two months	No
Secondary	Elapsed times for placing the safety guidewire		Two months	No
Secondary	Fragmenting the stone into pieces no larger than 1 mm in size		Two months	No
Secondary	Removing the fragments from the ureter		Two months	No
Secondary	Procedure time		Two months	No