An interventional study of Semirigid TFL ureterolithotripsy with Tissue Sensor activated. and Semirigid TFL ureterolithotripsy with Tissue Sensor deactivated. in Nephrolithiasis, sponsored by Botkin Hospital. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-22.
Sponsored by Botkin Hospital · Not applicable, Interventional, and Treatment
Tissue Sensor (TS) is a technology designed to automatically deactivate laser emission when contact between the laser fiber and tissue is detected. It is hypothesized that the use of TS during contact laser ureterolithotripsy may reduce unintended laser exposure of the ureteral mucosa, thereby decreasing the risk of immediate thermal injury to the ureteral wall and subsequent scar-related narrowing.
To reduce the influence of baseline risk factors for stricture, the study will enroll a homogeneous population of patients without urinary tract anomalies, previous surgery on the study ureter, or impacted stones. The procedure will be performed according to a standardized protocol using a semirigid ureteroscope, a thulium fiber laser, and predefined technical restrictions. The study is limited to patients with stones in the mid or distal ureter. This approach is intended to minimize the likelihood of stone retropulsion into the kidney, standardize the surgical technique, reduce the need for conversion to flexible ureteroscopy, and maximize comparability between the study groups.
324 studies on the registry are indexed under Nephrolithiasis; 90 are open to participants now.
This study's planned enrollment of 121 is above the median of 92 across 257 interventional studies indexed under Nephrolithiasis.
Browse Nephrolithiasis studies →Botkin Hospital is the lead sponsor of 8 studies on the registry; 6 are open to participants now.
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Age 18 years or older.
Exclusion Criteria:
Age 18 years or older.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Semirigid TFL ureterolithotripsy will be performed with Tissue Sensor activated. All automatic system trigger events will be recorded by the laser system or in the study case report form and, whenever possible, synchronized with the procedure video recording
Procedure: Semirigid TFL ureterolithotripsy with Tissue Sensor activated.
Semirigid TFL ureterolithotripsy will be performed with Tissue Sensor deactivated. Visually confirmed contacts between the activated laser fiber and the ureteral mucosa will be recorded from the procedure video
Procedure: Semirigid TFL ureterolithotripsy with Tissue Sensor deactivated.
Semirigid TFL ureterolithotripsy will be performed with Tissue Sensor activated. All automatic system trigger events will be recorded by the laser system or in the study case report form and, whenever possible, synchronized with the procedure video recording
Semirigid TFL ureterolithotripsy will be performed with Tissue Sensor deactivated. Visually confirmed contacts between the activated laser fiber and the ureteral mucosa will be recorded from the procedure video.
Incidence of intraoperative laser-induced injury to the ureteral mucosa
Incidence of intraoperative laser-induced injury to the ureteral mucosa, defined as any visible injury compatible with exposure to an activated laser fiber, as determined by independent blinded video assessment.
Time frame: intraoperative
Incidence of postoperative ureteral stricture
Incidence of postoperative ureteral stricture detected during the 12 months after the intervention. * Stone-free rate on low-dose non-contrast CT at 1 month. * Incidence and total number of Tissue Sensor trigger events in the TS group. * Incidence and total number of visually confirmed contacts between an activated laser fiber and the mucosa in the control group. * Number of trigger events or contacts per minute of laser activation. * Severity of mucosal injury according to the standardized scale. * Total operative time. * Lithotripsy time. * Cumulative laser activation time. * Migration of the stone or fragments into the kidney. * Need for conversion to flexible ureteroscopy or repeat intervention. * Type and duration of postoperative drainage. * Postoperative complications according to the Clavien-Dindo classification. * New or progressive hydronephrosis during follow-up.
Time frame: 12 months.
No study locations are listed for this record.
Start is estimated for Oct 2026; primary completion for Oct 2028, 24 months later.
Of 134 non-industry interventional studies with no phase under Nephrolithiasis, half reached primary completion within 25 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 40. This study's planned 24 months is close to that.
Counting every sponsor, half of 140 studies reached it within 24 months; a quarter within 12 and three quarters within 38.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Sep 2026. You cannot join it, but the record below documents what was studied.
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