Laser Systems for Kidney Stones

Recruiting in Palo Alto (17 mi)

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Academic

Recruiting

Sponsor: University of California, San Diego

Disqualifiers: Concomitant stones, Prior procedures, Pregnancy, others

No Placebo Group

Trial Summary

What is the purpose of this trial?

This research study is being conducted to assess the ability and efficiency of two laser systems to break up kidney stones during ureteroscopy with laser lithotripsy for kidney stone treatment.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment Thulio Pulsed Thulium:YAG (p-Tm:YAG) for kidney stones?

Research shows that the SuperPulse Thulium Fiber Laser (SP TFL) is effective for breaking down kidney stones, with studies indicating it can be a viable alternative to the traditional Holmium:YAG laser. In one study, patients treated with SP TFL had no residual stones after 30 days, suggesting it is effective in achieving a stone-free state. ^{1 2 3 4 5}

Is the Thulium Fiber Laser safe for treating kidney stones?

Research on the Thulium Fiber Laser (TFL) for kidney stones shows it is being studied as a safe alternative to the Holmium:YAG laser, with studies focusing on its safety in procedures like retrograde intrarenal surgery (RIRS). Initial clinical experiences and comparisons with other lasers suggest it is generally safe for use in humans. ^{1 2 3 4 6}

How does the Thulium Fiber Laser treatment for kidney stones differ from other treatments?

The Thulium Fiber Laser (TFL) treatment for kidney stones is unique because it offers a broader range of pulse energy and frequency, allowing for more precise and efficient stone removal compared to the traditional Holmium:YAG laser. It also produces finer stone dust and has a higher energy absorption in water, which enhances safety and effectiveness during the procedure. ^{1 3 6 7 8}

Research Team

Eligibility Criteria

This trial is for individuals with kidney stones who can consent to treatment and are good candidates for a specific type of surgery called flexible ureteroscopy. Surgeons involved must be specialized in Endourology. Participants should have a single kidney stone or multiple stones totaling 7-20 mm in size, but those with certain urinary conditions, pregnancy, untreated UTI, other stones, prior surgeries or radiotherapy to the area cannot join.

Inclusion Criteria

Must be able to give consent

My surgeon is a trained specialist in Endourology.

I am considered fit for a specific kidney stone removal surgery.

Exclusion Criteria

I have a bladder condition due to nerve problems or a spinal cord injury.

Pregnancy

I currently have a urinary tract infection that hasn't been treated.

Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo ureteroscopic stone treatment using either the p-Tm:YAG or TFL laser systems

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment, including follow-up imaging

6-12 weeks

1-2 visits (in-person)

Treatment Details

Interventions

• Thulio Pulsed Thulium:YAG (p-Tm:YAG) (Laser Therapy)
• Thulium Fiber Laser (TFL) (Laser Therapy)

Trial Overview The study compares two laser systems used during ureteroscopy: Thulium Fiber Laser (TFL) and pulsed Thulium:YAG (p-Tm:YAG). It aims to determine which system is more effective at breaking up kidney stones during this minimally invasive procedure.

Participant Groups

Group I: p-Tm:YAG laser system Experimental Treatment 1 Intervention

This is a new laser system developed by Dornier, the Thulio pulsed Thulium:YAG (p-Tm:YAG)

Group II: TFL laser system Active Control 1 Intervention

The thulium fiber laser (TFL) has demonstrated effectiveness in this procedure.

Who Is Running the Clinical Trial?

University of California, San Diego

Lead Sponsor

Trials

1,215

Recruited

1,593,000+

Dr. Christopher Longhurst

University of California, San Diego

Chief Medical Officer since 2021

MD and MS in Medical Informatics from UC Davis

Patty Maysent

University of California, San Diego

Chief Executive Officer since 2016

MBA from Stanford University

Dornier MedTech Systems

Industry Sponsor

Trials

5

Recruited

340+

Findings from Research

The thulium fiber laser (TFL) in micro-pulse train (MPT) mode significantly increased the stone ablation rates for uric acid and calcium oxalate stones, achieving rates of 414 μg/s and 122 μg/s respectively, compared to lower rates with standard pulse trains.

Minimal stone retropulsion was observed with TFL operation, indicating safety in its application, while fiber degradation was noted to be higher with calcium oxalate stones, suggesting a need for further optimization in clinical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Enhanced thulium fiber laser lithotripsy using micro-pulse train modulation. Blackmon, RL., Irby, PB., Fried, NM.[2019]

The Thulium fiber laser (TFL) demonstrated longer ureter perforation times compared to the Holmium:YAG laser, suggesting it may be safer for use in lithotripsy procedures, with mean perforation times of 7.9, 3.8, and 1.8 seconds at pulse rates of 150, 300, and 500 Hz, respectively.

TFL showed reduced collateral damage to ureter tissue and stone baskets, with no damage observed at working distances greater than 1.0 mm, indicating a potentially greater safety margin compared to the standard Holmium:YAG laser.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Collateral damage to the ureter and Nitinol stone baskets during thulium fiber laser lithotripsy. Wilson, CR., Hardy, LA., Irby, PB., et al.[2016]

The SuperPulse Thulium fiber laser (SP TFL) is an effective and safe treatment for small calyceal stones in the lower pole of the kidney, achieving a stone-free rate of 86.6% after 90 days in a study of 15 patients.

The use of small laser fibers allows for better maneuverability during flexible ureteroscopy, enabling successful treatment even in challenging anatomical conditions, with a low complication rate of 6.6%.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Flexible ureteroscopy for lower pole renal stones: novel superpulse thulium (TM) fiber laser lithotripsy]. Rapoport, LM., Gazimiev, MA., Korolev, DO., et al.[2021]

In a study of 126 pediatric patients undergoing retrograde intrarenal surgery for kidney stones, both thulium fiber laser (TFL) and high-power Holmium:YAG laser were found to be safe and effective, with similar stone-free rates (81.4% for Holmium:YAG vs. 89.7% for TFL).

The TFL group had a significantly shorter operative time (49.5 minutes) and a lower re-intervention rate (6.89%) compared to the Holmium:YAG group (64.3 minutes and 14.4%, respectively), suggesting TFL may offer advantages in surgical efficiency.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Comparing outcomes of thulium fiber laser versus high-power Holmium:YAG laser lithotripsy in pediatric patients managed with RIRS for kidney stones. A multicenter retrospective study. Candela, L., Solano, C., Castellani, D., et al.[2023]

In a study of 174 patients with ureteral stones, the new super pulse thulium fiber laser (SP TFL) demonstrated a shorter operation time compared to the holmium laser, with an average of 24.7 minutes versus 32.4 minutes.

The SP TFL resulted in a higher stone-free rate at 30 days post-treatment, with no residual stones compared to five cases in the holmium laser group, indicating its superior efficacy in ureterolithotripsy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical Comparison of Super Pulse Thulium Fiber Laser and High-Power Holmium Laser for Ureteral Stone Management. Martov, AG., Ergakov, DV., Guseynov, M., et al.[2021]

Thulium fiber laser (TFL) is a safe and effective treatment for breaking down ureteral and renal stones during retrograde intrarenal surgery (RIRS), with a low overall complication rate observed in a study of 50 patients.

The study utilized specific laser settings for different stone types, showing that TFL can be tailored for optimal performance based on stone size and density, enhancing its efficacy in lithotripsy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Initial clinical experience with the new thulium fiber laser: first 50 cases. Corrales, M., Traxer, O.[2022]

The SuperPulsed Thulium fiber laser offers significant advantages over the traditional Holmium:YAG lasers for laser lithotripsy, including a broader range of pulse energy and frequency, leading to faster stone ablation rates (1.5 to 4 times faster) and the production of finer stone dust.

This new laser technology is thermodynamically safe when used with proper irrigation flow and power settings, making it a promising option for ureteroscopic stone dusting and addressing limitations of previous laser systems.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

SuperPulsed Thulium fiber laser: The ultimate laser for lithotripsy? Keller, EX., Traxer, O.[2020]

The superpulse thulium fiber laser demonstrated superior stone ablation rates compared to the holmium:YAG laser, achieving threefold faster dusting for calcium oxalate stones and 2.5-fold for uric acid stones, indicating its efficacy in lithotripsy.

The thulium fiber laser produced lower retropulsion effects, requiring a higher energy threshold to initiate stone movement, which may enhance safety and precision during procedures compared to the holmium:YAG laser.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Preclinical comparison of superpulse thulium fiber laser and a holmium:YAG laser for lithotripsy. Andreeva, V., Vinarov, A., Yaroslavsky, I., et al.[2021]

References

1. United States pubmed.ncbi.nlm.nih.gov

Enhanced thulium fiber laser lithotripsy using micro-pulse train modulation. [2019]

2. United States pubmed.ncbi.nlm.nih.gov

Collateral damage to the ureter and Nitinol stone baskets during thulium fiber laser lithotripsy. [2016]

3. Russia (Federation) pubmed.ncbi.nlm.nih.gov

[Flexible ureteroscopy for lower pole renal stones: novel superpulse thulium (TM) fiber laser lithotripsy]. [2021]

4. Italy pubmed.ncbi.nlm.nih.gov

Comparing outcomes of thulium fiber laser versus high-power Holmium:YAG laser lithotripsy in pediatric patients managed with RIRS for kidney stones. A multicenter retrospective study. [2023]

5. United States pubmed.ncbi.nlm.nih.gov

Clinical Comparison of Super Pulse Thulium Fiber Laser and High-Power Holmium Laser for Ureteral Stone Management. [2021]

6. Germany pubmed.ncbi.nlm.nih.gov

Initial clinical experience with the new thulium fiber laser: first 50 cases. [2022]

7. Spain pubmed.ncbi.nlm.nih.gov

SuperPulsed Thulium fiber laser: The ultimate laser for lithotripsy? [2020]

8. Germany pubmed.ncbi.nlm.nih.gov

Preclinical comparison of superpulse thulium fiber laser and a holmium:YAG laser for lithotripsy. [2021]