Aminophylline to help ureteric access sheath placement during flexible ureteroscopy

Efficacy of Intra-ureteric Aminophylline Instillation on Flexible Ureteroscopy Procedure: A Randomized Controlled Study

Not applicable Interventional Ain Shams University · NCT06830577

This trial will test whether putting aminophylline into the ureter before flexible ureteroscopy helps place the ureteric access sheath and reduces ureteric injuries for patients with upper ureter or kidney stones smaller than 2 cm.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment129 (estimated)
Ages18 Years and up
SexAll
SponsorAin Shams University Academic / other
Locations1 site (Cairo, Abassia)
Trial IDNCT06830577 on ClinicalTrials.gov

What this trial studies

Urolithiasis of the upper ureter and kidney is commonly treated with flexible ureteroscopy (FURS) using a ureteric access sheath (UAS). Aminophylline, a smooth-muscle relaxant, has been used previously to ease endoscopic procedures and may facilitate UAS placement. In this interventional trial, patients are assigned to one of three groups: intra-ureteric aminophylline instillation, traditional sequential teflon ureteral dilators, or a combination of both, with outcomes recorded during FURS. Primary outcomes include success or failure of UAS placement, operative time, bleeding, intra/postoperative complications, and stone clearance assessed by CT at three weeks at Ain Shams University Hospitals in Cairo.

Who should consider this trial

Good fit: Ideal candidates are patients with upper ureteric or renal stones under 2 cm who do not have active urinary infection, ureteric strictures, prior DJ stenting, significant renal or hepatic impairment, or any contraindication to aminophylline.

Not a fit: Patients with ureteric strictures, anatomic or functional renal disorders, active infection, coagulopathy, prior stenting, or contraindications to aminophylline (including pregnancy, certain cardiac, neurologic, renal or hepatic diseases) are unlikely to benefit from this intervention.

Why it matters

Potential benefit: If successful, this approach could make sheath placement easier, reduce ureteric injuries and complications, and shorten operative time for patients undergoing FURS.

How similar studies have performed: Aminophylline has previously been used intravesically to facilitate rigid ureteroscopy with reduced complications, but intra-ureteric use specifically to aid UAS placement during flexible ureteroscopy is relatively novel with limited prior data.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Upper ureteric stones or renal stones \< 2 cm

Exclusion Criteria:

1. Ureteric strictures.
2. anatomic renal disorders
3. functional renal disorders
4. Urinary tract infection.
5. Coagulopathy and uncorrected bleeding disorders.
6. Prior DJ stenting
7. any contraindication for aminophylline use: (hypersensitivity to theophylline, ethylenediamine, or any component of the drug formulation, pregnancy or lactation, active peptic ulcer, presence of cardiologic diseases, presence of neurologic diseases, presence of renal impairment and presence of hepatic dysfunction)

Where this trial is running

Cairo, Abassia

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Stones, KidneyUreteric InjuryAminophyllineUreteric access sheathureteric injuryFlexible Uretroscopy
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.