Use of Antiretropulsion Device in Laser Lithotripsy

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00859170
Recruitment Status : Terminated (Change in priorities occurred)
First Posted : March 10, 2009
Last Update Posted : January 8, 2010
Information provided by:
Percutaneous Systems, Inc.

Brief 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.

Condition or disease Intervention/treatment Phase
Kidney Stones Device: Accordion device Not Applicable

Detailed 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.

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 100 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Treatment
Official Title: Use of the Accordion Stone Management Device in Laser Lithotripsy
Study Start Date : February 2009
Estimated Primary Completion Date : June 2009
Estimated Study Completion Date : August 2009

Arm Intervention/treatment
Experimental: Accordion use
Use of an Accordion device during the lithotripsy.
Device: Accordion device
an antiretropulsion device
Other Name: Accordion Stone Management Device PA1205-06-10

No Intervention: Control Group
Patients who will not have an Accordion device used during lithotripsy.

Primary Outcome Measures :
  1. Incidence of retropulsion or migration of the stone or fragments [ Time Frame: Two months ]

Secondary Outcome Measures :
  1. Elapsed times for placing the safety guidewire [ Time Frame: Two months ]
  2. Fragmenting the stone into pieces no larger than 1 mm in size [ Time Frame: Two months ]
  3. Removing the fragments from the ureter [ Time Frame: Two months ]
  4. Procedure time [ Time Frame: Two months ]

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Ages Eligible for Study:   18 Years to 90 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00859170

United States, California
Kaiser Permanente Bellflower Hospital
Downey, California, United States, 90706
United States, New York
New York University Medical Center
New York, New York, United States, 10016
United States, Texas
USMD Hospital
Arlington, Texas, United States, 76017
Sponsors and Collaborators
Percutaneous Systems, Inc.
Study Director: Thomas T Lawson, PhD Percutaneous Systems, Inc.

Publications of Results:
Responsible Party: Thomas Lawson, PhD / VP, Clinical & Regulatory Affairs, Percutaneous Systems, Inc. Identifier: NCT00859170     History of Changes
Other Study ID Numbers: 08-001
First Posted: March 10, 2009    Key Record Dates
Last Update Posted: January 8, 2010
Last Verified: January 2010

Keywords provided by Percutaneous Systems, Inc.:
kidney stones
laser lithotripsy

Additional relevant MeSH terms:
Kidney Calculi
Kidney Diseases
Urologic Diseases
Urinary Calculi
Pathological Conditions, Anatomical