Nephrolithiasis
Conditions
Brief summary
This is a randomized prospective study to compare stone free rates and operative efficiency of two laser systems used during retrograde intrarenal surgery for kidney stone disease: 1. A superpulsed thulium fiber laser (thulium) 2. A pulse modulated high power holmium laser (Holmium)
Detailed description
This is a randomized prospective study. The purpose is to compare the stone free rate and operative efficiency of two leading contemporary laser systems used during retrograde intrarenal surgery for kidney stone disease. The researchers will compare the following two systems: 1. A superpulsed thulium fiber laser (thulium) 2. A pulse modulated high power holmium laser (Holmium) The researchers will recruit 82 subjects undergoing single stage unilateral ureteroscopy for renal stones with a volume between \>5mm to \< 20 mm. Subjects will be randomized to undergo lithotripsy with either Ho:YAG or Thulium lasers. All subjects will undergo surgical interventions that abide by broadly accepted guidelines and standards of care. The primary outcome is stone free rate evaluated by postoperative CT scans done 6-12 weeks after surgery.
Interventions
DEVICEThulium Fibre Laser
The TFL is a relatively new laser in the field of urology. First introduced on the market in 2017, it offers theoretically superior stone dusting qualities and smaller fiber sizes to allow for better irrigation.
The Ho:YAG is currently the most commonly used laser in the field of urology and for the better part of the last 3 decades has been considered the gold standard for laser lithotripsy.
Sponsors
Icahn School of Medicine at Mount Sinai
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Undergoing single stage unilateral RIRS for total stone burden volume \>5mm to \< 20 mm * Preoperative CT scan for baseline measurements
Exclusion criteria
* Anatomic variations: horseshoe kidney, pelvic kidney, ptotic kidney, urinary diversion or ureteral stricture * Ureteral stent * Uric acid component \>50% on stone analysis * Prior ureteroscopy within 6 weeks of current surgery * Irreversible coagulopathy * Urothelial tumor(s), direct extraction of the stone(s) without needing laser lithotripsy, and failure to reach the stone in the upper urinary tract with the ureteroscope.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Stone Free Status | 6-12 weeks postoperative | Stone free status as determined by 6-12 week postoperative CT scan to assess laser efficacy |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Fragmentation Speed | Intraoperatively (Day 1) | Fragmentation speed is calculated by dividing stone volume by lasing time (mm3/sec). This is a measure of how quickly the laser breaks down the kidney stones. |
| Lasing Activity | Intraoperatively (Day 1) | Lasing activity is calculated by dividing lasing time by lithotripsy operative time (%). This measures the percentage of time during surgery that the surgeon is actively using the laser to break down kidney stones. |
| Energy Utilization | Intraoperatively (Day 1) | Energy utilization is calculated by dividing laser energy by stone volume (J/mm3). This is a measure of how much laser energy is needed to break down a stone. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Thulium Fibre Laser (TFL) Patients who are randomized to undergo ureteroscopic laser lithotripsy with the Thulium fibre laser (TFL)
Thulium Fibre Laser: The TFL is a relatively new laser in the field of urology. First introduced on the market in 2017, it offers theoretically superior stone dusting qualities and smaller fiber sizes to allow for better irrigation. | 33 |
| Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) Patients who are randomized to undergo ureteroscopic laser lithotripsy with the Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) laser
Holmium:Yttrium-Aluminum-Garnet: The Ho:YAG is currently the most commonly used laser in the field of urology and for the better part of the last 3 decades has been considered the gold standard for laser lithotripsy. | 33 |
| Total | 66 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 8 | 8 |
Baseline characteristics
| Characteristic | Thulium Fibre Laser (TFL) | Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) | Total |
|---|---|---|---|
| Age, Continuous | 62.0 years | 60.0 years | 60.5 years |
| Body Mass Index (BMI) | 27.2 kg/m^2 | 26.6 kg/m^2 | 26.8 kg/m^2 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 4 Participants | 0 Participants | 4 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 19 Participants | 27 Participants | 46 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 10 Participants | 6 Participants | 16 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 1 Participants | 4 Participants | 5 Participants |
| Race (NIH/OMB) Black or African American | 0 Participants | 2 Participants | 2 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 10 Participants | 6 Participants | 16 Participants |
| Race (NIH/OMB) White | 22 Participants | 21 Participants | 43 Participants |
| Sex: Female, Male Female | 10 Participants | 8 Participants | 18 Participants |
| Sex: Female, Male Male | 23 Participants | 25 Participants | 48 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 33 | 0 / 33 |
| other Total, other adverse events | 0 / 33 | 0 / 33 |
| serious Total, serious adverse events | 0 / 33 | 0 / 33 |
Outcome results
Primary
Number of Participants With Stone Free Status
Stone free status as determined by 6-12 week postoperative CT scan to assess laser efficacy
Time frame: 6-12 weeks postoperative
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Thulium Fibre Laser (TFL) | Number of Participants With Stone Free Status | 27 Participants |
| Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) | Number of Participants With Stone Free Status | 26 Participants |
Secondary
Energy Utilization
Energy utilization is calculated by dividing laser energy by stone volume (J/mm3). This is a measure of how much laser energy is needed to break down a stone.
Time frame: Intraoperatively (Day 1)
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Thulium Fibre Laser (TFL) | Energy Utilization | 13.6 J/mm3 |
| Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) | Energy Utilization | 17.7 J/mm3 |
Secondary
Fragmentation Speed
Fragmentation speed is calculated by dividing stone volume by lasing time (mm3/sec). This is a measure of how quickly the laser breaks down the kidney stones.
Time frame: Intraoperatively (Day 1)
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Thulium Fibre Laser (TFL) | Fragmentation Speed | 0.25 mm3/sec |
| Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) | Fragmentation Speed | 0.29 mm3/sec |
Secondary
Lasing Activity
Lasing activity is calculated by dividing lasing time by lithotripsy operative time (%). This measures the percentage of time during surgery that the surgeon is actively using the laser to break down kidney stones.
Time frame: Intraoperatively (Day 1)
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Thulium Fibre Laser (TFL) | Lasing Activity | 58.0 percent of time using laser |
| Holmium:Yttrium-Aluminum-Garnet (Ho:YAG) | Lasing Activity | 46.1 percent of time using laser |