Kidney Stones
Conditions
Keywords
Kidney Stones, Renal Calculi
Brief summary
Percutaneous nephrolithotomy (PNL), in conjunction with intracorporeal lithotripsy, allows for the rapid removal of any kidney stone regardless of size. Currently, the choice of intracorporeal lithotripters includes ultrasonic, pneumatic, and combined ultrasonic/pneumatic energy sources. Recently, a novel dual probe design as been introduced by Cybersonics of Erie, Pennsylvania. This dual probe intracorporeal lithotrite is called the Cyberwand, and is composed of a fixed inner probe vibrating at an ultrasonic frequency with an outer probe vibrating at about 1,000 Hz. As this new design has the potential to revolutionize intracorporeal lithotripsy, we intend to compare this novel technology to currently available lithotripsy technology in a randomized clinical trial.
Detailed description
Percutaneous nephrolithotomy (PNL) is used to remove large and complex stones from the upper urinary tract. Intracorporeal lithotripsy is an integral part of PNL. Commercially available intracorporeal lithotripsy modalities include ultrasonic, pneumatic, and combined ultrasonic and pneumatic models. Each modality has its inherent advantages and disadvantages. Ultrasonic lithotrites are capable of fragmenting stones while concomitantly suctioning out fragments. Unfortunately some stones are hard enough to resist fragmentation from ultrasonic lithotripsy. Pneumatic lithotrites are able to fragment all stones regardless of hardness, but this modality is unable to suction out stone pieces at the same time fragmentation is occurring. The newest lithotrite which combines both ultrasonic and pneumatic components is capable of fragmenting any stone, but also has some inherent limitations. The handpiece of the lithotripsy device is somewhat cumbersome, the suction component can clog, and the device has overheated at the maximal settings (Kuo et al). Current intracorporeal lithotrites, while functional, can certainly be improved. Recently, a novel dual probe design has been introduced by Cybersonics of Erie, PA. This dual probe intracorporeal lithotrite is called the Cyberwand and is composed of a fixed inner probe vibrating at an ultrasonic frequency with an outer probe vibrating at about 1,000 Hz. As this new design has the potential to revolutionalize intracorporeal lithotripsy, we intend to compare this novel technology to currently available lithotripsy technology in a randomized clinical trial.
Interventions
DEVICECyberwand
FDA approved - dual probe intracorporeal lithotrite
DEVICEsingle probe ultrasonic
FDA-approved - single probe ultrasonic
Sponsors
Indiana Kidney Stone Institute
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patient of Methodist Urology in Indianapolis, IN * Undergoing percutaneous nephrolithotomy for calculi greater than 2 cm * Age 18 years or older * Stone easily visible/measurable on kidney, ureters and bladder (KUB) or computed tomography (CT) scan preoperatively
Exclusion criteria
* Radiolucent stones * Size of largest stone less than 2 cm * Pregnancy * Inability to give informed consent * Multiple percutaneous access anticipated * Active urinary tract infection * Recent (within last 3 months) extracorporeal shock wave lithotripsy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Kidney Stone Clearance Rate | 6 months | stone clearance rate calculated in mm\^2/min per protocol specification |
Countries
Canada, United States
Participant flow
Recruitment details
Patients undergoing percutaneous nephrolithotomy with a target stone size greater than 2cm
Participants by arm
| Arm | Count |
|---|---|
| Cyberwand Cyberwand
Cyberwand : FDA approved - dual probe intracorporeal lithotrite | 34 |
| Currently Available Lithotripsy Techology Currently available lithotripsy technology
single probe ultrasonic : FDA-approved - single probe ultrasonic | 36 |
| Total | 70 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | surgical access pbs; device issues | 9 | 4 |
Baseline characteristics
| Characteristic | Cyberwand | Currently Available Lithotripsy Techology | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 6 Participants | 5 Participants | 11 Participants |
| Age, Categorical Between 18 and 65 years | 28 Participants | 31 Participants | 59 Participants |
| Region of Enrollment Canada | 10 participants | 10 participants | 20 participants |
| Region of Enrollment United States | 24 participants | 26 participants | 50 participants |
| Sex: Female, Male Female | 14 Participants | 14 Participants | 28 Participants |
| Sex: Female, Male Male | 20 Participants | 22 Participants | 42 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 10 / 34 | 15 / 36 |
| serious Total, serious adverse events | 0 / 34 | 0 / 36 |
Outcome results
Primary
Kidney Stone Clearance Rate
stone clearance rate calculated in mm\^2/min per protocol specification
Time frame: 6 months
Population: Sample size calculations were performed using a two-sided Student's t-test with a power of 90% and a significance level of α = 0.05
| Arm | Measure | Value (MEAN) |
|---|---|---|
| Cyberwand | Kidney Stone Clearance Rate | 61.9 mm^2/min |
| Currently Available Lithotripsy Techology | Kidney Stone Clearance Rate | 75.8 mm^2/min |